Definition
A reciprocating engine in which two banks of cylinders are arranged at an angle to each other and share a common crankshaft, forming a V shape when viewed from the end.
Plain English
An engine where the cylinders are split into two rows that lean toward each other, meeting at the bottom to form a V.
Context Anchor
Seen in aircraft engine descriptions and maintenance material when the layout of the cylinders is being identified.
Derivation
Named after the shape the cylinder banks form. When you look at the engine from the front or rear, the two rows of cylinders make the letter V.
Why Pilots Care
Cylinder arrangement affects engine size, weight distribution, cooling method, and how the engine fits into the airframe. V-engines allow more cylinders in a narrower space than an in-line layout, which matters for aircraft design and maintenance access.
Analogy
Think of two rows of bottles leaning away from each other on a table. From the end of the table, the two rows would make a V shape.
Intuition Check
The V in V-engine does not mean an airspeed or V-speed. Here, V describes the physical shape of the engine’s cylinder arrangement.
Example Sentence 1
The classic Rolls-Royce Merlin used in the P-51 Mustang is a V-engine with twelve cylinders.
Example Sentence 2
Compared with a flat engine, the V-engine allowed a narrower cowling on the experimental aircraft.