6 ms·

They had pogo oscillations that could cause the engine to shut down. There were abort procedures for thrust failures.

WalterBright 8y ago
I doubt anyone wanted to try out the abort procedures with their own bodies atop a tank of burning rocket fuel shaking itself to pieces :-)
- pdonis 8y ago
  It doesn't seem like anyone was enthusiastic about trying them even for practice. According to the Wikipedia page on space shuttle abort modes (linked to from the apollo abort modes page), NASA considered making the first flight of Columbia a practice RTLS abort; but the mission commander, John Young, declined, saying "let's not practice Russian roulette".
  - WalterBright 8y ago
    Right, if you're taking a big risk of death, have it be for the payoff of a useful mission. Not a practice flight where the payoff is simply that you didn't die.
Maakuth 8y ago
Here's a Wikipedia article about the abort modes. It probably would get pretty tense if you had to abort when the rocket started going through 'rapid unplanned disassembly', though. https://en.wikipedia.org/wiki/Apollo_abort_modes https://en.wikipedia.org/wiki/Apollo_abort_modes
- lloeki 8y ago
  > rapid unplanned disassembly Is that proper aerospace lingo, like "controlled flight into terrain"? https://en.wikipedia.org/wiki/Controlled_flight_into_terrain https://en.wikipedia.org/wiki/Controlled_flight_into_terrain
  - SomeHacker44 8y ago
    As a pilot, CFiT is very descriptive. RUD sounds to my (layman’s) ear to be a nice way of saying “uncontrolled unplanned self destruction.” I could call an incident where a plane engine (on my plane) threatened to tear itself and the wing to bits because combustion became unbalanced, causing a vibration that had I not shut it down would have led to a rapid unplanned disassembly too, and likely not ended as well as the preventative.
  - TeMPOraL 8y ago
    Yes. It roughly translates to "exploded, though we didn't want that". There's an equivalent term fof CFiT too - lithobraking. It's like aerobraking (using planet's atmosphere to shed some speed), except with rocks.
- tragomaskhalos 8y ago
  Similar protocols for the Shuttle of course; was in Gambia in 1990 and got chatting with some NASA folks just sitting round the pool at a nearby hotel - they told us they were there as there was a specific abort phase whereby the Shuttle would glide across the Atlantic and land at Banjul airport (whose runway NASA had paid to have extended for this purpose!); in that unlikely eventuality they would have to leap into action, otherwise it was a nice few days in the sun for them.
  - QuotedForTruth 8y ago
    There were a lot of these runways across the Atlantic. I wonder how many at a time they staffed with people like the people you met. https://en.wikipedia.org/wiki/List_of_Space_Shuttle_landing_sites#Transoceanic_Abort_Landing_Sites https://en.wikipedia.org/wiki/List_of_Space_Shuttle_landing_...
    - tragomaskhalos 8y ago
      After posting I checked the dates from memory vs shuttle launch dates from Wikipedia, and this would have been some weeks before the launch ; so I wonder if in fact their job was to drop into the various emergency landing areas and just do a check that everything was lined up just in case; otherwise it'd be very costly to have teams in situ at all of them.
      - QuotedForTruth 8y ago
        The shuttle was a very expensive program! Each launch was something like $450 million. I wouldnt be surprised if they had small teams at 2 or 3 runways as contingency plans. If the shuttle landed some where they would definitely need help getting out of it and I doubt it would be much cheaper to keep locals trained and ready.
  - Maakuth 8y ago
    Sadly the shuttle abort protocols were not effective for Challenger-like, catastrophic failure modes. My, admittedly layman's, understanding is that Apollo abort system would have been able to evacuate the crew in a number of pretty dire scenarios.
- russdill 8y ago
  Yes, I wrote a bit too quickly there. Pogo might, but doesn't generally shut down engines, it shakes the launch vehicle apart. Engines with out of control pogo oscillations could be commanded to shut down to avoid a boom.

I doubt anyone wanted to try out the abort procedures with their own bodies atop a tank of burning rocket fuel shaking itself to pieces :-)

pdonis 8y ago
It doesn't seem like anyone was enthusiastic about trying them even for practice. According to the Wikipedia page on space shuttle abort modes (linked to from the apollo abort modes page), NASA considered making the first flight of Columbia a practice RTLS abort; but the mission commander, John Young, declined, saying "let's not practice Russian roulette".
- WalterBright 8y ago
  Right, if you're taking a big risk of death, have it be for the payoff of a useful mission. Not a practice flight where the payoff is simply that you didn't die.

Maakuth 8y ago

Here's a Wikipedia article about the abort modes. It probably would get pretty tense if you had to abort when the rocket started going through 'rapid unplanned disassembly', though. https://en.wikipedia.org/wiki/Apollo_abort_modes https://en.wikipedia.org/wiki/Apollo_abort_modes

lloeki 8y ago
> rapid unplanned disassembly Is that proper aerospace lingo, like "controlled flight into terrain"? https://en.wikipedia.org/wiki/Controlled_flight_into_terrain https://en.wikipedia.org/wiki/Controlled_flight_into_terrain
- SomeHacker44 8y ago
  As a pilot, CFiT is very descriptive. RUD sounds to my (layman’s) ear to be a nice way of saying “uncontrolled unplanned self destruction.” I could call an incident where a plane engine (on my plane) threatened to tear itself and the wing to bits because combustion became unbalanced, causing a vibration that had I not shut it down would have led to a rapid unplanned disassembly too, and likely not ended as well as the preventative.
- TeMPOraL 8y ago
  Yes. It roughly translates to "exploded, though we didn't want that". There's an equivalent term fof CFiT too - lithobraking. It's like aerobraking (using planet's atmosphere to shed some speed), except with rocks.
tragomaskhalos 8y ago
Similar protocols for the Shuttle of course; was in Gambia in 1990 and got chatting with some NASA folks just sitting round the pool at a nearby hotel - they told us they were there as there was a specific abort phase whereby the Shuttle would glide across the Atlantic and land at Banjul airport (whose runway NASA had paid to have extended for this purpose!); in that unlikely eventuality they would have to leap into action, otherwise it was a nice few days in the sun for them.
- QuotedForTruth 8y ago
  There were a lot of these runways across the Atlantic. I wonder how many at a time they staffed with people like the people you met. https://en.wikipedia.org/wiki/List_of_Space_Shuttle_landing_sites#Transoceanic_Abort_Landing_Sites https://en.wikipedia.org/wiki/List_of_Space_Shuttle_landing_...
  - tragomaskhalos 8y ago
    After posting I checked the dates from memory vs shuttle launch dates from Wikipedia, and this would have been some weeks before the launch ; so I wonder if in fact their job was to drop into the various emergency landing areas and just do a check that everything was lined up just in case; otherwise it'd be very costly to have teams in situ at all of them.
    - QuotedForTruth 8y ago
      The shuttle was a very expensive program! Each launch was something like $450 million. I wouldnt be surprised if they had small teams at 2 or 3 runways as contingency plans. If the shuttle landed some where they would definitely need help getting out of it and I doubt it would be much cheaper to keep locals trained and ready.
- Maakuth 8y ago
  Sadly the shuttle abort protocols were not effective for Challenger-like, catastrophic failure modes. My, admittedly layman's, understanding is that Apollo abort system would have been able to evacuate the crew in a number of pretty dire scenarios.
russdill 8y ago
Yes, I wrote a bit too quickly there. Pogo might, but doesn't generally shut down engines, it shakes the launch vehicle apart. Engines with out of control pogo oscillations could be commanded to shut down to avoid a boom.