This document discusses piston engines and jet engines used as aircraft powerplants. While piston engines were initially more efficient than early jet engines, jet engines have largely replaced piston engines in both military and civilian aviation due to various design and performance factors. These factors that determine the suitability of an engine for aircraft include payload, size, cost, maintenance requirements, materials used, engine cycle, aircraft speed, control, power-to-weight ratio, flight envelope, efficiency, fuel consumption, endurance, vibration, and noise levels.

1. INTRODUCTION PISTON & JET ENGINES AS AIRCRAFT POWERPLANT

2. PISTON & JET ENGINES The last piston engines had better efficiency than the first jet engines used in aviation, yet jet engines have almost replaced piston engines as aircraft power plant not only in military aviation but also in civil aviation.

3. PISTON & JET ENGINES The piston engines and the jet engines used in aviation vastly differ in various constructional aspects. D esign / performance factors decide the suitability of a particular type of aero-engine for selection in aircraft as the power plant.

4. PISTON & JET ENGINES Design criteria pay load frontal area and size of aircraft cost & speed of production ease of maintenance metallurgical requirements working cycle aircraft speed operational flexibility landing / take-off run ease of control

5. PISTON & JET ENGINES Performance criteria power-weight ratio flight envelope thermal efficiency fuel consumption endurance of flight (range & duration) RPM engine vibration engine noise

6. ? Any Question