Futuristic Biplane Design Eliminates Sonic Boom

Zothecula writes "A throwback to early 20th century aviation may hold the key to eliminating the sonic boom — at least according to researchers at MIT and Stanford University. Strongly reminiscent of biplanes still in use today, the researcher's concept supersonic aircraft introduces a second wing which, it is claimed, cancels the shockwaves generated by objects near or beyond the sound barrier."

Comments

Re:No sonic boom?

[element-o.p.]

And of course the shock-wave itself causes some major control issues as you pass through the barrier itself, at least as I understand it, as well as creating a huge amount of drag. That is a large reason they had so much trouble breaking the barrier in the first place: the planes would lose control as they passed through it and crash.

Yep. There were two big problems with control. The first was that as you move from subsonic to supersonic, the center of lift would move. The aircraft was balanced for controllability at subsonic flows, but when you passed from subsonic to supersonic, the aircraft became unstable and would either crash or break up. The second problem was that the control systems were easily manipulated by the pilot at subsonic speeds, but the shock wave created at the control surface hinge was too great for a human to overcome -- pilots literally weren't strong enough to push the control surfaces against the shock wave until engineers developed all-flying tail surfaces (stabilators rather than elevators). Overcoming drag was basically just a problem of developing a powerful enough engine.