7/07/2016

The CFM LEAP LPC issue

For the first time CFM acknowledged, though not directly but through Boeing's B737MAX chief engineer Michael Teal, that the CFM LEAP-1B has an issue with the stall margin of the LPC. This was widely known in the industry for months now and in online forums like airliners.net were some hints to that issue. It is alos clear, that not only the LEAP-1B
suffered from this problem, but also the earlier designed LEAP-1A. The announced "reblading" of the LEAP-1A LPC is meant to adress this issue rather than durability problems. 
But as the teething issues of the competing PW1100G were openly discussed in the public and early customers took advantage in getting compensation for longer start-up times, the shortfall in both fuel consumption and durability that come with the open bleed between the low and high pressure compressor in the LEAP-1B and the LEAP-1A never came up in the public until now. One, and in particular PW, can only be jealous of CFM's public relations department.
As the new LPC for the LEAP-1A is only available in mid 2017, early customers will have to fly with the open bleed until their engines get fixed with the new LPC. This means higher fuel burn and higher temperatures in the turbine sections, as more fuel has to be injected to get the thrust. The whole engine is mismatched, which will have a knock-on effect on turbine durability.
Let's see how the first customers react to these issues. Probably CFM is not too unhappy with the fact, that Qatar Airways CEO "U-Turn Al" Akbar Al Baker is not their customer... 

2 comments:

  1. Has the CFM leap engine had an in-flight shutdown in Turkey?

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    1. I don't know if there was an inflight shutdown, but apparently TC-NBB, the second aircraft delivered to Pegasus, is grounded at Dalaman since October 23rd. Could be a birdstrike or something else...

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