3 ms·

What portion of the fuel in the rocket is burned to slow down and land?

• duskwuff 12y ago
  Very little, actually. Most of the weight of the rocket is fuel; once it's hit its target altitude, it weighs practically nothing, and takes very little fuel to land.
  • motoboi 12y ago
    It weights so little that, in fact, they have to use just one engine, and throttle it down to its minimum.
• lmm 12y ago
  In all seriousness, try it in Kerbal Space Program (with one of the aerodynamic mods if you want to be more accurate); I don't have hard numbers but I'd guess something like 2-5%. Fuel needed for a particular acceleration is proportional to the mass (duh), so the amount of fuel needed for the same delta-v of an almost-empty first stage is much, much less than for one with a second stage on top.
• shasheene 12y ago
  Estimates are overall payload to orbit is reduced by around 30% with reusability. Dry land landings are more economical for SpaceX, but have further reduced payload to orbit. I understand the portion of total fuel required can be worked out from that and knowing a little about the rocket specifications.
• jccooper 12y ago
  It was said at some point to be 3%. Anywhere in 2-5% is plausible. Doesn't take much; a nearly-empty stage weighs next to nothing in comparison to a fully-loaded stack. In fact, even with only one engine at minimum throttle, the the F9R-1 stage still has a thrust significantly higher than its weight. Thus the "hover-slam" description of their landing mode: they try to slow down to just above 0 at just the right altitude. Quite a bit of precision required.