CFM next month will start final assembly of the first new-generation Leap-1B engine for Boeing’s 737 MAX, as testing of the Leap-1A for the Airbus A320neo continues on track at General Electric’s (GE’s) Peebles, Ohio evaluation site.

The Leap-1A, which started up for the first time on Sept. 4, yesterday had accumulated 174 hr. and 269 cycles of test time, with no signs of “show-stoppers that we know of,” says CFM Executive Vice President Chaker Chahrour. “This engine wants to run. We are thrilled at the results of the testing we are seeing, which meets or exceeds our expectations.” The overall test and certification program will eventually consist of 60 engines, including 28 development engines for the A320neo, 737 MAX and Comac C919, the Chinese airliner project that officially launched the Leap in late 2009. The the balance is made up of compliance engines, which will power the three new airliners during their certification campaigns.

In coming weeks, the first engine is due to be taken down from the test stand, partially rebuilt and transported to GE’s site in Winnipeg, Canada, for initial engineering icing tests. “We plan to do early icing tests to really make sure we have enough time to react if any issues show up. Then we have an early block test to give us practice and confidence,” says Chahrour, referring to the triple redline or “torture test” that evaluates the engine at max fan speed, core speed and exhaust gas temperature over an extended period.

The next major milestones for 2014 will be the start of flight tests of the Leap-1C for the C919 on GE’s Boeing 747 flying testbed at Victorville, Calif., in May, followed the next month by the start of ground tests of the first Leap-1B. Although the C919 development schedule has changed considerably since the program was launched—with entry-into-service now set for late 2017 rather than second-quarter 2016—CFM has opted to stick to virtually the original schedule for engine tests.

“We’re staying on that test plan because there’s a hardware requirement that needs to come in on schedule for each of the flying testbeds. The way that comes in the sequence now is the -1C will go first. The -1C is very similar from an engine perspective and everything we learn on -1C is applicable to the -1A,” says Chahrour.

The Airbus engine will begin its own dedicated flying testbed work in the third quarter of 2014, with the MAX engine following in the first quarter of 2015.

The start of engine tests comes as CFM continues to rack up record orders for both the current CFM56-5/7, as well as the Leap models. The General Electric-Snecma joint venture so far this year has taken orders for 2,196 engines, which already outpaces the 1,972 orders booked over the whole of 2012. The 2013 orderbook is now split almost evenly between the current and next-generation engines, with bookings taken for 1,094 CFM56s and 1,102 Leap units thus far. “The two CFM product lines are doing very well so far,” says CFM President Jean-Paul Ebanga. “At this stage of the Leap program we have more than 5,000 engines already on order. In terms of backlog we are in good shape and on the CFM56 our backlog is also above 5,000.”

The sales success continues to put a greater onus on preparations for meeting delivery demands and ensuring a smooth production ramp-up. Cedric Goubet, CFM executive vice president, says the goal is to achieve an accelerated delivery curve that will see Leap production rise from zero to around 1,700 engines “within less than three years.” Overall the plan calls for around “1,700 Leaps by the end of 2018 and start of 2019, and maybe going up to 1,800 by the end of the decade.” All these numbers exceed the recently achieved historic maximum annual delivery rate of around 1,500 engines for the CFM56.