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NASAglenn1267 karma

Send cash or check made out to NASA! :) (DH)

NASAglenn803 karma

For electric propulsion thrusters, to get the big payoff of such a high fuel efficiency propulsion system you need to operate them for a long period of time (measured in years). The key problem we face is designing a device to last as long as we need it and to prove that it has this life with margin. You can imagine that running a device for multiple years can be costly and delay implementation. If I could wave a magic wand I would make them last forever and be able to prove that it meets the life requirement with few resources. I might be biased though since I ran an 8 year thruster life test for 5 of those years! (DH)

NASAglenn528 karma

Ion propulsion technologies are low thrust compared to the chemical propulsion systems. This is the main reason why chemical propulsion systems are used to launch things (thrust to mass ratio is greater than 1). Ion propulsion is used only for access through space (once you get into orbit). The current technologies that are flying and are being invested in by NASA are at thrust levels a fraction of a pound or a few grams. Working in metric units, thrust levels range from hundreds of mN to a few N. This low thrust is applied for long periods of time to continually accelerate the vehicle. Power levels for thrusters doubles every 10 - 15 years so thrust levels should be double in about 10 years. Maybe 3 - 5 X in 50 years. (DH)

NASAglenn486 karma

To date we have been unsuccessful in accelerated life testing. Those tests uncovered failure mechanisms that were not observed in standard wear testing. (DH)

NASAglenn462 karma

Considering how highly everyone is talking about KSP (I've never played it), I might actually have a shot of convincing my boss it's critical software for my job :)

A lot of the work we do at Glenn is experimental, as opposed to simulation. I don't know too much about the software we use for orbital simulations, but developing codes to simulate the physics of the thrusters themselves is a big part of research. Experimental testing (and life testing) can get expensive, so an accurate simulation would save a lot of time and money. - RS