Falcon 9 Block 5

Falcon 9 Block 5 is a partially reusable, human-rated, two-stage-to-orbit, medium-lift launch vehicle designed and manufactured in the United States by SpaceX. It is the fifth major version of the Falcon 9 family and the third version of the Falcon 9 Full Thrust.[8][9] It is powered by Merlin 1D engines burning rocket-grade kerosene (RP-1) and liquid oxygen (LOX).

The main changes from Block 3 (the original Falcon 9 Full Thrust) to Block 5 are higher-thrust engines and improvements to the landing legs along with numerous other small changes to streamline recovery and re-use of first-stage boosters and fairing halves and increase the production rate. Each Block 5 booster is designed to fly ten times with only minor maintenance between launches and potentially up to 100 times with periodic refurbishment, while fairing halves have been recovered and reflown countless times.

In 2018, Block 5 succeeded the transitional Block 4 version. The maiden flight of the Block 5 launched the satellite Bangabandhu-1 on May 11, 2018. The CRS-15 mission on June 29, 2018, was the last to be launched on a Block 4 rocket, completing the transition to an all-Block 5 fleet.[10][11]

Overview

The Block 5 design changes are principally driven by upgrades needed for NASA's Commercial Crew program and National Security Space Launch requirements.[12] They include performance upgrades, manufacturing improvements, and increase the margin for demanding customers.[13]

In April 2017, SpaceX CEO Elon Musk said that Block 5 will feature 7–8% more thrust by uprating the engines (from 176000 lbf to 190000 lbf per engine).[14] Block 5 includes an improved flight control system for an optimized angle of attack on the descent, lowering landing fuel requirements.

For reusability endurance:

For rapid reusability:

• expected to be able to fly ten times with only minor maintenance between launches[15] achieved in 2021[16]
• potentially fly up to 100 times with periodic refurbishment[15][17][18]
• a reusable heat shield protecting the engines and plumbing at the base of the rocket;
• more temperature-resistant cast and machined titanium grid fins;[19]
• a thermal-protection coating on the first stage to limit reentry heating damage, including a black thermal protection layer on the landing legs, raceway, and interstage;
• redesigned and requalified more robust and longer life valves;
• redesigned composite overwrapped pressure vessels (COPV 2.0) for helium, to avoid oxygen freezing inside the structure of the tanks that lead to rupture.

• reduced refurbishment between flights;[15]
• a set of retractable landing legs for rapid recovery and shipping.[20]
• the Octaweb[21] structure is bolted together instead of welded, reducing manufacturing time.[22]

Improvements

Since the debut of Block 5, SpaceX has continued to iterate on its design, manufacturing processes, and operational procedures.[23] Later Block 5 boosters are also easier to prepare for flight, so SpaceX "prefer to retire" older cores by assigning them to expendable missions when possible.[24]

A pressure relief valve was added to the grid fins’ hydraulic system following a stall that resulted in a landing failure in 2018.[25][26] Similarly, after a booster was damaged at sea in 2022, much of the fleet was upgraded with "self-leveling" landing legs. These legs help ensure the booster can be properly secured to the Octograbber, even in suboptimal sea states.[27]

To improve the rocket's performance, SpaceX has tweaked throttle settings and separation timings.[23][28]

Human rating

The NASA certification processes of the 2010s specified seven flights of any launch vehicle without major design changes before the vehicle would be NASA-certified for human spaceflight, and allowed to fly NASA astronauts.[29][30]

The Block 5 design launched astronauts for the first time on May 30, 2020, on a NASA-contracted flight, Crew Dragon Demo-2.[37] This was the first crewed orbital spaceflight launched from the United States since the final Space Shuttle mission in 2011, and the first ever operated by a commercial provider.[38]

Specifications

Specifications and characteristics are as follows:[39][40][41]

Gallery

See also

• List of Falcon 9 and Falcon Heavy launches
• List of Falcon 9 Block 5 first-stage boosters

External links

• Link to Falcon User's Guide, by SpaceX. Updated in January 2019 specifically for Block 5 upgrades.