Good launch, staging, and entry burn.
Landing burn begun.
WOW GREAT LANDING!
Had a LOT of shaking when the landing burn began. Perhaps related to going Transsonic, lots of turbulence to begin wit,h and the grid fins do not work well in that phase. They might need to tweak the control feedback/authority values for that phase. I do not recall shaking that bad from an onboard camera view, so this may be related to the improved grid fin performance/behaviour. Also do not recall seeing a grid fin move back and forth and back and forth to the extent that the left one did.
That great side by side photo that dhbarr posted, the apparent scalloping seems to indicate a very sharp leading edge (the edge once deployed, coming down), and the flat surface we see is the trailing edge. Like a wedge cross-section. Wedges work well at supersonic speeds. And flat plates do not, which is what the original F9 grid fins used.
WHOA! I knew the landing looked so soft. Well, watched it again. TOO soft - it never landed before engine shutdown!
As you may recall, the Merlin engine's minimum throttle is still more thrust than the F9 weighs during landing. So if during landing, it comes to zero downward velocity and has NOT touched down yet, it is going to go back UP. I think it may have reached zero velocity a foot or more above the deck ( and would have gone back up if the engine had not shut down). Because the legs did NOT move any to indicate they were touching the deck, when the engine shut down. Then you can see the rocket drop a bit and the leg tips move out as they contact the deck and finally support the weight of the rocket. The more I watch it the more I'm sure that's what happened. AFAIK, this has not happened before. But well within the structural design to fall from not too high
This animated gif I found shows the landing (I later found out after posting this, that others on NSF and elsewhere noticed this too). But it's more obvious in watching the youtube webcast on full screen.
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Pretty tricky business landing at sea, the barge even if kept perfectly flat, it will still be going up and down. So which height will you go for? Assuming you have one engine running its at min power there is no way you can adjust for a slightly lower barge at the exact instance you happen' it's a case of cut the power and hope it's not too high. Of course the opposite can be an issue too, if you aim even lower but the barge hits a big wave it's going to be higher than you expect and you'll still be on the way down when you hit the barge coming up. Fortunately in that case you may have enough time to tweak the thrust a bit.
Also the transition of weight onto the barge isn't zero weight instantly changing to full weight, with the thrust bearing down on the barge it is actually full supporting the weight of the rocket before it lands. Not sure how much the rocket weighs compared to the barge but the barge will be forced into the water before and after landing. But with the 1 foot drop the weight is momentarily off the barge it should in fact rise to some extent before the rocket falls on it.