Stratolaunch Talon-A

 Stratolaunch Systems

Now Stratolaunch is developing a reusable, rocket-powered, hypersonic flight vehicle called Talon-A that would be capable of flying at speeds of Mach 5�Mach 7. As of March 2020, the vehicle is planned to go into operation in 2022. The aircraft is 8.5 m (28 ft) in length, with a wingspan of 3.4 m (11.3 ft), and is intended to have a launch mass of approximately 2,700 kg (6,000 lb). As of November 2020, construction of the prototype was underway and portions of the fuselage were complete
Stratolaunch also has a concept in place, as of 2020, for a much larger Talon-Z that would be capable of carrying cargo payloads, and perhaps people as well, to orbit.

History

In August 2018, the company disclosed that it was planning a family of air-launch vehicles that would use the company�s giant airplane. The company said it was developing its own Medium Launch Vehicle (MLV) capable of placing up to 3,400 kilograms into low Earth orbit.
Stratolaunch revealed new details Sept. 27 (2018) about a rocket engine it is developing for use on future launch vehicles that will fly from a giant aircraft approaching its first flight.
The PGA engine � its name taken from the initials of Stratolaunch�s founder Paul G. Allen � will use liquid oxygen and liquid hydrogen propellants with fuel-rich staged combustion and a thrust of 200,000 pounds-force (890 kN).
Stratolaunch is currently working on the preburner for the PGA engine, the smaller of two combustion chambers in a staged combustion engine. In a fact sheet, Stratolaunch said it plans to perform a �full-scale� test of the preburner by the end of this year at NASA�s Stennis Space Center in Mississippi.
While this announcement has provided the most details to date on the company�s engine development plans, there�s been evidence for some time that the company planned to embark on developing its own engines. In 2017 the company hired a former SpaceX executive, Jeff Thornburg, as its vice president of propulsion. It also signed a Space Act Agreement last September to perform engine testing at Stennis.

Stratolaunch Systems developing a commercial air launch space access system. An enormous composite wing and fuselage sections of the 385-ft span carrier aircraft which will carry the Orbital ATK-built multi-stage booster to launch altitude. Provisional details of the booster itself have also been revealed by Orbital. Measuring around 128 ft long, the payload will be encased in a 16.4 ft diameter fairing. Gross lift off (or drop) weight is expected to be over 465,000 lb, with the air launch vehicle (Pegasus-II) able to deliver 13,500 lb to LEO, or 9,900 lb to a highly inclined (HIO) orbit, or 4,500 lb to GTO.
The Stratolaunch carrier aircraft will be able to take-off from airfields with a runway at least 12,100 ft in length and will be able to travel up to 1,200 nautical miles before releasing the Pegasus-II at an altitude of 30,000 ft. The system will be the largest aircraft ever built in terms of wingspan; with the first test flight of the carrier aircraft expected in 2015 from Scaled Composites' facilities in Mojave, California. Flight testing of the 6-engined carrier aircraft is expected to begin in 2016 with first launch of the ALV in 2018.
The first two stages of the Pegasus-II will have the same outside diameter as the Space Shuttle Solid Rocket Booster, but will be constructed using much lighter carbon-composite cases and contain a more energetic propellant mix. To provide guidance while in the atmosphere, the first stage will be equipped with two wings and a V-tail, both with control surfaces. Additionally, both the first and second stage motors will use a thrust vector control (TVC) system for attitude control in the thin upper atmosphere.
The third stage was originally intended to be a restartable cryogenic stage burning liquid hydrogen and liquid oxygen. Missions to LEO would have featured a 16 ft-diameter payload fairing and two Aerojet Rocketdyne RL-10C-1 engines, with a payload capacity of 13,500 lb. GTO missions would have used a 13 ft fairing and a single RL-10C-1 engine, with a payload capacity of approximately 4,500 lb. This vehicle would have had a gross weight of about 465,000 pounds.
 

In 2014, Stratolaunch announced that it was considering multiple launch vehicle options over a range of satellite sizes, and that some development work on the Orbital launch vehicle has been slowed down to focus on completion of the carrier aircraft.
In May 2015, it was announced that the Pegasus-II solid-fuel rocket was not achieving design economic goals and that Stratolaunch had contracted with the GenCorp division of Aerojet Rocketdyne to build the RL-10C-1 dual-motor liquid fuel engines for the launch vehicle.
In 2015 Stratolaunch Systems was placed under the supervision of Paul Allen's new company Vulcan Aerospace, a subsidiary of Vulcan, Inc. Vulcan Aerospace has its heritage in SpaceShipOne and oversees the Stratolaunch Systems project. Vulcan ended its contract with Orbital ATK in mid-2015 and indicated that a decision on a new rocket for the Stratolaunch Carrier Aircraft would be made in late 2015.