3
$\begingroup$

The complete version of Buran spacecraft would have had two engines that were not sufficient for take-off under own power.

Is it possible to say that if the aircraft is not capable of taking off under own power (not sufficient), it should not be capable of going around (assuming weight and other circumstances are the same)?

| improve this question | |
$\endgroup$
  • $\begingroup$ Depends on if the aircraft was capable of (any) climb rate at the airport density altitude at the time you would be attempting to go around. Since you are already flying, getting up to speed isn't the issue, the issue is gaining altitude without stalling (or hitting things when you are climbing too slow). $\endgroup$ – Ron Beyer Apr 28 '17 at 20:24
  • $\begingroup$ @mins The in-atmosphere test version had 2 jet engines installed. I don't believe the orbiter version would ever have the jet engines installed, I think that is where the OP may be confused. This (and the other Buran question) are borderline better on Space.SE. $\endgroup$ – Ron Beyer Apr 28 '17 at 20:43
  • 1
    $\begingroup$ @RonBeyer, according to wikipedia the in-atmosphere test version had four engines and was able to take off under it's own power. $\endgroup$ – Jan Hudec Apr 28 '17 at 22:05
  • $\begingroup$ @mins, Buran does not have a “main tank”, but a first stage rocket with engines mounted on that rocket. The orbiter has two engines that serve as second stage, although with rather small Δv of 66.7 m/s, and deorbit engines, with fuel inside the orbiter itself. Of course they would be out of fuel, or almost out, by the time of landing. $\endgroup$ – Jan Hudec Apr 28 '17 at 22:18
  • 1
    $\begingroup$ Please retract the landing flaps! $\endgroup$ – rbp May 2 '17 at 23:26
4
$\begingroup$

It really is something watching the Buran 'takeoff' versus 'liftoff'.

The answer is no. Given the same weight it should be roughly the same power needed. That is if we are calculating it from the point of rotation for a takeoff and point of initiating a go-around.

Given the same starting conditions—weight and velocity—both aircraft will have the same kinetic energy. If the takeoff / go-around is to 2,000 feet above starting condition, then the change will be the same gain in potential energy.

If they take the same time to reach that height, then it is the same power used. (Ignoring ground effect.)

The objective of the 2 engines would be to extend the glide distance for a space reentry, say if an incorrect calculation or unforeseen event caused the space glider to come short. A corrective action would need to be applied not close to the ground, but high enough to have a meaningful effect.

| improve this answer | |
$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.