The cost of the life limited parts continues to be a major cost item for operators and even with the recent agreement between the CFM and IATA over the use of PMA parts, the current situation will likely not change in the near term.
Engine technology has advanced significantly from the 1960s and 1970s when engines were replaced at very regular intervals not least because of in flight failures, hence the reason why there was a preference for three or more engines. While engine reliability has greatly improved the cost of engine maintenance has increased exponentially with life limited engine parts increasing beyond the rate of inflation due to ever increasing sophistication. The first casting of a copper frog in Mesopotamia 6,000 years ago through the lost wax method may have facilitated todays aero-engines but current engines have become lighter through the use of nickel superalloys which allows much higher operating temperatures compared to steel but exhaust gases are higher than the melting point of the material. Engine parts therefore also need to incorporate cooling vents, thus making their manufacture that much more complex. Single crystal manufacturing techniques allows engine parts to also cope with the extreme forces being imposed. The need to virtually control the formation of the blades atom by atom makes for an expensive manufacturing process and is one which has not as yet been fully automated. The very expensive engineering facilities and the relatively limited production runs have inevitably ensured that the cost of manufacturing the parts has continually risen. This ensures that while reliability and the life of the parts has increased, so too has the expense. The manufacturers have perhaps needed to increase the cost of the LLPs in excess of general inflation to cover the cost of development and the manufacturing facilities.
For the A320ceo powered by CFM56-5B4/P or /3 engines, the cost of a full set of LLPs costs approximately $3.6 million. the LLP life ranges between 20-30,000 cycles depending on the component. This compares with the LLPs costing some $2.0 million as of 2009 and clearly illustrates the significant rise in costs for both manufacturer and operator. For the IAE V2500 engine, the cost of the LLPs is higher at $$3.9 million with the cycle limit generally being 20,000 cycles. Consequently, the cyclic cost of the CFM engine in terms of the LLPs is lower than that of the V2500 while the on wing time is generally higher. Mitigating against this higher LLP cost though is the higher cost of engine overhaul of the CFM engine which in turn needs to be seen in the context of the installed engine price which may have also been higher. For the B737-800 with CFM56-7B27E engines, the LLP cost also approximates $3.6 million. For the A320neo, the LLP cost is approximately $4.3 million even as the life of the components remains the same at 20-30,000 cycles although for the PW1127G the cost is likely to more approximate $4 million. The LLP cost is therefore higher for the A320neo. The cost of the LLPs does not change to any significant degree for the higher thrust options fitted to the A321ceo or A321neo.
For the widebodies, the cost of the LLPs for the CF6-80E1A4 used on the enhanced A330ceo is likely to be in the region of $11 million based on a life of 15-20,000 cycles. However, this compares with less than $9 million for the PW4000 and less than $6 million for the Rolls-Royce Trent 700. Again, the cost of the LLPs on the A330 need to be viewed in the context of the cost of overhaul with the CF6 and PW4000 costing some $4-5 million and the Trent 700 $9-10 million. With respect to the CF6 and PW4000 used on the B767-300ER the LLP cost is approximately $7 million. For the B787-8 the LLP cost of the GEnx is likely to be around $8.5 million versus just over $7 million for the Trent 1000 although the cost of the overhaul for the GEnx is lower than for the Trent 1000. When it comes to the LLPs for the B777-300ER the list price of a set can be expected to be approximately $9 million based on a 15,000 cycle life. With respect to the Trent 900 used on the A380 the LLP cost may be some $7 million with a life of 15,000 cycles.The list prices indicated by the manufacturers may not actually be the cost paid by the airlines and can be lower. The criteria for determining maintenance reserves will differ considerably from end of lease compensation arrangements.