MRO Special Industry Guide Vol I

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OVERHAUL 2.qxp_Finance 27/01/2021 10:12 Page 1

ENGINES CHRIS KJELGAARD has been an aviation journalist for 40 years, with a particular expertise on aircraft maintenance. He has served as editor of ten print and online titles and written extensively on many aspects of aviation. He also copy-edits most major documents published by a global aviation industry trade association.

Should You Overhaul, Replace, or Upgrade Your Engines? Engine overhauls are expensive, particularly for operators not enrolled in hourly maintenance plans and for engines undergoing their second or third overhaul. Chris Kjelgaard assesses the options available at that point…


eciding when the prospect of an engine overhaul is just too costly to be worthwhile can be a difficult decision. It is one that different owners and operators may see differently, depending on aircraft type, how the particular aircraft to which the engines in question are attached is operated, and even the owner/operator’s particular preference for retaining engine serial numbers it already owns and knows well. According to Andrew Robinson, Senior Vice President, Services & Customer Support for Rolls-Royce North America, overhauls of Rolls-Royce Tay 611-8 engines installed on 30-year-old Gulfstream IVs “are still occurring, but we’ve seen other aircraft [types] which are not as old for which it is deemed not as practical.” “Once an engine hits its second and third overhaul, the overhaul becomes a lot more expensive,” says Mike Saathoff, Director, Sales Operations and Engine Accessory Sales, Elliott Aviation. The cost of an engine overhaul goes up as the engine’s Life Limited Parts (LLPs) near, or reach, their cycle limits, at 18 Vol 25 Issue 2 2021 AVBUYER MAGAZINE

which point they must be replaced, according to Saathoff. Overhaul is also needed “if parts have major discrepancies and need to be replaced.” In either case, “the cost of doing an upgrade [to a new engine] becomes very close or almost equal to the cost of doing an overhaul,” he says.

What are the Options?

If the owners of run-out engines decide not to have them overhauled, they can explore a variety of options. For example, they can scrap the aircraft and engines, or try to sell them for any remaining value they have. In some cases, they can have the engines exchanged for new ones of the same model, or for used engines which have some service life left. For some aircraft types, usually turboprops such as Beechcraft King Air models rather than jets, owners can even replace the engines with powerplants of a different type or model to improve the aircraft’s range and fuel-burn performance. “It’s very common” for owners and operators to decide not to have an aircraft’s engines overhauled if they find that the cost of overhauling both powerplants exceeds the