Engine life is given by the manufacturer and differs among engine types; commercial wide-body powerplants normally work for 25-30 years, while regional-jet engines are retired after 15-20 years or 40,000-60,000 flight cycles, and fighter powerplants accumulate only 3,000-6,000 flight hours.
Because plane engines have to work in harsh conditions - high speed, high temperature, variable altitude - they do not last the aircraft's entire lifespan. Instead, over the course of the plane's life the engine is generally rebuilt two to three times before removal, with each remanufacture recovering part of its designed 5-8,000-hour active life.
Whether the limit is expressed in flight hours or flight cycles, proper operation and maintenance remain pivotal, since aircraft life spans depend on a range of factors and the airframe-and-engine lifecycle is limited to a certain number of flight cycles or hours.
Expert behind this article
Jim Goodrich
Jim Goodrich is a pilot, aviation expert and founder of Tsunami Air.
How long does an airplane engine last?
The hours an airplane engine can last varies based on the type of engine. Airline engines, for example the Rolls Royce Trent series, usually have TBOs of over 15,000 hours, and the average number of hours before the first overhaul for modern widebody engines is 20,000 flight hours. The average number of cycles for the first subsequent maintenance visit is reduced to 8,000, and for the second to 4,000.
Long-range widebody jets can theoretically last several decades with 25,000-45,000 flight cycles. Short-range narrowbody jets can last almost 35 years with nearly 50,000 flight cycles. A short-range Boeing 747 can last up to 135,000 flight hours, and a 400 Domestic Boeing 747 can last up to 165,000 flight hours. Turboprops can have a lifespan of 20-30 years with proper maintenance, and the composite-structured Boeing 787 Dreamliner can endure 44,000 flight cycles.
Airliners typically acquire 3-4 sets of engines during their lifetime because an engine is generally rebuilt two to three times before being removed from service over the course of the plane's life. The record for maximum time for an engine on wing is well over 40,000 hours.
How is aircraft engine life measured in hours and cycles?
Aircraft engine life is measured through two meters: engine flight hours (EFH) and engine flight cycles (EFC). Flight hours are familiar time units, while a flight cycle is one take-off and subsequent landing, equivalent to an engine start-up, heating to operating temperatures, and shut-off. Modern engines record every cycle while older engines do not. Airlines and operators track EFH and EFC to predict when the engine requires a maintenance, repair, and overhaul (MRO) shop visit. These values define the life limit of life-limited components whose primary damage mechanism is low-cycle fatigue. LLPs are assigned service life caps ranging; for example, from 3,500 EFC to 20,000 EFC for hot-section parts across engine types.
An airplane's residual mechanical age is captured only by EFH and EFC, with cycles seen as the dominant payoff for structural fatigue. The engine manufacturer analyzes the typical flight profile to work out how many cycles occur per hour and to publish an exchange ratio used to schedule shop work. For example, a wide-body engine is due for an overhaul at about 20,000 EFH, although an operator will instead reach that point sooner through excess cycles during short sectors. Planes flown on frequent short routes accumulate many pressurization cycles in fewer hours, so they age faster than long-haul aircraft with higher EFH but fewer cycles. Because parts cost increases in second and third overhauls, some companies prefer to replace rather than repeatedly rebuild an engine as its cycle count rises. Predictive analytics and real-time diagnostics watch these metrics to intervene before wear becomes unsafe, employing a ‘safe-life approach’ that removes parts before it reaches an unsafe condition.
What is the durability of a jet engine?Jet engines are designed to be ultra-reliable under conditions of high stress, and with proper care many engines can remain in service for decades. These units can have lives ranging in the tens of thousands of hours of operation. Jet engines often outlast piston engines in durability and longevity. Installed on an aircraft, it endures extreme temperatures, high-altitude pressures, and rapid speed variations.
The lifespan of a jet engine is influenced by usage, operating conditions, and maintenance practices. Jet engines will go through two to three full overhaul cycles during the course of their lives, and overhaul intervals are influenced by the engine's design, model, and usage. Older and smaller jet engines generally have TBOs of up to 5,000 hours, while modern jet engines have a failure rate of about 0.01 per 1,000 hours. The Federal Aviation Administration stated turbine engines have a failure rate of one per 375,000 flight hours, and reliability went from 40 in-flight shutdowns per 100,000 engine flight hours to less than 1 per 100,000 in the late 1990s.
Jet engines are subject to wear from vibration, friction, high interior temperatures, corrosion, and physical damage from ingestion of foreign debris. Metal fatigue causes ultimate failure of parts as time passes, and adequate heat transfer away from the working parts of the jet engine is pivotal to maintaining the strength of engine materials and guaranteeing long life for the engine. Regular maintenance on jet engines ensures that all the rotating stages in an engine are balanced, and balanced rotating stages limit engine wear from vibration. Engines operate efficiently with regularly scheduled inspections and maintenance, and extending engine lifespan ensures optimal performance and safety.
