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TBO Extension

What is Aircraft TBO and Why is it Important?

TBO for aircraft, also known as the time between overhauls or time before overhaul is the recommended time or cycle between engine overhauls and is important because it’s a major factor in determining how long your aircraft’s engine will last. Let’s take a closer look at what TBO is and how it affects your aircraft’s engine.

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    How is the TBO of An Aircraft Engine Determined?

    TBO is set by the engine manufacturer and is based on data collected from operating the new engine under various conditions and flying environments and then approved by the FAA. Manufacturers use a variety of factors to determine TBO, including materials research, flight testing, and field experience. Once an engine has been through its initial service life and the manufacturer has gathered enough data, they’ll settle on a TBO and submit it to the FAA for approval.

    After that point, the FAA conducts its own reviews every 5 years to make sure the TBO is still accurate. If they find that it needs to be revised, they’ll work with the manufacturer to update the TBO. However, if an engine manufacturer wants to increase its TBO without conducting any additional research or testing, the FAA will not approve the change.

    The majority of piston-powered aircraft engines have a TBO in the range of 1,800 to 2,400 hours. However, there are some high-performance engines that have a TBO as high as 3,600 hours. Meanwhile, turbine-powered engines usually have a TBO between 3,500 and 6,000 hours.

    Depending on the make and model of your aircraft’s engine, as well as the way you fly, your TBO could be anywhere from 3,000 to 6,000 hours. If you exceed your TBO, you run the risk of damaging your engine beyond repair. That’s why it’s important to keep track of your TBO and schedule regular maintenance accordingly.

    Can TBO be Extended?

    This is a question asked by many owners, and the short answer is in some cases, yes.

    The preferred path taken by most owners is to find a reputable TBO Extension program that can help to lengthen the time between engine overhauls by 2000 hours or even more in some circumstances for a fraction of the cost of a major engine overhaul.

    According to the FAA, you can keep operating your engine past TBO as long as it continues meeting mandatory service bulletins and airworthiness directives and are flying under Part 91 or part 135 operations. Your mechanic must also confirm that the engine meets the minimum qualifications for being considered airworthy during inspections.

    How to Extend Your Aircraft Engine's TBO

    You can either pay for a TBO Extension program, or you can possibly extend your engine’s TBO by following the manufacturer’s recommended maintenance schedule. 

    This schedule should be followed religiously in order to ensure that your engine is running at peak performance and is not being pushed beyond its limits.

    It is always important for an aircraft owner to consider the risk of catastrophic failure by flying past TBO simply to avoid the overhaul cost.

    What Is Time Since Major Overhaul? (SMOH)

    Time Since Major Overhaul (SMOH) refers to the amount of time that has passed since a major overhaul was performed on an engine or its components. A major overhaul is a comprehensive restoration of an engine or component, bringing it back to factory specifications.

    It’s important to note that SMOH and TBO are not interchangeable terms. TBO refers to the manufacturer’s recommended time between overhauls, while SMOH refers to the specific amount of time that has passed since an individual engine’s last major engine overhaul.

    Having a low SMOH can be advantageous when purchasing an aircraft, as it means that the engine or component has not been in use for very long and may still have a significant amount of time before it needs to be overhauled again.

    However, it’s not the only factor to consider when evaluating an engine or component’s condition, regular maintenance, and proper usage are also crucial in determining its overall health and longevity.

    The Importance of the Regular Maintenance of Aircraft Engines

    Regular maintenance is key to keeping your aircraft engine running for as long as possible. Not only will regular maintenance help extend the life of your engine, but it will also help ensure that your engine is running at peak performance.

    During a regular maintenance check, a qualified mechanic will inspect your engine for wear and tear and perform any necessary repairs or replacements. They will also change the oil and filter, check the fuel system for leaks, and inspect the exhaust system for blockages.

    Also, ensure you get a Hot Section Inspection or HSI. A host section inspection of an aircraft is when the turbine section is inspected, disassembled, and any necessary repairs or part replacements are completed. HSI’s should be performed at half of the recommended TBO interval for your engine.

    In addition to following the manufacturer’s specifications and maintenance schedule, there are a few other things you can do to help extend your engine’s TBO. These include:

    • Operating your engines within their approved power range
    • Avoiding prolonged operation at low power settings
    • Flying in moderate climates
    • Keeping your aircraft clean
    • Using good quality aviation fuel
    • Storing your aircraft properly when not in use

    Get more information on extending the life of your aircraft

    Monitoring TBO Is Essential

    The time between overhauls is an important factor to consider when purchasing an aircraft or maintaining an aircraft engine. By following the manufacturer’s recommended maintenance schedule and taking good care of your engines, you can help extend the TBO of your plane and keep it running great for years to come.

    If you have any questions about flying past TBO, getting a Hot Section Inspection for your plane, or if you are interested in knowing more about our TBO Extension program, please contact us today.

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