What is the approximate piston displacement of a four-cylinder aircraft engine with a cylinder bore of 3.78 inches and a depth of 8.5 inches with a piston measuring 4.0 inches from the bottom?

To determine the approximate piston displacement of a four-cylinder aircraft engine, you need to calculate the displacement of a single cylinder first and then multiply that by the number of cylinders, which is four in this case.

The formula for the volume of a cylinder is:

[ V = \pi \times \left( \frac{d}{2} \right)^2 \times h ]

Where:

• ( V ) is the volume,

• ( d ) is the bore (diameter) of the cylinder,

• ( h ) is the stroke (depth) of the piston.

For this engine:

• The bore ( d = 3.78 ) inches,

• The piston stroke (depth) ( h ) is 8.5 inches.

First, calculate the radius by dividing the bore by 2:

[ \text{Radius} = \frac{3.78}{2} = 1.89 \text{ inches} ]

Now, substitute the values into the cylinder volume formula:

[ V = \pi \times (1.89)^2 \times 8.5 ]

Calculating ( (1.89)^2 ):

[ (1.89)^2 \approx 3