AVENTURA, Florida—United Airlines is emphasizing flexibility in its next major narrowbody engine overhaul contract, seeking CFM56 support vendors that can handle both full overhauls and quick turns as well as eyeing more alternative-part usage, two of the airline’s executives told AeroEngines Americas attendees. 

“What has worked well in the past, and we’re looking to continue in the future, is the mix of a major overhaul shop with quick-turn capability,” said Nick Varner, United Airlines’ senior manager–Outsourced Engine Programs. “Not a lot of MROs have that capability, and it’s something that we’ve encouraged a lot of our vendors to pursue.”

United recently released two request for proposals (RFPs) covering 480 CFM56-7s and 40 CFM56-5Bs. One RFP is for maintenance using supplier shops. The other covers supporting work that United would in-source at its San Francisco engine shop. United does not perform CFM56 maintenance at the shop, but is considering in-sourcing some or all of the work covered in the RFPs.

“One of the things we’ve really been keen on is this ability to quickly send an engine to a small shop and return it to us,” Varner said. “It’s been a really big bonus for us, and one we’re looking to use in the future.”

United has most of its CMF56 work under a cost-per-hour program with GE Aviation, a 50/50 partner with Safran in CFM. It is open to changing both vendors and the support terms.

“As we move towards the more mature side of the lifecycle for the engine, we might very well partner with GE,” said Will Abbott, United’s director-engine vendor programs. “They’re participating with our RFPs, and we have a lot of independent MROs that are as well. But we’re pretty certain that we’re going to move away from a cost per hour program at these latter stages.”

Another key factor in keeping CFM56 maintenance costs down will be increasing the use of DER, or OEM-alternative, repairs and alternative parts, including PMAs (parts manufacturer approvals). United recently pulled its IAE V2500 overhaul work in-house, “and we’re using PMAs in that engine and constantly working with our partners to see what more PMAs” are available. 

“On our CFM fleet, we’re hoping to see more PMAs become commercially available for that program,” Abbott added.

Editor's note: This story was updated to provide more details on United's RFPs.