The fourth launch of the United Launch Alliance (ULA) Atlas V 551 rocket carrying the next batch of production satellites for Amazon Leo (formerly Project Kuiper), Leo 4, is planned for Dec. 15, 2025, pending range approval. The launch window opens at 3:52 a.m. EST. This launch continues a new chapter in the commercial launch industry as Amazon Leo partners with ULA to deliver the majority of its advanced satellites to low Earth orbit (LEO).
Atlas V to launch Amazon Leo 4ULA's Atlas V rocket will deliver another batch of satellites into low Earth orbit for Amazon Leo, the broadband constellation. Its mission is to provide fast, reliable internet to customers around the world, including those in unserved and underserved communities, using a network of more than 3,200 LEO satellites.Launch Date and Time: Monday, Dec. 15, 2025 with a window opening at 3:52 a.m. ESTGO Atlas! GO Centaur! GO Amazon Leo!
1941-EX-ST-2025 [Nov 17]QuoteLaunch vehicle communications for the launch of Atlas V vehicles with commercial satellites from Space Launch Complex 41 (LC-41) at Cape Canaveral Space Force Station.Operation Start Date: 12/13/2025Operation End Date: 03/13/2026I assume this is for a Kuiper Amazon LEO launch (KA-04), seeing as only one commercial Atlas V launch customer remains on the manifest.
Launch vehicle communications for the launch of Atlas V vehicles with commercial satellites from Space Launch Complex 41 (LC-41) at Cape Canaveral Space Force Station.Operation Start Date: 12/13/2025Operation End Date: 03/13/2026
Our next mission with @ulalaunch — and our first as Amazon Leo — is set for NET Mon. Dec. 15, with the launch window opening at 3:52 a.m. EST. Fast facts on LA-04 (Leo Atlas 4):➡️ Amazon’s fourth Atlas V launch➡️ Seventh mission of the year➡️ Adds 27 satellites to our constellation
Upcoming missionsLA-04: Amazon Leo’s next mission set for Monday, Dec. 15United Launch Alliance (ULA) is targeting Monday, Dec. 15 for our Leo Atlas 4 (LA-04) mission. Named LA-04 for Amazon’s fourth launch on an Atlas V rocket, the mission will send another 27 satellites to low Earth orbit, bringing the total number of Amazon Leo spacecraft launched to date to 180 satellites. The mission will launch from Space Launch Complex 41 at Cape Canaveral Space Force Station in Florida, with the launch window opening at 3:52 a.m. EST. The mission marks Amazon Leo’s fourth launch on Atlas V and the first as Amazon Leo.Mission No. 7Mission name: LA-04 (Leo Atlas 4)Launch vehicle: ULA Atlas V 551Launch date/time: The window opens on Monday, December 15, 2025, 3:52 a.m. EST.Number of satellites: 27Launch site: Space Launch Complex-41, Cape Canaveral Space Force Station
United Launch Alliance (ULA) hoists its Atlas V booster into the Vertical Integration Facility (VIF) adjacent to Space Launch Complex-41 at Cape Canaveral Space Force Station. The rocket will launch the Leo Atlas 4 (LA-4) mission for Amazon's broadband satellite constellation.
Will all the previous launch threads be retroactively renamed to LA/LV-X?
Launch processing efforts are underway to prepare our fourth Atlas V mission to deliver 27 advanced broadband satellites into space for the Amazon Leo constellation. The Amazon Leo 4 mission is targeting launch in the early morning hours of Dec. 15 from Cape Canaveral, Florida. Spectators from Florida to the Carolinas, New York City, New England and beyond will get a chance to see the rocket streaking into space, weather permitting in your area. Follow mission progress: http://bit.ly/av_leo4 Photos: https://flic.kr/s/aHBqjCBBpT
Launch Date and Time: Monday, Dec. 15, 2025 with a window opening at 3:35 a.m. EST
ULA technicians today transported the Amazon Leo Atlas 4 (LA-4) payload to the Vertical Integration Facility and hoisted the encapsulated satellites atop the Atlas V. This high-performance rocket, nicknamed "The Bruiser," will launch the satellites into space Dec. 15 to enhance broadband access and help connect the world. Launch info: http://bit.ly/av_leo4
Domi207 — 5:26 AMAn Atlas V fairing with 27 Kuiper satellites inside for the LA-04 mission has rolled out to SLC-41. The launch is currently scheduled to happen in 9 days
Launch Date and Window: Monday, Dec. 15, between 3:49 and 4:18 a.m. EST (0849-0918 UTC)
Amazon Leo@AmazonleoLA-04 update: Our encapsulated payload left Amazon’s processing facility on Friday for integration with Atlas V, with @ulalaunch targeting Dec. 15 to send another 27 Leo satellites into orbit.
ULA@ulalaunchAtlas V then reaches Mach 1 as it climbs through the atmosphere. About 96 seconds into ascent the solid rocket boosters complete their burn and separate.
ULA@ulalaunchWith the boosters jettisoned, the guidance system steers Atlas V toward its precise target in space. The 5-meter payload fairing continues to protect the Leo satellites during this phase of flight.
QuoteULA@ulalaunchOnce the rocket crosses the Karman line and enters space, the payload fairing is jettisoned. The first stage then completes its burn and separates from the vehicle.
ULA@ulalaunchOnce the rocket crosses the Karman line and enters space, the payload fairing is jettisoned. The first stage then completes its burn and separates from the vehicle.
ULA@ulalaunchCentaur begins second stage flight at less than seven percent of the rocket’s liftoff mass. Its RL10 engine ignites to place the mission into a circular low Earth orbit.
ULA@ulalaunchAfter engine shutdown, Centaur rotates to the correct orientation and releases @Amazonleo satellites, continuing their mission to provide reliable internet coverage around the world.
ULA@ulalaunchWatch live December 15Broadcast: 3:28 A.M EST
Primary Launch Day 15 DEC 0835Z-1026Z Backup Launch Day 16 DEC 0813Z-1004Z Backup Launch Day 17 DEC 0752Z-0943Z Backup Launch Day 18 DEC 0731Z-0922Z Backup Launch Day 19 DEC 0709Z-0900Z Backup Launch Day 20 DEC 0648Z-0839Z Backup Launch Day 21 DEC 0627Z-0818Z
Airspace EvaluationThe National Airspace System (NAS) hazard area evaluation examined five Aircraft Hazard Areas (AHAs) and the Special Use Airspace (SUA) associated with this launch. The first, AHA-A, extends from the launch site to 88nm northeastward. The second, AHA-B, extends from 108nm northeast of the launch site to 191nm northeast. The third, AHA-C, extends from 441nm northeast of the launch site to 641nm northeast.These three AHAs are within Miami, Jacksonville and New York ARTCCs. The forth, AHA-D, extends from 1789nm northeast of the launch site to 2100nm northeast and is located in the Gander FIR. A fifth AHA safeguarding the Stage 2 reentry is located west of Central America in the Mazatlan, Tahiti and Oakland FIRs.
Realistically, this is the last ULA launch of 2025?
Quote from: zubenelgenubi on 12/09/2025 11:20 pmRealistically, this is the last ULA launch of 2025?The shortest pad turnaround I found for SLC-41 since ULA acquired it in 2006 is 29 days, so yes.
Quote from: DanClemmensen on 12/09/2025 11:39 pmQuote from: zubenelgenubi on 12/09/2025 11:20 pmRealistically, this is the last ULA launch of 2025?The shortest pad turnaround I found for SLC-41 since ULA acquired it in 2006 is 29 days, so yes.I had a tiny bit of hope that they would be able to pull off a dual stack and back-to-back launch with Vulcan this year, but that's out of the question now. Bruno has all but confirmed a NET January on KV-01. I'm still holding out hope for a Vulcan stack to commence this month, though. Maybe even two...
