by jeff edwards
This past month I flew over to Piqua, Ohio to drop off my Lancair at Hartzell’s service center for a scheduled propeller overhaul. Hartzell recommends an overhaul every six calendar years. Unfortunately, we have seen more than one propeller depart a Lancair in the last several years, underlining the necessity of good propeller care. A couple of these events have been fatal, while others have resulted in a trip to the laundromat.
Review of Lancair accidents and incidents by LOBO’s Safety Working Group reveals an alarming number of propeller failures. In some cases the propeller to hub bolts were not properly torqued resulting in fatigue failure of the bolts. In other cases prop tips have departed causing an imbalance and severe vibration, necessitating an inflight shutdown of the engine. For more information about propeller maintenance see this excellent article at AOPA.
Many of our Lancairs are now over twenty years of age, with some of them still operating with the originally installed engine and propeller. While some of these machines don’t have a lot of operational time—many less than 1000 hours total time—they have decades of hangar time, or worse yet, a lot of outside storage time. The elements are hard on powerplant components. Internal corrosion is the nemesis of the propeller hub. The only way to properly inspect for corrosion is to disassemble the hub—in other words, overhaul. Reconditioning the blades including repainting them completes the process. The Hartzell team reinstalled the propeller and balanced the assembly for a smooth as silk operation. Check your aircraft logbooks to determine the age of your propeller, and know your propeller manufacturer’s recommendations for overhaul. If it is past the recommended overhaul time consider getting it overhauled at a qualified propeller shop. An ounce of prevention is worth a pound of cure.
For comments and questions contact Jeff via email at j.edwards [at] lancairowners.com