Launch timeline for Iridium’s seventh launch with SpaceX

July 25, 2018 Stephen Clark

Follow the key events of the Falcon 9 rocket’s ascent to orbit with the another set of 10 next-generation satellites for Iridium’s voice and data relay fleet.

The 229-foot-tall (70-meter) rocket will lift off Wednesday at 4:39 a.m. PDT (7:39 a.m. EDT; 1139 GMT) from Space Launch Complex 4-East at Vandenberg Air Force Base in California.

Data source: SpaceX

T-0:00:00: Liftoff

After the rocket's nine Merlin 1D engines pass an automated health check, the Falcon 9 is released from Space Launch Complex 4-East at Vandenberg Air Force Base, California.
After the rocket’s nine Merlin 1D engines pass an automated health check, the Falcon 9 is released from Space Launch Complex 4-East at Vandenberg Air Force Base, California.

T+0:01:12: Max-Q

The Falcon 9 rocket reaches Max Q, the point of maximum aerodynamic pressure.
The Falcon 9 rocket reaches Max Q, the point of maximum aerodynamic pressure. The first stage’s nine Merlin 1D engines produce about 1.7 million pounds of thrust.

T+0:02:24: MECO

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

T+0:02:27: Stage 1 Separation

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

T+0:02:29: Stage 2 Ignition

The second stage Merlin 1D vacuum engine ignites for an approximately 6-minute burn to inject the Jason 3 satellite into a parking orbit.
The second stage Merlin 1D vacuum engine ignites for an approximately 6-minute burn to inject the Iridium Next satellites into a parking orbit.

T+0:03:11: 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. The fairing halves will deploy parafoils for a controlled descent into the Pacific Ocean.

T+0:05:39: 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+0:07:17: Stage 1 Landing

The Falcon 9 rocket’s first stage booster touches down on SpaceX’s drone ship in the Pacific Ocean.

T+0:08:33: SECO 1

The Merlin 1D vacuum engine turns off after placing the Jason 3 satellite in temporary parking orbit, beginning at 46-minute coast in orbit.
The Merlin 1D vacuum engine turns off after placing the Iridium satellites in a temporary parking orbit, beginning at 43-minute coast in space.

T+0:51:28: Stage 2 Restart

The Falcon 9's second stage engine ignites again for a 12-second burn to circularize its orbit.
The Falcon 9’s second stage engine ignites again for a 9-second burn to circularize its orbit.

T+0:51:37: SECO 2

The Merlin 1D vacuum engine shuts down after reaching a target orbit with a high point of 857 miles (1,380 kilometers), a low point of 825 miles (1,328 kilometers) and an inclination of 66 degrees.
The Merlin 1D vacuum engine shuts down after reaching a target orbit about 388 miles (625 kilometers) high with an inclination of 86 degrees.

T+0:56:38: Begin Iridium Deployments

The 1,896-pound (860-kilogram) Iridium Next satellites begin deploying from their two-tier dispenser on the Falcon 9 rocket’s second stage, separating at intervals of approximately every 90 seconds.

T+1:11:38: End Iridium Deployments

The last of the 10 Iridium Next satellites will separate from the rocket.

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