SpaceX Readies for First Flight of Upgraded Falcon 9 Block 5

The first Falcon 9 Block 5 booster heads for the launch pad at NASA’s Kennedy Space Center. (Credit: SpaceX)

Update: The launch was scrubbed for an undisclosed technical reason. SpaceX plans to try again on Friday at 4:14 p.m. EDT. Your local time may vary.

Elon Musk’s SpaceX will mark a major milestone for reusable rockets today with the launch of the upgraded Falcon 9 Block 5 booster.

The rocket is set to launch the Bangabandhu communications satellite for Bangladesh from NASA’s Kennedy Space Center in Florida. The launch window runs from  4:12-6:22 p.m. EDT (2012-2222 GMT). SpaceX will webcast the mission at

Falcon 9 Block 5 incorporates a number of changes designed to enable the recoverable first stage to launch 10 times or more “with very limited refurbishment,” SpaceX said. Previously recovered Falcon 9 first stages have been reused only one time apiece.

SpaceX eventually wants to be able to launch refurbished Falcon 9’s up to 100 times. The company also wants to be able to relaunch a first stage booster within 48 hours of it landing.

Some of the improvements to the Falcon 9 Block 5 include:

  • more powerful Merlin 1D engines;
  • improved flight controls for landing;
  • stronger heat shielding around the engines;
  • alterations to the engine turbo pumps to prevent micro-fractures;
  • modified composite overwrap pressure vessels (COPV) inside the fuel tank;
  • landing legs that can be retracted instead of being removed;
  • titanium grid fins on the first stage that can be reused many times; and,
  • a larger payload fairing with improvements to allow for recovery and reuse.

A key element of Falcon 9 Block 5 is launching crews to the International Space Station (ISS) aboard the Dragon 2 spacecraft for NASA. The space agency wants to see seven successful flights of this variant before astronauts fly aboard it.

In February, Musk said it would be “all hands on deck” for getting Dragon 2 to fly after the Falcon 9 Block 5 successfully debuts.

The Block 5 is set to be the last major upgrade of the Falcon 9. Musk has set his sights on the much larger Big Falcon Rocket (BFR), which is designed to carry crews to Mars.

Freezing the Falcon 9 design and reusing boosters many times will free up engineering talent for BFR.