Shuttle redux, a simple plan [KISS principle]

Self

[det dweller too]

As the information unfolds on the causes of the shuttle disaster, it is becoming likely that the left wing may have been damaged by ice/foam/whatever falling off the main tank at liftoff.

[det dweller too]

A simple way to protect the ceramic tiles from damage during liftoff, and even from meteors while in orbit, is to spray on a few inches of that structural foam on top of the tiles. Perhaps even add a harder thin second coat of tough plastic. This will protect the tiles from any damage prior to starting re-entry. During re-entry this foam anf plastic willl vaporize in a few seconds leaving the tiles to do their job undamaged. This idea should be doable at a very reasonable cost and will protect a major vulnerability of the tiles.
Comments?

[dirtboy]

This idea should be doable at a very reasonable cost and will protect a major vulnerability of the tiles. Comments?

Yes. This would change the aerodynamic properties of the wings in unpredictable, uncontrollable ways. All it takes is for a few unburned patches of the material to remain to make it very difficult to control the trim of the shuttle during re-entry.

I've seen a hard shield over key areas proposed that could be jettisoned, but that in turn could cause damage as it was jettisoned, along with leaving vulnerable points where it connects to the shuttle.

[RightWhale]

Look at the old DynaSoar project: a small shuttle mounted on top of the booster where nothing can strike the orbiter during launch. Heavy cargo can be launched by itself on big boosters without worrying about crew safety.

[narby]

Would work, but be very heavy. Even a coat of paint on something the size of the shuttle is hundreds of pounds.

And my theory, which I'm trying to get out, is that the doors were damaged where the attachments to the External Tank are made. There are several of these, and they MUST be closed after the ET is released.

I think these doors are hanging out in the breeze, and could easily have been damaged, or the space under them filled with foam trash.

[My2Cents]

Thanks for the reminder of this project. Another '60s space project that probably should have been implemented.

[Wright is right!]

"Would work, but be very heavy. Even a coat of paint on something the size of the shuttle is hundreds of pounds."

Which is why American Airlines doesn't paint its planes. Carrying around the weight of the paint eats up (some) fuel. American took it a step further when the No Smoking rule took effect. Someone added up all the weight of the seat-arm ash trays and calculated how much fuel would be used by the entire fleet to carry around the ash trays. It was some seemingly insignificant amount, but added up fleet-wide over the course of a year. So they had the cabin crew yank and discard all the ashtrays.

Michael

[chimera]

Some are thinking along those lines. A smaller re-usable for manned flights with only passengers, and cargo being hauled up on bigger expendables. The idea of the shuttle was to have a flexible system that could do both. Then you have capabilities like Spacelab and the like. With the dual system, you'd have to put up the lab and leave it up there, and go with the reusable to return people and limited amounts of payload. Then you'd have the cost of those expendable boosters. The folks selling the re-usable concept back in the late sixties used to use pictures of the Saturn V as a whipping boy. Why spend all that money on a one-shot booster? Maybe we're going back to the future here...?

[RightWhale]

It was dumped in favor of the one I worked on, which was dumped in turn.

[RightWhale]

Then you'd have the cost of those expendable boosters.

There are designs that make the expendable boosters into recoverable and reusable boosters. They aren't as efficient as rockets, but cost is another factor.

[Blood of Tyrants]

That is what I mentioned earlier. A much smaller version of the space shuttle that has just enough room on it for the atronauts. Leave the heavy lifting up to the unmanned rockets. Make the pilots chauffeurs instead of truck dtivers.

[My2Cents]

Personally, I think this is a great plan. Perhaps the US needs a new fleet of heavy-lift rockets to get large payloads into space. Look at the "Progress" module (I think the Russians call it) -- it remotely docks with the ISS. They don't even need astronauts to maneuver and "drive" this cargo vessel around. Some at NASA have suggested perpetually orbiting "space trucks" that are similar, I guess, to train engines that move boxcars around a rail yard. These could be piloted by astronauts to move large pre-fabricated space material into proper orbit, or to add to the construction of the space station. Why not make the space station the platform for all our space commerce? Expand it; add a "wing" as a base for astronauts to embark on other orbital missions, but ferrying them into and out of orbit should be by a simple (relatively speaking) space plane, something like Dyna-Soar.

This would require a major increase in NASA's budget, but frankly, I think the space program is one of the very few things the federal government does that is actually worth spending money on.

[SteveH]

At this point the only thing that would make a drastic improvement, I think, would be going to titanium.

That would be expensive, and possibly more expensive than more system-wide alternatives.

System wide alternatives would include I would think a robotic shuttle (original shuttle concept was criticized for missing this possibility, if I recall correctly).

As a stopgap systemwide alternative, one idea I would think would be to have a linkup capability and a Soyuz on hot standby. This presumes loading the passengers into the Space Station is not feasible due to supply limitations (also, if the shuttle is incapacitated, it might not be able to rendezvous with the Space Station).

I wonder if the unmanned Soyuz launch was designed to be a day later than Columbia scheduled touchdown due to the remote possibility that a rendezvous and rescue attempt might have been called for (had NASA diagnosed a problem with Columbia while still in orbit).

[Paleo Conservative]

What about using parts from the shuttle program to build a heavy lift booster. I would think equipment capable of using existing shuttle infrastructure would be fairly inexpensive and quick to develop especially since quite a bit of work has already been done designing such equipment.

[chimera]

So this looks like the shuttle except there is a sausage where the orbiter would go. What parts would you get back? Looks like those are the same SRBs. The sausage looks like it has the shuttle's main engines. You'd want those back. Does the sausage come back intact or just the engine pods? How do they survive reentry? Are we talking tiles again?

Looks like you've got everything there except a manned system. That saves costs and reduces risk of loss of life, but are we talking about an unmanned space program?

[Paleo Conservative]

Does the sausage come back intact or just the engine pods?

From what I have read, only the engines would come back. There are a couple of advantages to leaving the cannister in space. One is that you don't waste power launching mass that has to return to Earth. The "sausage" doesn't have to have the extra weight of heat shields to reenter the atmosphere.

The space shuttle weighs about 250,000 pounds plus it can carry a cargo of 50,000 to 60,000 pounds. If the space shuttle SRBs, fuel tank, and main engines were used to send up a non-returnable payload, NASA could launch 300,000 pounds of cargo into orbit in one launch. That means one cargo mission could replace six manned launches to supply the International Space Station. When you consider that we are averaging a shuttle lost per 50 missions, and the space station is expected to take 50 space shuttle missions, it is quite probable we could lose aother shuttle just hauling up modules for the space station.

Instead of risking 50 crews lifting modules up to the space station we could haul up the same equipment in six or seven cargo missions with hardware that we already have.

[det dweller too]

"This would change the aerodynamic properties of the wings in unpredictable, uncontrollable ways. All it takes is for a few unburned patches of the material to remain to make it very difficult to control the trim of the shuttle during re-entry."

Yes, and that is why I suggested that structural foam. If you ever saw that stuff burn it is amazing! It seems to vaporize. It will disappear completely at a fairly modest temperature, such that there will be nothing left of it long before it runs into any significant atmosphere. It might even need the second, harder outer coat to make it through takeoff. The big benefit is keeping the tiles covered and undamaged until they will be used and then completely disappearing long before the temperature gets high.

[chimera]

So you have a detachable engine pod in some kind of re-entry survivable form? That sounds a little tricky, but perhaps not unmanageable. You'd have pyrotechnics separate the engine pods from the cargo cannister, then some kind of enclosable heat shield to surround the engines and their nozzles. I guess a super heavy-duty parachute pack to get them down gently. You'd have to have some kind of retropack and alignment system on the engine pods to get the retros pointed in the right direction to de-orbit them.

No question something is going to have to be done to enhance the shuttle fleet survivability if NASA wants to stick with it. These things were designed to be used 100 times. Columbia made it to a quarter of that, Challenger even less. We're going to run out of these things if this keeps up. And I can't see Congress appropriating and more funds to build more orbiters that keep getting lost when the whole idea was that they would not be lost. Too much pressure to spend money elsewhere (e.g., entitlements).

[Paleo Conservative]

And I can't see Congress appropriating and more funds to build more orbiters that keep getting lost when the whole idea was that they would not be lost.

My approach would do away with the need for more orbiters while at the same time utilizing the infrastructure already in place for the shuttle program. In the near term we need to fix the safety problems of the shuttle. In the longer term, we need to get new hardware for getting humans to and from low Earth orbit, prerfably a system owned and operated by the private sector. NASA ought to be a research agency not a glorified trucking company.

[Lurking2Long]

I had the very same thought about an hour ago...I also replied on one thread that a thin, strong lightweight netting over the upper half or so of the tank would help minimize "shedding".

[boris]

"So you have a detachable engine pod in some kind of re-entry survivable form?"

Dunking SSMEs into salt water voids the warranty. You'd have to seal them somehow in a water-tight way.

--Boris