3 ms·
Rail guns have a lot of problems for orbital insertion from an atmosphere: 1. Storing the energy to accelerate the payload. 2. Not accelerating the payload so
by sparker72678 6y ago
Rail guns have a lot of problems for orbital insertion from an atmosphere:
1. Storing the energy to accelerate the payload.
2. Not accelerating the payload so quickly that it breaks apart.
3. Thermal heating from atmospheric drag.
4. The energy required to overcome atmospheric drag itself.
5. Strength/size of materials to build the sled and contain a payload with that much momentum.
My understanding is that 3 & 4 on this list tend to make rail guns a non-starter on earth.
- pmoriarty 6y agoWhy are 3 & 4 different more challenging for railguns than other means of propulsion?
- rbanffy 6y agoOn a railgun you'll have to pass orbital speed by the end of the rail, because, from that point on, you will only lose speed to the atmosphere and you have most of it still above the end of the rail. Rockets, OTOH, go up vertical for most of the atmosphere and then get horizontal in order to get to orbital speed, preferably where there is little or no atmosphere. You'll also need to carry some form of propulsion to circularize your orbit, unless you are aiming for escape velocity, in which case your speed at the end of the rail will have to be much higher. Whatever engine you have will need to survive the acceleration.
- hinkley 6y ago> Rockets, OTOH, go up vertical for most of the atmosphere and then get horizontal in order to get to orbital speed, preferably where there is little or no atmosphere. And yet most launch systems have to throttle down the engines during the transition between the two, because the atmosphere is still just a bit too thick to safely plow through it at full tilt.