Sunday, October 28, 2012

Flying Fast

One intriguing aspect a futuristic flying car is the promise of fast personal transportation. You will hover off your driveway and arrive at your destination hundreds of miles away within a few minutes. Lunch in New York and dinner in Los Angeles.

 To capitalize on this promise, the car must fly at a supersonic speeds. Supersonic flight involves shock waves (also called sonic booms) and this might not work so well for your neighbors. The following video shows a simulation of shock waves (generated using MultiElement Airfoils 5.0).

Shock waves/Sonic Boom Simulation

One way of reducing the effect of the sonic boom is to use the Busemann bi-plane concept. Of course, this arrangement of wings does not produce lift. However, they might be useful if integrated into the propulsion system or a cleverly designed shock wave deflectors for lifting surface.

 The figures below show MultiElement Airfoils calculations of the Busemann airfoil operating at on- and off-design conditions.

On-Design Analysis of Busemann bi-plane without external shock waves 
computed using MultiElement Airfoils.

Off-Design Analysis of Busemann bi-plane with external shock waves.

It is not too early to start your design of the next wave in personal transportation. Please visit to find out more about our software for analyzing multi-element airfoils in subsonic, transonic and supersonic flows.

I look forward to your comments and questions.

Thanks for reading.   Patrick.