Questions tagged [launch-escape-system]
A Launch Escape System (LES) is a system connected to the crew module of a manned spacecraft. It is used to quickly separate the crew module from the rest of the launch vehicle in case of emergency (such as an explosion of the rocket).
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Why didn't the Space Shuttle have a launch escape system?
Since the very beginning of space exploration, rockets had some sort of Launch Escape System (LES). From this Wikipedia article, we know that Mercury and Apollo had an escape tower, while Vostok and ...
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Why did SpaceX choose to use Hydrazine over newer "green" propellants for Dragon 2?
Firstly, I understand the need to use hypergolics over cryogenics as part of Dragon 2's abort and landing sequence - they provide "instant on" thrust and are throttlable with very wide ...
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How hard is it on the crew to go through the 14+ g's of a launchpad abort of the Soyuz, or the Falcon system?
It's only for 5 seconds, but that is an awful lot of force. The Falcon system is similar and presumably also involves very high-g forces. Could injury result from the abort itself in either case?
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Why don't unmanned launch vehicles include launch escape system for payload?
Mention of Launch Escape System (LES) brings to mind images of the crew on board a spacecraft ejecting at launch; the crew being the most valuable cargo on board.
Launch vehicles may also be unmanned,...
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Challenger Shuttle: could the crew have survived?
Some sources point out that the shuttle cabin stayed intact following the solid rocket booster explosion, and that in fact, it is likely the crew died upon the cabin impact into the ocean.
The space ...
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How did the attitude system of the uncrewed Soyuz 7K-OK No.1 fail on the launch pad in 1966, killing ground staff as LES was activated?
Wikipedia has a stub article on the loss of the Soyuz 7K-OK No.1 test flight in 1966-12-14, but this part doesn't make sense to me:
However, once the Soyuz rocket's engines ignited, they did not ...
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Was the LES used in the MS-10 abort?
I can find no clear information regarding the use of the launch escape system in today's Soyoz MS-10 abort-to-ground. The failure seems to occur just as LES jettison is scheduled to take place.
The ...
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Could the Apollo lunar ascent stage have separated from the descent stage before touchdown in an emergency?
In case the Apollo Lunar module had approached the landing site at way too high velocity, could the ascent stage have separated and returned to the command module before a crash? Thus performing a ...
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Has a pad abort ever been done on an actual launch?
In light of the recent SpaceX Dragon test, I was wondering if any pad aborts have ever been performed during an actual launch? To my limited knowledge, none have occurred, despite the Soyuz and Apollo ...
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Why was Dragon sent to the isolation room?
I'm asking about this photograph that was published on SpaceX Flickr photostream, which I also noticed in a few recent articles (e.g. this one) about the upcoming Crew Dragon pad abort test:
SpaceX ...
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Why is the descent module of the Soyuz in the middle of its stack?
The Soyuz is made up of three major components/modules.
The Orbital module on top, basically a sphere, which is basically extra room, and contains the toilet, which allows for some modicum of ...
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Why are launch escape towers jettisoned early?
Why are launch escape towers usually jettisoned fairly early in the flight? What if a problem went wrong during an upper stage burn and the escape tower had already been jettisoned? I know that ...
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Why didn't Saturn V have grid fins? Long March and Soyuz do!
From the question What are these four “waffle-like” structures on top of the Long March 2F just launched? and @RussellBorogove's answer there we can see that the Long March 2F carrying the Shenzhou-11 ...
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Are there any Pusher Launch Escape Systems in actual use?
Previous manned spaceflight vehicles, that had a Launch Escape System (Excluding you space shuttle!) usually seemed to favor the notion of a tractor (Puller) style LES.
That is, the manned module ...
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Does a fully loaded Starship really have a thrust to weight ratio less than 1 at sea level?
If Superheavy fails during launch (or even fails to launch in an unsafe way) the Starship itself might well be able to just light its engines and fly a suitable suborbital trajectory
https://space....
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Why were ejection seats used in Project Gemini instead of a tower escape system?
In Project Gemini, the Titan II GLV space rocket used as fuel hydrazine and nitrogen tetroxide, so safety concerns over its toxic propellants were present. But along with the special care that was ...
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What kind of launch escape system (LES) does Dream Chaser have?
What kind of launch escape system will be aboard Dream Chaser?
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Does Soyuz LES take the service module?
During Jettisonable Emergency Escape Head Section abort mode, the head section of the rocket is separated and pulled away by OGB SAS (the escape tower) to safety away from the malfunctioning lower ...
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How safe are launch escape systems?
Are there any published numbers for any crew vehicle for the probability of LOC (loss of crew) given the launch escape system has been activated? I am interested in both design goal numbers and ...
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Escape system of SLS vs Ares I
One of the criticism directed at the Ares I rocket was the danger during a launch termination of the solid-propellant 1st stage. As far as I understood it, a terminated Titan IV solid-propellant ...
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Why doesn't the BFR/Starship have a launch escape system?
This question let me wonder whether SpaceX' Starship has a launch escape system. It really seems to have none. The obvious question is why not, it sounds pretty negligent to me not to have some kind ...
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When have astronauts been launched without launch escape system (tower)?
The Vostok spacecraft used by Yuri Gagarin seems to have had an "ejection seat". The Soyuz launcher has an escape tower, which at least once saved its crew. The space shuttle of course did not have ...
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Were ejection seats on the Space Shuttle a practical safety system?
The first four STS missions were flown by Columbia with two pilots and had ejection seats as an option. These seats were eventually disabled (by STS 5) and removed (by STS-61-C). They could only be ...
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Can a crewed capsule land safely if its launch escape tower does not separate?
Apollo, Soyuz and Orion have used, are using or will use launch escape towers. If it is not needed, it must separate during flight. What if it does not separate? I suppose that the spacecraft would ...
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What exactly does it mean to human-rate a rocket? As opposed to the escape system?
The escape system is that thin pointy part at the very top of the rocket. It has powerful solid rockets that basically act as an "ejection seat" for the entire crew capsule.
So when we talk about "...
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Did Boeing's Starliner do an inflight abort test?
Did the Starliner perform an inflight abort test? I could not find any videos to support the same. Isn't a pad abort and an in flight abort neccesary before sending humans to space? Can the starliner'...
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Does a launch escape system have any lateral propulsion?
Many manned spacecraft have had an "escape tower" to propel the crew capsule safely beyond the booster, if an abort is needed. What prevents the booster from simply continuing into the path of the ...
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Escape tower details of Mercury spacecraft
In the details about the escape tower for the Mercury capsule, I noticed that it had three nozzles, all connected to a single combustion chamber of the solid propellant.
How did the designers ensure ...
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Why did early MOL/Gemini aborts involving the separation of the crew capsule from the launcher still call for the crew to eject afterwards?
The Gemini spacecraft, often given as an example of a manned space capsule with no launch escape system, or LES (it used individual ejection seats instead), did, in fact, have an LES, although not one ...
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Why were the canards on the Apollo LES retained even after being proven unnecessary?
In the event of a Mode IB abort during an Apollo launch (an abort initiated between 3 and 30.5 km altitude), a pair of canards would be deployed from the tip of the spacecraft's LES in order to force ...
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Why is ISRO Launch Escape System so SLOW?
I've just watched a video of the recent test and one thing I noticed is that comparing to other LES, like Mercury, Dragon, Soyuz, it looks really sluggy - like it has like 1.3-1.5 TWR. For pad abort, ...
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Will the EFT-1 mission for Orion carry an escape tower?
December 2014 is the scheduled date for the Exploration Flight Test-1 (EFT-1) mission of the Orion space capsule. It will be launched on a Delta IV Heavy rocket as a surrogate for the unavailable SLS ...
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Why not turn off the main engines while using the launch escape system on liquid fuelled engines?
I've seen a couple of launch escape systems firing and the rockets main engines are on, isn't it more safe if you turn off the engines? Edit: i agree that the engines turning off might be not so ...
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Launch escape trajectory
Say a fault triggers the launch escape system and the crew vehicle fires away.
What trajectory would the LES controller follow?
Keep minimal angle of attack to minimize aerodynamic loads (e.g., in ...
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When lower stages explode, can upper stages just fire and escape?
If Superheavy fails during launch (or even fails to launch in an unsafe way) the Starship itself might well be able to just light its engines and fly a suitable suborbital trajectory to a safe landing ...
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Why was the LES on Apollo white?
In below images they’re red for Mercury (both on the Redstone and Atlas boosters). But the Apollo ones are white. Why were the Launch Escape Systems of Apollo white?
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Riding out an exploding rocket
It is known that at least some of Challenger's crew survived the explosion, while conscious. If the cabin had a parachute, they may have lived. This is despite the Space Shuttle stack being one of the ...
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Dragon launch escape: is nose cone ejected for parachute deployment?
Dragon’s landing parachute is stowed roughly in the nose cone hinge area, and this leads me to believe the nose cone has to open for the chute to deploy.
In normal operations, I believe the nose cone ...
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Dragon Launch Escape: Attitude Control?
I've read the superdracos have a deep throttle range suited for attitude control during powered landings---an old requirement that's long been dropped.
This has me wondering: are the superdracos ...
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Dragon launch escape: roll control?
Dragon’s four superdraco pods are positioned well for pitch and yaw control, but not for roll control.
So I’m wondering how they’ll control for roll during launch escape—or if they’ll even control for ...
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Could Apollo have used the launch escape system as a booster?
Getting to space requires ruthlessly eliminating weight from launch vehicles. Older spacecraft like Apollo carried big Launch Escape towers. For an Apollo mission flying on a Saturn V, the LES meant ...
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Is a low-altitude, stable glide really absolutely needed to bail out of the space shuttle?
After the Challenger disaster, the Space Shuttle astronauts were outfitted with pilot spacesuits equipped with parachutes and internal emergency oxygen supplies, and the space shuttle was equipped ...
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What if satellites could be recovered during a launch failure? [duplicate]
How heavy would a capsule have to be to return a satellite safely to earth in the event of a launch failure? Would a satellite survive the loads endured by astronauts during an abort? If not, is there ...
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Launch excapse system for satellite payloads? [duplicate]
Once a rocket lifts off, there is usually no abort mode that does not involve the destruction of the rocket, and on a satellite launch, the payload.
Therefore, expendeble satellite launchers are quite ...
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How would a landing escape system be designed? [duplicate]
Launch escape systems have been used for half a century and have worked great when tried. But entering Earth's atmosphere from orbit and landing is at least as dangerous to astronauts, and have cause ...
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How was the Stabilo crewed re-entry vehicle supposed to work? A tractor engine with four nozzles?
ARCA Space's webpage for the Stabilo program has a description and an image. Hydrogen peroxide monopropellant? Reaction closer to the crew than the nozzle?
With thrust at the top, it seems that ...
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Why doesn't the crew dragon spacecraft of Polaris dawn mission appear to have a launch escape system?
All the crew Dragon spacecraft of SpaceX have a launch escape system powered by super Draco engines in case of an anomaly.
But the on the spacecraft of the Polaris dawn mission, the Dracos appear to ...
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