2 ms·

> In no case have they built a craft with no specific goal, then declared it's operational life expectancy, and then went and found a mission to do with it. I

> In no case have they built a craft with no specific goal, then declared it's operational life expectancy, and then went and found a mission to do with it. I don't think the message you responded to said that they built the craft then declared the operational life expectancy. NASA could have designated a science goal which needed 22 flights, and had the same cost, time and mass budget associated with it. Clearly that goal would have been achievable with some probability given that it was achieved. They didn't. The comment in question is speculating about the reasons why NASA might have chosen 5 flight as the target instead of 22 or 222.

bdamm 5y ago
It's not the case that they could guarantee 22 flights for the same cost, time, and mass budget. We only know that this design worked after the fact, they didn't have that information in advance. Also, this design may only have achieved 22 flights by pure luck; maybe radiation hasn't struck a key microchip yet, or maybe the dust hasn't degraded the rotor motors as much as expected because there hasn't been as much dust as expected.