September 26, 2017

Falcon 9 launch timeline with Intelsat 35e

NOTE: Updated after scrubs Sunday and Monday.

SpaceX’s Falcon 9 rocket is set for liftoff from Cape Canaveral on Wednesday evening, heading due east over the Atlantic Ocean to deliver the Intelsat 35e communications satellite into orbit 32 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 7:37 p.m. EDT (2337 GMT) Wednesday at the opening of a 58-minute launch window.

Perched atop the rocket is the Intelsat 35e communications satellite, a spacecraft made by Boeing in El Segundo, California, ready to beam video, broadband Internet and data across the Americas, the Caribbean, the Atlantic Ocean and Europe.

The 14,905-pound (6,761-kilogram) spacecraft is the heaviest geostationary satellite ever launched by SpaceX, requiring all of the Falcon 9’s fuel capacity to reach an elliptical transfer orbit high above Earth. The heavy payload will prevent the Falcon 9’s first stage from attempting a landing.

The timeline below outlines the launch sequence for the Falcon 9 flight with Intelsat 35e, SpaceX’s 10th mission of the year, and the 38th Falcon 9 launch since the first version of the rocket debuted in June 2010.

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+0:01:18: Max Q

The Falcon 9 rocket reaches Max Q, the point of maximum aerodynamic pressure.

T+0:02:42: MECO

The Falcon 9’s nine Merlin 1D engines shut down.
The Falcon 9’s nine Merlin 1D engines shut down.

T+0:02:46: Stage 1 Separation

The Falcon 9’s first stage separates from the second stage moments after MECO.

T+0:02:53: First Ignition of Second Stage

The second stage Merlin 1D vacuum engine ignites for an approximately 6-minute burn to put the rocket and SES 9 into a preliminary parking orbit.
The second stage Merlin 1D vacuum engine ignites for a nearly 6-minute burn to put the rocket and Intelsat 35e into a preliminary parking orbit.

T+0:03:39: 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.
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+0:08:37: SECO 1

The second stage of the Falcon 9 rocket shuts down after reaching a preliminary low-altitude orbit. The upper stage and SES 9 begin a coast phase scheduled to last more than 18 minutes before the second stage Merlin vacuum engine reignites.
The second stage of the Falcon 9 rocket shuts down after reaching a preliminary low-altitude orbit. The upper stage and Intelsat 35e begin a coast phase scheduled to last nearly 18 minutes before the second stage Merlin vacuum engine reignites.

T+0:26:18: Second Ignition of Second Stage

The Falcon 9's second stage Merlin engine restarts to propel the SES 9 communications satellite into a supersynchronous transfer orbit.
The Falcon 9’s second stage Merlin engine restarts to propel the Intelsat 35e communications satellite into a geostationary transfer orbit.

T+0:27:10 SECO 2

The Merlin engine shuts down after a short burn to put the SES 10 satellite in the proper orbit for deployment.
The Merlin engine shuts down after a short burn to put the Intelsat 35e satellite in the proper orbit for deployment.

T+0:32:01: Intelsat 35e Separation

The SES 9 satellite separates from the Falcon 9 rocket in an orbit with a predicted high point of about 39,300 kilometers (24,400 miles), a low point of 290 kilometers (180 miles) and an inclination of 28 degrees. Due to the decision to burn the second stage nearly to depletion, there is some slight uncertainty on the orbital parameters based on the exact performance of the launcher.
The Intelsat 35e satellite separates from the Falcon 9 rocket in a geostationary transfer orbit.

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