USSF-44

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USSF-44
Type: multiple satellite start
(≥ 3 satellites)
Country: United StatesUnited States United States
Organization: US Space Force , SpaceX
Mission dates
Start date: Fall 2020 (planned)
Starting place: KSC LC-39A
Launcher: Falcon Heavy
Mission duration: > 5 hours

USSF-44 is a space mission of the United States Space Force and the space service provider SpaceX planned for fall 2020 . It includes the transport of at least three military and / or intelligence satellites into geosynchronous orbits . A Falcon Heavy will be used as a launch vehicle for the fourth time .

The mission was originally called AFSPC-44 and was renamed USSF-44 after the Space Force was established .

Start order and payloads

The order for the launch of the satellites was put out to tender in 2017 by the Air Force Space Command (AFSPC). In February 2019, SpaceX was awarded the contract for AFSPC-44 and two other launches, for a total of 297 million US dollars . The tender documents mention two payloads of up to 2 tons each, which are to be deployed in orbits at 35,093 km altitude and at an inclination of 5 ° . Such a direct-to-GEO transport requires more energy than the start in a conventional geostationary transfer orbit . Because of this demanding mission profile, the powerful Falcon Heavy rocket is used.

As only later became known, the microsatellite Tetra 1 is to be brought into a geosynchronous orbit with the same flight . The Space Force described the task of this satellite as “testing missions, tactics, techniques and procedures in and around geosynchronous orbit (s)”. The purpose of the two major main payloads remained secret. There could also be other unreleased USSF-44 payloads.

To transport the satellites, which are classified as particularly important and safety-critical, the rocket requires a special qualification , which the Space Force promised for July 2020.

Planned course of the mission

The launch is to take place from ramp 39A of the Kennedy Space Center in Florida , the only available launch site for the Falcon Heavy so far. The two side boosters of the rocket should land after their separation and be salvaged so that they can be reused. A landing of the main stage is not planned; this enables a higher transport capacity of the rocket because no fuel has to be kept for landing.

After the upper stage of the rocket has been swiveled into a geostationary transfer orbit , it will fly through space for more than five hours without propulsion until it reaches the apogee . Then its engine re-ignites and the orbit is circularized.

Individual evidence

  1. Twitter message from Stephen Clark, Spaceflight Now, June 26, 2019.
  2. a b c d e f g Stephen Clark: Falcon Heavy set for design validation milestone before late 2020 launch. In: Spaceflight Now. April 27, 2020, accessed April 28, 2020 .
  3. a b Evolved Expendable Launch Vehicle (EELV) Phase 1A Competitive Acquisition for L-85, L-87, Silentbarker, SBIRS GEO-5, and AFSPC-44; FA8811-18-R-0001, Attachment 5: Instructions to Offerors. (PDF) (No longer available online.) Air Force Space Command, Nov. 6, 2017, archived from the original on Feb. 20, 2019 ; Retrieved on May 3, 2019 (English, AFSPC-44 on pages 62-70; orbit heights are given here relative to the center of the earth).
  4. Stephen Clark: SpaceX, ULA win military contracts, Air Force renames EELV program. In: Spaceflight Now. March 7, 2019, accessed April 5, 2019 .
  5. Colin Clark: SMC Issues Final RFP For Five EELV Launches; SBIRS & 4 Classified Payloads. In: Breaking Defense. January 2, 2018, accessed May 4, 2019 .