By Gennady MALYSHEV, Dr. Sc. (Technology), Moscow Aviation Institute
Research space vehicles weighing 1 ton and more are on their way out. Coming in their stead are smaller spacecraft with a payload of 50 to 400 kg. They are the trend-setters, so to speak. Now, what is the best way of launching them? We can put them in orbit by conventional methods with the use of heavy booster rockets like "Rokot", "Kosmos" and others. But does it pay? Economically and in efficiency?
Putting an artificial earth satellite into a pre-assigned orbit requires what we call the circular, or orbital velocity equal to 7.8 km/s. This means that the ground-launched carrier (booster) rocket should have a velocity of 9.5 km/s at the start, since the loss of the characteristic velocity in launching (due to gravitational, aerodynamic and thrust losses in the atmosphere) amounts to something like 1.7 km/s.
But there is a way out-air-launched hardware. A plane lifts a carrier rocket and payload to an altitude of 18 - 25 km. And off it goes! Now what do we gain by that? First, minor satellites and rocket planes can be orbited in all directions (azimuths) and in any latitudes. The launching mobility is increased, while the launching control can be effected from a carrier plane's console. The characteristic velocity losses at the start, say, at an altitude of 11 km will be down to 1.17 km/s; and should the "ceiling" be up to 21 km, the loss will be a mere 0.95 km/s, or nearly half of what we have in ground launchings. What you need is this: find an adequate plane and design a system "satellite (payload)/carrier rocket". To begin with, we chose the fighter plane MIG-31 S which has no analogs in the world. This machine can take a load to a distance of 1,500 km, which means it can carry out launchings at any latitude and in any azimuth. The aircraft can be employed as an air-borne launching complex for smaller space rockets with a payload of 100 - 200 kg at an arbitrary tilt. Besides, th ... Читать далее