SpaceX Falcon Heavy / ViaSat-3 Americas Launch

SpaceX plans to launch a Falcon Heavy rocket from Launch Complex 39A in Florida on 2023-04-30 in a 57 minute launch window starting at 23:29 UTC. The launch will place the ViaSat-3 Americas high bandwidth communications satellite directly in geostationary orbit, without requiring the satellite to raise its orbit using on-board propulsion. The launch will also orbit an Astranis MicroGEO satellite to provide communications services to Alaska and neighbouring regions and the GS-1 satellite for Gravity Space. Total payload mass is 6.7 tonnes.

This will be the sixth launch of a Falcon Heavy. The core stage, B1068, is making its first and last flight, while the two side boosters, B1052 and B1053, are making their eighth and third flights, respectively. B1052 has had an interesting career: it was originally built as a Falcon Heavy side booster and flew twice in 2019 on the second and third Falcon Heavy launches. In 2022, after 951 days sitting on the ground, it was converted to the regular Falcon 9 configuration and flew five times that year, launching three Starlink missions and two payloads for other customers. It was then converted back to the Falcon Heavy side booster configuration for this launch, 233 days after its previous flight as a Falcon 9. Side booster B1053 previously flew twice in 2019 on the second and third Falcon Heavy launches and is flying this time 1401 days after its last outing, a new record for longest time between flights.

Due to the payload mass and customer requirement of direct delivery to geostationary orbit, the Falcon Heavy core stage and both side boosters will be expended on this flight. This is the first fully expendable launch of Falcon Heavy—every previous launch has recovered the side boosters while some have expended the core stage. This mission profile requires the Falcon Heavy second stage to perform multiple burns with a long coast phase in between, so this second stage is equipped with the “mission extension kit” (MEK), which includes insulation to keep the RP-1 fuel from freezing during the coast, additional propellant pressurisation vessels, and more TEA -TEB hypergolic “starter fluid” to light the second stage engine multiple times. Falcon 9 and Heavy second stages with the MEK can be identified by the grey band of insulation on the RP-1 tank.

Here are the splashdown zones for the side boosters, ~770 km from the launch site, and core first stage, ~1880 km downrange. While no attempt will be made to recover the boosters, the recovery ship Doug will attempt to recover the payload fairings, which should splash down in the core booster impact zone, setting a new record for the distance of fairing recovery from the launch site.

Here is a pre-flight preview from Everyday Astronaut .


Most interesting. This brief tale is a reminder of why rocket science is referred to as “rocket science”. The ability to anticipate, discover, relate and account for the astounding number of interacting variables is truly inspiring.


The launch has been postponed one day, until 2023-04-27 at 23:29 UTC. The cause of the postponement was probably the weather, which had been forecast as only 50% favourable for today. The forecast for the 27th is 60% favourable. If the 27th doesn’t work out, there is a backup opportunity on the 28th at the same time.



There was a lightning strike near the launch pad before the postponement was announced.


The countdown was cut off at 59 seconds before launch for a reason not specified, and the launch scrubbed for today. Due to expected bad weather on the 29th, the launch has been rescheduled for Sunday, 2023-04-30 at the same time, 23:29 UTC.




SpaceX has released a video captured by a camera on board one of the payload fairing halves from this launch as it re-entered the atmosphere after being jettisoned by the second stage of the Falcon Heavy booster.

The original SpaceX video was posted only on Twitter, presumably because it is a part of the Musk Empire, and since Twitter videos cannot be embedded here, the above is a re-post by The fairing is moving from right to left in this video. Rotate your screen or head 90 degrees if you prefer to see it falling downward. To the right is the plasma tail of upper atmosphere gases ionised by compression as the fairing slams into the atmosphere.

This launch, which fully expended the Falcon Heavy, had a trajectory very unlike a typical Falcon 9 launch which generally separates the second stage at a velocity around 7500 km/hour (2 km/sec). In this flight, all of the fuel in the core and side boosters was used to accelerate to 17,078 km/hour at stage separation and the fairing was jettisoned at a velocity of 17,779 km/hour (4.9 m/sec). Thus, when the fairing halves encountered the atmosphere, they were travelling around 2.5 times as fast as usual for Falcon 9. Recall that kinetic energy is proportional to the square of the velocity, so the energy dissipated in re-entry at around Mach 15 was around six times higher than usual, so this was a “hot” re-entry in every sense of the word.

SpaceX did intend to recover the fairing halves, and the release of the video, which was obviously taken by a camera on a fairing half, indicates that they were successful in recovering at least that one.