4 ms·

Here's the video cued up to the booster landings: https://youtu.be/TXMGu2d8c8g?t=1643 https://youtu.be/TXMGu2d8c8g?t=1643 with the main core landing a few minut

Here's the video cued up to the booster landings: https://youtu.be/TXMGu2d8c8g?t=1643 https://youtu.be/TXMGu2d8c8g?t=1643 with the main core landing a few minutes later. If it's not obvious, the main core landing was much harder this time around, because of how fast it was going due to the two boosters imparting a lot of extra speed on it before they separated. If you think about it, it'll have somewhere between 1x and 3x the velocity of a normal Falcon 9 core

gnode 8y ago
It doesn't necessarily make it harder. There's a burn to slow the booster down for re-entry, and having the side boosters do a lot of the work means more fuel / delta-v can be saved to slow the core booster. The FH is apparently capable of 8,000kg in a reusable GTO launch ( https://en.wikipedia.org/wiki/Falcon_Heavy#Capabilities https://en.wikipedia.org/wiki/Falcon_Heavy#Capabilities ), and this satellite was only 6,000kg. So it looks like there would be plenty of fuel available to slow the core down well below the survivable maximum.
- ravedave5 8y ago
  It's the same steps but it is harder, the center booster was going faster than any other core that has been recovered. The recovery itself was ~300 miles further out than any other recovery. Swinging a bat at a 10mph ball is the same technology as swinging at a 90mph one. I don't think anyone would say that they were equally as easy.
  - gnode 8y ago
    My point is that it's less a question of technical difficulty / tolerance, but more fuel / delta-v / mass cost. In the case of a bat swing, to bat the ball faster, your muscles need to be stronger, and the ball and bat need to withstand greater pressures. In the case of a vehicle travelling through space / thin atmosphere, it only needs more fuel to burn to slow it down. Analogously, you don't parallel park a car from 70mph, having travelled somewhere on a highway. Here's a graph a booster's speed over time, showing the reentry burn: https://i.stack.imgur.com/xFYIh.png https://i.stack.imgur.com/xFYIh.png ( from https://space.stackexchange.com/questions/20246/what-is-this-debris-on-the-crs-10-reentry-at-t630 https://space.stackexchange.com/questions/20246/what-is-this... )

gnode 8y ago

It doesn't necessarily make it harder. There's a burn to slow the booster down for re-entry, and having the side boosters do a lot of the work means more fuel / delta-v can be saved to slow the core booster. The FH is apparently capable of 8,000kg in a reusable GTO launch ( https://en.wikipedia.org/wiki/Falcon_Heavy#Capabilities https://en.wikipedia.org/wiki/Falcon_Heavy#Capabilities ), and this satellite was only 6,000kg. So it looks like there would be plenty of fuel available to slow the core down well below the survivable maximum.

ravedave5 8y ago
It's the same steps but it is harder, the center booster was going faster than any other core that has been recovered. The recovery itself was ~300 miles further out than any other recovery. Swinging a bat at a 10mph ball is the same technology as swinging at a 90mph one. I don't think anyone would say that they were equally as easy.
- gnode 8y ago
  My point is that it's less a question of technical difficulty / tolerance, but more fuel / delta-v / mass cost. In the case of a bat swing, to bat the ball faster, your muscles need to be stronger, and the ball and bat need to withstand greater pressures. In the case of a vehicle travelling through space / thin atmosphere, it only needs more fuel to burn to slow it down. Analogously, you don't parallel park a car from 70mph, having travelled somewhere on a highway. Here's a graph a booster's speed over time, showing the reentry burn: https://i.stack.imgur.com/xFYIh.png https://i.stack.imgur.com/xFYIh.png ( from https://space.stackexchange.com/questions/20246/what-is-this-debris-on-the-crs-10-reentry-at-t630 https://space.stackexchange.com/questions/20246/what-is-this... )