[axman88]

Ryan Kluftinger and the folks at Fortnine keep upping their game, in terms of production quality, writing, cinematography, music, ... their videos have it all.

https://www.youtube.com/watch?v=-3HBAvkc4a0

I never knew that the Wankel was designed by Nazis.  Or how many vehicle companies it has kneecapped.

[Hoiho]

Each release is an entertaining mini-doco.

[GlennF]

Mazda did OK with the rotaries despite buyer resistance but never really overcame the problems with expensive seals and seal wear.

***

There is also of course the OTHER type of rotary engine common in early aircraft where the entire engine rotates:

https://www.youtube.com/watch?v=TtMu8mrwM2k



***

Believe it or not, these aircraft style rotating engines where actually used in motorcycles, usually fitted inside the front wheel:

https://www.youtube.com/watch?v=ZghXM9xqCPA

https://youtu.be/DCt_G8j8Hfw?t=30

[AzCal Retred]

Well...Mazda didn't fare too badly after they figured out how to make good apex seals. It was used from 1978, finally ending in 2012 in the RX8 Sports car. There was a Sachs rotary engined trail bike too, noisy & hot but a lot of beans.

https://www.gearpatrol.com/cars/a34315143/mazda-rotary-engine-range-extender/
Mazda Confirms the Rotary Engine Will Return by 2022, but Not in a Sports Car

https://www.youtube.com/watch?v=G_7aDjfUN-8
DIRTBIKE WITH ROTARY ENGINE (Hercules Wankel 502 GS)

[Arschloch]

http://www.aixro.co.uk/product/aixro-xp-40-rotary-wankel-engine/

Power to weight makes the wankel interesting for ultralight aircraft.

[AzCal Retred]

It's a really compact power plant with few moving parts, looks like a natural fit for the EAA folks.

[cyrusb]

I think the Wankel began life as a supercharger, and was forced against it's will to be an engine.

[AzCal Retred]

Looks like maybe the engine idea (1920-ish?) segued into a supercharger (1956?) , then became a functional engine (1953-1957) as better materials became available. Pumping air & containing combustion gasses have different sealing hardware requirements. An engineer would have been aware of both possible used, depending on configuration as driver or driven. A lot like how an electric generator can also function as a motor, an idea commonly used to bring large synchronous condensers up to speed.

https://en.wikipedia.org/wiki/Wankel_engine
Concept:
The design was conceived by German engineer Felix Wankel. Wankel received his first patent for the engine in 1929. He began development in the early 1950s at NSU, completing a working prototype in 1957.[1] NSU subsequently licensed the design to companies around the world, that have continually made improvements.

https://www.autoweek.com/news/a2068406/1967-nsu-wankel-spider-rev-it/
NSU’s racing bikes enjoyed success after World War II, until the firm quit racing in the mid-1950s, at which point the company was known for popular mopeds like the Quickly. To boost moped marketing, NSU embarked on record-setting with the Quickly’s 50-cc engine, placing it in an enclosed motorcycle called the Flying Hammock. In 1956 it reached 122 mph at Bonneville, by virtue of its aerodynamics and a rotary supercharger inspired by Felix Wankel.

Wankel first conceived of a rotary engine in the 1920s, though differences with the Nazis and World War II impeded its development. But Wankel’s wartime work on rotary valves and seals would attract the attention of NSU racing director Walter Froede. By 1953 Froede had convinced NSU’s board to back research into Wankel’s engine, which yielded results with the first firing of a Wankel rotary in 1957.

[Arschloch]

It's a really compact power plant with few moving parts, looks like a natural fit for the EAA folks.

...a two stroke will fair better though, probably last longer too. However the amount of air time most paragliders see in a year the longlivity is probably a non issue.

[zimmemr]

Back in the day I had a Suzuki RE5 demo bike. I rode the thing for about 5000 miles. The bike had some glaring faults, it was loud, hot and thirsty. I think it got around 30 mpg, and would empty the oil injection tank, which Suzuki used to lube the apex seals in a few hundred miles. Worse it didn't make much power, two up it was a real dog and only slightly better solo. It was also a pain in the ass to service. That being said it handled well and was reliable, but overall wasn't a very good motorcycle.

That was my only experiance with rotary engines, and frankly it was more than enough.

[AzCal Retred]

...but it sure did have a nice rumpty-rump sound at idle! Rev it a bit and it made a B29-like drone. Suzuki told our dealership in Flagstaff that if a customer broke down, let them know and they'd send out a new machine. Too bad they didn't partner with Mazda and put a polish on it before releasing it. Suzuki's engine was a single rotor design, Mazda's are twin rotor I believe.

There was a group of Japanese businessmen that raced RX7's. They took a stock motor, changed the carburetion & exhaust & let it rev to 14,000 RPM and make about 275 HP. They started to clean up the track, as they simply didn't have to shift between corners, just let it spin. I think the "how big is the displacement" question eventually sidelined them, how did the three rotor faces compare to a piston motor? Three times as big, or just spinning three times as fast? Anyway, they got ran off after winning too much.

[zimmemr]

...but it sure did have a nice rumpty-rump sound at idle! Rev it a bit and it made a B29-like drone. Suzuki told our dealership in Flagstaff that if a customer broke down, let them know and they'd send out a new machine. Too bad they didn't partner with Mazda and put a polish on it before releasing it. Suzuki's engine was a single rotor design, Mazda's are twin rotor I believe.

There was a group of Japanese businessmen that raced RX7's. They took a stock motor, changed the carburetion & exhaust & let it rev to 14,000 RPM and make about 275 HP. They started to clean up the track, as they simply didn't have to shift between corners, just let it spin. I think the "how big is the displacement" question eventually sidelined them, how did the three rotor faces compare to a piston motor? Three times as big, or just spinning three times as fast? Anyway, they got ran off after winning too much.

It did hum...I've seen some of the race modified RX's go at Lime Rock, they ran like Jack the bear. 

[GlennF]

...but it sure did have a nice rumpty-rump sound at idle! Rev it a bit and it made a B29-like drone.

yes, well it may sound  a bit like a B29 but one has a set of four x 55 litre Wright R-3350-23 Duplex-Cyclone 18-cylinder air-cooled turbosupercharged radial engines at 2,200 hp each for a total of 220 litres, 72 cylinders and 8,800 HP - and the other has a Suzuki Wankel Rotary

R-3350 on a test stand ...

https://www.youtube.com/watch?v=VVvGfjKY18w

Another one, this time in a Connie ...

https://www.youtube.com/watch?v=IWj3oLjHEJY

[cyrusb]

yes, well it may sound  a bit like a B29 but one has a set of four x 55 litre Wright R-3350-23 Duplex-Cyclone 18-cylinder air-cooled turbosupercharged radial engines at 2,200 hp each for a total of 220 litres, 72 cylinders and 8,800 HP - and the other has a Suzuki Wankel Rotary

R-3350 on a test stand ...

https://www.youtube.com/watch?v=VVvGfjKY18w

Another one, this time in a Connie ...

https://www.youtube.com/watch?v=IWj3oLjHEJY

You got that right, or should I say Wright? I am partial to the Wasp 4360, truly amazing machines