The 3 and 4 configurations are based on the design of the classic separation of the aircraft body and the propulsion system. They didn’t consider a synergic approach between the propulsion system and the aircraft (body and wings) configuration. It is a must for the future VTOL dominant technologies to take into account that.
I think NASA's goal is to size these reference vehicles at a high-level first. Then, they may (or industry) will introduce more precision and much more sophistication to the sizing exercise.
The 3 and 4 configurations are based on the design of the classic separation of the aircraft body and the propulsion system. They didn’t consider a synergic approach between the propulsion system and the aircraft (body and wings) configuration. It is a must for the future VTOL dominant technologies to take into account that.
Thank you for your comment Liviu!
I think NASA's goal is to size these reference vehicles at a high-level first. Then, they may (or industry) will introduce more precision and much more sophistication to the sizing exercise.