FA+
Shop
356 submissions
This idea comes from reading about the Black Horse, a proposed design for a single stage to orbit reusable launch vehicle which takeoffs on jet engines with an empty oxidizer tank and is refueled in flight before igniting its rocket engine.
http://www.projectrho.com/public_ht.....d--Black_Horse
I 'simply' adapted part of the concept (specifically the Black Colt variant) to the soviet Tu-22 Blinder medium bomber, because it has jet engines on the tail which leave the fuselage free to be modified. The satellite launching rocket is carried under the fuselage, like the massive Kh-22 long-range anti-ship missile the plane was often equipped with.
http://www.projectrho.com/public_ht.....d--Black_Horse
I 'simply' adapted part of the concept (specifically the Black Colt variant) to the soviet Tu-22 Blinder medium bomber, because it has jet engines on the tail which leave the fuselage free to be modified. The satellite launching rocket is carried under the fuselage, like the massive Kh-22 long-range anti-ship missile the plane was often equipped with.
Category Designs / Abstract
Species Unspecified / Any
Size 1070 x 518px
File Size 160.2 kB
Listed in Folders
Ah oui, stratolaunch, c'est vrai que je n'en ai plus vu de nouvelles depuis un certain temps !
C'est marrant que tu sortes ce concept, parce que à peine quelques heures avant de le lire, hier, je m'intéressais à l'histoire du Super Constellation, qui m'a amené à celle du Tristar, qui m'a amené... à ceci :
https://fr.wikipedia.org/wiki/Lockh.....teurs_spatiaux
en fait, je ne savais pas qu'on avait réellement utilisé un avion aussi "vieux" pour ce genre de missions. Mais il me semble avoir vu qu'on avait étudié, et même peut-être bien essayé, de lancer un micro-satellite à partir d'un F-15, non ? Je ne sais pas pourquoi, j'ai cette image en tête...
C'est marrant que tu sortes ce concept, parce que à peine quelques heures avant de le lire, hier, je m'intéressais à l'histoire du Super Constellation, qui m'a amené à celle du Tristar, qui m'a amené... à ceci :
https://fr.wikipedia.org/wiki/Lockh.....teurs_spatiaux
en fait, je ne savais pas qu'on avait réellement utilisé un avion aussi "vieux" pour ce genre de missions. Mais il me semble avoir vu qu'on avait étudié, et même peut-être bien essayé, de lancer un micro-satellite à partir d'un F-15, non ? Je ne sais pas pourquoi, j'ai cette image en tête...
Pour le F-15, il s'agissait de tests d'un missile anti-satellite :
https://en.wikipedia.org/wiki/McDon.....tellite_trials
En revanche, il existe un projet Dassault-CNES pour employer un Rafale comme lanceur de satellite :
https://en.wikipedia.org/wiki/Aldeb.....)#MLA-Trimaran
https://www.secretprojects.co.uk/th.....launcher.5583/
https://en.wikipedia.org/wiki/McDon.....tellite_trials
En revanche, il existe un projet Dassault-CNES pour employer un Rafale comme lanceur de satellite :
https://en.wikipedia.org/wiki/Aldeb.....)#MLA-Trimaran
https://www.secretprojects.co.uk/th.....launcher.5583/
Pour compléter la liste, la CIA avait pour projet d'utiliser le A-12 (prédécesseur du SR-71) pour lancer des satellites :
https://www.thedrive.com/the-war-zo.....nch-mothership
https://www.thedrive.com/the-war-zo.....nch-mothership
Interesting suggestion, I only knew of the Oberth effect as working while decreasing altitude to trade potential energy for kinetic energy. On the other hand, you can use three burns (called the Edelbaum maneuver) to reach escape velocity more efficiently than with the two-burns Oberth manouver, as detailed in this paper : https://arxiv.org/pdf/2010.14997.pdf
When raising orbit, it is always best to burn the propellant as low as possible, so you don't have to give it any more potential energy than necessary. This is true even for orbits that intersect the ground. Concider for example a two-stage sounding rocket with both stages having delta-V of 1 km/s and high thrust. You fire the 1st stage and launch the rocket towards zenith. Ignoring drag, the apogee will be about 50 km. At apogee, just as the rocket stops, you fire the 2nd stage. Now the rocket has again 1 km/s of upward speed, which gives it a final apogee of ~100 km. On the other hand, if you burn both stages immediately after lift-off, the rocket will reach initial speed of 2 km/s and apogee of ~200 km.
In the case of an orbital rocket launched from a sub-orbital spaceplane there is also another reason to release it early: time. If the rocket is still going up when it fires it engines, it will have more time to gain horizontal velocity and less need to burn diagonally up to prevent falling back before it reaches orbital velocity. Less thrust is needed, meaning possibly a smaller and lighter engine.
I was familiar with idea of Edelbaum maneuver, but didn't know it had a name. Thanks for the paper, I had actually wondered if four or more burns would be more efficient when escaping and now I know the answer.
In the case of an orbital rocket launched from a sub-orbital spaceplane there is also another reason to release it early: time. If the rocket is still going up when it fires it engines, it will have more time to gain horizontal velocity and less need to burn diagonally up to prevent falling back before it reaches orbital velocity. Less thrust is needed, meaning possibly a smaller and lighter engine.
I was familiar with idea of Edelbaum maneuver, but didn't know it had a name. Thanks for the paper, I had actually wondered if four or more burns would be more efficient when escaping and now I know the answer.
Comments