Multiple Rocket Types Deploy Amazon Leo Satellites in Series of Launches

A series of launches by United Launch Alliance (ULA) and Arianespace have deployed satellites for Amazon’s low Earth orbit broadband constellation, formerly known as Project Kuiper. The missions involved Atlas V and Ariane 6 rockets, with some flights setting payload records for their respective vehicles.

Launch Summary

A United Launch Alliance Atlas V rocket launched 29 Amazon Leo satellites on April 4 at 1:46 a.m. EDT from Cape Canaveral Space Force Station in Florida. The total payload weight was 18 tons, marking the heaviest payload ever carried by an Atlas V. All 29 satellites were successfully deployed.

A second Atlas V mission launched 29 additional Amazon Leo satellites on April 27 at 8:53 p.m. EDT from the same facility. This mission matched the 18-ton payload record set earlier in the month.

• The April 4 mission achieved its increased payload capacity through engineering collaboration between Amazon and ULA, involving a new, higher-performing version of the RL10C engine on the rocket’s Centaur upper stage.
• The April 27 mission set a new pad turnaround record for ULA of 23 days, 19 hours, and 6 minutes, surpassing the previous record of 26 days, 5 hours, and 19 minutes.
• For the April 27 launch, ULA implemented a compressed prelaunch schedule, rolling the rocket to the pad on the morning of launch.

An Ariane 6 rocket launched 32 Amazon Leo satellites on April 30 at 4:57 a.m. EDT from Europe’s Spaceport in Kourou, French Guiana. The mission deployed all satellites into low Earth orbit within two hours of liftoff. This was the seventh flight of Ariane 6 and the second with four P120C solid-propellant boosters.

A second Ariane 6 mission launched 36 Amazon Leo satellites on June 17 at 8:21 a.m. EDT from the same facility. This payload, weighing an estimated 20,820 kg (45,900 pounds), set a European record for the most mass delivered to space in a single launch, surpassing the previous record set by an Ariane 5 in 2013.

This was the first flight to use upgraded P160C solid-propellant boosters, which contain 14 tonnes more propellant per booster than the P120C version (156 tonnes total per booster) and are 14.5 meters tall.

The upgraded boosters increase payload capacity to low Earth orbit by more than two tons and improve performance by up to 15%, depending on the orbit. All satellites were deployed approximately one hour after liftoff.

Constellation Status

The Amazon Leo constellation is planned to consist of approximately 3,200 satellites in low Earth orbit. As of the June 17 launch, 100 satellites had been deployed.

Across all missions, Amazon has conducted 14 operational launches:

• Five on ULA Atlas V (as of the April 27 mission)
• Three on SpaceX Falcon 9
• Three on Arianespace Ariane 6 (as of the June 17 mission)
• One additional Falcon 9 or Ariane 6 launch (as of source counts)

The constellation will be built over more than 80 launches using multiple rocket types. Amazon has booked 18 Ariane 6 flights for the constellation.

Technical Details

• The Atlas V used for the April 27 mission stood 62.5 meters (205 feet) tall and launched on a north-easterly trajectory.
• The Ariane 6 VA268 mission used four P120C boosters, a long 20-meter fairing, and performed a third upper stage burn for safe deorbit.
• The P160C booster used for the June 17 mission was developed by Europropulsion under contract from ArianeGroup and Avio for ESA. The structure is made in Italy, the nozzle in France, and the igniter in Norway. Boosters are fueled and finalized at Europe’s Spaceport in French Guiana.
• Ariane 6 is developed by the European Space Agency (ESA) with an industrial network across 13 European countries. ArianeGroup is the prime contractor and design authority, Arianespace is the launch service provider, and CNES manages range operations.
• The P120C boosters are described by ESA as one of the most powerful one-piece motors in production.