Pilots and mechanics alike understand that when a propeller is out of balance, the best thing to do is dynamically balance it. A significantly out-of-balance prop can produce pronounced vibrations that are obvious to pilots, thus becoming a catalyst for getting the prop balanced. The benefits of having a balanced prop are well documented: smoother and safer flying, and lower maintenance costs.
Aircraft vibration is often insidious, slowly and imperceptibly increasing over time. It may not become obvious to pilots until it is severe, because engine mounts dampen what they feel, reducing the amount of vibration felt in the cockpit. However, persistent, low-level vibration can impact the instruments, engine and airframe. Because these low-level vibrations are harder for pilots to feel, they tend to go unresolved as they produce cumulative damage to critical components.
Wayne’s Aircraft Maintenance Services uses a Dynavibe GX3 dynamic balancer and vibration analyzer to help its clients detect and resolve vibration to prevent damage to instruments and other components. The vibration is most often the result of out-of-balance props. Their shop is located in hangar M7 at the Miami Executive Airport, and among their clients are three flight schools located at the airport. Cory Cappe, Director of Maintenance, uses the DynaVibe GX3 while maintaining aircraft for these schools and for his private customers. "Previous to balancing these propellers with DynaVibe, the flight schools were having an issues with instruments and mounts going bad, because of vibration, so we are [now] balancing their aircraft every six months." Since regular balancing of the flight school aircraft began, there have been fewer instrument failures reported.
Cory found that gyro instruments are particularly prone to damage from vibration, requiring costly repairs or replacement. Investing in regular dynamic prop balancing provides a far less costly measure of protection against instrument failure. Vibration can damage engines and airframes as well. Problems such as fatigue cracks or cracked exhaust systems are indicators that vibration may be compromising an airplane’s structural or mechanical integrity.
Cory’s private customers can also feel the difference when they have their aircraft dynamically balanced. A Bonanza came into the shop whose owner reported a bad vibration that he noticed during takeoff. The vibration was so pronounced that the pilot had concerns about flying the airplane. Using the DynaVibe GX3, the initial balancing run on this airplane revealed a vibration between .50 and .60 Inches Per Second (IPS). Vibration of this magnitude definitely indicates a need for balancing, and if left unresolved, can rapidly cause serious damage to the airframe, engine and instruments. Dynamically balancing this Bonanza with DynaVibe reduced the vibration down to just .03 IPS, and the pilot reported that he no longer felt the vibration.
The use of DynaVibe at Wayne’s Aircraft Maintenance Services is resulting in satisfied customers that experience smoother flying and fewer instrument failures. In the first year of usage, the company’s investment in DynaVibe is paying off.