Launch timeline for SpaceX’s 20th space station resupply mission

SpaceX’s Falcon 9 rocket will go from Cape Canaveral to low Earth orbit in less than 10 minutes Friday night with a Dragon capsule heading for the International Space Station carrying more than 4,300 pounds of supplies and experiments.

Liftoff is set for 11:50 p.m. EST Friday (0450 GMT Saturday) from Cape Canaveral’s Complex 40 launch pad.

It will be the 82nd flight of a Falcon 9 rocket, and SpaceX’s fifth launch of the year. Working under contract to NASA, Saturday’s launch will be the 20th of least 26 SpaceX resupply missions to depart for the space station under two separate cargo transportation contracts.

The resupply mission, known as CRS-20 or SpaceX-20, will be the final flight of SpaceX’s first-generation Dragon cargo capsule. Future resupply flights to the station will be flown using the next-generation Dragon 2 vehicle, an automated, unpiloted capsule based on the new human-rated Crew Dragon spacecraft.

The illustrated timeline below outlines the launch sequence for the Falcon 9 flight with the Dragon spacecraft. It does not include times for the descent and landing of the first stage booster at Landing Zone 1 around 6 miles (9 kilometers) south of pad 40.

Three ignitions of the first stage engines after separation will steer the booster back toward Florida’s Space Coast from the northeast. Here are key times for the landing maneuvers:

  • T+plus 2 minutes, 35 seconds: First stage boost-back burn begins
  • T+plus 6 minutes, 32 seconds: First stage entry burn begins
  • T+plus 8 minutes, 17 seconds: First stage landing

The first two burns will be performed using three of the Falcon 9’s nine Merlin first stage engines. The final landing burn will occur using just the center engine.

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 40.

T+0:01:18: 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.

T+0:02:18: MECO

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

T+0:02:22: 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: Second Stage Ignition

The second stage Merlin 1D vacuum engine ignites for an approximately 7-minute burn to put the Dragon spacecraft into orbit.
The second stage Merlin 1D vacuum engine ignites for an approximately six-minute burn to put the Dragon spacecraft into orbit.

T+0:08:35: SECO

The second stage of the Falcon 9 rocket shuts down after reaching a target orbit with a low point of approximately 124 miles (200 kilometers), a high point of approximately 223 miles (360 kilometers) and an inclination of 51.6 degrees. The second stage will reignite for a de-orbit burn soon after deploying the Dragon spacecraft, aiming for a destructive re-entry over the Southern Ocean south of Australia.
The second stage of the Falcon 9 rocket shuts down after reaching a elliptical target orbit at an inclination of 51.6 degrees. The second stage will later reignite for a de-orbit burn, falling back into the atmosphere for a destructive re-entry.

T+0:09:35: Dragon Separation

The Dragon spacecraft separates from the Falcon 9 rocket's second stage.
The Dragon spacecraft separates from the Falcon 9 rocket’s second stage.

T+0:12:02: Solar Arrays Deployed

The Dragon spacecraft's two solar array wings extend one-at-a-time to a span of 54 feet (16.5 meters).
The Dragon spacecraft’s two solar array wings extend one-at-a-time to a span of 54 feet (16.5 meters).

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