Starlink v2, Iridium and OneWeb satellites are set to fly the Falcon 9 missions on the same day

On the two main coasts of the United States, SpaceX is preparing to launch a number of low-Earth orbit communications satellites for three different networks, with launches scheduled to take place just over eight hours apart on the same day.

The first launch, Starlink Group 6-3, is scheduled to fly Friday, May 19 at 12:41 a.m. EST (04:41 UTC) from Space Launch Complex 40 (SLC-40) at Cape Canaveral Station of the Space Force in Florida. The launch time will be just under five days after the last flight from the same platform.

This will break the board turnaround time between launches that was slated between Amazonas Nexus and Starlink 5-4 launches earlier this year. The turnaround time then was five days, three hours, and 38 minutes, and if Starlink 6-3 were launched at any time during the Friday morning window, it would break that record.

Available launch times for Starlink 6-3 are from 12:00 to 4:20 AM EST (04:00 to 08:20 UTC) on Friday and 11:35 PM EST Friday night to 3:55 a.m. EST (03:35 to 07:55 UTC) on Saturday morning, with multiple launch opportunities during these periods.

Available T0 times for Friday morning are as follows: 12:41 AM EDT (04:41 UTC), 1:31 AM EDT (05:31 UTC), 2:19 AM EDT ( 06:19 UTC), and 3:09 a.m. EDT (07:09 UTC). The on-time launch will set the new SLC-40 turnaround record at four days, 23 hours, and 38 minutes.

If one of the other times is used, the new shift record will be five days, zero hours, 28 minutes, five days, one hour, 16 minutes, five days, two hours, and six minutes, respectively. Quick transitions between launches from the same pad are important to keeping up with SpaceX’s current launch cadence.

The 22 Starlink v2 Mini satellites will be launched on a southeast trajectory inclined 43 degrees to the equator. It will be inserted into an initial orbit of 344 km x 353 km. The satellites will be boosted to their operational 530-kilometer orbits in the coming weeks and months using onboard argon ion thrusters.

A view of the constellation of 21 Starlink v2 Mini satellites before they are embedded in their streamlined form prior to the previous launch. (credit: SpaceX)

Starlink 6-3 will use B1076 for its fifth flight, which will mark SpaceX’s 33rd Falcon 9 launch in 2023. Deficiency in Gravitas It is located at a depth of 636 km in the Atlantic Ocean. This kernel has previously flown CRS-26, OneWeb #16, Starlink 6-1 and Intelsat 40e/TEMPO missions.

This same booster is also scheduled to be converted into a Falcon Heavy side booster for use on the Echostar 24 (Jupiter 3) mission, scheduled for no later than next August. Falcon 9 boosters can be converted to Falcon Heavy side boosters, and vice versa as well.

Eight hours after Starlink 6-3’s scheduled launch, another Falcon 9 is scheduled to launch from Space Launch Complex 4E (SLC-4E) at Vandenberg Space Force Base in California. The windows available for this flight will be 6:04 to 7:12 AM PDT (13:04 to 14:12 UTC) on Friday and 6:00 to 7:07 AM PDT (13:00 to 14:07 UTC) on saturday.

B1063 will make its eleventh flight, the 31st Falcon 9 flight of the year, and SpaceX’s 33rd flight of 2023, with liftoff scheduled for 6:19 a.m. PDT (13:19 UTC). Flight – You are scheduled to land on the unmanned ship Of course I still love you Stationed in the Pacific Ocean – it will fly a polar path to the south, carrying five Iridium NEXT and 16 OneWeb satellites on board.

The five Iridium NEXT satellites will serve as replacements for some of the satellites SpaceX launched for the company between 2017 and 2019. The constellation consists of 66 operational satellites, nine in orbit, and six ground spares.

OneWeb’s second generation “JoeySat” was developed with assistance from the European Space Agency and the British Space Agency. (credit: ESA)

Although OneWeb’s initial operational constellation of 618 satellites is now in orbit, only 16 satellites will be flown on this mission. 15 of these satellites, of the same type as operating satellites, will become spares in orbit, while one of the satellites is a second-generation spacecraft, known as “JoeySat.”

The Iridium/OneWeb launch will be the second flight of the new shortened second-stage engine nozzle. The shorter nozzle, designed to reduce costs and increase launch cadence, made its debut at the Transporter-7 launch in April. The shortened nozzle slightly reduces performance, so it will only be used on missions that don’t need the Falcon 9’s full performance capability.

For this flight, the total payload mass is 6,600 kg, compared to 17,600 kg for the Starlink 6-3 launch. The Iridium Next satellites will be placed in an initial 615 km circular orbit inclined 86.4 degrees to the equator, while the OneWeb satellites will use a 1,200 km circular orbit inclined 87.9 degrees to the equator.

The Iridium satellites will be flown up to 625 km to the exit, and one of them will move into its operational orbit at an altitude of 760 km. The other four satellites will be located in different orbital planes at an altitude of 625 km.

Weather is a control element for the Starlink 6-3 launch. The 45th Weather Squadron’s latest forecast shows a 60 percent chance of a launch criteria violation due to weather at the beginning of the available window, and drops to a 40 percent chance of a violation at the end of the window.

The main concerns for the May 19 window are anvil bases, debris and cumulonimbus clouds, while the outlook looks better for the backup window 24 hours later.

For a 24-hour delay, there is a 40 percent chance of a violation at the beginning of the window and a 30 percent chance at the end of the window. The remaining concerns for the backup window are cumulus cloud bases and the anvil.

Launch Starlink 6-3 Weather Forecast. (credit: USSF)

There’s no official forecast yet for Vandenberg’s Iridium NEXT/OneWeb launch, but a local forecast shows the usual fog cover in the area for the morning hours. Fog is not usually a limitation at all for the Falcon 9.

The two launches are scheduled to be followed by a crewed Axiom-2 spaceflight from Launch Complex 39A at Kennedy Space Center the following week as SpaceX attempts to fly up to 100 orbital missions this year.

(TOP PHOTO: Falcon 9 gears up on SLC-4E ahead of a previous mission from Vandenberg. Credit: Jack Beyer for NSF)