For example... It is generally accepted that you risk the least amount of personnel...
Or to say the same thing another way: there's always more you could have done to prevent an accident, but at some point you have to fly.
Quote from: Rocket Science on 11/08/2014 08:28 pmFor example... It is generally accepted that you risk the least amount of personnel...I really wish you'd speak in complete sentences. You risk the least amount of personnel to do what? You can risk no personnel by doing nothing - just send 'em all home. If your goal is to build a fighter plane before the war is over you're likely to be willing to accept more risks, and find more volunteers willing to take those risks, than if you're trying to build a new board game or whatever. Nothing ventured, nothing gained.
We are approaching the point where purely autonomous or at least remotely-operated vehicles might be developed and tested at a cost not significantly more than the cost of developing human-operated vehicles. Obviously SpaceX took this approach with Dragon.
How is that "not significantly more"?
I think as everything is FBW now
It's a subtle point. I don't think you are suggesting that if the cargo on Dragon Flight 1 had included a human instead of a wheel of cheese then the costs SpaceX incurred to reach that point would have been less.
You'd do something like the Orion EFT-1 flight to test the heat shield - a simple suborbital slam into the atmosphere. Then you'd fly the vehicle with crew all the way to the station.
Quote from: QuantumG on 11/08/2014 09:08 pmHow is that "not significantly more"?It's a subtle point. I don't think you are suggesting that if the cargo on Dragon Flight 1 had included a human instead of a wheel of cheese then the costs SpaceX incurred to reach that point would have been less. Are you suggesting there's something a human pilot of Dragon Flight 1 could have provided which would have allowed them to fly the mission at a lower cost? I believe Vostok also flew first without a pilot. So is Mercury the comparison? It needed a pilot, and eliminating that need would have been a hit to development both in terms of cost and schedule....Quote from: Space Ghost 1962 on 11/08/2014 09:10 pmI think as everything is FBW nowNot everything reaching space is fly-by-wire now. At least it wasn't ten years ago when SpaceShipOne flew.
Mercury flew unmanned until Ham because he had "The Right Stuff"...
Quote from: Rocket Science on 11/08/2014 10:21 pmMercury flew unmanned until Ham because he had "The Right Stuff"...Chimps were flown because the effects of spaceflight on humans wasn't well understood. They didn't actually control anything.
No, really?
You're humorously pointing out that Mercury too flew without pilot control before its first piloted flight.
Quote from: funkyjive on 12/09/2014 02:55 amQuote from: Kabloona on 12/08/2014 07:48 pmThe only thing that could have gone wrong was pilot error, and this was apparently a rare case of a well-trained, experienced test pilot doing one thing wrong at the worst possible time, something that can never be fully designed out of a system.A computer would fully eliminate that possibility.He discusses why that option was rejected here:Quote from: Marc J. Zeitlin-Have automation question pilot decision.You know that I am usually on your side with respect to automation capabilities. In this case, the design philosophy of the aircraft (given that it would NOT be able to have hundreds of very incremental test flights during which the automation systems would be wrung out, as these systems WILL have bugs/errors in them) was to have everything possible be manual, non-boosted and non-automated. We made concessions in certain areas where it was not possible to manually control things (pitch control while supersonic, for instance), but in general, the philosophy was to rely on the pilots and intensive simulation of every failure mode we could think of given the very small number of flights that could be flown, given the cost of flying a glide flight, much less a powered flight.“Are you sure you want to destroy the plane by deploying at this time?” We have multiple sensors that all agree he’s making big mistake...Again, if it would be possible, as in the development of a Gulfstream bizjet, to have zillions of incremental test flights, we might have gone that route. But our judgement was that we would be more successful relying on pilots and extremely intensive training, as Scaled had been successful over its 30 year history without a fatality in a test flight.https://groups.google.com/forum/m/#!msg/cozy_builders/YOnxrd26tXc/3OmYdxvqF_AJ
Quote from: Kabloona on 12/08/2014 07:48 pmThe only thing that could have gone wrong was pilot error, and this was apparently a rare case of a well-trained, experienced test pilot doing one thing wrong at the worst possible time, something that can never be fully designed out of a system.A computer would fully eliminate that possibility.
The only thing that could have gone wrong was pilot error, and this was apparently a rare case of a well-trained, experienced test pilot doing one thing wrong at the worst possible time, something that can never be fully designed out of a system.
-Have automation question pilot decision.You know that I am usually on your side with respect to automation capabilities. In this case, the design philosophy of the aircraft (given that it would NOT be able to have hundreds of very incremental test flights during which the automation systems would be wrung out, as these systems WILL have bugs/errors in them) was to have everything possible be manual, non-boosted and non-automated. We made concessions in certain areas where it was not possible to manually control things (pitch control while supersonic, for instance), but in general, the philosophy was to rely on the pilots and intensive simulation of every failure mode we could think of given the very small number of flights that could be flown, given the cost of flying a glide flight, much less a powered flight.“Are you sure you want to destroy the plane by deploying at this time?” We have multiple sensors that all agree he’s making big mistake...Again, if it would be possible, as in the development of a Gulfstream bizjet, to have zillions of incremental test flights, we might have gone that route. But our judgement was that we would be more successful relying on pilots and extremely intensive training, as Scaled had been successful over its 30 year history without a fatality in a test flight.