On 28/02/2022 14:00, Recliner wrote:
> On Mon, 28 Feb 2022 13:54:28 +0000, ColinR <rail@greystane.shetland.co.uk> wrote:
>
>> On 28/02/2022 13:32, Recliner wrote:
>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>
>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>
>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>
>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>
>>>>>>>>>> Nuclear power has to build layer up on layer of protection systems which
>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>
>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>
>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>
>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable state by badly
>>>>>>>> executed experiment
>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have been much,
>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>
>>>>>>> Yes, but that’s the point. Not everything works as expected. It’s easy to
>>>>>>> be wise after the event. Look up Feynman’s comments about the probability
>>>>>>> of Space Shuttle failure as quoted by NASA and what the on-the-ground NASA
>>>>>>> engineers thought the probability of failure was, made when he was on the
>>>>>>> Challenger enquiry. The
>>>>>>
>>>>>> I think my point is that there were specific causes for each of those
>>>>>> accidents, and the others, which were different; that there’s (probably!)
>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>> inevitable failures. It would also be nice to think that engineers have
>>>>>> learned the lessons of each event and will be able to mitigate those flaws
>>>>>> in future, but I’m not in any position to know that.
>>>>>>
>>>>>>> Empirical evidence shows that there’s a serious reactor accident somewhere
>>>>>>> in the world every 10 to 20 years.
>>>>>>
>>>>>> Though of course that’s not an inevitable progression.
>>>>>
>>>>> In general, newer reactors are safer than older ones of the same type, as they incorporate the lessons from earlier
>>>>> failures.
>>>>
>>>> I was simply making the point that there was a greater chance of large
>>>> aircraft crashing into a nuclear power station and causing widespread
>>>> damage than a VLCC making its way through shallow water to take out a a
>>>> couple of wind turbines.
>>>
>>> I suspect that a crash into a nuclear power was far less likely than a large tanker taking out some wind turbines, but
>>> that the consequences of a reactor pressure vessel failure would be far more serious.
>>>
>>> Of course, the risks of both of these possible accidents have been considered for many years. It's one of the many
>>> reasons for the extremely strong containment buildings that enclose modern reactor vessels.
>>>
>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>
>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>
>>>>
>>>> Arguments about modern nuclear power stations having better protection
>>>> than earlier ones applies equally to VLCCs.
>>>
>>> Does it?
>>
>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>> hulled.
>
> Do they not still only have a single engine, screw and rudder?

Generally speaking yes, although some shuttle tankers are better
equipped. However, the risks of a cargo spillage are greatly less now
than they were 20 odd years ago (cannot recall when the rules on
new-builds changed) as any hull damage has to be severe enough to not
only rupture the ship's hull but also rupture the cargo tanks which are
some distance inside the hull plating (1m+ I believe?).

--
Colin

ColinR <rail@greystane.shetland.co.uk> wrote:
> On 28/02/2022 14:00, Recliner wrote:
>> On Mon, 28 Feb 2022 13:54:28 +0000, ColinR <rail@greystane.shetland.co.uk> wrote:
>>
>>> On 28/02/2022 13:32, Recliner wrote:
>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>
>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>
>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>
>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>
>>>>>>>>>>> Nuclear power has to build layer up on layer of protection systems which
>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>
>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>
>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>
>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable state by badly
>>>>>>>>> executed experiment
>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have been much,
>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>
>>>>>>>> Yes, but that’s the point. Not everything works as expected. It’s easy to
>>>>>>>> be wise after the event. Look up Feynman’s comments about the probability
>>>>>>>> of Space Shuttle failure as quoted by NASA and what the on-the-ground NASA
>>>>>>>> engineers thought the probability of failure was, made when he was on the
>>>>>>>> Challenger enquiry. The
>>>>>>>
>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>> accidents, and the others, which were different; that there’s (probably!)
>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>> inevitable failures. It would also be nice to think that engineers have
>>>>>>> learned the lessons of each event and will be able to mitigate those flaws
>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>
>>>>>>>> Empirical evidence shows that there’s a serious reactor accident somewhere
>>>>>>>> in the world every 10 to 20 years.
>>>>>>>
>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>
>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>> type, as they incorporate the lessons from earlier
>>>>>> failures.
>>>>>
>>>>> I was simply making the point that there was a greater chance of large
>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>> couple of wind turbines.
>>>>
>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>> large tanker taking out some wind turbines, but
>>>> that the consequences of a reactor pressure vessel failure would be far more serious.
>>>>
>>>> Of course, the risks of both of these possible accidents have been
>>>> considered for many years. It's one of the many
>>>> reasons for the extremely strong containment buildings that enclose
>>>> modern reactor vessels.
>>>>
>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>
>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>
>>>>>
>>>>> Arguments about modern nuclear power stations having better protection
>>>>> than earlier ones applies equally to VLCCs.
>>>>
>>>> Does it?
>>>
>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>> hulled.
>>
>> Do they not still only have a single engine, screw and rudder?
>
> Generally speaking yes, although some shuttle tankers are better
> equipped. However, the risks of a cargo spillage are greatly less now
> than they were 20 odd years ago (cannot recall when the rules on
> new-builds changed) as any hull damage has to be severe enough to not
> only rupture the ship's hull but also rupture the cargo tanks which are
> some distance inside the hull plating (1m+ I believe?).
>

Yes, agreed.

Hopefully they also have better systems and procedures to avoid collisions
these days, just as planes are less likely to crash these days?

On 28/02/2022 16:43, Recliner wrote:
> ColinR <rail@greystane.shetland.co.uk> wrote:
>> On 28/02/2022 14:00, Recliner wrote:
>>> On Mon, 28 Feb 2022 13:54:28 +0000, ColinR <rail@greystane.shetland.co.uk> wrote:
>>>
>>>> On 28/02/2022 13:32, Recliner wrote:
>>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>
>>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>
>>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>>
>>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>>
>>>>>>>>>>>> Nuclear power has to build layer up on layer of protection systems which
>>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>>
>>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>>
>>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>>
>>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable state by badly
>>>>>>>>>> executed experiment
>>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have been much,
>>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>>
>>>>>>>>> Yes, but that’s the point. Not everything works as expected. It’s easy to
>>>>>>>>> be wise after the event. Look up Feynman’s comments about the probability
>>>>>>>>> of Space Shuttle failure as quoted by NASA and what the on-the-ground NASA
>>>>>>>>> engineers thought the probability of failure was, made when he was on the
>>>>>>>>> Challenger enquiry. The
>>>>>>>>
>>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>>> accidents, and the others, which were different; that there’s (probably!)
>>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>>> inevitable failures. It would also be nice to think that engineers have
>>>>>>>> learned the lessons of each event and will be able to mitigate those flaws
>>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>>
>>>>>>>>> Empirical evidence shows that there’s a serious reactor accident somewhere
>>>>>>>>> in the world every 10 to 20 years.
>>>>>>>>
>>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>>
>>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>>> type, as they incorporate the lessons from earlier
>>>>>>> failures.
>>>>>>
>>>>>> I was simply making the point that there was a greater chance of large
>>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>>> couple of wind turbines.
>>>>>
>>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>>> large tanker taking out some wind turbines, but
>>>>> that the consequences of a reactor pressure vessel failure would be far more serious.
>>>>>
>>>>> Of course, the risks of both of these possible accidents have been
>>>>> considered for many years. It's one of the many
>>>>> reasons for the extremely strong containment buildings that enclose
>>>>> modern reactor vessels.
>>>>>
>>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>>
>>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>>
>>>>>>
>>>>>> Arguments about modern nuclear power stations having better protection
>>>>>> than earlier ones applies equally to VLCCs.
>>>>>
>>>>> Does it?
>>>>
>>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>>> hulled.
>>>
>>> Do they not still only have a single engine, screw and rudder?
>>
>> Generally speaking yes, although some shuttle tankers are better
>> equipped. However, the risks of a cargo spillage are greatly less now
>> than they were 20 odd years ago (cannot recall when the rules on
>> new-builds changed) as any hull damage has to be severe enough to not
>> only rupture the ship's hull but also rupture the cargo tanks which are
>> some distance inside the hull plating (1m+ I believe?).
>>
>
> Yes, agreed.
>
> Hopefully they also have better systems and procedures to avoid collisions
> these days, just as planes are less likely to crash these days?
>

Boeing and the FAA seems to have bypassed the better systems and procedures.

On 28/02/2022 16:43, Recliner wrote:
> ColinR <rail@greystane.shetland.co.uk> wrote:
>> On 28/02/2022 14:00, Recliner wrote:
>>> On Mon, 28 Feb 2022 13:54:28 +0000, ColinR <rail@greystane.shetland.co.uk> wrote:
>>>
>>>> On 28/02/2022 13:32, Recliner wrote:
>>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>
>>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>
>>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>>
>>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>>
>>>>>>>>>>>> Nuclear power has to build layer up on layer of protection systems which
>>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>>
>>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>>
>>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>>
>>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable state by badly
>>>>>>>>>> executed experiment
>>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have been much,
>>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>>
>>>>>>>>> Yes, but that’s the point. Not everything works as expected. It’s easy to
>>>>>>>>> be wise after the event. Look up Feynman’s comments about the probability
>>>>>>>>> of Space Shuttle failure as quoted by NASA and what the on-the-ground NASA
>>>>>>>>> engineers thought the probability of failure was, made when he was on the
>>>>>>>>> Challenger enquiry. The
>>>>>>>>
>>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>>> accidents, and the others, which were different; that there’s (probably!)
>>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>>> inevitable failures. It would also be nice to think that engineers have
>>>>>>>> learned the lessons of each event and will be able to mitigate those flaws
>>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>>
>>>>>>>>> Empirical evidence shows that there’s a serious reactor accident somewhere
>>>>>>>>> in the world every 10 to 20 years.
>>>>>>>>
>>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>>
>>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>>> type, as they incorporate the lessons from earlier
>>>>>>> failures.
>>>>>>
>>>>>> I was simply making the point that there was a greater chance of large
>>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>>> couple of wind turbines.
>>>>>
>>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>>> large tanker taking out some wind turbines, but
>>>>> that the consequences of a reactor pressure vessel failure would be far more serious.
>>>>>
>>>>> Of course, the risks of both of these possible accidents have been
>>>>> considered for many years. It's one of the many
>>>>> reasons for the extremely strong containment buildings that enclose
>>>>> modern reactor vessels.
>>>>>
>>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>>
>>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>>
>>>>>>
>>>>>> Arguments about modern nuclear power stations having better protection
>>>>>> than earlier ones applies equally to VLCCs.
>>>>>
>>>>> Does it?
>>>>
>>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>>> hulled.
>>>
>>> Do they not still only have a single engine, screw and rudder?
>>
>> Generally speaking yes, although some shuttle tankers are better
>> equipped. However, the risks of a cargo spillage are greatly less now
>> than they were 20 odd years ago (cannot recall when the rules on
>> new-builds changed) as any hull damage has to be severe enough to not
>> only rupture the ship's hull but also rupture the cargo tanks which are
>> some distance inside the hull plating (1m+ I believe?).
>>
>
> Yes, agreed.
>
> Hopefully they also have better systems and procedures to avoid collisions
> these days, just as planes are less likely to crash these days?
>

Yep, back in the day when I was on VLCCs position fixing was by
observing lights (lighthouses, buoys etc) and using radar ranges and
bearings from coastal features. Once leaving the coast we were down to
astronomical position fixing (sun sights / star sights) which were
limited in timing - star sights at dawn and dusk, sun sights run up to a
noon (astronomical noon) fix. These were dependant upon the accuracy of
the sextants and the skill of the navigators. A position would have been
anything up to 5 miles out if the horizon was a bit wafty - and then
only if it was not overcast. If overcast then dead reckoning was the
norm. GPS has changed all that (via transit satellite, Decca, Loran etc).

And collisions are fewer as radar has improved. Radar is not infallable
- there were a number of "radar assisted collisions" in the period after
the war until there was more training / better radars. It was not until
the 1970s that radars were readily used - when I first went to sea the
mantra of "do not turn on the radar unless we need it" was the norm, and
not unreasonable as the early sets were somewhat unreliable, to put it
mildly!

--
Colin

ColinR <rail@greystane.shetland.co.uk> wrote:
> On 28/02/2022 16:43, Recliner wrote:
>> ColinR <rail@greystane.shetland.co.uk> wrote:
>>> On 28/02/2022 14:00, Recliner wrote:
>>>> On Mon, 28 Feb 2022 13:54:28 +0000, ColinR <rail@greystane.shetland.co.uk> wrote:
>>>>
>>>>> On 28/02/2022 13:32, Recliner wrote:
>>>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>
>>>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>
>>>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>>>
>>>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Nuclear power has to build layer up on layer of protection systems which
>>>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>>>
>>>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>>>
>>>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>>>
>>>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable state by badly
>>>>>>>>>>> executed experiment
>>>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have been much,
>>>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>>>
>>>>>>>>>> Yes, but that’s the point. Not everything works as expected. It’s easy to
>>>>>>>>>> be wise after the event. Look up Feynman’s comments about the probability
>>>>>>>>>> of Space Shuttle failure as quoted by NASA and what the on-the-ground NASA
>>>>>>>>>> engineers thought the probability of failure was, made when he was on the
>>>>>>>>>> Challenger enquiry. The
>>>>>>>>>
>>>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>>>> accidents, and the others, which were different; that there’s (probably!)
>>>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>>>> inevitable failures. It would also be nice to think that engineers have
>>>>>>>>> learned the lessons of each event and will be able to mitigate those flaws
>>>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>>>
>>>>>>>>>> Empirical evidence shows that there’s a serious reactor accident somewhere
>>>>>>>>>> in the world every 10 to 20 years.
>>>>>>>>>
>>>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>>>
>>>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>>>> type, as they incorporate the lessons from earlier
>>>>>>>> failures.
>>>>>>>
>>>>>>> I was simply making the point that there was a greater chance of large
>>>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>>>> couple of wind turbines.
>>>>>>
>>>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>>>> large tanker taking out some wind turbines, but
>>>>>> that the consequences of a reactor pressure vessel failure would be far more serious.
>>>>>>
>>>>>> Of course, the risks of both of these possible accidents have been
>>>>>> considered for many years. It's one of the many
>>>>>> reasons for the extremely strong containment buildings that enclose
>>>>>> modern reactor vessels.
>>>>>>
>>>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>>>
>>>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>>>
>>>>>>>
>>>>>>> Arguments about modern nuclear power stations having better protection
>>>>>>> than earlier ones applies equally to VLCCs.
>>>>>>
>>>>>> Does it?
>>>>>
>>>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>>>> hulled.
>>>>
>>>> Do they not still only have a single engine, screw and rudder?
>>>
>>> Generally speaking yes, although some shuttle tankers are better
>>> equipped. However, the risks of a cargo spillage are greatly less now
>>> than they were 20 odd years ago (cannot recall when the rules on
>>> new-builds changed) as any hull damage has to be severe enough to not
>>> only rupture the ship's hull but also rupture the cargo tanks which are
>>> some distance inside the hull plating (1m+ I believe?).
>>>
>>
>> Yes, agreed.
>>
>> Hopefully they also have better systems and procedures to avoid collisions
>> these days, just as planes are less likely to crash these days?
>>
>
> Yep, back in the day when I was on VLCCs position fixing was by
> observing lights (lighthouses, buoys etc) and using radar ranges and
> bearings from coastal features. Once leaving the coast we were down to
> astronomical position fixing (sun sights / star sights) which were
> limited in timing - star sights at dawn and dusk, sun sights run up to a
> noon (astronomical noon) fix. These were dependant upon the accuracy of
> the sextants and the skill of the navigators. A position would have been
> anything up to 5 miles out if the horizon was a bit wafty - and then
> only if it was not overcast. If overcast then dead reckoning was the
> norm. GPS has changed all that (via transit satellite, Decca, Loran etc).
>
> And collisions are fewer as radar has improved. Radar is not infallable
> - there were a number of "radar assisted collisions" in the period after
> the war until there was more training / better radars. It was not until
> the 1970s that radars were readily used - when I first went to sea the
> mantra of "do not turn on the radar unless we need it" was the norm, and
> not unreasonable as the early sets were somewhat unreliable, to put it
> mildly!
>

And, as the AIS-assisted radar screen I showed recently illustrated, the
system is constantly scanning for potential collisions and generates an
alarm if the computer identifies such a risk within, say, 20 minutes.
That's much better than relying on an alert lookout.

On 28/02/2022 13:32, Recliner wrote:
> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall <rail@greywall.demon.co.uk> wrote:
>
>> On 28/02/2022 12:42, Recliner wrote:
>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>
>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>
>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>
>>>>>>>> Nuclear power has to build layer up on layer of protection systems which
>>>>>>>> other generations system are not required to have.
>>>>>>>
>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>
>>>>>> <cough> Three Mile Island </cough>
>>>>>>
>>>>>> Chernobyl - fundamentally flawed design driven into unstable state by badly
>>>>>> executed experiment
>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>> Three Mile Island - technical design faults and operator error
>>>>>> Windscale extremely dodgy design (in hindsight) which would have been much,
>>>>>> much worse except for Cockroft’s Folly
>>>>>
>>>>> Yes, but that’s the point. Not everything works as expected. It’s easy to
>>>>> be wise after the event. Look up Feynman’s comments about the probability
>>>>> of Space Shuttle failure as quoted by NASA and what the on-the-ground NASA
>>>>> engineers thought the probability of failure was, made when he was on the
>>>>> Challenger enquiry. The
>>>>
>>>> I think my point is that there were specific causes for each of those
>>>> accidents, and the others, which were different; that there’s (probably!)
>>>> not a particular systematic flaw in nuclear engineering which causes
>>>> inevitable failures. It would also be nice to think that engineers have
>>>> learned the lessons of each event and will be able to mitigate those flaws
>>>> in future, but I’m not in any position to know that.
>>>>
>>>>> Empirical evidence shows that there’s a serious reactor accident somewhere
>>>>> in the world every 10 to 20 years.
>>>>
>>>> Though of course that’s not an inevitable progression.
>>>
>>> In general, newer reactors are safer than older ones of the same type, as they incorporate the lessons from earlier
>>> failures.
>>
>> I was simply making the point that there was a greater chance of large
>> aircraft crashing into a nuclear power station and causing widespread
>> damage than a VLCC making its way through shallow water to take out a a
>> couple of wind turbines.
>
> I suspect that a crash into a nuclear power was far less likely than a large tanker taking out some wind turbines, but
> that the consequences of a reactor pressure vessel failure would be far more serious.
>
> Of course, the risks of both of these possible accidents have been considered for many years. It's one of the many
> reasons for the extremely strong containment buildings that enclose modern reactor vessels.
>
> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>
> https://hakaimagazine.com/news/designing-against-disaster/
>
>>
>> Arguments about modern nuclear power stations having better protection
>> than earlier ones applies equally to VLCCs.
>
> Does it?

Double hulls being the most obvious.

--
Graeme Wall
This account not read.

On 28/02/2022 13:54, ColinR wrote:
> On 28/02/2022 13:32, Recliner wrote:
>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall
>> <rail@greywall.demon.co.uk> wrote:
>>
>>> On 28/02/2022 12:42, Recliner wrote:
>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>
>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>
>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>
>>>>>>>>> Nuclear power has to build layer up on layer of protection
>>>>>>>>> systems which
>>>>>>>>> other generations system are not required to have.
>>>>>>>>
>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>
>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>
>>>>>>> Chernobyl - fundamentally flawed design driven into unstable
>>>>>>> state by badly
>>>>>>> executed experiment
>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>> Windscale extremely dodgy design (in hindsight) which would have
>>>>>>> been much,
>>>>>>> much worse except for Cockroft’s Folly
>>>>>>
>>>>>> Yes, but that’s the point.  Not everything works as expected.
>>>>>> It’s easy to
>>>>>> be wise after the event.  Look up Feynman’s comments about the
>>>>>> probability
>>>>>> of Space Shuttle failure as quoted by NASA and what the
>>>>>> on-the-ground NASA
>>>>>> engineers thought the probability of failure was, made when he was
>>>>>> on the
>>>>>> Challenger enquiry. The
>>>>>
>>>>> I think my point is that there were specific causes for each of those
>>>>> accidents, and the others, which were different; that there’s
>>>>> (probably!)
>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>> inevitable failures.  It would also be nice to think that engineers
>>>>> have
>>>>> learned the lessons of each event and will be able to mitigate
>>>>> those flaws
>>>>> in future, but I’m not in any position to know that.
>>>>>
>>>>>> Empirical evidence shows that there’s a serious reactor accident
>>>>>> somewhere
>>>>>> in the world every 10 to 20 years.
>>>>>
>>>>> Though of course that’s not an inevitable progression.
>>>>
>>>> In general, newer reactors are safer than older ones of the same
>>>> type, as they incorporate the lessons from earlier
>>>> failures.
>>>
>>> I was simply making the point that there was a greater chance of large
>>> aircraft crashing into a nuclear power station and causing widespread
>>> damage than a VLCC making its way through shallow water to take out a a
>>> couple of wind turbines.
>>
>> I suspect that a crash into a nuclear power was far less likely than a
>> large tanker taking out some wind turbines, but
>> that the consequences of a reactor pressure vessel failure would be
>> far more serious.
>>
>> Of course, the risks of both of these possible accidents have been
>> considered for many years. It's one of the many
>> reasons for the extremely strong containment buildings that enclose
>> modern reactor vessels.
>>
>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>
>> https://hakaimagazine.com/news/designing-against-disaster/
>>
>>>
>>> Arguments about modern nuclear power stations having better protection
>>> than earlier ones applies equally to VLCCs.
>>
>> Does it?
>
> Yes - when I sailed on VLCCs they were single hulled, now all are double
> hulled.
>

You will know then, what is the chance of a laden VLCC being able to
enter waters shallow enough to support a wind farm?

--
Graeme Wall
This account not read.

Graeme Wall <rail@greywall.demon.co.uk> wrote:
> On 28/02/2022 13:54, ColinR wrote:
>> On 28/02/2022 13:32, Recliner wrote:
>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall
>>> <rail@greywall.demon.co.uk> wrote:
>>>
>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>
>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>
>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>
>>>>>>>>>> Nuclear power has to build layer up on layer of protection
>>>>>>>>>> systems which
>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>
>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>
>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>
>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable
>>>>>>>> state by badly
>>>>>>>> executed experiment
>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have
>>>>>>>> been much,
>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>
>>>>>>> Yes, but that’s the point.  Not everything works as expected.
>>>>>>> It’s easy to
>>>>>>> be wise after the event.  Look up Feynman’s comments about the
>>>>>>> probability
>>>>>>> of Space Shuttle failure as quoted by NASA and what the
>>>>>>> on-the-ground NASA
>>>>>>> engineers thought the probability of failure was, made when he was
>>>>>>> on the
>>>>>>> Challenger enquiry. The
>>>>>>
>>>>>> I think my point is that there were specific causes for each of those
>>>>>> accidents, and the others, which were different; that there’s
>>>>>> (probably!)
>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>> inevitable failures.  It would also be nice to think that engineers
>>>>>> have
>>>>>> learned the lessons of each event and will be able to mitigate
>>>>>> those flaws
>>>>>> in future, but I’m not in any position to know that.
>>>>>>
>>>>>>> Empirical evidence shows that there’s a serious reactor accident
>>>>>>> somewhere
>>>>>>> in the world every 10 to 20 years.
>>>>>>
>>>>>> Though of course that’s not an inevitable progression.
>>>>>
>>>>> In general, newer reactors are safer than older ones of the same
>>>>> type, as they incorporate the lessons from earlier
>>>>> failures.
>>>>
>>>> I was simply making the point that there was a greater chance of large
>>>> aircraft crashing into a nuclear power station and causing widespread
>>>> damage than a VLCC making its way through shallow water to take out a a
>>>> couple of wind turbines.
>>>
>>> I suspect that a crash into a nuclear power was far less likely than a
>>> large tanker taking out some wind turbines, but
>>> that the consequences of a reactor pressure vessel failure would be
>>> far more serious.
>>>
>>> Of course, the risks of both of these possible accidents have been
>>> considered for many years. It's one of the many
>>> reasons for the extremely strong containment buildings that enclose
>>> modern reactor vessels.
>>>
>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>
>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>
>>>>
>>>> Arguments about modern nuclear power stations having better protection
>>>> than earlier ones applies equally to VLCCs.
>>>
>>> Does it?
>>
>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>> hulled.
>>
>
> You will know then, what is the chance of a laden VLCC being able to
> enter waters shallow enough to support a wind farm?
>

I believe fixed foundation offshore wind turbines can be installed in water
depths of up to 50m, though of course most wind farms will be in shallower
water. The largest ULCCs have a draft of about 28m.

So, yes, a fully laden ULCC could theoretically stray into an offshore wind
farm. Of course, the crew would have to be ignoring their charts and the
radar to do so, so it would probably only happen if the ship was drifting
or otherwise out of control.

Recliner <recliner.usenet@gmail.com> wrote:
> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>> On 28/02/2022 13:54, ColinR wrote:
>>> On 28/02/2022 13:32, Recliner wrote:
>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall
>>>> <rail@greywall.demon.co.uk> wrote:
>>>>
>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>
>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>
>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>
>>>>>>>>>>> Nuclear power has to build layer up on layer of protection
>>>>>>>>>>> systems which
>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>
>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>
>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>
>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable
>>>>>>>>> state by badly
>>>>>>>>> executed experiment
>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have
>>>>>>>>> been much,
>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>
>>>>>>>> Yes, but that’s the point.  Not everything works as expected.
>>>>>>>> It’s easy to
>>>>>>>> be wise after the event.  Look up Feynman’s comments about the
>>>>>>>> probability
>>>>>>>> of Space Shuttle failure as quoted by NASA and what the
>>>>>>>> on-the-ground NASA
>>>>>>>> engineers thought the probability of failure was, made when he was
>>>>>>>> on the
>>>>>>>> Challenger enquiry. The
>>>>>>>
>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>> accidents, and the others, which were different; that there’s
>>>>>>> (probably!)
>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>> inevitable failures.  It would also be nice to think that engineers
>>>>>>> have
>>>>>>> learned the lessons of each event and will be able to mitigate
>>>>>>> those flaws
>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>
>>>>>>>> Empirical evidence shows that there’s a serious reactor accident
>>>>>>>> somewhere
>>>>>>>> in the world every 10 to 20 years.
>>>>>>>
>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>
>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>> type, as they incorporate the lessons from earlier
>>>>>> failures.
>>>>>
>>>>> I was simply making the point that there was a greater chance of large
>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>> couple of wind turbines.
>>>>
>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>> large tanker taking out some wind turbines, but
>>>> that the consequences of a reactor pressure vessel failure would be
>>>> far more serious.
>>>>
>>>> Of course, the risks of both of these possible accidents have been
>>>> considered for many years. It's one of the many
>>>> reasons for the extremely strong containment buildings that enclose
>>>> modern reactor vessels.
>>>>
>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>
>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>
>>>>>
>>>>> Arguments about modern nuclear power stations having better protection
>>>>> than earlier ones applies equally to VLCCs.
>>>>
>>>> Does it?
>>>
>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>> hulled.
>>>
>>
>> You will know then, what is the chance of a laden VLCC being able to
>> enter waters shallow enough to support a wind farm?
>>
>
> I believe fixed foundation offshore wind turbines can be installed in water
> depths of up to 50m, though of course most wind farms will be in shallower
> water. The largest ULCCs have a draft of about 28m.
>
> So, yes, a fully laden ULCC could theoretically stray into an offshore wind
> farm. Of course, the crew would have to be ignoring their charts and the
> radar to do so, so it would probably only happen if the ship was drifting
> or otherwise out of control.
>
>

Every time there’s a rescue of a big ship on a TV reality programme the
fundamental issue seems to be loss of power and then drifting (usually in a
storm). I’m uncertain if this is the major cause of maritime accidents, but
it seems to be on TV.

Incidentally, I wonder if anyone knows in what circumstances military
aircraft turn their transponders on and off when flying in civilan
airspace?

I've been tracking USAF and RAF air tankers doing circuits over Romania,
obviously to refuel military aircraft in the area (currently, the on-duty
aircraft is a German-based USAF KC-135-R, doing circuits over Covasna, judt
to the east of Brașov; last night it was an RAF Voyager, and before that, a
USAF KC-10 from Mildenhall).

Other than a NATO AWACS E3, and a couple of RAF Typhoons also doing
circuits over Romania with their transponders briefly turned on, there's no
sign of which military aircraft are being refuelled. I assume there must be
some other NATO fighters patrolling the border with their transponders off,
but also wondered if it was technically possible for Ukrainian MiG-29s and
Su-27s to be refuelled by NATO tankers?

Not only are there no civilian aircraft flying over Ukraine, but there
seems to be a large air exclusion zone over western Russia, from Smolensk
to Volgograd.

Recliner <recliner.usenet@gmail.com> wrote:
> Incidentally, I wonder if anyone knows in what circumstances military
> aircraft turn their transponders on and off when flying in civilan
> airspace?
>
> I've been tracking USAF and RAF air tankers doing circuits over Romania,
> obviously to refuel military aircraft in the area (currently, the on-duty
> aircraft is a German-based USAF KC-135-R, doing circuits over Covasna, judt
> to the east of Brașov; last night it was an RAF Voyager, and before that, a
> USAF KC-10 from Mildenhall).
>
> Other than a NATO AWACS E3, and a couple of RAF Typhoons also doing
> circuits over Romania with their transponders briefly turned on, there's no
> sign of which military aircraft are being refuelled. I assume there must be
> some other NATO fighters patrolling the border with their transponders off,
> but also wondered if it was technically possible for Ukrainian MiG-29s and
> Su-27s to be refuelled by NATO tankers?
>
> Not only are there no civilian aircraft flying over Ukraine, but there
> seems to be a large air exclusion zone over western Russia, from Smolensk
> to Volgograd.

Presumably some of the military flights are protected by NOTAMs restricting
civilian flights. There’s also the fact that (some) military flying
happens well above the likely civilian flight ceilings - the drones that
have been patrolling Ukraine and the Black Sea coasts recently seem to
cruise at 55,000 ft.

When the Mildenhall KC-135s do racetracks over the North Sea there are
rarely any other aircraft visible in attendance.

Sam

--
The entity formerly known as Sam.Wilson@ed.ac.uk
Spit the dummy to reply

On Tue, 1 Mar 2022 11:38:03 -0000 (UTC), Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:

>Recliner <recliner.usenet@gmail.com> wrote:
>> Incidentally, I wonder if anyone knows in what circumstances military
>> aircraft turn their transponders on and off when flying in civilan
>> airspace?
>>
>> I've been tracking USAF and RAF air tankers doing circuits over Romania,
>> obviously to refuel military aircraft in the area (currently, the on-duty
>> aircraft is a German-based USAF KC-135-R, doing circuits over Covasna, judt
>> to the east of Bra?ov; last night it was an RAF Voyager, and before that, a
>> USAF KC-10 from Mildenhall).
>>
>> Other than a NATO AWACS E3, and a couple of RAF Typhoons also doing
>> circuits over Romania with their transponders briefly turned on, there's no
>> sign of which military aircraft are being refuelled. I assume there must be
>> some other NATO fighters patrolling the border with their transponders off,
>> but also wondered if it was technically possible for Ukrainian MiG-29s and
>> Su-27s to be refuelled by NATO tankers?
>>
>> Not only are there no civilian aircraft flying over Ukraine, but there
>> seems to be a large air exclusion zone over western Russia, from Smolensk
>> to Volgograd.
>
>Presumably some of the military flights are protected by NOTAMs restricting
>civilian flights. There’s also the fact that (some) military flying
>happens well above the likely civilian flight ceilings - the drones that
>have been patrolling Ukraine and the Black Sea coasts recently seem to
>cruise at 55,000 ft.
>
>When the Mildenhall KC-135s do racetracks over the North Sea there are
>rarely any other aircraft visible in attendance.

I've seen civilian planes being tracked surprisingly close to the racetracks over Romania, but at a higher altitude.

In message <svl0ir$fl9$1@dont-email.me>, at 11:38:03 on Tue, 1 Mar 2022,
Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> remarked:

>When the Mildenhall KC-135s do racetracks over the North Sea there are
>rarely any other aircraft visible in attendance.

Do you mean "in attendance and being refuelled"?

FWIW those tankers frequently fly literally over my house (+/- 50m) and
the base commander keeps his hand in flying one from time to time. Why
do I know that - I had lunch with him a few years ago. Hopefully I won't
now get a visit from any black helicopters (they prefer to use Ospreys)

https://www.youtube.com/watch?v=F9snZJadgkQ
--
Roland Perry

On 01/03/2022 10:15, Recliner wrote:
> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>> On 28/02/2022 13:54, ColinR wrote:
>>> On 28/02/2022 13:32, Recliner wrote:
>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall
>>>> <rail@greywall.demon.co.uk> wrote:
>>>>
>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>
>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>
>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>
>>>>>>>>>>> Nuclear power has to build layer up on layer of protection
>>>>>>>>>>> systems which
>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>
>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>
>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>
>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable
>>>>>>>>> state by badly
>>>>>>>>> executed experiment
>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have
>>>>>>>>> been much,
>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>
>>>>>>>> Yes, but that’s the point.  Not everything works as expected.
>>>>>>>> It’s easy to
>>>>>>>> be wise after the event.  Look up Feynman’s comments about the
>>>>>>>> probability
>>>>>>>> of Space Shuttle failure as quoted by NASA and what the
>>>>>>>> on-the-ground NASA
>>>>>>>> engineers thought the probability of failure was, made when he was
>>>>>>>> on the
>>>>>>>> Challenger enquiry. The
>>>>>>>
>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>> accidents, and the others, which were different; that there’s
>>>>>>> (probably!)
>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>> inevitable failures.  It would also be nice to think that engineers
>>>>>>> have
>>>>>>> learned the lessons of each event and will be able to mitigate
>>>>>>> those flaws
>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>
>>>>>>>> Empirical evidence shows that there’s a serious reactor accident
>>>>>>>> somewhere
>>>>>>>> in the world every 10 to 20 years.
>>>>>>>
>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>
>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>> type, as they incorporate the lessons from earlier
>>>>>> failures.
>>>>>
>>>>> I was simply making the point that there was a greater chance of large
>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>> couple of wind turbines.
>>>>
>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>> large tanker taking out some wind turbines, but
>>>> that the consequences of a reactor pressure vessel failure would be
>>>> far more serious.
>>>>
>>>> Of course, the risks of both of these possible accidents have been
>>>> considered for many years. It's one of the many
>>>> reasons for the extremely strong containment buildings that enclose
>>>> modern reactor vessels.
>>>>
>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>
>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>
>>>>>
>>>>> Arguments about modern nuclear power stations having better protection
>>>>> than earlier ones applies equally to VLCCs.
>>>>
>>>> Does it?
>>>
>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>> hulled.
>>>
>>
>> You will know then, what is the chance of a laden VLCC being able to
>> enter waters shallow enough to support a wind farm?
>>
>
> I believe fixed foundation offshore wind turbines can be installed in water
> depths of up to 50m, though of course most wind farms will be in shallower
> water. The largest ULCCs have a draft of about 28m.
>
> So, yes, a fully laden ULCC could theoretically stray into an offshore wind
> farm. Of course, the crew would have to be ignoring their charts and the
> radar to do so, so it would probably only happen if the ship was drifting
> or otherwise out of control.
>

Whilst true, there are well advanced plans (maybe even actual) for
floating wind turbines - these would, I assume, be able to be moored in
deeper water. But they would present a fairly robust radar echo quite
apart from being charted.

--
Colin

ColinR <rail@greystane.shetland.co.uk> wrote:
> On 01/03/2022 10:15, Recliner wrote:
>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>> On 28/02/2022 13:54, ColinR wrote:
>>>> On 28/02/2022 13:32, Recliner wrote:
>>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall
>>>>> <rail@greywall.demon.co.uk> wrote:
>>>>>
>>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>
>>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>>
>>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>>
>>>>>>>>>>>> Nuclear power has to build layer up on layer of protection
>>>>>>>>>>>> systems which
>>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>>
>>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>>
>>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>>
>>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable
>>>>>>>>>> state by badly
>>>>>>>>>> executed experiment
>>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have
>>>>>>>>>> been much,
>>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>>
>>>>>>>>> Yes, but that’s the point.  Not everything works as expected.
>>>>>>>>> It’s easy to
>>>>>>>>> be wise after the event.  Look up Feynman’s comments about the
>>>>>>>>> probability
>>>>>>>>> of Space Shuttle failure as quoted by NASA and what the
>>>>>>>>> on-the-ground NASA
>>>>>>>>> engineers thought the probability of failure was, made when he was
>>>>>>>>> on the
>>>>>>>>> Challenger enquiry. The
>>>>>>>>
>>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>>> accidents, and the others, which were different; that there’s
>>>>>>>> (probably!)
>>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>>> inevitable failures.  It would also be nice to think that engineers
>>>>>>>> have
>>>>>>>> learned the lessons of each event and will be able to mitigate
>>>>>>>> those flaws
>>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>>
>>>>>>>>> Empirical evidence shows that there’s a serious reactor accident
>>>>>>>>> somewhere
>>>>>>>>> in the world every 10 to 20 years.
>>>>>>>>
>>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>>
>>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>>> type, as they incorporate the lessons from earlier
>>>>>>> failures.
>>>>>>
>>>>>> I was simply making the point that there was a greater chance of large
>>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>>> couple of wind turbines.
>>>>>
>>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>>> large tanker taking out some wind turbines, but
>>>>> that the consequences of a reactor pressure vessel failure would be
>>>>> far more serious.
>>>>>
>>>>> Of course, the risks of both of these possible accidents have been
>>>>> considered for many years. It's one of the many
>>>>> reasons for the extremely strong containment buildings that enclose
>>>>> modern reactor vessels.
>>>>>
>>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>>
>>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>>
>>>>>>
>>>>>> Arguments about modern nuclear power stations having better protection
>>>>>> than earlier ones applies equally to VLCCs.
>>>>>
>>>>> Does it?
>>>>
>>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>>> hulled.
>>>>
>>>
>>> You will know then, what is the chance of a laden VLCC being able to
>>> enter waters shallow enough to support a wind farm?
>>>
>>
>> I believe fixed foundation offshore wind turbines can be installed in water
>> depths of up to 50m, though of course most wind farms will be in shallower
>> water. The largest ULCCs have a draft of about 28m.
>>
>> So, yes, a fully laden ULCC could theoretically stray into an offshore wind
>> farm. Of course, the crew would have to be ignoring their charts and the
>> radar to do so, so it would probably only happen if the ship was drifting
>> or otherwise out of control.
>>
>
> Whilst true, there are well advanced plans (maybe even actual) for
> floating wind turbines - these would, I assume, be able to be moored in
> deeper water. But they would present a fairly robust radar echo quite
> apart from being charted.
>

I don't think any floating wind farms are yet in operation, but they're
certainly on the way. Not only could they be moored in much deeper water,
but they may well be much further offshore, where the winds are stronger
and more reliable. So they'll be a greater hazard for shipping.

<https://www.ge.com/news/reports/deep-water-wind-these-huge-floating-wind-turbines-could-help-america-meet-its-renewable>

On 01/03/2022 16:54, Recliner wrote:
> ColinR <rail@greystane.shetland.co.uk> wrote:
>> On 01/03/2022 10:15, Recliner wrote:
>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>> On 28/02/2022 13:54, ColinR wrote:
>>>>> On 28/02/2022 13:32, Recliner wrote:
>>>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall
>>>>>> <rail@greywall.demon.co.uk> wrote:
>>>>>>
>>>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>
>>>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>>>
>>>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Nuclear power has to build layer up on layer of protection
>>>>>>>>>>>>> systems which
>>>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>>>
>>>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>>>
>>>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>>>
>>>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable
>>>>>>>>>>> state by badly
>>>>>>>>>>> executed experiment
>>>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have
>>>>>>>>>>> been much,
>>>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>>>
>>>>>>>>>> Yes, but that’s the point.  Not everything works as expected.
>>>>>>>>>> It’s easy to
>>>>>>>>>> be wise after the event.  Look up Feynman’s comments about the
>>>>>>>>>> probability
>>>>>>>>>> of Space Shuttle failure as quoted by NASA and what the
>>>>>>>>>> on-the-ground NASA
>>>>>>>>>> engineers thought the probability of failure was, made when he was
>>>>>>>>>> on the
>>>>>>>>>> Challenger enquiry. The
>>>>>>>>>
>>>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>>>> accidents, and the others, which were different; that there’s
>>>>>>>>> (probably!)
>>>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>>>> inevitable failures.  It would also be nice to think that engineers
>>>>>>>>> have
>>>>>>>>> learned the lessons of each event and will be able to mitigate
>>>>>>>>> those flaws
>>>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>>>
>>>>>>>>>> Empirical evidence shows that there’s a serious reactor accident
>>>>>>>>>> somewhere
>>>>>>>>>> in the world every 10 to 20 years.
>>>>>>>>>
>>>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>>>
>>>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>>>> type, as they incorporate the lessons from earlier
>>>>>>>> failures.
>>>>>>>
>>>>>>> I was simply making the point that there was a greater chance of large
>>>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>>>> couple of wind turbines.
>>>>>>
>>>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>>>> large tanker taking out some wind turbines, but
>>>>>> that the consequences of a reactor pressure vessel failure would be
>>>>>> far more serious.
>>>>>>
>>>>>> Of course, the risks of both of these possible accidents have been
>>>>>> considered for many years. It's one of the many
>>>>>> reasons for the extremely strong containment buildings that enclose
>>>>>> modern reactor vessels.
>>>>>>
>>>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>>>
>>>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>>>
>>>>>>>
>>>>>>> Arguments about modern nuclear power stations having better protection
>>>>>>> than earlier ones applies equally to VLCCs.
>>>>>>
>>>>>> Does it?
>>>>>
>>>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>>>> hulled.
>>>>>
>>>>
>>>> You will know then, what is the chance of a laden VLCC being able to
>>>> enter waters shallow enough to support a wind farm?
>>>>
>>>
>>> I believe fixed foundation offshore wind turbines can be installed in water
>>> depths of up to 50m, though of course most wind farms will be in shallower
>>> water. The largest ULCCs have a draft of about 28m.
>>>
>>> So, yes, a fully laden ULCC could theoretically stray into an offshore wind
>>> farm. Of course, the crew would have to be ignoring their charts and the
>>> radar to do so, so it would probably only happen if the ship was drifting
>>> or otherwise out of control.
>>>
>>
>> Whilst true, there are well advanced plans (maybe even actual) for
>> floating wind turbines - these would, I assume, be able to be moored in
>> deeper water. But they would present a fairly robust radar echo quite
>> apart from being charted.
>>
>
> I don't think any floating wind farms are yet in operation, but they're
> certainly on the way. Not only could they be moored in much deeper water,
> but they may well be much further offshore, where the winds are stronger
> and more reliable. So they'll be a greater hazard for shipping.
>
> <https://www.ge.com/news/reports/deep-water-wind-these-huge-floating-wind-turbines-could-help-america-meet-its-renewable>
>
>

As that article points out, floating gas and oil platforms have been
around a long time and are, by definition, going to be in seas traversed
by oil/gas tankers. The only vessels that need to go near wind farms are
the appropriate service tenders.

--
Graeme Wall
This account not read.

Graeme Wall <rail@greywall.demon.co.uk> wrote:
> On 01/03/2022 16:54, Recliner wrote:
>> ColinR <rail@greystane.shetland.co.uk> wrote:
>>> On 01/03/2022 10:15, Recliner wrote:
>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>> On 28/02/2022 13:54, ColinR wrote:
>>>>>> On 28/02/2022 13:32, Recliner wrote:
>>>>>>> On Mon, 28 Feb 2022 13:01:56 +0000, Graeme Wall
>>>>>>> <rail@greywall.demon.co.uk> wrote:
>>>>>>>
>>>>>>>> On 28/02/2022 12:42, Recliner wrote:
>>>>>>>>> On Mon, 28 Feb 2022 12:26:34 -0000 (UTC), Sam Wilson
>>>>>>>>> <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>>
>>>>>>>>>> Jeremy Double <jmd.nospam@btinternet.com> wrote:
>>>>>>>>>>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> wrote:
>>>>>>>>>>>> Graeme Wall <rail@greywall.demon.co.uk> wrote:
>>>>>>>>>>>>> On 24/02/2022 08:54, MB wrote:
>>>>>>>>>>>>>> On 24/02/2022 07:40, Graeme Wall wrote:
>>>>>>>>>>>>>>> A opposed to a very large plane ploughing into Sizewell B?
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Aren't the containtment buildings designed with that in mind.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Nuclear power has to build layer up on layer of protection
>>>>>>>>>>>>>> systems which
>>>>>>>>>>>>>> other generations system are not required to have.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Chernobyl, Fukushima, 9 Mile Island…
>>>>>>>>>>>>
>>>>>>>>>>>> <cough> Three Mile Island </cough>
>>>>>>>>>>>>
>>>>>>>>>>>> Chernobyl - fundamentally flawed design driven into unstable
>>>>>>>>>>>> state by badly
>>>>>>>>>>>> executed experiment
>>>>>>>>>>>> Fukushima - possibly unwise location and system design flaws
>>>>>>>>>>>> Three Mile Island - technical design faults and operator error
>>>>>>>>>>>> Windscale extremely dodgy design (in hindsight) which would have
>>>>>>>>>>>> been much,
>>>>>>>>>>>> much worse except for Cockroft’s Folly
>>>>>>>>>>>
>>>>>>>>>>> Yes, but that’s the point.  Not everything works as expected.
>>>>>>>>>>> It’s easy to
>>>>>>>>>>> be wise after the event.  Look up Feynman’s comments about the
>>>>>>>>>>> probability
>>>>>>>>>>> of Space Shuttle failure as quoted by NASA and what the
>>>>>>>>>>> on-the-ground NASA
>>>>>>>>>>> engineers thought the probability of failure was, made when he was
>>>>>>>>>>> on the
>>>>>>>>>>> Challenger enquiry. The
>>>>>>>>>>
>>>>>>>>>> I think my point is that there were specific causes for each of those
>>>>>>>>>> accidents, and the others, which were different; that there’s
>>>>>>>>>> (probably!)
>>>>>>>>>> not a particular systematic flaw in nuclear engineering which causes
>>>>>>>>>> inevitable failures.  It would also be nice to think that engineers
>>>>>>>>>> have
>>>>>>>>>> learned the lessons of each event and will be able to mitigate
>>>>>>>>>> those flaws
>>>>>>>>>> in future, but I’m not in any position to know that.
>>>>>>>>>>
>>>>>>>>>>> Empirical evidence shows that there’s a serious reactor accident
>>>>>>>>>>> somewhere
>>>>>>>>>>> in the world every 10 to 20 years.
>>>>>>>>>>
>>>>>>>>>> Though of course that’s not an inevitable progression.
>>>>>>>>>
>>>>>>>>> In general, newer reactors are safer than older ones of the same
>>>>>>>>> type, as they incorporate the lessons from earlier
>>>>>>>>> failures.
>>>>>>>>
>>>>>>>> I was simply making the point that there was a greater chance of large
>>>>>>>> aircraft crashing into a nuclear power station and causing widespread
>>>>>>>> damage than a VLCC making its way through shallow water to take out a a
>>>>>>>> couple of wind turbines.
>>>>>>>
>>>>>>> I suspect that a crash into a nuclear power was far less likely than a
>>>>>>> large tanker taking out some wind turbines, but
>>>>>>> that the consequences of a reactor pressure vessel failure would be
>>>>>>> far more serious.
>>>>>>>
>>>>>>> Of course, the risks of both of these possible accidents have been
>>>>>>> considered for many years. It's one of the many
>>>>>>> reasons for the extremely strong containment buildings that enclose
>>>>>>> modern reactor vessels.
>>>>>>>
>>>>>>> https://www.nrc.gov/docs/ML0231/ML023180425.pdf
>>>>>>>
>>>>>>> https://hakaimagazine.com/news/designing-against-disaster/
>>>>>>>
>>>>>>>>
>>>>>>>> Arguments about modern nuclear power stations having better protection
>>>>>>>> than earlier ones applies equally to VLCCs.
>>>>>>>
>>>>>>> Does it?
>>>>>>
>>>>>> Yes - when I sailed on VLCCs they were single hulled, now all are double
>>>>>> hulled.
>>>>>>
>>>>>
>>>>> You will know then, what is the chance of a laden VLCC being able to
>>>>> enter waters shallow enough to support a wind farm?
>>>>>
>>>>
>>>> I believe fixed foundation offshore wind turbines can be installed in water
>>>> depths of up to 50m, though of course most wind farms will be in shallower
>>>> water. The largest ULCCs have a draft of about 28m.
>>>>
>>>> So, yes, a fully laden ULCC could theoretically stray into an offshore wind
>>>> farm. Of course, the crew would have to be ignoring their charts and the
>>>> radar to do so, so it would probably only happen if the ship was drifting
>>>> or otherwise out of control.
>>>>
>>>
>>> Whilst true, there are well advanced plans (maybe even actual) for
>>> floating wind turbines - these would, I assume, be able to be moored in
>>> deeper water. But they would present a fairly robust radar echo quite
>>> apart from being charted.
>>>
>>
>> I don't think any floating wind farms are yet in operation, but they're
>> certainly on the way. Not only could they be moored in much deeper water,
>> but they may well be much further offshore, where the winds are stronger
>> and more reliable. So they'll be a greater hazard for shipping.
>>
>> <https://www.ge.com/news/reports/deep-water-wind-these-huge-floating-wind-turbines-could-help-america-meet-its-renewable>
>>
>>
>
> As that article points out, floating gas and oil platforms have been
> around a long time and are, by definition, going to be in seas traversed
> by oil/gas tankers. The only vessels that need to go near wind farms are
> the appropriate service tenders.
>

True.

But I suppose the point is that wind farms occupy large areas (several
square miles), whereas drilling rigs and floating production platforms are
only the size of a small ship.

Roland Perry <roland@perry.co.uk> wrote:
> In message <svl0ir$fl9$1@dont-email.me>, at 11:38:03 on Tue, 1 Mar 2022,
> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> remarked:
>
>> When the Mildenhall KC-135s do racetracks over the North Sea there are
>> rarely any other aircraft visible in attendance.
>
> Do you mean "in attendance and being refuelled"?

I mean visible on FlightRadar24. There are often F-15s, Typhoons and Hawks
shown on FR24 but miraculously they never seem to go near either the
KC-135s or the other tankers while they’re running the racetrack patterns.

> FWIW those tankers frequently fly literally over my house (+/- 50m) and
> the base commander keeps his hand in flying one from time to time. Why
> do I know that - I had lunch with him a few years ago. Hopefully I won't
> now get a visit from any black helicopters (they prefer to use Ospreys)
>
> https://www.youtube.com/watch?v=F9snZJadgkQ

The KC-135s fly over a family member’s house too, but at a considerably
higher altitude. I’ve not seen an Osprey yet.

Sam

--
The entity formerly known as Sam.Wilson@ed.ac.uk
Spit the dummy to reply

On 01/03/2022 10:15, Recliner wrote:
> Of course, the crew would have to be ignoring their charts and the
> radar to do so,

Which happens perhaps not very often but regularly. Been several cases
around here.

On 01/03/2022 17:03, Graeme Wall wrote:
> On 01/03/2022 16:54, Recliner wrote:
>> ColinR <rail@greystane.shetland.co.uk> wrote:
>>> Whilst true, there are well advanced plans (maybe even actual) for
>>> floating wind turbines - these would, I assume, be able to be moored in
>>> deeper water. But they would present a fairly robust radar echo quite
>>> apart from being charted.
>>
>> I don't think any floating wind farms are yet in operation, but they're
>> certainly on the way. Not only could they be moored in much deeper water,
>> but they may well be much further offshore, where the winds are stronger
>> and more reliable.  So they'll be a greater hazard for shipping.
>>
>> <https://www.ge.com/news/reports/deep-water-wind-these-huge-floating-wind-turbines-could-help-america-meet-its-renewable>
>
> As that article points out, floating gas and oil platforms have been
> around a long time and are, by definition, going to be in seas traversed
> by oil/gas tankers. The only vessels that need to go near wind farms are
> the appropriate service tenders.

How far can a floating generator wander? Obviously they'll be tethered,
rather than allowed to drift randomly off into the ocean, but there must
be some scope for moving around from their nominal location.

Certes <none@nowhere.net> wrote:
> On 01/03/2022 17:03, Graeme Wall wrote:
>> On 01/03/2022 16:54, Recliner wrote:
>>> ColinR <rail@greystane.shetland.co.uk> wrote:
>>>> Whilst true, there are well advanced plans (maybe even actual) for
>>>> floating wind turbines - these would, I assume, be able to be moored in
>>>> deeper water. But they would present a fairly robust radar echo quite
>>>> apart from being charted.
>>>
>>> I don't think any floating wind farms are yet in operation, but they're
>>> certainly on the way. Not only could they be moored in much deeper water,
>>> but they may well be much further offshore, where the winds are stronger
>>> and more reliable.  So they'll be a greater hazard for shipping.
>>>
>>> <https://www.ge.com/news/reports/deep-water-wind-these-huge-floating-wind-turbines-could-help-america-meet-its-renewable>
>>>
>>
>> As that article points out, floating gas and oil platforms have been
>> around a long time and are, by definition, going to be in seas traversed
>> by oil/gas tankers. The only vessels that need to go near wind farms are
>> the appropriate service tenders.
>
> How far can a floating generator wander? Obviously they'll be tethered,
> rather than allowed to drift randomly off into the ocean, but there must
> be some scope for moving around from their nominal location.
>

I would assume the power cable back to shore would be a limiting factor.

In message <svm669$naj$1@dont-email.me>, at 22:19:53 on Tue, 1 Mar 2022,
Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> remarked:
>Roland Perry <roland@perry.co.uk> wrote:
>> In message <svl0ir$fl9$1@dont-email.me>, at 11:38:03 on Tue, 1 Mar 2022,
>> Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> remarked:
>>
>>> When the Mildenhall KC-135s do racetracks over the North Sea there are
>>> rarely any other aircraft visible in attendance.
>>
>> Do you mean "in attendance and being refuelled"?
>
>I mean visible on FlightRadar24. There are often F-15s, Typhoons and Hawks
>shown on FR24 but miraculously they never seem to go near either the
>KC-135s or the other tankers while they’re running the racetrack patterns.
>
>> FWIW those tankers frequently fly literally over my house (+/- 50m) and
>> the base commander keeps his hand in flying one from time to time. Why
>> do I know that - I had lunch with him a few years ago. Hopefully I won't
>> now get a visit from any black helicopters (they prefer to use Ospreys)
>>
>> https://www.youtube.com/watch?v=F9snZJadgkQ
>
>The KC-135s fly over a family member’s house too, but at a considerably
>higher altitude. I’ve not seen an Osprey yet.

Looking at FlightRadar24 just now there's an Osprey cruising across
central Cambs at 3,700ft. Can't see any tankers; they'd be at whatever
height that kind of aircraft is, 10 miles from landing.
--
Roland Perry

On Wed, 2 Mar 2022 11:17:39 +0000, Certes <none@nowhere.net> wrote:

>On 01/03/2022 17:03, Graeme Wall wrote:
>> On 01/03/2022 16:54, Recliner wrote:
>>> ColinR <rail@greystane.shetland.co.uk> wrote:
>>>> Whilst true, there are well advanced plans (maybe even actual) for
>>>> floating wind turbines - these would, I assume, be able to be moored in
>>>> deeper water. But they would present a fairly robust radar echo quite
>>>> apart from being charted.
>>>
>>> I don't think any floating wind farms are yet in operation, but they're
>>> certainly on the way. Not only could they be moored in much deeper water,
>>> but they may well be much further offshore, where the winds are stronger
>>> and more reliable.  So they'll be a greater hazard for shipping.
>>>
>>> <https://www.ge.com/news/reports/deep-water-wind-these-huge-floating-wind-turbines-could-help-america-meet-its-renewable>
>>
>> As that article points out, floating gas and oil platforms have been
>> around a long time and are, by definition, going to be in seas traversed
>> by oil/gas tankers. The only vessels that need to go near wind farms are
>> the appropriate service tenders.
>
>How far can a floating generator wander? Obviously they'll be tethered,
>rather than allowed to drift randomly off into the ocean, but there must
>be some scope for moving around from their nominal location.

Very little, I'd have thought. The tethers will partly have the role of keeping them upright in strong winds, so will
have to be taut.

Tweed <usenet.tweed@gmail.com> wrote:
> Certes <none@nowhere.net> wrote:
>> On 01/03/2022 17:03, Graeme Wall wrote:
>>> On 01/03/2022 16:54, Recliner wrote:
>>>> ColinR <rail@greystane.shetland.co.uk> wrote:
>>>>> Whilst true, there are well advanced plans (maybe even actual) for
>>>>> floating wind turbines - these would, I assume, be able to be moored in
>>>>> deeper water. But they would present a fairly robust radar echo quite
>>>>> apart from being charted.
>>>>
>>>> I don't think any floating wind farms are yet in operation, but they're
>>>> certainly on the way. Not only could they be moored in much deeper water,
>>>> but they may well be much further offshore, where the winds are stronger
>>>> and more reliable.  So they'll be a greater hazard for shipping.

>>
>> How far can a floating generator wander? Obviously they'll be tethered,
>> rather than allowed to drift randomly off into the ocean, but there must
>> be some scope for moving around from their nominal location.
>>
>
> I would assume the power cable back to shore would be a limiting factor.
>
>

I mentioned up thread that the Cornish Wave Hub installation that was
intended to allow experimental
wave energy devices to be installed had never been used for that purpose,
it has now been sold to a Swedish Company who hope to use it for floating
wind Turbine generators.
This was the original dream of the hub and shows how the connections to
shore were intended.
<https://www.power-technology.com/projects/cornwallwaveenergyhu/>

The new owners intentions are here,
<
https://w3.windfair.net/wind-energy/news/39576-hexicon-twin-hub-installation-offshore-floating-turbine-celtic-sea-licence-renewable-energy-test-site-global>

I suppose it makes sense to use the existing infrastructure which has yet
to be used , I would imagine any future installations if floating turbines
prove practical and cost effective would use a similar
principle so turbine platforms can be relatively easy disconnected and
taken away for maintenance and repair and another put into place while
that is done.

I don’t think they would want the platforms to range about too far and
would have anchoring systems
that would allow for tidal movement and not much more.

There is a schematic on how it will be tethered on this site

<https://www.theconstructionindex.co.uk/news/view/bechtel-targets-uk-offshore-wind-market>

GH

Recliner <recliner.usenet@gmail.com> wrote:
>
>
> I don't think any floating wind farms are yet in operation, but they're
> certainly on the way. Not only could they be moored in much deeper water,
> but they may well be much further offshore, where the winds are stronger
> and more reliable. So they'll be a greater hazard for shipping.
>
> <https://www.ge.com/news/reports/deep-water-wind-these-huge-floating-wind-turbines-could-help-america-meet-its-renewable>
>
>
>

I suppose the hope of those on the green side trying to establish a new
world order is that
with electric generated by such turbines replacing oil for powering many
things is that if their dream succeeds there will be far less tankers
cruising the oceans anyway.

GH