[Spaceships] Ram-Rockets and Air-Rams

[Agemegos]

Originally Posted by Diomedes

In Spaceships, nuclear and antimatter rockets can be built with an air-ram for atmospheric maneuvering, for ×5 to cost. How much thrust should such a ram have, and what cost should be appropriate for a pure air ram?

Going by the rules alone there is no effect on thrust. But really the thrust ought to be multiplied by SQRT {(average molecular mass of atmosphere) / 2} for the same reason that thrust is multiplied by 3 when using water. Earth's atmosphere has an average molecular mass of 28.8, so thrust ought to be multiplied by 3.8.

In my opinion the cost of ram-rockets is way too high. It tends to imply that air air intake and compressor cost more than an entire shuttlecraft, despite the fact that a shuttlecraft with a jet engine has to include these things and is much cheaper.

[Diomedes]

Originally Posted by Brett

Going by the rules alone there is no effect on thrust. But really the thrust ought to be multiplied by SQRT {(average molecular mass of atmosphere) / 2} for the same reason that thrust is multiplied by 3 when using water. Earth's atmosphere has an average molecular mass of 28.8, so thrust ought to be multiplied by 3.8.

In my opinion the cost of ram-rockets is way too high. It tends to imply that air air intake and compressor cost more than an entire shuttlecraft, despite the fact that a shuttlecraft with a jet engine has to include these things and is much cheaper.

My solution was to apply the ×5 cost modifier to the fusion reactor system, declare thrust to be 1G and call it a day.

[martinl]

Originally Posted by Brett

In my opinion the cost of ram-rockets is way too high. It tends to imply that air air intake and compressor cost more than an entire shuttlecraft, despite the fact that a shuttlecraft with a jet engine has to include these things and is much cheaper.

It may be possible that Mr. Pulver was implying a complete redesign of the engine, to tough dual-use specifications, was required.

[davester65]

Originally Posted by martinl

It may be possible that Mr. Pulver was implying a complete redesign of the engine, to tough dual-use specifications, was required.

X5 is awfully high though. Especially where some of these engines are pretty pricey to begin with. I can see x2, but x5 seems too much.