Iowa automobile

[Cane Pole]

https://www.youtube.com/watch?v=Nk9Dl6RZxmQ

[skeetbum]

That's just some kinda cool!!

[PawPaw Gene]

There is a difference between rotary engines and radial engines. In rotary engines the block or cylinders rotate and not the crank. On the radial, the crank turns and the cylinders are stationary.

Here are a couple of links to the different kinds and other info.

The rotary engine and how it works with moving illustration showing the cylinders rotating around the crank which is stationary.
the Gnome rotary aero engine

The radial engine showing how the crank turns and moves the pistons in the stationary cylinders.
How a Radial Engine Works - Amazing "Cutaway in Motion" - YouTube

[Slab]

My bad. I did not know they had rotary plane engines. I thought we were confusing them with radials. Wowser, surprised those engines did not fly apart at those airplane speeds!

The Red Baron flew one: https://www.youtube.com/watch?v=C6xX0zSvp7w

[BoarBuster]

WOW that was something to see for sure, Thanks for posting it.

[crappiepappa]

On radial engines, there is a master rod that rotates via a shell bearing. This the only rod that actually rotates in the engine. All other rods, termed link rods, pivot on their own link pins. All single row radial engines have odd number cylinders. To keep the engine rotating, the engine fires every other cylinder. The camshaft really isn't a shaft at all but a ring. The ring has intake lobes and exhaust lobes each one opening and closing their respective valves. All but the most current radial engines (from the 40's to 60's ), are supercharged andrequire a prop reduction unit to keep prop tip speed below sub sonic. This is done with what's called a planetary gear, or cage with multiple smaller gears riding around a larger gear.

The crankshaft of a radial has counterweight cheeks that offset the balance and are near or at equal weight to the master rod weight assembly. An accessory drive shaft of various ratios drive magnetos, alternator/generators, fuel and hydraulic pumps.

Most radial engines used in today's world are electric start however, the Russians developed a radial engine in the 1940's that started on compressed air via an accessory driven air compressor mounted on the engine. The compressor is timed to the firing order of the engine. The starting procedure is to prime the engine, release the air from the air reserve tank and as the prop start to turn flip the ignition on. The compressor does double duty as an air pump to recharge the airtank mount within the airframe. This system requires 600 to 800 psi of air pressure to start the engine.

[crappiepappa]

CONTINUED

Each cylinder of all aircraft engines have 2 spark plugs per cylinder that fire at the same time. Both plugs are wired to the opposite mag for redundancy so that if you lose a mag or a plug, the cylinder will still fire but at half spark.

[Alboy79]

That's interesting.