Toroidal propeller

Very good innovation but what about variable pitch adjustment?

Does make more sense for boats, better efficiency at cruise RPM.
Problem I had in my boat was staying on plane at RPM that would not beat me to death from 3' waves in the Gulf Stream.
First world problems! lol

GallopingGhostler wrote:...........Due to size and complex shape, discussions focused on marine applications because props in general are smaller due to water density. ...............

I've been following this, too.  Apparently, the improvements in efficiency, fuel economy and noise reduction are true (I read it on the Internet, so it has to be, right?)

In any event, they are in production for marine applications.  Here's a link:  Sharrow Marine

It will be interesting to see how this plays out for our hobby.

I know that Bob, a friend in Hawaii would enjoy this new propeller technology. Back in the 1970's, he had a 16.5 foot Fiberform boat, would do trolling off the coasts of the island, Oahu. Went with him a couple times trolling, would burn easily 8 to 14 gallons of fuel with his 2 stroke outboard trolling 4 to 6 hours. Fuel in Hawaii has always been expensive, may be a dollar or more over California prices.

One time we were trolling off the beaches of Kailua on the windward (east) side of the island. Yeppers, I remember those 8 to 12 foot swells about may be 8 to 12 miles off the coast. You'd go between, only see walls of water, then hit the crest of the swell, looking straight down 8 to 12 feet, that was spooky. Bob would back off the throttle so we don't nose dive. The Maui Channel is very rough going, and we were on a "calm" day. That time we didn't get much.

Got somewhere a photo of where we caught a 140 lb. (63.5 kg) yellow fin tuna about 8 miles off the coast of Makaha Beach, where the international surfing championships are held. Then we went another 4 miles out, and caught a 240 lb. (109 kg.) yellow fin. Bob was able to pay for his fuel now. His dad owned a small grocery store in Kaimuki District (part of Honolulu), used his meat cutting equipment to butcher and wrap. About half the weight is usable meat. (Rest is skin, fins, bone and guts). Just needed to tell one of the ladies at church of his catch. She had all the women shortly after banging at his door to buy fish.

Hi All,

Looks hard to flip start to me,
Good glow,
A good prime,
Might be possible.
3in dia for a .049?
Waiting,
Take care,
Have fun,
Dave

Seems kind of louder in the one drone video, but maybe safer if you touch your hand on the tip. Maybe APC will make them. F2A speed plane may go over 200 mph at 40,000 rpm???!!!