The power of the radial engine cannot be denied, especially when it is viewed within the historical context of flight. These engines were some of the first to be fitted in fighter planes and commercial aircraft, and their ability to deliver horsepower is also backed by the size and weight of the design. Getting the most out of a radial engine for in flight performance and greater safety can come down to both operational and maintenance procedures.
The Feeling Of The Engine
Many small aircraft pilots do prefer radial engines, because they offer a greater feeling of control and provide a visceral baseline for proper performance. This also means that pilots can coax greater power out of the engine through throttle use at takeoff. These engines also have a carburetor design that allows for maximum fuel to be pushed through the economizer valve, which also cools down the cylinders for better air flow. The result is that pressing full throttle at takeoff can also keep the radial engine going.
When in flight, the practice of not exceeding a 10 spread between manifold pressure and RPM is also important. This can reduce piston ring wear, but it can also prevent oil from venting with high crank-case pressure. During landing it can also be necessary to pay close attention to manifold pressure, as higher levels during the approach can result in sudden temperature changes in the engine that will result in cracked heads.
The Working Of The Engine
Along with good protocols for radial engine operation during flight, basic maintenance can also improve the performance of the aircraft. While scheduled MRO services and complete overhauls are also appropriate, pilots and owners can make a point of:
- Installing a new carburetor with a fresh complete overhaul – this ensures that fuel delivery and power stay high and consistent, and reduces the issues that can arise from clogged valves.
- Checking sparkplug function – electrical failures can be detrimental in aircraft operation, so testing sparkplugs regularly and replacing them as needed should be a standard procedure.
- Use proper fuel – higher fuel grades give greater engine performance because they have less impurities. This also means that higher grade fuel results in less debris collecting in the engine and impeding the movement of parts.
- Do visual inspections – issues such as cracked parts or poor performance can be detected by sight. Simply checking the engine on a regular basis can uncover whether greater MRO services are required.