Damaged Propeller: Is It Time to Replace or Repair?
Propellers are an integral part of an aircraft's performance and safety. They are also one of the components most commonly exposed to environmental stressors. Although these elements are explicitly designed to withstand most occurrences, there will inevitably be a situation where a propeller is damaged, leaving the operator to ask, "Should I replace or repair my propeller?" This is an important question since propeller replacements can be costly, and not replacing a faulty propeller is a serious safety threat. In this blog, we will discuss the nuances associated with deciding whether a propeller needs to be repaired or replaced.
Modern propellers may be made of wood, aluminum alloys, composite materials, and rarely, other metals. Wood is the oldest material on this list and is hardly ever encountered besides in restoration aircraft. Although wood propellers were designed with longevity in mind, they are the most prone to warping and degradation. Like many other aerospace components, aluminum alloys began to predominate the propeller market due to its lightweight, strong, and corrosion-resistant nature. Aluminum is still found on the majority of aircraft today, although that is changing quickly due to the introduction of composite blades, which offer even lighter weight and less vibration.
With a better understanding of the various materials that may be used to manufacture propellers, it is now important to discuss some of the issues that may arise. The leading cause of propeller grounding is corrosion, since they are so frequently exposed to the environment and corrosive materials. Corrosion may be external, occurring on the blades, or internal, damaging more concealed components. If regular inspection and overhaul timetables are being followed, corrosion should never reach the level that requires replacement. Should only one part of the propeller assembly be damaged by corrosive elements, replacing that component alone typically suffices to restore airworthiness.
The FAA uses the phrase "physical damage" to encompass a diverse list of insults, ranging from very minor to catastrophic. Blade misalignment may be caused by a number of reasons, but all set the propellers up for a hazardous situation. Erosion occurs when small solids such as sand or dirt repeatedly strike the blades. When erosion ensues, it decreases the blade's corrosion resistance, which can lead to the aforementioned problems. Cracks are the most severe and can manifest anywhere in the propeller. This insidious damage pattern can quickly propagate and cause catastrophic failure. As such, recognition of cracks should shortly be followed by immediate removal and inspection of affected parts.
When the discussion of lightning strikes comes up in aviation, most immediately think of electronic and passenger safety. In that domain, massive strides in engineering have been made to ensure both sensitive electronics and commuters are unaffected. However, external components such as propellers are still vulnerable to the damaging effects of lightning. Particularly, lightning strikes tend to compromise the strength of the blade while also introducing unwanted magnetism.
In any case, repairing propeller components is always cheaper, faster, and more environmentally friendly. However, there are certain circumstances when replacement should be considered immediately. First, if the propeller has reached or is nearing its operational lifespan, it would be prudent for the operator to elect total replacement. Additionally, any damage that may lead to catastrophic failure should be treated with immediate replacement of all parts affected. One might also consider the general benefits of replacing propeller components with newer versions, particularly those with aluminum blades.
Whether you decide to repair individual parts through a mechanic or elect to replace and upgrade whole units, it is critical to obtain high-quality components from a reputable distributor. At AOG Purchasing, we can help you meet all of your aerospace part requirements with ease. Owned and operated by ASAP Semiconductor, we deliver access to an unparalleled inventory of over 2 billion ready-to-purchase components for the civil and defense aviation industries. Our team members work around the clock to provide customers with rapid quotes, answer questions, and support pressing matters such as AOG requirements. Explore our website today and get started on the purchasing process at any time using our Instant RFQ service.
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