Page 412 - (DK) The Ultimate Visual Dictionary 2nd Ed.

SEA AND AIR

Modern piston MID WEST 75-HP TWO-STROKE,
THREE-CYLINDER ENGINE
Spark plug
aero-engines Coolant outlet

PISTON ENGINES today Cylinder head
are used mainly to power the
Exhaust
vast numbers of light aircraft Piston Cylinder barrel manifold
and microlights, as well as
crop-sprayers and crop-dusters,
small helicopters, and fire-
bombers (which dump water
MID WEST TWO-STROKE,
THREE-CYLNDER ENGINE on large fires). Virtually all
heavier aircraft are now powered by jet engines. Exhaust port Cylinder liner
Modern piston aero-engines work on the
Upper
same basic principles as the engine
crankcase
used by the Wright brothers in the Coolant
first powered flight in 1903. Reduction Pump drive belt pump
gearbox Driven gear Gearbox drive
However, today’s engines splines Connecting rod
are more sophisticated (con-rod)
Small
than earlier engines. end
Propeller
For example, modern drive Generator rotor
aero-engines may use a flange
two-stroke or a four-stroke
combustion cycle; they may
Big end
have from one to nine air- or Counterweight
Torsional Crankshaft
water-cooled cylinders, which vibration Sprag
may be arranged horizontally, damper clutch Ignition Stator
in-line, in V formation, or radially; and they trigger
housing
may drive the aircraft’s propeller either directly
or through a reduction gearbox. One of the more Gearbox mounting plate
unconventional types of modern aero-engine is Engine mounting plate
Lower
the rotary engine shown here, which has a trilobate crankcase
(three-sided) rotor spinning in a chamber
shaped like a fat figure-eight.
ROTOR AND HOUSINGS OF A MID WEST SINGLE-ROTOR ENGINE
Dowel
Propeller Coolant Inlet
bolt hole jacket tract
Propeller Stud
drive
flange
Stud hole
Roller

Eccentric- Stud hole
shaft
bearing
Propeller Dowel hole
shaft
rear Coolant Exhaust
bearing jacket Dowel Rotor chamber
tract
GEARBOX CASE FRONT HOUSING (FRONT END-PLATE) TROCHOID HOUSING

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