Another design, says Perry, is the Karem Aerotrain. The Aerotrain’s fuselage looks very much like that of a conventional turboprop airliner you might see flying shorter routes, but its propellers tilt up or forward, just like the NGCTR.
“The Aerotrain is a 737-sized tiltrotor, which they claim will give passengers more of an airliner-style experience and capability, but will still be able to take off and land vertically.”
It’s a bold design, and one that may be too big to be feasible, but Perry adds that Karem has a good track record in creating aircraft that go against accepted practice – designer Abraham Karem is responsible for the jet-powered Predator drone widely used by the US military.
The Aerotrain was first unveiled in 2001 and has not yet flown; Perry says once the technology becomes advanced enough so that it can fly as efficiently as an airliner, it could become a viable alternative.
A close shave
There’s one big issue with these tiltrotors. The propeller blades needed to keep the aircraft in the air are huge. “They’re whirring very close to the aircraft’s fuselage,” says Perry. “What happens when it loses a blade in the middle of a flight?” Passengers might not feel very comfortable with massive propeller blades chopping through the air only a few feet away.