that leaves 50 pounds for each 120 HP engine, which is about 1/3 the weight per horsepower of any internal combustion engine I am aware of

Then you haven't seen the twin rotor Norton rotary engines they are using. They powered motorbikes for quite a while, with an overall weight of 35 lbs for the race engines. I can't remember the specific BHP figures, but they were generating the same shaft outputs (and higher) than 1,000 cc bikes, whilst being officially rated as 600cc capacity. A damn good engine design.

that the engines are Wankel-type rotary engines. These engines have never been known for fuel economy

They are Norton rotaries. Norton specifically marketed the engine for lightweight, airborne applications, including drone engines and unmanned surveilance aircraft. They have excellent fuel economy and low weight - the road bikes they powered regularly returned around 34-40 mpg even when you thrashed the knackers off them. They only really got thirsty at low RPM, and the race bikes eventually sorted this out by good engine management and new fuelling strategies.

65 decibels at 500 feet. Yeah, right. With eight engines cranking out 960 horsepower and four eight-bladed ducted fans screaming for all they're worth...

Don't forget ducted fans are inherently quieter outside the duct - I think they are referring to the dBA (perceived loudness) levels on the ground.

So, I've heartlessly trashed submarines and aircars... what's next?

...and a good laugh was enjoyed by all. For someone who professes to be "no engineer", you do a pretty damn good job of analysis... Nice one, Doug!

PS. Oh, they may have one other minor problem that you don't mention here - Norton Motors (1974) Ltd. went belly up due to fraudulent financial dealing and bad marketing about 6 years ago - they don't make the engines any more and didn't license their manufacture to anyone....

PPS How did we get to be talking about rotary engines when we started out about AR screens?


One of the few remaining Mk1 owners... #00015