I recently read in the Washington Post that Heathrow airport asked
airlines to stop selling tickets for summer departures. So if you
don't already have tickets to get to the Worldcon, you'd better get
them quickly, before all airports do the same.

Also, I heard that Heathrow's runways melted during the recent warm
weather there. I don't know if they've solidified again yet. I'm
curious what they're made of. There are plenty of asphalt roads and
sidewalks around here, and they never melt even when the temperature
reaches 40 C (104 F) and they're in direct near-vertical sunlight.
--
Keith F. Lynch - http://keithlynch.net/
Please see http://keithlynch.net/email.html before emailing me.

On Sat, 23 Jul 2022 19:34:21 -0000 (UTC), "Keith F. Lynch"
<kfl@KeithLynch.net> wrote:

>I recently read in the Washington Post that Heathrow airport asked
>airlines to stop selling tickets for summer departures. So if you
>don't already have tickets to get to the Worldcon, you'd better get
>them quickly, before all airports do the same.
>
>Also, I heard that Heathrow's runways melted during the recent warm
>weather there. I don't know if they've solidified again yet. I'm
>curious what they're made of. There are plenty of asphalt roads and
>sidewalks around here, and they never melt even when the temperature
>reaches 40 C (104 F) and they're in direct near-vertical sunlight.

ISTR that in my childhood a few times the asphalt in the street in
front of my house would get soft on some of the hottest days of
summer.

This was in north El Monte, in the San Gabriel valley, east of
Northern Los Angeles.
--

Qualified immunity = virtual impunity.

Tim Merrigan

--
This email has been checked for viruses by AVG.
https://www.avg.com

In article <69lodhpr3gnrbl21e0af7otqck0c0p4c27@4ax.com>,
Tim Merrigan <tppm@ca.rr.com> wrote:
>On Sat, 23 Jul 2022 19:34:21 -0000 (UTC), "Keith F. Lynch"
><kfl@KeithLynch.net> wrote:
>
>>I recently read in the Washington Post that Heathrow airport asked
>>airlines to stop selling tickets for summer departures. So if you
>>don't already have tickets to get to the Worldcon, you'd better get
>>them quickly, before all airports do the same.
>>
>>Also, I heard that Heathrow's runways melted during the recent warm
>>weather there. I don't know if they've solidified again yet. I'm
>>curious what they're made of. There are plenty of asphalt roads and
>>sidewalks around here, and they never melt even when the temperature
>>reaches 40 C (104 F) and they're in direct near-vertical sunlight.
>
>ISTR that in my childhood a few times the asphalt in the street in
>front of my house would get soft on some of the hottest days of
>summer.
>
>This was in north El Monte, in the San Gabriel valley, east of
>Northern Los Angeles.

(Hal Heydt)
It may depend on exact composition and what temperatures the
builders anticipate. I was once in Gila Bend, AZ when it was 111F
at 11 PM (it had been 120F during the day). I've also been in
Marysville, CA when it was 122F. In neither case did the streets
melt.

While 104F (or more) is uncommon where I now live (Vallejo, CA),
it's not unheard of and I've never seen problems with the local
paving due to heat.

On 7/23/2022 4:00 PM, Dorothy J Heydt wrote:
> In article <69lodhpr3gnrbl21e0af7otqck0c0p4c27@4ax.com>,
> Tim Merrigan <tppm@ca.rr.com> wrote:
>> On Sat, 23 Jul 2022 19:34:21 -0000 (UTC), "Keith F. Lynch"
>> <kfl@KeithLynch.net> wrote:
>>
>>> I recently read in the Washington Post that Heathrow airport asked
>>> airlines to stop selling tickets for summer departures. So if you
>>> don't already have tickets to get to the Worldcon, you'd better get
>>> them quickly, before all airports do the same.
>>>
>>> Also, I heard that Heathrow's runways melted during the recent warm
>>> weather there. I don't know if they've solidified again yet. I'm
>>> curious what they're made of. There are plenty of asphalt roads and
>>> sidewalks around here, and they never melt even when the temperature
>>> reaches 40 C (104 F) and they're in direct near-vertical sunlight.
>>
>> ISTR that in my childhood a few times the asphalt in the street in
>> front of my house would get soft on some of the hottest days of
>> summer.
>>
>> This was in north El Monte, in the San Gabriel valley, east of
>> Northern Los Angeles.
>
> (Hal Heydt)
> It may depend on exact composition and what temperatures the
> builders anticipate. I was once in Gila Bend, AZ when it was 111F
> at 11 PM (it had been 120F during the day). I've also been in
> Marysville, CA when it was 122F. In neither case did the streets
> melt.
>
> While 104F (or more) is uncommon where I now live (Vallejo, CA),
> it's not unheard of and I've never seen problems with the local
> paving due to heat.

I remember times in Indiana in the 60s when the asphalt got soft but
didn't really melt. Tires would leave a slight imprint. Guess airplane
tire would have left quite the imprint.

Also remember reading about concrete highways buckling. And they still
are. July 6 in Indiana. https://youtu.be/xasFWwstNoE

In Message-ID:<69lodhpr3gnrbl21e0af7otqck0c0p4c27@4ax.com>,
Tim Merrigan <tppm@ca.rr.com> wrote:

>>Also, I heard that Heathrow's runways melted during the recent warm
>>weather there. I don't know if they've solidified again yet. I'm
>>curious what they're made of. There are plenty of asphalt roads and
>>sidewalks around here, and they never melt even when the temperature
>>reaches 40 C (104 F) and they're in direct near-vertical sunlight.
>
>ISTR that in my childhood a few times the asphalt in the street in
>front of my house would get soft on some of the hottest days of
>summer.

Where the asphalt grows soft in July every year
In the warm summer mornings of [Your state's name here]
from Lou and Peter Berryman's "Your State's Name Here"

On Saturday, July 23, 2022 at 3:34:23 PM UTC-4, Keith F. Lynch wrote:
> I recently read in the Washington Post that Heathrow airport asked
> airlines to stop selling tickets for summer departures. So if you
> don't already have tickets to get to the Worldcon, you'd better get
> them quickly, before all airports do the same.

Gatwick is also limiting flights, though I don't think they've asked airlines
to stop selling tickets yet. Apparently, the flight schedules at airports
assume not all flights were full, so if they are, the passenger processing
at the airport itself is overloaded (especially since the airports are
understaffed).

--
Evelyn C. Leeper

On Saturday, July 23, 2022 at 6:09:19 PM UTC-4, Jay E. Morris wrote:
> I remember times in Indiana in the 60s when the asphalt got soft but
> didn't really melt. Tires would leave a slight imprint. Guess airplane
> tire would have left quite the imprint.

I remember walking out on the runways at Chanute Air Force Base for Armed
Forces Day. If it was hot, the asphalt between the concrete blocks would be
sort of like Play-Dough and when you stepped on it, it would sort of squish
out and only slowly squish back. (I was at an age when that seemed really
cool.) And I weighed a lot less than an airplane. (Then again, this was the
asphalt that separate the blocks and was there to provide a way for them to
expand and contract, so some squishiness was desirable.)

--
Evelyn C. Leeper

--
Evelyn C. Leeper

On 2022-07-23, Keith F. Lynch <kfl@KeithLynch.net> wrote:
> I recently read in the Washington Post that Heathrow airport asked
> airlines to stop selling tickets for summer departures. So if you
> don't already have tickets to get to the Worldcon, you'd better get
> them quickly, before all airports do the same.
>
> Also, I heard that Heathrow's runways melted during the recent warm
> weather there. I don't know if they've solidified again yet. I'm
> curious what they're made of. There are plenty of asphalt roads and
> sidewalks around here, and they never melt even when the temperature
> reaches 40 C (104 F) and they're in direct near-vertical sunlight.

The UK had its first 40C temperatures recently and only for one day.
Asphalt is available in various grades and mixtures tailored for specific
conditions. It's unlikely that any UK road was built with 40C temperatures
in mind.

--
Bernard Peek
bap@shrdlu.com

On 7/23/22 3:34 PM, Keith F. Lynch wrote:
>
> Also, I heard that Heathrow's runways melted during the recent warm
> weather there. I don't know if they've solidified again yet. I'm
> curious what they're made of. There are plenty of asphalt roads and
> sidewalks around here, and they never melt even when the temperature
> reaches 40 C (104 F) and they're in direct near-vertical sunlight.

That sounds like an exaggeration. CBS News has a clickbait headline
saying the heat "melts airport runway" but goes on to say:

"The airport tweeted on Monday that the high temperatures
caused "a surface defect" to be identified on the runway,
later saying that the high surface temperatures had
caused a small section of the surface to lift. Monday was
another day of what the U.K.'s Meteorological Office
identified as "extreme heat," which they attribute to
"exceptional, perhaps record-breaking, temperatures."

https://www.cbsnews.com/news/extreme-heat-in-uk-disrupts-air-travel-melts-airport-runway/

--
Gary McGath http://www.mcgath.com

On 7/23/2022 3:34 PM, Keith F. Lynch wrote:
> I recently read in the Washington Post that Heathrow airport asked
> airlines to stop selling tickets for summer departures.

True:

Heathrow has reduced the number of outbound departures allowed from
104,000 per day to 100,000.

https://www.avweb.com/aviation-news/heathrow-asks-airlines-to-stop-selling-summer-departures/

> Also, I heard that Heathrow's runways melted during the recent warm
> weather there. I don't know if they've solidified again yet. I'm
> curious what they're made of. There are plenty of asphalt roads and
> sidewalks around here, and they never melt even when the temperature
> reaches 40 C (104 F) and they're in direct near-vertical sunlight.

Not exactly:

Luton Airport, not Heathrow, was closed for two hours due to a heat
related issue. Quoting, "A long-standing patch repair to a small
section of the runway - the equivalent of 0.2% of the entire surface
area - became so hot that it de-bonded and began to lift, a spokesperson
for the airport said on Friday, adding it was repaired within two hours.

https://www.reuters.com/world/uk/luton-airport-runway-meltdown-shows-airports-vulnerable-climate-change-2022-07-22/

According to inchem, the melting point of asphalt can range from
54°C to 173°C. The former can easily be reached in direct sun,
but it depends on the exact mix used. The issue at Luton seems
to have been the bonding agent rather than the asphalt itself.

https://inchem.org/documents/icsc/icsc/eics0612.htm

--
Mike Benveniste -- mhb@murkyether.com (Clarification Required)
You don't have to sort of enhance reality. There is nothing
stranger than truth. -- Annie Leibovitz

On Sat, 23 Jul 2022 19:34:21 -0000 (UTC),
Keith F. Lynch <kfl@KeithLynch.net> wrote:
> Also, I heard that Heathrow's runways melted during the recent warm
> weather there. I don't know if they've solidified again yet.

The runways didn't change state. The runways just got a bit too soft to
risk putting heavy planes on them.

Generally the UK has used a different grade of tarmac to hotter places.
I would imagine that it was basically specced and laid when 40C+ (air
temp) was not in the design envelope.

--
Andy Leighton => andyl@azaal.plus.com
"We demand rigidly defined areas of doubt and uncertainty!"
- Douglas Adams

In article <slrntdq2t6.89j.bap@gamma.shrdlu.com>,
Bernard Peek <bap@shrdlu.com> wrote:
>On 2022-07-23, Keith F. Lynch <kfl@KeithLynch.net> wrote:
>> I recently read in the Washington Post that Heathrow airport asked
>> airlines to stop selling tickets for summer departures. So if you
>> don't already have tickets to get to the Worldcon, you'd better get
>> them quickly, before all airports do the same.
>>
>> Also, I heard that Heathrow's runways melted during the recent warm
>> weather there. I don't know if they've solidified again yet. I'm
>> curious what they're made of. There are plenty of asphalt roads and
>> sidewalks around here, and they never melt even when the temperature
>> reaches 40 C (104 F) and they're in direct near-vertical sunlight.
>
>The UK had its first 40C temperatures recently and only for one day.
>Asphalt is available in various grades and mixtures tailored for specific
>conditions. It's unlikely that any UK road was built with 40C temperatures
>in mind.

One might suppose that that will change, going forward.

Dorothy J Heydt <djheydt@kithrup.com> wrote:
> In article <slrntdq2t6.89j.bap@gamma.shrdlu.com>,
> Bernard Peek <bap@shrdlu.com> wrote:
>>On 2022-07-23, Keith F. Lynch <kfl@KeithLynch.net> wrote:
>>> I recently read in the Washington Post that Heathrow airport asked
>>> airlines to stop selling tickets for summer departures. So if you
>>> don't already have tickets to get to the Worldcon, you'd better get
>>> them quickly, before all airports do the same.
>>>
>>> Also, I heard that Heathrow's runways melted during the recent warm
>>> weather there. I don't know if they've solidified again yet. I'm
>>> curious what they're made of. There are plenty of asphalt roads and
>>> sidewalks around here, and they never melt even when the temperature
>>> reaches 40 C (104 F) and they're in direct near-vertical sunlight.
>>
>>The UK had its first 40C temperatures recently and only for one day.
>>Asphalt is available in various grades and mixtures tailored for specific
>>conditions. It's unlikely that any UK road was built with 40C temperatures
>>in mind.
>
> One might suppose that that will change, going forward.

Maybe, maybe not...it really depends on how the impact, or the perceived
impact, of not doing it compares to the cost. Maybe they change it the next
time the surface is redone. Maybe they don't do it at all and cancel/delay
flights.
It's a lot like the "design for peak" and "100% uptime" problems in IT.
A customer (internal or otherwise) says it's critical that their application
be "100% available" and "never slow down", so we design for that (well,
five or six nines instead of 100%) and tell them the cost. It usually (well,
always so far) turns out that they're willing to tolerate some downtime and
some slowness.

Robert
--
Robert K. Shull Email: rkshull at rosettacon dot com

On Mon, 25 Jul 2022 18:45:44 -0000 (UTC), rkshullat@rosettacondot.com
wrote:

>Dorothy J Heydt <djheydt@kithrup.com> wrote:
>> In article <slrntdq2t6.89j.bap@gamma.shrdlu.com>,
>> Bernard Peek <bap@shrdlu.com> wrote:
>>>On 2022-07-23, Keith F. Lynch <kfl@KeithLynch.net> wrote:
>>>> I recently read in the Washington Post that Heathrow airport asked
>>>> airlines to stop selling tickets for summer departures. So if you
>>>> don't already have tickets to get to the Worldcon, you'd better get
>>>> them quickly, before all airports do the same.
>>>>
>>>> Also, I heard that Heathrow's runways melted during the recent warm
>>>> weather there. I don't know if they've solidified again yet. I'm
>>>> curious what they're made of. There are plenty of asphalt roads and
>>>> sidewalks around here, and they never melt even when the temperature
>>>> reaches 40 C (104 F) and they're in direct near-vertical sunlight.
>>>
>>>The UK had its first 40C temperatures recently and only for one day.
>>>Asphalt is available in various grades and mixtures tailored for specific
>>>conditions. It's unlikely that any UK road was built with 40C temperatures
>>>in mind.
>>
>> One might suppose that that will change, going forward.
>
>Maybe, maybe not...it really depends on how the impact, or the perceived
>impact, of not doing it compares to the cost. Maybe they change it the next
>time the surface is redone. Maybe they don't do it at all and cancel/delay
>flights.
>It's a lot like the "design for peak" and "100% uptime" problems in IT.
>A customer (internal or otherwise) says it's critical that their application
>be "100% available" and "never slow down", so we design for that (well,
>five or six nines instead of 100%) and tell them the cost. It usually (well,
>always so far) turns out that they're willing to tolerate some downtime and
>some slowness.
>
> Robert

Reminds me of the engineers' credo: You can have it fast, good, and
cheep, pick any two.
--

Qualified immunity = virtual impunity.

Tim Merrigan

--
This email has been checked for viruses by AVG.
https://www.avg.com

In article <tbmoco$ho12$1@memoryalpha.rosettacon.com>,
<rkshullat@rosettacondot.com> wrote:
>It's a lot like the "design for peak" and "100% uptime" problems in IT.
>A customer (internal or otherwise) says it's critical that their application
>be "100% available" and "never slow down", so we design for that (well,
>five or six nines instead of 100%) and tell them the cost. It usually (well,
>always so far) turns out that they're willing to tolerate some downtime and
>some slowness.

(Hal Heydt)
For the applications system I maintain and run (ConReg for
DunDraCon), it turns out to be easy, and inexpensive, to
sufficiently overprovision to come very close to 100%
availablility. At least, within the system. Can't do much other
than shut down graccefully if the power goes out (everything has
a UPS for short term power). I carry enough spare
parts--routers, cables, etc.--to replace anything that fails.
The system runs a replicated database, so if the primary server
fails, one can log into the secondary and keep going. The
servers are Raspberry Pi 4 B, 4GB plus an attached 128GB SSD.

If I had an unlimited budget, I would look into fuel cell standby
power units and aim for run time with power utility out of 6
hours. If I could get it to 12 hours, I could carry spare
Hydrogen tanks and run an entire con with no power from the wall.

In article <isrtdh5peq80kl2f6nkdo4s81slql67s4l@4ax.com>,
Tim Merrigan <tppm@ca.rr.com> wrote:
>Reminds me of the engineers' credo: You can have it fast, good, and
>cheep, pick any two.

(Hal Heydt)
I oncce knew a contract programmer who kept a sign to that effect
up over his desk. I told him he was an optimist.

On 2022-07-25, Dorothy J Heydt <djheydt@kithrup.com> wrote:
> In article <isrtdh5peq80kl2f6nkdo4s81slql67s4l@4ax.com>,
> Tim Merrigan <tppm@ca.rr.com> wrote:
>>Reminds me of the engineers' credo: You can have it fast, good, and
>>cheep, pick any two.
>
> (Hal Heydt)
> I oncce knew a contract programmer who kept a sign to that effect
> up over his desk. I told him he was an optimist.

I got a job because at the interview I handed the programme manager a
diagram showing a triangle with better, faster, cheaper at the corners. I
asked him to put an X somewhere inside the triangle to establish priorities.

--
Bernard Peek
bap@shrdlu.com