Here’s a full look at the countdown and ascent milestones for tonight’s launch, targeted for 8:28 EST from Launch Complex 39A at NASA’s Kennedy Space Center in Florida. All times are approximate:
COUNTDOWN
Hr/Min/Sec Event
– 00:38:00 SpaceX Launch Director verifies go for propellant load
– 00:35:00 RP-1 (rocket grade kerosene) loading begins
– 00:35:00 1st stage LOX (liquid oxygen) loading begins
– 00:16:00 2nd stage LOX loading begins
– 00:07:00 Falcon 9 begins pre-launch engine chill
– 00:05:00 Dragon transitions to internal power
– 00:01:00 Command flight computer to begin final prelaunch checks
– 00:01:00 Propellant tanks pressurize for flight
– 00:00:45 SpaceX Launch Director verifies go for launch
– 00:00:03 Engine controller commands engine ignition sequence start
– 00:00:00 Falcon 9 liftoff
LAUNCH, LANDING, AND DRAGON DEPLOYMENT
Hr/Min/Sec Event
-00:01:12 Max Q (moment of peak mechanical stress on the rocket)
-00:02:17 1st stage main engine cutoff (MECO)
-00:02:21 1st and 2nd stages separate
-00:02:28 2nd stage engine starts
-00:02:34 Boostback Burn Starts
-00:03:28 Boostback Burn Ends
-00:06:10 1st stage entry burn starts
-00:06:22 1st stage entry burn ends
-00:07:19 1st stage landing burn starts
-00:07:36 1st stage landing
-00:08:33 2nd stage engine cutoff (SECO-1)