Jonathan_S wrote:darrell wrote:oops, so like shuttles the viper is a dual craft able to operate on impeller in space, but since there is a limit to how low you can go with an impeller wedge, at treetop level it would have to operate on countergrav.
While it should be able to operate at 800g's in space under impeller, it would be limited to 50g's at treetop level under countergrav. what the minimum height is for impellers I don't know, but would be surprised if it was not somewhere on the order of 50-100KM.
A sting ship like a viper should be significantly smaller than a pinnace (less range, no need for cargo/passenger capacity) so it should have a smaller wedge. But I don't know how much smaller.
On the one hand impeller powered man portable missiles, with their tiny wedges, can be fired from ground level and ignite those (brief lived) wedges seemingly with 20 feet or so of the ground.
On the other hand pinnaces and shuttles seem to normally shut down their impellers about the time they hit atmosphere; switching over to air-breathing turbines and countergrav.
100 km is high enough that the stingship would basically be outside the atmosphere. On the one hand that seems an excessive amount of ground clearance, but it does limit the effects of a vehicle sized wedge's grav shear on the atmosphere. Also, the top speed within atmosphere is probably temperature limited; and even if the hull and exposed hardware can take the heat it's got to be hard to see and target through the compression plasma of greater than hypersonic speeds. So it would seem you can't use a wedge's acceleration for long in atmo. So maybe it is restricted to transorbital use.
(Though if so you'd think you could build an even higher performance atmo only stingship that omitted the mass and volume of the impellers)
A lot of what is being discussed here has been discussed in the Topic relating to Sting Ships. As for using wedges close to the ground, manportable wedge equipped surface to air missiles are described in several books but they would be like the Manpads used today like Starstreak. They can accelerate to up to Mach 4 close to the ground but no aircraft could fly supersonically, & certainly not at Mach 4, that low down in the atmosphere. I could not see them using a wedge that close to the ground; supposed it brushed the ground whilst manoeuvring?
