Seattle-based Stratolaunch has taken the wraps off an expanded family of launch vehicles scheduled to enter service from 2020 onwards. The vehicles are designed to be air-launched from the company's giant six-engine carrier aircraft, which is currently in ground testing.

The updated launch offering from Stratolaunch includes the following vehicles (performance estimated for a 400km circular orbit at 28.5°):

• Pegasus: The existing Pegasus launcher, built by Northrop Grumman Innovation Systems (the former Orbital ATK), already boasts a track record of over 35 successful launches. Pegasus can carry a 370kg payload for a single or triple configuration. Integration and testing are currently ongoing, with a first flight on Stratolaunch set for 2020.

• Medium Launch Vehicle (MLV): a new medium-class air-launch vehicle (3,400kg payload) optimised for short satellite integration timelines, affordable launch and flexible launch profiles. The MLV is currently in development, with first flight set for 2022.

• Medium Launch Vehicle – Heavy: a three-core MLV variant with capability to deploy heavier payloads (6,000kg). This vehicle is in early development.

• Space Plane: A fully reusable space plane that enables advanced in-orbit capabilities and cargo return. Initial designs optimized for cargo launch, with a follow-on variant capable of transporting crew.

The aircraft is being built by Stratolaunch Systems Corp. in partnership with Scaled Composites, which is also part of Northrop Grumman.