Robinson R44 Raven II

The Robinson R44 is the world’s best-selling piston-powered helicopter, with over 6,000 delivered since it entered production in 1993. Designed by Frank Robinson — who previously created the even more popular R22 — the R44 expanded the successful formula to a four-seat cabin while retaining the simplicity and low operating cost that made Robinson Helicopter Company’s products the default choice for flight training programmes worldwide.

The R44 Raven II variant, introduced in 2002, replaced the earlier carburetted O-540 engine with the fuel-injected, turbocharged Lycoming IO-540-AE1A5. The fuel injection system eliminates carburetor icing, one of the most common causes of piston helicopter incidents, while the additional power improves hot-and-high performance significantly. The Raven II can takeoff from a 2,000-metre airfield in 38°C conditions with a full fuel load — a capability its predecessor struggled with.

Despite being designed primarily for training and private use, the R44 has found applications in aerial photography, powerline patrol, wildlife surveys, and law enforcement. Its low acquisition cost (approximately $390,000 new in 2024) and straightforward maintenance requirements make it accessible to operators who could not afford turbine helicopters. The common criticism — that the R44’s autorotation characteristics are less forgiving than larger helicopters — is acknowledged by Robinson, which mandates rigorous training requirements for R44 operators.