1. Crankshaft

3. • Changes reciprocating motion of pistons into
rotating motion to drive propeller
• Constructed of chrome-nickel-molybdenum-
steel
• May be one piece or as many as three separate
pieces
• The propeller mounts to the front of the
crankshaft using a spline, taper, or flange
• The crankshaft rotates within the crankcase and
is supported by main bearing journals
• Crankshaft throws or crankpins are off center
and account for the reciprocating motion of the
pistons

4. • same plane • cross plane
crank shaft

5. • Single-trow
• Two-trow
• Four-trow
• Six-trow

11. • The shaft is subjected to various forces but generally
needs to be analysed in two positions. Firstly, failure may
occur at the position of maximum bending; this may be
at the centre of the crank or at either end. In such a
condition the failure is due to bending and the pressure
in the cylinder is maximal. Second, the crank may fail due
to twisting, so the conrod needs to be checked for shear
at the position of maximal twisting. The pressure at this
position is the maximal pressure, but only a fraction of
maximal pressure

13. • CRANKSHAFT LOCATED AT AIRCRAFT ENGINE
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