Radian SSTO spaceplane concept

Ars Technica post by Eric Berger

Comment:

This looks like another stab at the VentureStar concept that NASA was working on in the late nineties, and was cancelled by the new, at the time, Bush Administration in 2001. Actually, it was called X-33, which was a suborbital test bed version of a Single Stage to Orbit spacecraft. (SSTO)

This article doesn't go into great detail about the technical specs of the thing. The project does appear to have some of the conceptual pedigree of it. The thing that grabs me the most about it is the SMALLNESS of the craft. I should add that it may not be all that small, but from what information that the article DID supply would suggest a small spacecraft indeed. For instance, it has 3 engines, and the engines may only have 200k of thrust. That would imply a mass less than 600k, or it cannot get to orbit. It will launch similar to a plane and land like a plane, which is slightly different from X-33 (VentureStar).

For comparisons, a Falcon 9 Full thrust version that has been operational for a while, masses out at liftoff at about 1.2 million pounds. It is my estimation that this vehicle could be about 1/3 of the liftoff mass of the Falcon 9. It won't have the same payload capacity. It won't carry all that many passengers. But it would be a serviceable vehicle for some types of missions. One thing that it has going for it is that it could land on a airport, and also take off of a runway. It may also resemble the Skylon concept over in Europe. However, it may need launch assist from a sled device. That may help with mass, and why it may be a smaller craft. A 747 masses out similar to this thing. The X-33 launched like the Shuttle and landed on a runway.

The article doesn't say that the engines will use aerospikes or not. Aerospikes could help with efficiency, but it is a cutting edge tech even these days. It might have been a bridge too far back in 2001. The thing that really cooked the VentureStar in 2001 were the issues with the leaking fuel tanks. That problem was solved, but they cancelled anyway.

The latest attempt at an SSTO will be privately funded, if it happens at all. Here's the link to Radian Aerospace .