The two big engine makers in the single aisle market now are more easily compared as more data emerges. Both firms have to file documents with the US FAA. This information provides an insight we have not seen to date. The CFM LEAP data can be seen here (E00089EN_Rev_1) and the P&W GTF data can be seen here (E00087EN_Rev2). For data on the CFM56 look here (E37NE_Rev_13) and the on the V2550 look here (E40NE_Rev_10). The documents make interesting reading.
The table summarizes some key numbers.
Airbus, in its Orange Book, wants to ensure that both engines are equal or at least equivalent. They do not want any bias in engine offerings.
Intriguingly when looks at the CFM LEAP data filed with the FAA, you will notice there are two variations in the engines. There are big differences in engine weight for the LEAP G01 and G02 variants. We checked with CFM about the FAA documentation. This is how the weight change is explained. The LEAP nacelle is produced by Aircelle (Safran). Upon reviewing the nacelle installation procedure, Airbus, Aircelle0000, and CFM determined that it would be more efficient for CFM to own a portion of the Engines Build-Up Unit (EBU) hardware – tubing, brackets, etc. – rather than Aircelle. Consequently, on the G02 engine, the weight of the EBU is now included in the engine weight rather than with the nacelle weight. Overall propulsion system weight (engine, nacelle, thrust reverser) remains the same. The 35A was the engine specification certified November 20, 2015. The G01 engine was a configuration CFM needed to have for flight testing – this engine will never see commercial service. From G02 forwards is the engine that will enter commercial service with Airbus. CFM points out their engine is at spec.
What is interesting though is to see how the current generation engines compare with the next generation. The new engines are much heavier. Of the two engine OEMs, it appears (according to the data filed with FAA) the V2500 is 3.9% lighter than its CFM56 equivalent. For the newer engines, the GTF is 4.4% lighter than the LEAP equivalent.
© 2016, Addison Schonland. All rights reserved.