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The Rotary Engines Quiz
by Staff
Rotary engines have far fewer moving parts than conventional piston engines and run a lot smoother. See how much you know about these internal combustion engines by taking this quiz.

Who patented the first rotary engine?

  • Walter Hancock
  • Ferdinand Verbiest
  • Felix Millet

How many cylinders did Millet's engine have?

  • five
  • seven
  • eight

What year was the first rotary engine patented?

  • 1878
  • 1888
  • 1898

During which war were rotary engines used in many airplanes?

  • World War I
  • World War II
  • Korean War

Wankel rotary engines are also sometimes called what?

  • camless rotary engines
  • pistonless rotary engines
  • cylinderless rotary engines

What is the best trait of a Wankel rotary engine?

  • fantastic fuel efficiency
  • superb power-to-weight ratio
  • low oil requirements

Wankel engines are named for their inventor.

  • true
  • false

What major drawback did rotary engines present to novice pilots?

  • visibility issues
  • stability problems
  • spontaneous explosion

True or false: Wankel rotary engines use the same combustion cycle as four-stroke piston engines.

  • true
  • false

What was the primary advantage of the first rotary engines over radial engines?

  • better handling
  • better lubrication
  • better cooling

Which car brand is known for its occasional use of specific types of Wankel rotary engines?

  • Honda
  • Mazda
  • Nissan

What sort of cooling keeps rotary engines from overheating?

  • air cooling
  • nitrous cooling
  • liquid cooling

What phrase is used to describe a rotary engine's oil usage?

  • total loss
  • low ratio
  • low viscosity

Which British fighter plane used a rotary engine?

  • Spitfire
  • Sopwith Snipe
  • Armstrong Whitworth F.K.8

Where was the engine placed in the Megola, a 1920s German motorcycle?

  • front wheel
  • rear wheel
  • seat

Wankel engines can produce more power with less …

  • noise
  • vibration
  • oil checks

How the gyroscopic effect of the spinning engines affect fighter plane performance?

  • Right turns were slow and arduous.
  • Left turns were alarmingly fast.
  • It was pretty easy to keep the plane level.

True or false: Wankel rotary engines produce fewer emissions than piston engines.

  • true
  • false

The first rotary motors omitted which part altogether?

  • cylinders
  • crankshaft
  • flywheel

Which company made some of the most reliable rotary engines of the World War I era?

  • BMW
  • Gnome Engine Company
  • Hall-Scott Motor Co.

What does a radial engine have that a rotary engine does not?

  • spinning crankcase
  • rotating cylinders
  • rotating crankshaft

What was the approximate horsepower rating of the most powerful rotary engine from a World War I fighter plane?

  • 250 horsepower
  • 140 horsepower
  • 98 horsepower

When were the first Wankel rotary engines patented?

  • 1957
  • 1988
  • 1929

When did Felix Wankel finish his first working prototype?

  • 1957
  • 1944
  • 1938

What is one advantage of a Wankel rotary engine over a regular combustion engine?

  • shorter stroke duration
  • compact design
  • better sealing against the chamber ends

Why was the Mazda RX-8 ushered into retirement in 2012?

  • poor emissions performance
  • too many oil leaks
  • random engine failures

Why are Wankel rotary engines inefficient in terms of fuel usage?

  • The air cooling system means it needs a higher fuel-to-air ratio.
  • They have too much friction.
  • They work best at full throttle.

What was an unfortunate consequence for pilots who flew rotary engine fighters?

  • They were shot down because they were slow.
  • Oil from the engines splattered all over them.
  • Gasoline fires were a common occurrence.

With older Wankel engines, cold weather often caused which problem?

  • flooding
  • overacceleration
  • excessive vibration

The simple design of Wankel engines means they resist what?

  • crankshaft breakage
  • oil leaks
  • catastrophic failure