How close was this to a production prototype? What I mean was, could they have really built this, had they had the go ahead; Or was this just an academic exercise for the slide rule boys? I am really very curious about these engines. It seems to me that they might be the only way we make the jump from Shuttle/Apollo Era thinking.
David G wrote:
“How close was this to a production prototype?”
They did get the NERVA engine to run in prototype form, it’s just they could never figure out what to use it for without something like a commitment to a manned Mars mission after Apollo.
Weight of the radiation shielding for manned use also worked against the high specific impulse of the engine.
A evolved design that appeared to have even higher isp by using laminar LH2 flow through very small channels in the reactor elements, called “Dumbo”, never got fully developed.
The last (known) attempt at a engine of this type was Project Timberwind.
Could these engines have been used for an Earth surface launch, or would they more likely be found in a space only application. And what sort of lifespan do these engines have, are they used once and then thrown away.
NERVA engines, especially early ones like this, had far too low of a thrust/weight ratio to be used for launch vehicles. Operational life of a NERVA could be measured in hours, far longer than any likely engine burn; most vehicle designs called for them to be used only once, then discarded. Before being turned on, a NERVA would not be particularly radioactive… but afterwards it most assuredly would be, so rather than have a dangerous radioactive source stuck to the ship, the general plan called for them to be ejected.
THX
you got more ?
Ah, if only they’d built it…
> you got more ?
Rather a lot more.
Question;
How close was this to a production prototype? What I mean was, could they have really built this, had they had the go ahead; Or was this just an academic exercise for the slide rule boys? I am really very curious about these engines. It seems to me that they might be the only way we make the jump from Shuttle/Apollo Era thinking.
David G wrote:
“How close was this to a production prototype?”
They did get the NERVA engine to run in prototype form, it’s just they could never figure out what to use it for without something like a commitment to a manned Mars mission after Apollo.
Weight of the radiation shielding for manned use also worked against the high specific impulse of the engine.
A evolved design that appeared to have even higher isp by using laminar LH2 flow through very small channels in the reactor elements, called “Dumbo”, never got fully developed.
The last (known) attempt at a engine of this type was Project Timberwind.
Could these engines have been used for an Earth surface launch, or would they more likely be found in a space only application. And what sort of lifespan do these engines have, are they used once and then thrown away.
NERVA engines, especially early ones like this, had far too low of a thrust/weight ratio to be used for launch vehicles. Operational life of a NERVA could be measured in hours, far longer than any likely engine burn; most vehicle designs called for them to be used only once, then discarded. Before being turned on, a NERVA would not be particularly radioactive… but afterwards it most assuredly would be, so rather than have a dangerous radioactive source stuck to the ship, the general plan called for them to be ejected.