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57

Yes, it really happened. It took place at the Lockheed Martin Space Systems factory in Sunnyvale, California. As the team was turning the satellite into a horizontal position, they found out that the twenty-four bolts that were supposed to hold it in place had been removed by a technician - and the action was never documented. According to NASA: The ...


49

Key data for the Columbia accident investigation was provided by recovery of the MADS (Modular Auxiliary Data System) recorder which amazingly survived reentry and was found largely intact. The MADS recorder captured crucial engineering data that wasn't sent to the ground through telemetry. As the first spaceworthy orbiter, Columbia was instrumented with ...


45

Not even close. In fact, at 12 seconds in, you're looking at maximum damage to not just the pad itself, but the surrounding area as well. You're going to have tons of debris (most of it burning and possibly carrying even more unburnt fuel) fall from 1500-2000ft range in a giant umbrella of destruction. In 1997, a Delta II carrying the GPS IIR-1 satellite ...


45

This is indeed part of the procedure that is invoked when a contingency has occurred. It is part of Standard Operation Procedure 2.8 - JSC Contingency Plan, which can be found in the Shuttle Flight Control Operations Handbook (link to 538-page pdf - referenced here) on page 2.8-1. It provides the steps to be taken to secure all data for future investigations ...


40

The static test wants to be done relatively close to launch day, to minimize the likelihood of anything happening to the engines between the test and the launch. The more conservative procedure is to attach the payload after the static test, but they'd have to lower the rocket, move it back indoors, stack the payload, take it back out and reelevate it. ...


39

The answers to all your questions are described at length in section 6.4 (page 173) "Possibility of Rescue or Repair" of the CAIB Report. Appendix D-13 "STS-107 In-flight Options Assessment" is a very detailed description of the process that was utilized to come up with the self-repair and rescue options. Major elements of the process: Assumptions were ...


34

Providing crew escape for all phases of flight of the Space Shuttle, given its design architecture, was simply not practical. Keep in mind you have up to 7 crew members on two decks. Keep in mind that the flight regime consists of large ranges of altitude and velocities. Keep in mind that it would have to cover launch, landing, and several abort modes. ...


32

NASA tends not to insure its missions, nor do any government missions. These missions are one-of-a-kind, and so expensive that the satellite insurance market would have a hard time making it work. They simply triple-check everything they can, and expect to lose a few missions, so called "Self-insurance". They have considered insuring things like the ISS ...


31

Yes, the launch escape system was used, contrary to earlier reports based on assumptions and ignorance of Soyuz hardware. However, it was not the tower that we are familiar with on Mercury and Apollo era manned rockets that was used. The Russian launch escape system, SAS (Система Аварийного Спасения, or Sistema Avariynogo Spaseniya, meaning emergency ...


31

This is one case where Wikipedia says it all: Apollo 1's (AS-204) Saturn IB rocket was taken down from Launch Complex 34, later reassembled at Launch complex 37B and used to launch Apollo 5, an unmanned Earth orbital test flight of the first lunar module, LM-1, in January 1968 [65]. The Wikipedia article cites the following primary reference: "Apollo ...


30

While there is onboard recording, the significant difference between launches of space craft and those of aircraft is the extensive realtime telemetry used in rocket launches. Every piece of data that can be sent live to the ground station is sent. This is essential in an endeavour which is still incredibly dangerous and with high odds of destruction or at ...


29

This mainly depends on the cause of the scrub, it seems. I went back through Ariane 5 launches. When a scrub was caused by a technical problem, it'd take several days or weeks to make another attempt. The vehicle has to be drained of fuel, rolled back to the assembly building, failure analysis etc. When the cause is external (weather, nimrods driving their ...


27

I did a crude spreadsheet sim using the Rogers Commission report to get throttle times, to wit: Throttle down to 94% at 24 seconds Throttle down to 65% at 42 seconds Throttle up to 104% at 65 seconds I neglected startup propellant consumption and assumed step function throttling. I took liftoff O2 load to be 1,387,457 lb and H2 load to be 234,265 lb. I ...


27

The only casualties in space (above the Kármán line) are the crew of Soyuz 11 who were still in orbit when they died but about to reenter the atmosphere. All other casualties like Komarov in Soyuz 1 or the Columbia Space Shuttle disaster were during reentry well below the Kármán line. The Soyuz 11 was about to land so you may count that as "during return ...


26

Rocket guidance systems generally use a fixed inertial platform based on gyroscopes to determine their orientation in space; an accelerometer solution would be useless to determine orientation (though helpful for position determination) as soon as the rocket was in motion. https://en.wikipedia.org/wiki/Inertial_platform Once operating, the platform's ...


25

Yes, there is a procedural change, at least with NASA launches. In NASA, launches are controlled by the Launch Control Center (LCC) until the rocket clears the tower, and then are handed over to the Mission Control Center (MCC). I'm not sure how other organizations do it.


25

14G sounds like a lot. To put it in context: the acceleration you can endure depends on the force vector. The position in which we can withstand G-forces best is forward (using the directions from the XKCD diagram), so spacecraft seats are placed to take advantage of this. When the rocket sits on the pad, the astronauts lie on their back. fighter pilots ...


25

It stands for Signal Conditioning Equipment. From Wikipedia The loss of all three fuel cells put the CSM entirely on batteries, which were unable to maintain normal 75-ampere launch loads on the 28-volt DC bus. One of the AC inverters dropped offline. These power supply problems lit nearly every warning light on the control panel and caused much ...


24

Update 7/20/2015 via Elon Musk's Conference Call, compiled by /r/spacex and twitter sources Preliminary conclusion is that a COPV (helium container) strut in the CRS-7 second stage failed at 3.2Gs. We analysed a lot of data, took 0.893 seconds before first sign of trouble and end of data. Preliminary failure arose from a strut in the second stage ...


24

The breakup of Challenger occurred about 73 seconds into flight. Main engine cutoff normally occurs about 510 seconds into flight, implying that about 86% of the fuel would be remaining. (Many sources give 480 seconds, but I suspect that's a simple division of the tankage mass by the full-throttle consumption rate; looking at actual mission reports supports ...


23

Does he mean lock the doors in the NASA building, in order to begin some internal investigation, and nobody is allowed to leave, as a matter of policy? Yes, this. It's part of a standard procedure to ensure evidence is preserved for the investigation. It's to prevent people entering as well as leaving.


22

I want to focus on aerodynamic stress however, like when a rocket deviates from its path or has a wrong angle of attack, what causes it to be destroyed? In many cases, it's not aerodynamic stress. Many launch vehicle explosions result because they are commanded to do so. Every launch vehicle launched from the U.S., including the solid rocket boosters on ...


21

In some Mercury flights, the astronaut had a personal parachute with them. The Gemini program used ejection seats, which could be used during launch and reentry. Later on, they realized that igniting a rocket-propelled ejection seat wasn't a good idea in a pure-oxygen atmosphere. The Vostok capsule also had an ejection seat, but not as a backup: the ...


21

The Space Shuttle Orbiter had a flight mode whereby, at or below ~50,000 feet of altitude during the reentry (or, in the event of an ascent abort, the gliding, unpowered phase of flight), the commander could command an autopiloted, wings level glide at about 190 knots equivalent airspeed (KEAS). The plan was then, while the Orbiter was gliding, that the ...


21

It's eight or ten seconds from the sudden flare at the base of the rocket 'til it hits the ground and actually explodes. I'm not an expert, but I don't see any particular reason why power to the guidance systems would have been off-nominal immediately after the initial flare, and if the controller were watching the power readouts instead of the visual, he ...


20

[Background: I'm writing this as a developer whose firmware's in flight on several substantial satellite missions. I've developed attitude control systems, working directly with RW hardware engineers.] As Hash says, there is a lubrication distribution issue with conventional mechanical-bearing reaction wheels. The result is increased wear, leading to wear ...


20

A typical approach as used on Mars rovers is to keep the previous build on the spacecraft as the default to boot to on a reset. You load the new build and command a boot to the new one. Then you test it. If something goes south, it will reboot to the old build. Or you can command a reboot to the old one. Once you're confident in the new build, you make ...


20

Several issues have been reported informally, mostly in Elon Musk tweets. Not as many cameras turned on as usual Storage on site was damaged, and not all data was uploaded during test This fueling event, for a static fire, was a really routine thing by this point. They thought they had fueling down pat. The last fueling accident like this in the US was ...


17

Don't ever take what's portrayed in a scifi movie as fact. You can use the fingers on one hand to count the number of scifi movies that go out of their way to be faithful to science. "Mission to Mars was not one of them. (Nor was Total Recall.) Will you die if you take your helmet off in space? Of course. Your brain needs oxygen, as does the rest of your ...


17

The story behind this is one of several layers of procedures, as is documented in a review of NASA "mishaps". Essentially, the story comes down to the following sequence of events: A team prepared the vibration testing, including putting the bolts on. A second team removed the bolts, to use for another purpose. This removal was not documented at the time. ...


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