Live coverage: Arianespace to launch its heaviest payload to date with Amazon Leo flight

Arianespace’s Ariane 64 rocket stands at the launch pad at Europe’s Spaceport in French Guiana ahead of the launch of the Leo Europe 03 mission for Amazon Leo. Image: Arianespace Arianespace is preparing to launch its largest and heaviest payload to date on a version of its Ariane 6 rocket that incorporates new solid rocket boosters. The mission is designated VA269 by Arianespace and Leo Europe 03 (LE-03) by Amazon. It will send 36 Amazon Leo broadband internet satellites into low Earth orbit. This is the third of 18 Ariane 6 flights booked by Amazon Leo to deploy its constellation and follows successful flights in February and April. “We have both institutional and commercial clients and our main and biggest client today is Amazon. And I must say, we are very proud to work together,” said David Cavaillolès, CEO of Arianespace, during a pre-launch press briefing. “For me, it’s much more than a contract. It’s really a partnership.” Liftoff from Europe’s Spaceport in French Guiana is scheduled during a window that opens at 8:53 a.m. Kourou time (7:53 a.m. EDT / 1153 UTC). Spaceflight Now will have live coverage beginning about 30 minutes prior to liftoff.  While all three of the Amazon Leo missions for Arianespace have used the Ariane 64 configuration of the rocket with four solid rocket boosters, the LE-03 mission will debut the upgraded version, called P160C. Compared to the predecessor P120C design, the P160C is a meter longer and holds about 156 tons of solid propellant. That’s about 14 more tons than the P120C boosters, allowing for a 10-15 percent increase in performance for the launcher. The P160C boosters can produce 3,800 kN of thrust each at liftoff compared to 3,700 kN of thrust from the P120C boosters. This iteration of the Ariane 64 can deliver 36 Amazon Leo satellites to orbit, four more than previously. Cavaillolès said described this upcoming launch as a big milestone for the company. “It’s important and we want to secure this milestone. This is our focus as of today, but of course, the story doesn’t stop there,” Cavaillolès said. “The more we launch, the better we know the launcher. We are already looking at further improvements. So we’ll do our best to keep increasing the performance of the launcher and thus the number of satellites we can carry for each launch.” For the first time, Ariane 64 will fly with four P160C boosters. +1 meter longer than P120C 156 tonnes of propellant pic.twitter.com/q5gdSWT274 — Arianespace (@Arianespace) June 4, 2026 Less than 2.5 minutes after liftoff, the four P160C boosters will separate from the Ariane 6 main stage, followed by fairing jettison less than a minute later. The first and second stages will separate nearly eight minutes into flight and the Vinci engine will begin the first of two, pre-deployment burns. The deployment sequence for the Amazon Leo satellites will begin nearly an hour-and-a-half into flight and conclude at about one hour and 51 minutes post-liftoff. The Vinci engine will then perform a de-orbit burn about two hours and 40 minutes after takeoff. “When this mission is complete, Arianespace will have launched 100 of our satellites to date. That’s three missions in less than five months, which is just fantastic,” said Steven Metayer, vice president of Production Operations at Amazon. “It’s just something we really count on to build that constellation out at rate across all providers.” Building a constellation Prior to Wednesday’s launch, Amazon has deployed 331 satellites on 12 missions by three different launch providers: Arianespace, SpaceX, and United Launch Alliance. Metayer said production of the satellites is ramping up and is exceeding the rate at which they are currently able to get them into orbit. He said Amazon is currently manufacturing “several satellites per day” at their facilities in the State of Washington. In Florida, he said they are able to receive satellites at their payload processing facility at NASA’s Kennedy Space Center and get them integrated into a dispenser in about a week. “We’re comfortable right now running ahead of launch. We know that when these heavy lift vehicles, such as the Ariane 64 and then you add the Vulcan and New Glenn to that, we know that we’ll have quite a consumption rate demand from launches,” Metayer said. “So we’re comfortable right now building ahead of where we need to be and to make sure we never ever run out of satellites.” Those two launchers, New Glenn and Vulcan, are both grounded for an undetermined amount of time. For ULA, it’s Vulcan rocket has been grounded due to a problem with one of its solid rocket boosters during the USSF-87 mission in February. The timeline for concluding its anomaly investigation isn’t publicly known, but Metayer said Amazon is anticipating being able to launch its first Leo Vulcan mission “sometime in Q3, the end of Q3.” ULA stacked its first Vulcan rock