SpaceX’s Falcon 9 rocket is set for liftoff from Cape Canaveral on Friday afternoon, heading due east over the Atlantic Ocean to deliver the BulgariaSat 1 communications satellite into orbit 35 minutes later.
The 229-foot-tall (70-meter) rocket is poised for launch from pad 39A at NASA’s Kennedy Space Center in Florida at 2:10 p.m. EDT (1810 GMT) Friday at the opening of a two-hour launch window.
Perched atop the rocket is the BulgariaSat 1 communications satellite, a spacecraft made by Space Systems/Loral, ready to beam television programming across Bulgaria and neighboring countries in the Balkans. The rocket will place the satellite into a high-altitude “supersynchronous” transfer orbit.
The timeline below outlines the launch sequence for the Falcon 9 flight with BulgariaSat 1, SpaceX’s second launch with a previously-flown first stage booster.
Data source: SpaceX
T-0:00:00: Liftoff
After the rocket’s nine Merlin engines pass an automated health check, hold-down clamps will release the Falcon 9 booster for liftoff from pad 39A.
T+0:01:10: Mach 1
The Falcon 9 rocket reaches Mach 1, the speed of sound, as the nine Merlin 1D engines provide more than 1.7 million pounds of thrust.
T+0:01:19: Max Q
The Falcon 9 rocket reaches Max Q, the point of maximum aerodynamic pressure.
T+0:02:36: MECO
The Falcon 9’s nine Merlin 1D engines shut down.
T+0:02:40: Stage 1 Separation
The Falcon 9’s first stage separates from the second stage moments after MECO.
T+0:02:47: First Ignition of Second Stage
The second stage Merlin 1D vacuum engine ignites for a nearly 6-minute burn to put the rocket and BulgariaSat 1 into a preliminary parking orbit.
T+0:03:40: Fairing Jettison
The 5.2-meter (17.1-foot) diameter payload fairing jettisons once the Falcon 9 rocket ascends through the dense lower atmosphere. The 43-foot-tall fairing is made of two clamshell-like halves composed of carbon fiber with an aluminum honeycomb core.
T+0:06:19: Stage 1 Entry Burn
A subset of the first stage’s Merlin 1D engines ignite for an entry burn to slow down for landing. A final landing burn will occur just before touchdown.
T+0:08:31: Stage 1 Landing
The Falcon 9 rocket’s first stage booster touches down on SpaceX’s drone ship in the Atlantic Ocean.
T+0:08:38: SECO 1
The second stage of the Falcon 9 rocket shuts down after reaching a preliminary low-altitude orbit. The upper stage and BulgariaSat 1 begin a coast phase scheduled to last more than 18 minutes before the second stage Merlin vacuum engine reignites.
T+0:27:08: Second Ignition of Second Stage
The Falcon 9’s second stage Merlin engine restarts to propel the BulgariaSat 1 communications satellite into a supersynchronous transfer orbit.
T+0:28:13: SECO 2
The Merlin engine shuts down after a short burn to put the BulgariaSat 1 satellite in the proper orbit for deployment.
T+0:34:55: BulgariaSat 1 Separation
The BulgariaSat 1 satellite separates from the Falcon 9 rocket in a supersynchronous transfer orbit.
The United Launch Alliance Delta 4-Heavy rocket, standing 235 feet tall and weighing 1.6 million pounds fully fueled, unleashes 2.1 million pounds of thrust from the three RS-68A main engines at 1:51 p.m. EDT (1751 GMT) today to launch from Cape Canaveral on NROL-37.
The launch of a light-class booster by Rocket Lab, a U.S.-New Zealand company aiming to provide rides to orbit for small satellites, has been delayed to early next year after technical reviews, repairs and unfavorable weather combined to keep the test flight grounded this week.
