FAA Powerplant Written Practice Test

What is the typical firing order on a 4 cylinder opposed aircraft engine?

1. From front to rear

2. Opposed cylinders from the rear to the front

3. Sequentially from left to right

4. By even and odd cylinders

The correct answer is: Opposed cylinders from the rear to the front

The typical firing order for a 4-cylinder opposed aircraft engine is from the rear to the front. This means that the firing sequence starts with the cylinders located towards the rear of the engine and progresses towards the front. This firing order is significant because it helps ensure balanced operation and smooth power delivery, reducing vibrations and enhancing the performance of the engine. In aircraft engines, the arrangement of cylinders and the order in which they fire are designed to achieve a smooth operation by evenly distributing power strokes. In a 4-cylinder opposed setup, the arrangement of the pistons and the way they interact with the crankshaft are critical. Firing from the rear to the front allows for the most efficient use of space and weight distribution, which are crucial factors in aircraft design and performance. Understanding this firing order is essential for maintenance and troubleshooting, as any deviations or issues with the order can lead to significant operational problems.