Aircraft Reciprocating Engines: DPR Aviation College

• This presentation provides an introduction to aircraft reciprocating engines at DPR Aviation College, taught by Mr. John Mark E. Dizon.
• The syllabus involves 7 hours of weekly instruction over 26 days, totaling 108 hours.
• Students are expected to attend class, participate actively, and submit assignments on time, with late work penalized by 10% per day, and work more than 5 days late not accepted.
• Academic integrity is required; dishonesty is not tolerated, and all submissions must be the student's original work with proper citations.
• For questions, the instructor is the primary contact, reachable via email during weekday working hours.

Subject Rules

• Students must check G-Class announcements, wear the correct uniform, and bring required PPE.
• Students must be on time and in the designated area, attending the attendance roll call.
• A task card must be requested for guidance on assigned work, roles assigned within the team, and tools audited before task execution.
• During the task, phone use is limited to the documenter, steps on the task card must be followed, and the work area must be kept clean.
• Scheduled breaks should be taken, hydration maintained, and any unwellness reported immediately.
• Completed work must be endorsed by the instructor, tools audited, and work details logged in both personal and aircraft logbooks.

Grading System

• Attendance and punctuality in laboratory sessions account for 15% of the grade.
• Adherence to safety protocols, PPE use, and tool handling in the maintenance lab counts for 10%.
• Hands-on skills assessment makes up 45% of the grade, including inspections, maintenance, troubleshooting, documentation, and lab participation.
• Midterm and final exams each contribute 15%, covering theoretical knowledge and practical skills.

Learning Objectives

• Understand reciprocating engines.
• Identify the common parts of reciprocating engines.
• Understand how reciprocating engines work.
• Identify the types of reciprocating engines.
• Practice using a micrometer and feeler gauge.

Reciprocating Engines

• The primary purpose of the reciprocating engine in an aircraft is to turn the propeller, which thrusts the aircraft forward.
• This engine type is an internal combustion engine commonly used in general aviation and smaller aircraft, burning a fuel and air mixture (avgas).

Common Parts

• The crankshaft converts the reciprocating motion of pistons into rotational motion to turn the propeller.
• Pistons move up and down within cylinders during combustion.
• Cylinders house the pistons and provide space for fuel-air mixture combustion.
• Spark plugs ignite the fuel-air mixture to start combustion.
• Valves control the intake of the fuel-air mixture and exhaust gases, including intake and exhaust valves.
• Connecting rods link pistons to the crankshaft.
• The camshaft controls valve timing, and carburetors/fuel injectors mix fuel with air before it enters the cylinders; modern engines often use fuel injection.
• The oil system lubricates parts to reduce wear, and the cooling system prevents overheating, typically through liquid or air cooling.

Types of Reciprocating Engines

• In-line
• V-type
• Opposed (horizontal or vertical)
• Radial

Basic Operation

• Intake: Air and fuel are drawn in and mixed in the carburetor or fuel injector system.
• Compression: Pistons compress the mixture inside the cylinders.
• Ignition: A spark plug ignites the compressed mixture, creating an explosion that forces the piston down.
• Power: The downward movement turns the crankshaft, powering the propeller.
• Exhaust: The piston moves upward, expelling exhaust gases to complete the cycle.
• This cycle repeats continuously.

Manufacturers

• Continental Aerospace Technologies
• Lycoming

Advantages

• Simplicity and reliability compared to turbine engines, making them easier to maintain and repair.
• They are more cost-effective, being generally more affordable than jet engines in terms of purchase price and maintenance.
• Better fuel efficiency compared to larger jet engines in smaller aircraft is characteristic.

Disadvantages

• Reciprocating engines have limited power compared to turbine engines, which can limit aircraft size and performance.
• These engines need higher maintenance, including components like spark plugs, cylinders, and valves.
• Altitude performance is lower; they lose performance at higher altitudes due to decreased air density.

Common Uses

• Light aircraft like the Piper Archer, Beechcraft B58 Baron, Piper J3 Cub, and Piper Aztec.
• Trainer aircraft like the Cessna 150, Piper Tomahawk, and Cessna 172
• Small commercial and cargo aircraft