If by "land" you mean "make a runway landing", sure. But I'm not sure how valuable that is with current technology and the current state of space travel.
For starters it saves you a trip in an aircraft carrier or a fleet of helicopters flying into some 500km wide steppe...
Part of the problem is that the shuttle is much bigger than is needed. We have far less need for downlift capacity than uplift, and you get far better payload capacity sticking an uplifted payload on the same launcher as a capsule rather than putting it in a payload bay on a spaceplane (if it needs manned attention), or sticking it on a launcher all by itself (if it doesn't).
So you're entirely denying the usefulness of payload return from orbit? Not all payloads can be thrown away to burn up in the Earth's atmosphere, some research payloads (such as LDEF, a classic example of shuttle capabilities) are a good example of that.
In addition a spaceplane allows you to have a "work platform" in space, it's kinda advantageous when you get to keep all those tools and equipment for future missions rather than burning it all up.
STS over the past two and a half decades has a safety record similar to Soyuz in the past four. And Soyuz hasn't had a fatality for almost the entirety of those four decades that it's been around.
But in that time, the two have flown a similar amount of missions. It's number of flights that counts, not time.
I can also say that at least one shuttle accident was not caused by the vehicle at all, but rather
bad management. The other is more of a critical design flaw within itself, yes. But for what it is technologically- and for all the huge! gigantic! dangers! intrinsic to it's design, it has pretty remarkable safety.
If your country has not yet started a spaceplane program, there is nothing lucky or smart about starting one and ending up like Buran. If you *have* started a spaceplane program, then it is lucky/smart to have it end up like Buran and have the program go nowhere after a slight waste of resources and time, rather than have it end up like STS and have it set your space program back thirty years with an attendant large waste of money and time.
I would definitely not call STS a program that "set the space program back 30 years". Many things were learnt during the shuttle program, and it's explored new boundaries to an
extent- albeit technological and historical ones, rather than spatial ones.
In short, even though more money was spent (and wasted) on STS, it provided far more advances than Buran ever did in it's "cost saving cancellation".
Buran failed to succeed well enough to push Soyuz out of the way. STS pushed the prospect of any more capable launcher out of the way, and here we are thirty years later at the end of the shuttle program with no certain successor.
The Russians were lucky/smart to cancel Buran and retain Soyuz, which is a much better idea than Buran. We were unlucky/dumb to have the Shuttle drown out the potential for a mass-producible successor to Apollo/Saturn. 30 years later, we *still* don't have one.
Honestly, I don't think they had a choice about Buran, considering their economic situation. And STS was supposed to be the regular successor to Apollo/Saturn and
more, it just didn't turn out to be. At least not enough, anyway- there were still improvements in launch infrastructure cost over the Saturns, for example, but not nearly enough to present the system as the cost effective regular, revolutionary one it was advertised as.
The difference is in the fact that an effective first stage for an orbital vehicle ends up traveling much faster than the mothership in an air-drop test. Also, recall that most of these vehicles were test vehicles, rather than part of some sort of infrastructure meant to do anything other than validate concepts. (And those that were meant to progress any further than test vehicles while remaining air-dropped, such as the XF-85 generally failed miserably).
XF-85 didn't fail because it was air dropped, it failed because it was, all round, a pretty crappy idea.
These test aircraft are dropped from bombers. A dedicated system would use dedicated vehicles. I don't see why it's impossible or
bad in any way, it makes less sense than an SSTO because of the increase in system and launch complexity, but it's nowhere near as silly as the XF-85, for example.
I don't know, but regardless of likelyhood, a birdstrike on launch is more dangerous because the risk of compromise to the TPS it presents is *before* the hot part of reentry, whereas a birdstrike on descent would be overwhelmingly likely to occur after reentry, at some point below 30,000 feet, where damage to the TPS would not present any LOCV risk.
Of course, but that's not my point. My point is that birdstrike liklihood is far higher on approach and landing than it is on launch (you don't have birds getting scared away from the launch site). The low speed impact seemed like a relatively isolated incident, and happened early enough in the launch that it did not cause damage. By the time the stack is fast enough for such a strike to cause considerable damage, birds would have been scared well away by the launch. I'm no avian behaviour expert when it comes to rocket launches, but if I were a bird, I'd probably get the heck out of there as fast as possible.
Bird strikes damaging the TPS is probably the last thing you'd want to worry about, MMOD threat is far more problematic.
They are designed for such accelerations because they *can* be designed for such accelerations without making them obscenely heavy. A winged design is simply harder to stress for g's, and will experience higher g's at high AOAs. Wings are likely to break before the fuselage of an atmospheric vehicle, and if the fuselage does break, are likely to provide the forces that break it.
Exactly. Nothing intrinsic to wings, any structure of the size and vague shape as the orbiter (such as a wingless cargo pod) would be just as hard to protect against obscene accelerations.
(Also, Soyuz 18a ended up 5 g's over the design limit and both vehicle and crew survived).
That's nice, but not special. I can make several things survive 5 Gs over their design limit, including rocks and metal ingots...
Also note that the crew cabin of Challenger stayed fairly intact until impact, and crew members are thought to have survived the immediate breakup, only to be rendered unconscious by lack of air and then killed by the final impact. A capsule of similar size, equipped with parachutes, mounted on top of the stack, and equipped with an LES would quite possibly have brought its crew back alive.
Yes. Or, a breakaway capsule, with a crew protected by escape suits, could also have potentially brought the crew back alive.
I'm talking about capsule breakup in a different scenario entirely (for example, regarding launchers that actually launch capsules, instead of shuttle stacks). I believe a simulation for Orion, at least, showed a particular second stage failure as sending high velocity fragments through and past the capsule before the LES had time to fire.
Furthermore, the breakup of the orbiter itself in the Challenger breakup was a result of aerodynamic forces: Both SRB's, including the one that was the cause of the whole disaster, continued in powered flight for 37 seconds until destroyed by range safety, despite also sitting next to the tank when it fell apart and being showered in debris (and being already compromised *and* having hit the tank, in the case of the right SRB). A capsule at the top of the stack, especially if equipped with an LES to carry it clear, would have been upwind of the breakup and would likely have encountered much less in the way of both aerodynamic forces and debris, as well as likely being able to handle more of both.
The crew cabin was on the side of the tank, was attached to a disentegrating vehicle, and caught in that airflow, and wasn't specially designed to survive an accident like that. Yet it survived the actual disentegration intact, the astronauts onboard were just badly protected from the conditions at altitude. And a high velocity water impact.
But there's an even better precaution, that can be used to eliminate a Challenger-like failure entirely: Have proper management, proper safety precautions, and don't make skimp or make compromises on safety,
anywhere. Challenger happened not because STS was a bad vehicle, but because of bad management.
Not just that, but many types of launch abort with a HTOL spacecraft might simply involve shutting off the engines and beginning a descent towards a suitably located airfield. A birdstrike could be dealt with in a similar manner to any aircraft birdstrike.
Well yes, in that case you could return to (a) base if you wish.
HTOL is by
far safer when compared to HTVL.
It could, but a capsule/LES design is much more resilient against failures of the rest of the launch stack than a winged design, especially a winged design bolted to the side of the stack shuttle-style.
The wings don't matter. The wings are gone at that point, you're leaving them behind...
The idea is to have some sort of breakaway pod from the spaceplane itself, saving the entire vehicle would be far too clumsy.
