A SpaceX Falcon 9 rocket launched the second Tranche 1 Transport mission for the Space Development Agency (SDA) from California's Vandenberg Space Force Base on Oct. 15, 2025 at 7:06 p.m. EDT (2306 GMT; 4:06 p.m. local California time)
00:00T-minus 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, ignition, and liftoff of Falcon 9, go SpaceX, go SDA.
00:22Vehicle is pitching downrange.
00:24M.O.D. chamber pressures are nominal.
00:43At T-plus 30 seconds and counting, Falcon 9 has successfully lifted off from SLIC-4E at Vandenberg Space Force Base in California.
00:50We've got a great view of the rocket today.
00:52In case you are just joining us, this is the Space Development Agency's Tranche-1 mission, and we just had an on-time liftoff today.
00:59Power and telemetry nominal.
01:01Nominal liftoff today at 4.06 p.m. Pacific time.
01:05Coming up next, the vehicle will be passing through MAX-Q, which is the point in the mission profile where the vehicle experiences...
01:10Vehicle is supersonic.
01:11MAX-Q is the point in the mission profile where the vehicle experiences the greatest amount of aerodynamic pressure.
01:27MAX-Q.
01:29Falcon 9 has now passed through that period of MAX-Q.
01:31So coming up next, we'll have several events happening in quick succession, starting with MECO, then stage separation, then SES-1.
01:39Main engine cutoff, or MECO, is where all nine Merlin 1D engines shut down to slow the vehicle down in preparation for stage separation, which is where the first stage separates from the second stage.
01:49Following this, the MBAC engine on the second stage will light, which is called out as second engine start, or SES-1.
01:58This engine burn will last for several minutes and propel the second stage and the payload to orbit.
02:05In addition to these major events, the fairing halves will separate about 30 seconds after SES-1.
02:10And, as a reminder, we will not have any views of Falcon 9 second stage or the payload today at the request of our customer.
02:19So we should be coming up on MECO in 15 seconds here.
02:44MECO.
02:44Stage separation confirmed.
02:56MBAC start up.
03:00And there's that series of back-to-back callouts there, which, again, were MECO, stage separation, and SES-1.
03:05Coming up shortly, we should hear a callout for fairing separation.
03:08But as a reminder, we will not be showing it on screen today.
03:10Both payload fairing halves supporting today's mission are also flight-proven, with one half flying for its fourth time today and the other for its third.
03:20As a reminder, today we are delivering to orbit 21 satellites provided by Lockheed Martin.
03:24Faring separation confirmed.
03:37There's that confirmation of the fairing separation.
03:40As mentioned earlier, we will be attempting to retrieve these fairing halves again once they fall back to Earth with our West Coast recovery vessel, Go Beyond.
03:47Today is SpaceX's second Tranche-1 mission this year for the Space Development Agency.
03:54Our first Tranche-1 mission successfully launched on Wednesday, September 10th, at 7.12 a.m. Pacific time from Space Launch Complex 4 East, which is the same launch complex we use today at Vandenberg Space Force Base.
04:05The Space Development Agency's mesh network of optically connected satellites is primarily focused on tactical data delivery to warfighters, tracking and targeting for advanced missile threats, and beyond line-of-sight targeting for sensitive or mobile targets.
04:21We're currently just over 4 minutes and 10 seconds in today's mission.
04:26The next major milestone coming up in about 3 minutes will be the entry burn of the Falcon 9 booster as it continues on its journey towards our drone ship, Of Course I Still Love You, stationed in the Pacific.
04:37To start the entry burn, we will relight three of our M1D engines, which is similar to pumping the brakes to slow down the vehicle as it passes back into the Earth's atmosphere.
04:46We need to slow down the vehicle to reduce re-entry forces, which then helps us recover and reuse the first stage.
05:00If you're just joining us today, we are delivering to orbit 21 satellites provided by Lockheed Martin for the data transport layer of the proliferated warfighter space architecture.
05:09The data transport function delivers tactical data to warfighters wherever they are in the world.
05:14These 21 satellites are the second of 10 satellite planes that make up the first tranche of warfighter capability.
05:21The Tranche 1 constellation serves as the initial warfighting capability for the proliferated warfighter space architecture,
05:27and provides regional, persistent access to warfighters on land, at sea, and in the air for communications supporting advanced missile warning and missile tracking, and beyond line-of-sight targeting.
05:37When fully deployed, Tranche 1 will consist of 154 operational space vehicles, plus four missile defense demonstration space vehicles.
05:48Coming up next, we'll have the pre-entry burn, followed by the landing burn.
06:08At this point, we're about 30 seconds away from the beginning of the entry burn, and you should be able to see the graphics on the bottom of your screen light up as the engines do.
06:19Another 15 seconds here until that entry burn begins.
06:42Stage 1 FTS has saved.
06:47Nice call there.
06:47Stage 1 entry burn startup.
06:50And there's the call-out for the entry burn starting up on the Falcon 9 first stage.
06:54This burn is set to last about 25 seconds, and again, is slowing down the vehicle in preparation for its final burn and landing.
07:13Stage 1 entry burn shutdown.
07:14There's that call-out for entry burn shutdown, which marks the completion of the Falcon 9 first stage entry burn.
07:20Coming up next will be the first stage landing burn, which we'll start a little over a minute from now.
07:26The Merlins on the Falcon 9 first stage are optimized for sea level, and these achieve 190,000 pounds of thrust each during ascent and descent.
07:34At liftoff, Falcon's first stage has thrust greater than five 747 airplanes at full power.
07:40The single MBAC engine on the second stage has a much wider nozzle, and is optimized to operate in space, producing over 220,000 pounds of thrust in vacuum.
07:50Stage 1 transonic.
08:00Stage 2 terminal guidance.
08:02Stage 2 terminal guidance.
08:03Coming up next, we'll have the start of the landing burn of the first stage.
08:09The landing burn is the final burn of the Falcon 9 booster, and it's used to reduce the remaining speed of the vehicle for a gentle and precise landing on our drone ship, of course I still love you.
08:17Stage 2 FTS has saved.
08:19We should be hearing that call-up for the first stage landing burn in a few moments from now.
08:33Stage 1 landing burn.
08:35And there's that call-up.
08:36This is the final burn that this booster will see before landing.
08:39Landing light deploy.
08:54I'm back shut down.
08:59Stage 1 landing confirmed.
09:02Some awesome views there of the grid fins on our way down, and that marks another successful landing of our Falcon 9 rocket.
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