In article id,
lid says...

In sci.space.station message -
september.org, Sat, 16 Apr 2016 13:40:38, Jeff Findley
posted:

I really hope this helps. I'm an engineer, not a writer, so I'm used to
drawing things on a white board while describing them to other people.
If anything is unclear, just ask.

You could add that there are (IIRC) three recovery burns; one soon after
separation, one around atmosphere entry, and the single-engine landing
burn. IIRC, the earlier burns use three engines. I think the three
burns apply both to the back-to-land and the out-at-sea recoveries. You
will probably recall the details,

Yes, there are three burns after stage separation.

The first "kills" the horizontal velocity away from the cape. For the
case of a landing at the launch site, this burn is much longer and
actually reverses the horizontal velocity vector, so that the stage can
make it back to the cape.

The second burn happens right before/during reentry to slow the stage
down vertically, so it does not reenter the earth's atmosphere too fast
and burn up/break apart. I believe SpaceX found out they needed this
burn "the hard way" and had a stage or two not make it through reentry.

The final burn is the landing burn, which is quite tricky. The thrust
to weight ratio of the very nearly empty stage is greater than one even
with the one center engine firing at its lowest thrust setting. So, it
has to be timed so that it can throttle up, as needed, and still end up
with zero vertical velocity at the precise point in space when its
landing gear hit the landing pad at (hopefully) a low enough vertical
and horizontal velocity (nearly zero) so it doesn't go "splat" like it
has on a few landings.

This whole sequence has been successful exactly twice. Once on land,
and once on the barge. The first was on land and has been test fired
and partially disassembled (based on a picture Elon Musk Tweeted
yesterday showing the two stages in their new horizontal integration
facility located right before the ramp at KSC Pad 39-A (a former Saturn
V/shuttle pad which they are leasing from NASA).

The stage from the barge landing was transported on an over-sized load
trailer from Port Canaveral back to the same building yesterday. After
being moved from the barge to the port (vertically), it was inspected a
bit, the grid fins folded up, then its landing legs were removed. Two
cranes then lifted it, moved it into a horizontal position, then placed
it on the trailer for the trip back to KSC.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.