Images of shuttle being prepared for launch

[Sisyphus]

The url below is a PowerPoint slide show on processing of the Shuttle. It has some excellent images and offers a perspective you may not have seen before.

http://www.novac.com/resources/pjohnson/discovery-prelaunch-processing.pps

[wshngtn1]

Wow - cool pics. Thanks for posting. I'm sure it is unbelievable the amount of things they do before launching one of those puppies.

[Zguy28]

That's a cool show. I have coworkers who work at KSC.

[mjah]

Awesome.

But why didn't they show the step of putting the payload into the cargo bay once the Shuttle is on the pad? I was looking forward to that.

Imagine how cool it will be when we have spacecraft that actually go places and discover things!

[Sisyphus]

Awesome.

But why didn't they show the step of putting the payload into the cargo bay once the Shuttle is on the pad? I was looking forward to that.

Imagine how cool it will be when we have spacecraft that actually go places and discover things!

The payload goes in at different times, from what I understand. Some goes in horizontally, some that is designed to support itself only vertically gets installed in the VAB, and some that is temperature sensitive or involves biological material can get put in when the shuttle is already on the launch pad ready for lift off.

I think the pic of the technician astride the engine as ii is installed in the shuttle is cool.:cool:

[More Complete]

I've always wondered what happens to those big fuel tanks when they drop off? Do they just sink to the bottom of the ocean or what?

[Larry]

I was surprised they loaded the payload on the pad, myself.

Anything that goes into the shuttle has to be able to take 3G "positive x" acceleration. (And a lot of vibration, too.) (And, also obviously, the shuttle has to be strong enough to support three times the payload's weight.)

So I have trouble believing that there's anything in most payload that couldn't be loaded when the shuttle is sitting on it's wheels. (And it sure looks to me like it'd be logistically easier to load it in that orientation.)

I can certainly see why they'd occasionally need the ability to access the payload bay on the pad. It just doesn't seem to make sense to me for them to do it that way with the entire payload.

[Larry]

I think the pic of the technician astride the engine as ii is installed in the shuttle is cool.:cool:

What caught my attention in that pic was the notation on the adjacent SSME's cover, warning that it was an "O2 deficient area". Both because I'd certainly hope that nobody's going to remove that cover unless they know what they're doing, and because I wonder why it would be "O2 deficient". Do they fill the nozzle with Nitrogen or some such to prevent corrosion? (And if so, then how do they prevent the outside from corroding? And is that cover so airtight that the Nitrogen or whatever doesn't leak out, or do they just keep supplying it with Nitrogen for six months or however long it takes to get ready for launch?)

[Sisyphus]

What caught my attention in that pic was the notation on the adjacent SSME's cover, warning that it was an "O2 deficient area". Both because I'd certainly hope that nobody's going to remove that cover unless they know what they're doing, and because I wonder why it would be "O2 deficient". Do they fill the nozzle with Nitrogen or some such to prevent corrosion? (And if so, then how do they prevent the outside from corroding? And is that cover so airtight that the Nitrogen or whatever doesn't leak out, or do they just keep supplying it with Nitrogen for six months or however long it takes to get ready for launch?)

I'll go back and look at it later ... but rather than corrosion prevention it may be due to cryogenics being used. The presence of liquid nitrogen can cause oxygen deficiency and if you were in an enclosed space that may not be good

[Sisyphus]

I was surprised they loaded the payload on the pad, myself.

Anything that goes into the shuttle has to be able to take 3G "positive x" acceleration. (And a lot of vibration, too.) (And, also obviously, the shuttle has to be strong enough to support three times the payload's weight.)

So I have trouble believing that there's anything in most payload that couldn't be loaded when the shuttle is sitting on it's wheels. (And it sure looks to me like it'd be logistically easier to load it in that orientation.)

I can certainly see why they'd occasionally need the ability to access the payload bay on the pad. It just doesn't seem to make sense to me for them to do it that way with the entire payload.

Someone with inside knowledge said the following:

"Some payloads are bolted into the payload bay in the orbiter processing facility (horizontal) or in the vehicle assembly building (vertical). If a payload needs special attention then it is put into the payload carrier and transfered to the vehicle on the pad. The large white container is not put into the payload bay, only its contents are transfered over.

For example, a payload may be attached at the pad if it has consumables that are loaded at the last minute (cryogenics or life sciences stuff). or if it is very sensitive to environmental factors such as temperature or humidity. or if it can only support its own weight while in the vertical orientation.

The orbiter payload bay has several hard attach points or trunions to which large payloads are bolted. in addition, several smaller payloads can be attached to carriers that are then attached to the trunions. Payloads can be anything from the size of a small wastebasket (a get-away special or GAS canister) to the size of the whole bay (such as hubble or spacehab). The carriers can also be used to attach cryogenic tanks that allow extended duration missions up to 20 days long.

The placement of the payload in the bay is really critical because it determines the center of gravity of the vehicle. The CG has to be just so for launch and landing and it can't change much if a payload is ejected during the mission or if the orbiter has to perform an abort landing. CG affects the stability of the control system, thermal load on the tiles and control surfaces, cross range capability, glide slope, etc. It takes forever to plan that stuff. It's a good reason why it makes sense for launch vehicles to be rockets and capsules and not flying vehicles.

Some of the most impressive things I've saw in my years on shuttle were the out-of-the ordinary repairs such as replacing auxiliary power units, fuel cells and engines on the pad. This is really difficult. Imagine standing your car on end and trying to replace the engine. Crazy. "

[Sisyphus]

I've always wondered what happens to those big fuel tanks when they drop off? Do they just sink to the bottom of the ocean or what?

Nope ... they are recovered.

http://www.nasa.gov/mission_pages/shuttle/behindscenes/recovery_ships.html

[Larry]

Nope ... they are recovered.

Uh, no, the SRBs are recovered.

Then they're broken down into smaller segments, and the segments are shipped to Utah, re-loaded with solid propellant, shipped back to the cape, and then re-assembled into a single rocket. This was done because one of the Senators on the appropriations committee was from Utah. This is also why the SRBs have o-rings. (Remember o-rings? The Challenger blew up because the o-rings failed.) The o-rings seal the joints that wouldn't be there if it hadn't been for a Senator's demand for pork.

(Curiously, when Congress investigated the Challenger explosion, they didn't notice this.)

It's also been reported that, if the SRBs were made at the Cape, as a single casting, just like every other solid rocket the US has ever made, (and not one of which has ever failed), then it would actually be cheaper to make a new one for every launch than it costs to re-use them.

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The ET is deliberately dumped into the Indian ocean. (Theoretically, it breaks up on re-entry, but it's aimed at the Indian Ocean just in case it doesn't.)

There are some interesting things about this operation.

It actually costs the shuttle fuel to aim them into the ocean. They could simply deliver them to orbit for less fuel, but at shuttle-orbit altitudes, they wouldn't stay up for long, and NASA doesn't want the papers to be full of "What if it lands on Moscow?" speculation.

A lot of space enthusiasts tried to come up with potential uses for ETs in orbit. It's big, empty, it's capable of holding an atmosphere against vacuum. It has a hatch in the nose that's big enough to admit a man in a space suit. (I'm going from memory, from things I read a few years after the shuttle first flew. It's possible that some of the things I "know" have changed since then.)

But NASA is required by law to provide launch services at cost.

Since the ET is a leftover by-product from a shuttle launch, and since it actually uses less fuel to orbit them than it costs to get rid of them, this would have resulted in NASA having to pay the Trekkies to take the things.

Congress decided to fix this problem, by making it illegal for NASA to deliver ETs into orbit.