SLS launched this morning. It was spectacular. NASA showed us again that
they really know how to run a boondoggle.

Alain Fournier

On 2022-11-16 6:04 AM, Alain Fournier wrote:
> SLS launched this morning. It was spectacular. NASA showed us again that
> they really know how to run a boondoggle.
>
>
> Alain Fournier

*snicker*

The point I think, as was pointed out to me elsewhere, is that getting
SLS off the pad now enables Starship/SuperHeavy to perform either an
orbital or sub-orbital test without any political road-blocks being
thrown in its way to prevent an embarrassment to NASA.

I'm happy SLS got off the ground. I'd be even more happy if it were
reconfigured to deliver cargo only and we could use up the supply of
this expensive, ill-conceived rocket to put one and done cargo into
space. Perhaps in either lunar or Lagrange Point orbits.

Not a big fan of the gateway/toll-booth either....

Dave

On 11/16/22 3:04 AM, Alain Fournier wrote:
> SLS launched this morning. It was spectacular. NASA showed us again that
> they really know how to run a boondoggle.
>
> Alain Fournier

Are those center tanks painted red, or do they rust quickly?

Trolidan7 submitted this gripping article, maybe on Saturday:
> On 11/16/22 3:04 AM, Alain Fournier wrote:
>> SLS launched this morning. It was spectacular. NASA showed us again that
>> they really know how to run a boondoggle.
>>
>> Alain Fournier
>
> Are those center tanks painted red, or do they rust quickly?

The foam insulation on the core stage gets a suntan, just like the
Shuttle's external tanks did.

/dps

--
Killing a mouse was hardly a Nobel Prize-worthy exercise, and Lawrence
went apopleptic when he learned a lousy rodent had peed away all his
precious heavy water.
_The Disappearing Spoon_, Sam Kean

On Nov/20/2022 at 02:50, Snidely wrote :
> Trolidan7 submitted this gripping article, maybe on Saturday:
>> On 11/16/22 3:04 AM, Alain Fournier wrote:
>>> SLS launched this morning. It was spectacular. NASA showed us again
>>> that they really know how to run a boondoggle.
>>>
>>> Alain Fournier
>>
>> Are those center tanks painted red, or do they rust quickly?
>
> The foam insulation on the core stage gets a suntan, just like the
> Shuttle's external tanks did.

To be more precise. The natural colour of the insulation foam is light
orange. After exposition to sunlight, it becomes a darker rusty colour
(what Snidely called a suntan).

Alain Fournier

On 17/11/2022 11:49 pm, David Spain wrote:

> I'm happy SLS got off the ground. I'd be even more happy if it were
> reconfigured to deliver cargo only and we could use up the supply of
> this expensive, ill-conceived rocket to put one and done cargo into
> space. Perhaps in either lunar or Lagrange Point orbits.
>
> Not a big fan of the gateway/toll-booth either....
>
> Dave
>

I seem to remember the USAF [*] doing a study that showed that a solid
rocket failure after lift-off could be unsurvivable because bits of
burning solid rocket fuel would destroy the capsule's parachutes. I
don't believe a solution was found.

So relegating it to cargo only would certainly make sense, if there
really is no cheaper alternative available.

Sylvia.

[*] Yes - I don't know why the USAF was doing that either.

On 11/20/22 5:38 AM, Alain Fournier wrote:
> On Nov/20/2022 at 02:50, Snidely wrote :
>> Trolidan7 submitted this gripping article, maybe on Saturday:
>>> On 11/16/22 3:04 AM, Alain Fournier wrote:
>>>> SLS launched this morning. It was spectacular. NASA showed us again
>>>> that they really know how to run a boondoggle.
>>>>
>>>> Alain Fournier
>>>
>>> Are those center tanks painted red, or do they rust quickly?
>>
>> The foam insulation on the core stage gets a suntan, just like the
>> Shuttle's external tanks did.
>
> To be more precise. The natural colour of the insulation foam is light
> orange. After exposition to sunlight, it becomes a darker rusty colour
> (what Snidely called a suntan).
>
>
> Alain Fournier

Am I mistaken or did they used to be lighter in
color?

Was the composition of the insulation foam changed
at some point in time?

Are the tanks stored longer now than earlier before
they are used?

Trolidan7 blurted out:
> On 11/20/22 5:38 AM, Alain Fournier wrote:
>> On Nov/20/2022 at 02:50, Snidely wrote :
>>> Trolidan7 submitted this gripping article, maybe on Saturday:
>>>> On 11/16/22 3:04 AM, Alain Fournier wrote:
>>>>> SLS launched this morning. It was spectacular. NASA showed us again that
>>>>> they really know how to run a boondoggle.
>>>>>
>>>>> Alain Fournier
>>>>
>>>> Are those center tanks painted red, or do they rust quickly?
>>>
>>> The foam insulation on the core stage gets a suntan, just like the
>>> Shuttle's external tanks did.
>>
>> To be more precise. The natural colour of the insulation foam is light
>> orange. After exposition to sunlight, it becomes a darker rusty colour
>> (what Snidely called a suntan).
>>
>>
>> Alain Fournier
>
> Am I mistaken or did they used to be lighter in
> color?

All depends on how long a tank has been in the sun. Some had short
exposure, some had long (and multiple trips on the causeway).

> Was the composition of the insulation foam changed
> at some point in time?

I believe the answer is "yes", but it is in the same family of
plastics. The UV behavor is very similar. I'm not going to go back
through the NasaSpaceFlight.com [NSF] streams of rollouts to track down
the quote, and you may be better off looking at the media packets NASA
has prepared.

> Are the tanks stored longer now than earlier before
> they are used?

Being stored indoors would not result in much discoloration.

This tank has spent a lot of time on stands and pads. Remember that it
dd 2 attempts at the full-duration static fire, and has rolled out on
the mobile launch pad 3 or 4 times and was out at 39B long enough to
hook up connections, do inspections, run the tests (full wet dress is a
4 day event, AIUI), and then for each roll back there's undoing all the
connections.

Consider also that Shuttles were often on the pad for months during
their flight preparations, and the tank color would change during that
time. There's a ewetoob vid of the rollout for STS-133, on Sep 23,
2010, according to the tag. Launch was February 24, 2011.

/dps

--
Who, me? And what lacuna?

On 2022-11-20 9:09 PM, Sylvia Else wrote:
> On 17/11/2022 11:49 pm, David Spain wrote:
>
>> I'm happy SLS got off the ground. I'd be even more happy if it were
>> reconfigured to deliver cargo only and we could use up the supply of
>> this expensive, ill-conceived rocket to put one and done cargo into
>> space. Perhaps in either lunar or Lagrange Point orbits.
>>
>> Not a big fan of the gateway/toll-booth either....
>>
>> Dave
>>
>
> I seem to remember the USAF [*] doing a study that showed that a solid
> rocket failure after lift-off could be unsurvivable because bits of
> burning solid rocket fuel would destroy the capsule's parachutes. I
> don't believe a solution was found.
>

That was for the "Liberty" Constellation configuration, aka Ares I aka
'The Stick'. This was a single 5 segment SRB with a TBD second stage to
boost the Orion Capsule into LEO only. I believe the original plan
called for the second stage to use LH2/LO2 and a modified J-2 rocket
engine first used on the upper stages of the
Saturn V and to be called the J-2X. However, the J-2X eventually ended
up being a 'clean-sheet' design and did not evolve from the J2 due to
performance requirements needed for the Ares I/V program.

Constellation was cancelled by the Obama Administration and I believe
the J2-X died with it along with Ares I. Ares V moved on to morph into
the SLS. SLS upper stage currently is the DCSS (Delta Cryogenic Second
Stage) to eventually be replaced by the ESA developed Exploration Upper
Stage EUS. The latter will extend the SLS in height requiring a new
launch tower to accommodate it. It's in the works as they say, even if
it tilts slightly off-center (or at least it used to)!.

The AF range safety folks based out of Patrick AFB at the Cape did a
study which suggested the LAS system for the Orion capsule on an Ares I
would not be able to boost it beyond the debris field should the SRB
explode or be launch destructed via side splitting munitions on the way
up. Flaming segments of solid fuel could melt the nylon parachute
material used to make up the Orion parachutes should the capsule fall
through this debris field. I believe there are videos available of a
Delta II explosion that used SRBs that show the effect of this flaming
debris quite nicely. Here's one from Scott Manley:

https://youtu.be/ey-bbM7m1L8

I don't know what analysis was done for SLS. Perhaps the abort plan is
to jettison the SRBs and remain on the core booster long enough to fly
clear any SRB debris? If the core booster goes first maybe it is just as
risky? I don't know.

Liberty flew exactly once. Uncrewed, with dummy payload simulators for
the capsule and upper-stage. As NASA PAO said at the time: "Testing new
concepts in space exploration..."

> So relegating it to cargo only would certainly make sense, if there
> really is no cheaper alternative available.
>
> Sylvia.
>

There is, but might as well leverage sunk cost if you can.

> [*] Yes - I don't know why the USAF was doing that either.They are responsible for range safety at the Cape.

Dave