Stratolaunch Systems plans to employ a family of four launch vehicles

All of them will blast their way to orbit after being dropped at altitude from a mother-ship plane — the largest aircraft ever built, with a wingspan of 385 feet (117 meters).
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• Pegasus: built by aerospace company Northrop Grumman. Pegasus will be able to haul payloads as heavy as 815 lbs. (370 kilograms)
• Medium Launch Vehicle (MLV): payload capacity of 7,500 lbs. (3,400 kg). 
• Medium Launch Vehicle - Heavy: payload 13,200 lbs. (6,000 kg).
• Space Plane: This fully reusable vehicle will be able to haul payloads up and bring them back down to Earth 

 Continue reading: https://www.stratolaunch.com/2018/08/20/stratolaunch-announces-new-launch-vehicles/


related:

https://www.space.com/41548-stratolaunch-rocket-family-space-plane-revealed.html


https://www.cnbc.com/video/2018/08/20/space-race-paul-allens-stratolaunch-mega-plane.html

https://www.wired.com/story/stratolaunch-airplane-burt-rutan-paul-allen/