Something I do not understand about the buran/energia system:<br />On that buran-energia website its says <i>"...the Buran-Energia is designed as a fully reusable shuttle system, that includes the four side 'Zenit' boosters and the main huge 'Energia' core super booster (Energia-T)...The Zenit boosters that strap on to the Energia core rocket are equipped with large parachute/retro rocket soft landing systems. The Energia core booster itself is designed to use such a system. This allows Energia and Zenit rockets to be recovered, refuelled, and re used at least ten times. It it worth noting, however, that the first flight of Buran-Energia in space did not take place with recoverable side or core booster rockets, but this was still in the development phase of the shuttle's life."</i> <br /><br />Is that true? <br />I allways thought that the energia rocket was lost and not reuseable (on its only two flights it was lost as a whole, core and boosters). <br />I can imagine that the zenit booster could have been upgraded with a parachute system to land like the STS-SRBs. <br />But the core rocket with the main engines too?<br />I understand it that the core energia rocket (a kind of ET with SSMEs attached) would provide thrust to a point in flight similar to the ET seperation on the STS. That means it would have nearly reached an orbit, and therefore a very high speed (almost the same speed as the orbiter, much higher than the boosters). <br />To land back like the boosters, it would need to do a kind of reentry procedure. That means it must get rid of the speed. <br />This could have happened either with aerobreaking (like all the capsules and the orbiters do), or with a kind of break-engine (or is there another option?). <br />In order to aerobreak it during reentry, the Energia core/main rocket would need a thermal protection system like an orbiter or a giant heatshield. <br />As far as I know there was no TPS and no heatshield on the Energia (and I can not imagine one). <br></br>