My question is in regards to the question of what happened on the Challenger after the explosion. http://www.straightdope.com/columns/950331.html
Why didn’t the shuttle have a parachute like some of the newer shuttles do or the Lunar Modles from the Apollo missions? I am really curious about this. Please help me.
My memory of the shuttle exlosion was that it didn’t exactly come down in one piece, but even if it did, the parachute system you speak of would be incredibly expensive relative to the number of accidents that occur (up until that shuttle flight the casualty rate was…zero)
Such a system could not be a simple “stick it on the outside” type unit or it would burn up in re-entry. So now you are talking about a fancy hydraulic/ electrical system that must be deployed like the landing gear, but otherwise protected in re-entry.
Now keep in mind that when the shuttle explosion occurs, I doubt all the hydraulics/ electrical system were otherwise functioning normally. For that matter, the pilots may have been knocked unconscious by the blast and thus might not deploy such a chute even if they could.
And even if the shuttle did survive quasi-intact and all these systems worked, I don’t know of many parachutes that work well when on fire 
The Shuttle, in case you haven’t actually seen it in person, is huge, so the idea of parachutes was thought to be impractical. If it was necessary to abort after launch, the plan was to separate it from the booster and glide to a landing. The prospect of the booster blowing up was considered to be an unmanageable risk.
I understand all the words, they just don’t make sense together like that.
Even if the shuttle did have a parachute, it would not have mattered since the shuttle was blown to pieces in midair.
Sorry to burst your bubble, microshroom, but the shuttle did NOT burst into pieces in mid-air. As explained by Uncle Cecil, the main cabin survived relatively intact all the way to the splashdown in the ocean. You can read the gory details at: Did the astronauts survive the Challenger explosion long enough to realize their plight?
Actually, I read the Congressional report and they’ve got some fine photos. Challenger’s crew cabin, which “floats” inside the fuselage, was apparently intact following the explosion (which was not an explosion so much as a fireball).
The B-1 bomber was originally designed with an escape capsule similar in size and shape to the Shuttle. After the requisite explosive bolt detonations, the capsule would be propelled away from the fuselage quite a distance before deploying parachutes. Inflatable bags on the underside would help cushion the final shock of landing.
Now, at at US$10000 per lb. to get something into orbit, it would still be expensive, but I think it would be practical. I’ll try to find more info on the capsule, including pix, to substantiate the size/shape similarity claim.
I lead a boring life of relative unimportance. Really.
By this you mean that the whole crew compartment of the B-1, which is similar in size to the crew compartment of the Shuttle, acts as an escape capsule? Interesting. The Shuttle carries up to 7 people though, how large is the crew of the B1?
Anyway, the parachutes on the later Shuttles are for slowing down the Shuttle after touchdown. I don’t think any major safety device was installed after the Challenger incident.
The Apollo and earlier manned rockets, as well as Russian and (now) Chinese rockets, have small rockets which yanks the crew capsule away from the booster in the event of an accident. One cosmonaut was saved when the booster blew up on the pad. If something went wrong with the Shuttle on the pad, the crew has to squeeze out of the hatch.
Anyone know if the Shuttle is the only manned rocket which has the “if an engine quits now we’re dead” period?
The original B-1 prototype (I don’t know if this was incorporated into the production series) had an escape mechanism which blew the cockpit, with all three crew members, out together. One of the prototypes crashed in testing and they lost one guy using this system.
As it happens, I was on the B-1 data team when tail #159 went down. The capsule did indeed seperate and come down by parachute. As I recall, one of the landing bags failed to deploy or deployed improperly, resulting in the death of Rockwell test pilot Doug Benefield. The co-pilot (whose name escapes me, but it was Polish) was seriously injured in the crash but recovered. The escape module was dropped in favour of an ejection seat for each crew member.
I did a very brief search using “space shuttle” and “ejection seats”, but didn’t see anything in the titles that looked worth investigating. (I did see one site that mentioned astronauts Young and Crippen “sat on ejection seats” in Columbia.) Given that accidentally activating an ejection seat while in orbit is undesireable, I don’t think it’s a good idea to put them on a shuttle.
Doesn’t the shuttle have an escape tunnel?
“I must leave this planet, if only for an hour.” – Antoine de St. Exupéry
Are you a turtle?
On a similar theme, the F111’s crew capsule detached, and the capsule returned to earth as one unit. However it is only maybe 40 feet long, and 10 feet wide. It was only designed to hold two crew members. Goes to show that the method of recovery of a crew capsule is good enough for the Air Force
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I would cite the successful test of the X-38 Crew Return Vehicle as evidence that the Orbiter is a bastardized, Congressionally crippled space vehicle which stands as a testament to the versatility of mankind–on a budget.
The X-38 relies, whether acknowledged or not, on the research done by the Lifting Body project of the late 60’s-early70’s. You know, the one Steve Austin crashed at the beginning of every Six Million Dollar Man episode. The Lifting Body project was in turn a foster child of the Air Force’s Dyna-Soar project. It also incorporates parafoil technology that was originally considered for the Gemini and Apollo missions for land-based vehicle returns.
William Proxmire, God rest his soul in a giant vat of rancid butter, was active in repeatedly holding his “Golden Fleece” award over NASA’s head while the development of the Orbiter was completed. Among the innovative devices that were intitially to be included in the design of the Orbiter were ejection seats and emergency fly-around rockets for the Orbiter. Both were canned because of prohibitive costs. Later re-designs made the crew compartment of the Orbiter detatchable so that a parasail apparatus could be deployed in the event of catastrophic failure. That, too was rejected for monetary considerations.
However, that particular redesign was the one that was eventually approved. When the Challenger disintegrated, the capsule section, sans the terribly expensive parafoil crew return system, tumbled into the ocean, and inconclusive evidence points to the possibility that at least one of the creew members was able to open an emergency locker during the nine-mile descent.
The Orbiter still does not have the ability to circle around the runway should it miss its one opportunity to hit good ground in Florida. Cost considerations and the decrepitude of the two modified 747’s built to transport the Orbiter impel NASA to strongly encourage their pilots to land at The Cape, rather than Edwards, White Sands, or other possibly safer spots, in spite of astronauts’ protests. If and when an Orbiter makes a great swath through the swampy grounds of Canaveral, I hope someone holds a wedge of Wisconsin Cheddar to the sky and says, “this, William, is what you have wrought.”
I can’t find anything on the Web with dimensions or pix of the B-1 capsule, although the F-111 capsule seems rather popular. B-1 has a crew of 4, which makes the capsule similar in length and width. The Orbiter’s two levels make the crew compartment taller, but weight is really the major issue: the orbiter crew compartment has lots of stuff in it. As mentioned, the B-1 capsule was dependent on landing bags to cushion an otherwise fatally hard parachute descent, so a similar system for the heavier Orbiter might be difficult. In fact, a decision not to upgrade the F-111 was once made because it would make the escape capsule too heavy.
I vaguely remember the parasail Sofa King mentioned, but had no idea the floating Shuttle crew compartment was part of an escape system originally. Excellent info there!
Despite the loss of life in the B-1 capsule landing, the reason given for the switch to ejection seats was the logistical nightmare of checking all the connections and severance points between the airframe and the capsule. With the switch from supersonic B-1A to subsonic B-1B, the need for an encapsulated escape system (first used for the B-58, I think) evaporated.
Yes, Columbia (and Enterprise, IIRC) had ejection seats while being flown by two-man crews during testing. The whole fleet now has an egress system (for use during controlled level flight only!) that basically consists of jumping out.
Here’s a neat bit:
High-speed, high-alpha deadstick landings on water or unprepared terrain are not conducive to health and long life, so we suggest you take a flying leap.
Well, I meant to say the gas tank exploded. My keyboard is messed up. What are you gonna do?
And it all happened because of sucky o-rings.
Two wrongs do not make a right…but three lefts do.
The XB-70 had escape capsules for the two
man crew as well.
… which the engineers at the company that built the module containing those O-rings figured out probably wouldn’t survive a low-temperature liftoff (it was 28 degrees when the liftoff occured) - but they couldn’t convince NASA or their upper management to call off the launch.
A few years ago I went to a seminar on making management presentations. The rest of the seminar was godawfully boring, but they had a fascinating section detailing those engineers’ frantic attempts to alert NASA and their management to this problem.
The engineers had discovered that previous shuttle launches that occured below 50 degrees all had O-ring damage, with the damage more significant as the temperature dropped. And, as all materials engineers know (the seminar leaders told us), material flexibility drops off with the square of temperature drop, not just linearly. The shuttle didn’t have a chance at 28 degrees.
The engineers were given an opportunity to make a last-minute presentation of their data describing the problem to NASA and their upper management. The seminar leaders showed us the almost-completely-unintelligible charts and graphs that the engineers presented. Given the incredible political pressure NASA was under to launch the first teacher into space, those charts didn’t stand a chance - and NASA ordered the launch.
The seminar leaders then put up alongside those original charts some simple charts that detailed the problem in such a clear manner that NASA almost certainly would have called off the launch.
So (the seminar leaders told us), the shuttle disaster was really caused by poor presentation skills.
“Poor presentation skills”, my o-ring! Were I the head honcho at NASA, and my engineers told me, “If you launch now, it’ll blow up”, I would either cancel/postpone the launch just on their say so, or at leasttake the time to make sure that I understood their arguments. Of course they weren’t as clear as they could have been, they were kinda rushed, and had the stress of knowing that seven lives and umpteen dollars depended on them. I don’t blame the engineers, I blame the management.
“There are only two things that are infinite: The Universe, and human stupidity-- and I’m not sure about the Universe”
–A. Einstein
Regarding water ditching: would only the impact be the fatal factor? Since the shuttle is presumably watertight, couldn’t the crew survive long enough for rescue if the Shuttle sank in relatively shallow water?
DHR
From a recent ep. of Futurama, as the ship sinks in the ocean:
Crew member: “How many atmospheres can the ship take?”
Prof. Farnsworth: “Since it’s a space ship, I’d say between zero and one.”
Actually, the windows, hatches, etc. need to keep the wind out during liftoff just as much as they need to keep air in while in space. So, an intact cabin should be able to keep the crew going for a while.
NASA just doesn’t seem to think ditching on water is survivable at all, since the shuttle’s as much lifting body as it is plane. As soon as the tail hit, the nose would slam down onto the water. Pretty nasty with that high stall speed.
I can’t site any references, but from what I remember:
In the first four flights the shuttles were equipped with ejection seats (two of them for a two-man crew). The pilot and copilot both wore full pressure suits during takeoff and landing, just like Mercury & Apollo (a high altitude ejection would require it).
After flight number four the shuttle’s status was changed from “test” to “operational”. The ejection seats were removed and the crew cabin was now deemed a “shirt-sleeve” environment. Regardless, a shuttle could never have had more than two ejection seats, and to carry its full payload (i.e. be “operational”) it couldn’t have any.
After Challenger, the crew went back to wearing full pressure suits at TO & L (a practice which should never have been stopped to begin with).
Although its debatable, since the G forces of the explosion & breakup were not enough to even cause unconciousness let alone death, and since the crew cabin remained relatively intact, if they could have unbelted and bailed out of the falling crew cabin (they would have been weightless once reaching terminal velocity) a supply of oxygen and a parachute would have saved them.
I for one welcome our new insect overlords… - K. Brockman