"we did all the right things to win that project, but it was one of those times where you get wound up in winning and sometimes it's a good idea to kind of stop and think just how possible the thing that you were about to try and win really was"
"no small rocket had ever launched anything outside Earth's gravity well"
"so the first thing we needed to do is double the performance of the rocket"
"normally the approach [on radiation hardening for missions beyond LEO] is really really expensive microprocessors that are radiation hard and lots and lots of really thick shielding. Now of course we couldn't afford the the really really expensive processors and they take too long anyway and we didn't have the mass to put really really heavy shielding"
"we ended up with was an amazing super high Performance [3rd stage] Engine but it had a 40° celsus window of operation so you know at plus 40° from its nominal operating point it explodes"
"we couldn't get our FAA license through in time to make the launch window so we had to move the launch from uh America to New Zealand which doesn't sound like a big deal except for the fact that we had to build an entire facility to manage those really tricky NASA propellants ... these facilties is are like a three-year build we had nine months"
"normally when you build a spacecraft of this complexity you allow in your project plan between 1 and 3 months of commissioning time because it's a three AIS stabilized platform meaning it's got reaction wheels and star trackers and T rods and you know gimbal engines and all the rest of it so normally what you would do is you would turn the spacecraft on it goes into sun
pointing mode and that's your safe mode and your stable mode and then you would slowly bring up each system one system at a time very methodically until the whole spacecraft is is is operational. ... we had a window of around about 6 to 8 minutes before we had to turn that thing on point it in the right direction and fire the engine for the first time and get it get it out of the soup into a stable orbit"
"as I mentioned before there was a 40° C delta between the engine running running normally and the engine exploding. well it turns out that we would burn the
engine and at the end of the burn the engine temperature would be 5° higher than when it started ... on the second burn, oh we're up 10°, oh that'll stop soon, third burn up 15, uh this is keeping on going. So that means on the 8th burn the engine would explode and that would be that would be a little bit depressing"
Lots more quotes along these lines. Amazing they pulled it all off.
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[ 4.1 ms ] story [ 9.3 ms ] thread"we did all the right things to win that project, but it was one of those times where you get wound up in winning and sometimes it's a good idea to kind of stop and think just how possible the thing that you were about to try and win really was"
"no small rocket had ever launched anything outside Earth's gravity well"
"so the first thing we needed to do is double the performance of the rocket"
"normally the approach [on radiation hardening for missions beyond LEO] is really really expensive microprocessors that are radiation hard and lots and lots of really thick shielding. Now of course we couldn't afford the the really really expensive processors and they take too long anyway and we didn't have the mass to put really really heavy shielding"
"we ended up with was an amazing super high Performance [3rd stage] Engine but it had a 40° celsus window of operation so you know at plus 40° from its nominal operating point it explodes"
"we couldn't get our FAA license through in time to make the launch window so we had to move the launch from uh America to New Zealand which doesn't sound like a big deal except for the fact that we had to build an entire facility to manage those really tricky NASA propellants ... these facilties is are like a three-year build we had nine months"
"normally when you build a spacecraft of this complexity you allow in your project plan between 1 and 3 months of commissioning time because it's a three AIS stabilized platform meaning it's got reaction wheels and star trackers and T rods and you know gimbal engines and all the rest of it so normally what you would do is you would turn the spacecraft on it goes into sun pointing mode and that's your safe mode and your stable mode and then you would slowly bring up each system one system at a time very methodically until the whole spacecraft is is is operational. ... we had a window of around about 6 to 8 minutes before we had to turn that thing on point it in the right direction and fire the engine for the first time and get it get it out of the soup into a stable orbit"
"as I mentioned before there was a 40° C delta between the engine running running normally and the engine exploding. well it turns out that we would burn the engine and at the end of the burn the engine temperature would be 5° higher than when it started ... on the second burn, oh we're up 10°, oh that'll stop soon, third burn up 15, uh this is keeping on going. So that means on the 8th burn the engine would explode and that would be that would be a little bit depressing"
Lots more quotes along these lines. Amazing they pulled it all off.