Stopped Rotor Still Being Pursued

Boeing has been working on stopped rotor concept helos, where the rotor is stopped and functions as a wing at high speed, for years, despite the crashes of both of its prototype X-50 canard rotor wing (CRW) demonstrators.

Well, it looks like they folks at Boeing, Mesa^* have come up with a a less ambitious take on this concept that has not yet crashed.

It is significantly simplified, dispensing with the tip jet power for the main rotor, and using a conventional tail rotor, and the wings pivot, so as to reduce the amount that they reduce lift during takeoff.

Here we have:

Takeoff


Transition to low speed forward flight.


High speed compound helicopter mode.


Stopped rotor

^*Formerly McDonnell Douglas helicopters, formerly Hughes Helicopter. They make the Apache.