Atlas V Leo 4 Turns the Page
From Space Launch Complex 41 at Cape Canaveral Space Force Station, Florida, a United Launch Alliance Atlas V leapt into the sky at 3:28 AM Eastern Time the morning of December 16th. With 27 satellites for Amazon’s Leo constellation aboard, the flight was the first in the home stretch for Atlas’ storied launch manifest as it pushes the internet constellation towards completion.
Atlas V flew Tuesday morning in its ubiquitous 551 launch configuration, sporting a 5.4-meter diameter payload fairing, 5 solid rocket boosters, and a single RL10 engine on the Centaur upper stage. This exact configuration is one of just two that will fill out the rest of the rocket’s manifest, down to the payload of 27 satellites arranged in rings on the payload adapter.
Amazon Leo, formerly Project Kuiper, is in full swing building out its network of over 3,000 internet satellites, mirroring the megaconstellation model pioneered by SpaceX’s Starlink. While Leo’s network uses fewer satellites, it still has a long way to go to meet its initial capability of over 500. The remaining four Atlas V Leo missions, designated LA-05 through LA-08, are all set to fly next year. At the same time, the constellation will abruptly diversify onto a variety of other launch vehicles, including 38 flights aboard ULA’s Vulcan, 18 flights on Ariane 6, and 12 flights on Blue Origin’s New Glenn.
Of Atlas V’s handful of remaining flights, four will appear identical to this one. The rest will use the N22 configuration—no fairing, 2 boosters, and 2 RL10s—to send Boeing’s Starliner spacecraft to the International Space Station. The exact number that will fly, however, is unclear; Starliner’s flight record is marred by a string of mishaps, and its future has frequently been called into question. The widely-publicized incident during its Crew Flight Test in 2024 ultimately led NASA and Boeing to modify their contract, turning the upcoming Starliner-1 mission into an uncrewed cargo flight, and reducing the total order from six missions to four. NASA reserves the option to procure two additional missions, and the final two Atlas rockets are reserved for this purpose, but whether they will fly as originally envisioned is an open question.
