If the space shuttle crew suddenly got the urge to do something crazy, do they have enough autonomy and resources to do a lunar fly-by or other suitably impressive stunt? Would such stunts be survivable, ending in an earth orbit suitable for safe re-entry and landing with enough life support and power to do so?
No way do they have the resources to climb far enough the gravity well to do a lunar flyby.
I very strongly suspect that they have negligible autonomy for doing anything ( I don’t know it for a fact, but were I running the program, they certainly wouldn’t) ANY resources hauled into orbit are precious, and expensive, and you need it for maneuvering and re-entry. Eart5h Orbit is no place to screw around with essential resources.
The Space Shuttle isn’t capable of reaching the Moon, not anywhere close to it. The fuel for the main engines is held in the external fuel tank, which is dropped. I’m not sure if they have any residual fuel at at all for the main engines. Mainly they only have manuevering engines that could only slightly change their orbit.
They could probably alter their re-entry to buzz your house, but that’s about it…
And then they’d drill spectacularly into the ground a couple miles over. The orbiter is a brick with wings - essentially the world’s biggest glider. Whatever airspeed they consume on executing such a stunt will not be recoverable as they don’t have engines for operation in Earth atmosphere, so they would be unable to climb and carry on to the proper landing strip.
On the last shuttle mission, they did an impromptu fly around of the space station to check the damage on the solar arrays. This was supposed to be done with a guidance computer (or some semi-autonomous means), but that system was down and the pilot had to do the manuever manually. This was a semi-big deal.
They have some residual fuel for the main engines as they need that for their de-orbit burn, and the main tank isn’t completely empty when it’s dropped.
They could, quite easily, alter the drop point of the tank so that instead of spashing down in the ocean, it hits land. Most of the tank would be burned up, but still the rain of debris would make for a very bad day for anyone underneath it.
No, the deorbit burn is done by the OMS. The main engines run on liquid helium and liquid oxygen, and there’s none of that stored in the orbiter.
Basically, the Shuttle needs to be launched into the intended orbit from the very beginning. The OMS is used for orbital corrections, but its abilities are very limited. If the Shuttle is launched to rendezvous with Hubble, it can’t even get to the International Space Station.
Didn’t know that stuff burned. :smack: 
Besides not having any fuel, the main engines are not designed to support an in-flight restart.
The Shuttle Main Engines are fed from the LO2 and LH2 reservoirs in the External Tank; the Shuttle Orbiter itself has no internal cryogenic fuel storage, just motors and feed turbopumps. Although the SMEs are technically restartable, this has never been done in operation for obvious reasons, and the feed delivery system isn’t even design to do this, even if you placed fuel and oxidizer tanks in the payload bay. De-orbit maneuvers are performed with the Orbital Maneuvering System (OMS), which along with the Reaction Control System (RCS), usesstorable monomethyl hydrazine (MMH) fuel and nitrogen tetraoxide (N2O4) oxidizer. Each OMS engine (there are two pods) produces approximately 6,000 lbf of thrust at full chamber pressure (125 psiz) and a specific impulse of 313 seconds in vacuum.
Main tank separation is normally governed by the automatic ascent sequence; if an abort profile is selected then the abort program should perform the valve closure and tank separation sequence. Although I don’t have anything in front of me that specifically says that there is not a manual override for tank separation, I can’t think of a compelling reason why such an option would be available to the crew; in a Return-To-Launch-Site (RTLS) abort sequence there are several hundred actions that have to occur in a sequence of a few seconds before the pilot can even prepared to take flight control over the Orbiter and allowing manual operation of virtually any of them would likely be of no use if the sequence somehow got pranged up. ET separation is done at a particular time to assure that the tank will tumble in the atmosphere and break up into a statistically governed maximum size of pieces to minimize fly-down hazards.
All of this information can be found in Chapter 10 of Space Shuttle: The History of the National Space Transportation System The First 100 Missions.
As for joyriding, you certainly can’t get to the Moon (although a conceptual feasibility study was performed on this option), and you’d have a hard time even changing orbit enough to hijack a nearby satellite and still have enough fuel to return to Earth. I suppose you could attempt a landing at some airfield somewhere on your track within the design cross range of the Orbiter, but odds are good that you’ll just end up in the drink.
Stranger
Wow, thanks Stranger.
…continues to amaze…
Yes, it does, and the burn wards are full of squeaky-voiced victims.
This looks like the crowd to ask this, without starting another thread:
What happened to the Service Modules of the Apollo program? Were they just cut loose to burn up in the atmosphere? That’s an awfully large thing to deliberately drop on earth. I bet it wouldn’t even burn completely. Were they pushed off so as to miss earth and just carry on forever?
The shuttle doesn’t acheive escape velocity, so none of its cargo does, either. If it does drop something with a chance of actually reaching the Earth (as opposed to just burning up), they can roughly aim for the middle of the Pacific, where the odds of hitting anything are lottery-comparable.
At least that’s what I’d do.
He is referring to the Apollo program, not the shuttle. Stranger will be the authorative word here (as in many things), but the Service Module did in fact re-enter and burn up. Back in the day NASA was pretty willing to just dump parts and assume it would all work out in the end. I remember someone in the news media asking about the large piece of plutonium attached to the Apollo 13 lunar lander that ended up back on earth. The hope is that it is keeping some fish warm somewhere out of the way. But it could have melted and ended up as a cloud of small particles floating in the (ocean) breeze.
Oops! Confused his request with some of the emergency jettison operations of the Shuttle. Never mind.
With regard to the Apollo 13 Service Module (SM), from the horse’s mouth:The service module, which had been kept attached to the command module to protect the heat shield, was jettisoned on 17 April at 13:15:06 UT and the crew took photographs of the damage. The command module was powered up and lunar module was jettisoned at 16:43:02 UT. Any parts of the lunar module which survived atmospheric re-entry, including the SNAP-27 generator, planned to power the ALSEP apparatus on the lunar surface and containing 3.9 kg of plutonium, fell into the Pacific Ocean northeast of New Zealand. Apollo 13 splashed down in the Pacific Ocean on 17 April 1970 at 18:07:41 UT (1:07:41 p.m. EST) after a mission elapsed time of 142 hrs, 54 mins, 41 secs. The splashdown point was 21 deg 38 min S, 165 deg 22 min W, SE of American Samoa and 6.5 km (4 mi) from the recovery ship USS Iwo Jima.
With other missions the SM was was also directed to re-entry in the South Pacific. The Shuttle ET impacts in the central Indian Ocean. NASA takes reasonable precautions to assure that the fly-down debris pattern avoids shipping lanes and inhabited areas, as well as issuing marine warnings regarding the anticipated impact box, but ultimately they can’t go in and clear out a major section of the ocean. And there’s always some random, tail-end-of-the-Bell-curve chance that some piece will break free, play Skip-To-My-Lou in the atmosphere, and kill some unsuspecting slacker on her lunch break, but the odds are frankly pretty slim.
Plutonium-powered radioisotope thermoelectic generators (RTG) and other nuclear power sources unintentionally re-entering the atmosphere are not an insignificant hazard, and the Canadians once billed the Soviet Union for clean-up costs due to the failed orbit and disintigration of a RORSAT over Northern Canada, but the U.S. also lost a satellite with an RTG (one of the NAVSATs if I recall correctly) and the measured increase in atmospheric plutonium was a fraction of a percent of what the NRC (and now the EPA) considers hazardous. A single atmospheric nuclear test will release several orders of magnitude more material, so it’s not the extinction level event that some protesters of Galileo and Cassini made it out to be.
Stranger
To add to what Stranger said, NASA had a contingency plan in case they ever needed to dump a LM in the ocean, so it wasn’t like they had to do all of this on the fly. In Al Shepard and Deke Slayton’s book Moon Shot, they have an eyewitness account from a ship which just happened to be really close to Shepard’s booster when it smacked down into the ocean. :eek:
Because of the dangers of an RTG smacking down in an inhabited area, the US will no longer use them on anything which is solely designed to orbit the Earth, arguing, correctly, that there’s ample power available via solar cells to run a satellite (or the ISS).
Certain drooling halfwits seem to think that we shouldn’t send anything into space with a RTG onboard, but without them, we’d have no way to power a probe or even keep the electronics from freezing. Were we to not do this, we’d not have the massive amounts of information about the universe we presently have, nor would we be able to get the New Horizons probe out to Pluto. Which would mean we’d have something like another 400 years to wait before we could get any data about Pluto’s “atmosphere” as we don’t have (and probably won’t have) fusion power until Pluto next swings around and thaws out (presently, it’s headed away from the sun and will soon be a frozen hunk/planet/planetoid/dwarf planet/whatever the hell they want to call it these days).
I would imagine one class of stunt that would be quite possible would be to suicidally destroy the shuttle - there must be a hundred different ways that a suitably motivated individual or crew could damage things in such a way as to make things go catastrophically wrong.