New Progress Report on MC-21 Raises Questions about PD-14 Engine MRO
Chris Kjelgaard, New York
The revelation in a detailed new MC-21 programme progress report issued by Irkut on December 21 that the new Russian-made PD-14 high-bypass turbofan is now in its second stage of flight-testing raises questions about the future MRO arrangements for the engine, as well as its market prospects.
Developed by United Engine Company (UEC) subsidiary Aviadvigatel, the PD-14 was designed as an alternative to the Pratt & Whitney PW1400G geared turbofan to power the Irkut MC-21, the Russian aerospace industry’s new single-aisle competitor to the Airbus A320neo and Boeing 737 MAX families.
The PD-14 isn’t a geared-turbofan engine like the PW1000G and doesn’t incorporate ceramic matrix composite parts as does the CFM LEAP family, but it does have other technology features which are in line with the current state of the art in Western commercial-turbofan engine design.
Aviadvigatel designed the PD-14 to offer specific fuel consumption 15 per cent better than current-generation Western engines such as the CFM56 family and the IAE V2500 and to offer 99.96 per cent dispatch reliability, the design bureau notes on the PD-14 page of its website.
Having completed a 16-flight first round of flight-testing on an Ilyushin Il-76LL flying testbed, the testing beginning on November 3, 2015, Aviadgatel planned a second round of flight-testing to take the PD-14 halfway to type certification, planned for late 2017 or early 2018. However, to date Aviadvigatel hasn’t indicated it has begun the second round of PD-14 flight-testing.
Now, confirmation from Irkut that the second round of PD-14 flight-testing is underway provides new impetus for the commercial-aviation industry to ask what MRO support arrangements Aviadvigatel might be contemplating for the PD-14 once it achieves type certification and enters service.
Although to date the PD-14 has only been ordered by two Russian customers for the MC-21, it is worth noting Aviadvigatel’s ultimate parent company Rostec (which owns UEC) has placed firm orders for 50 MC-21s (35 MC-21-300s, the reference 180-seat version of the aircraft, and 15 lower-capacity MC-21-200s) and secured options for 35 more aircraft.
To date the PD-14 has only been ordered by Russian customers for the MC-21. But it is also worth noting that, earlier this year, Aviadvigatel indicated once the PD-14 receives type certification it hopes to secure agreements with aircraft manufacturers in the emerging BRICS economies to offer their aircraft with PD-14 engines installed.
Should Aviadvigatel succeed in securing any such agreements (certainly a possibility given that the PD-14 is likely to be priced at a level well below the competing Western engines), the question of MRO support internationally for the PD-14 could become compelling.
Irkut’s signing of a memorandum of agreement with Lufthansa Technik to provide MRO support for the MC-21 and its cooperation with companies such as Technic One on providing MC-21 components pools (as discussed in the August 17 Talking Point column) could signpost a possible route to arranging comprehensive international MRO support for the PD-14.
In addition to revealing that the second round of PD-14 flight-testing is underway, Irkut’s detailed new MC-21-programme progress report suggests the company is well on the way to ensuring a spring 2017 first-flight date for the MC-21-300, which will be the first version of the MC-21 to fly.
In the 18-page presentation, Irkut notes that the designated first MC-21 to fly, MC-21-300-0001, is being prepared for flight-testing. Its fuselage has been tested to ensure it is airtight; on-board measurement systems and equipment have been installed; aircraft systems are undergoing adjustment; the aircraft’s electrical power has been switched on; and frequency-response tests to identify the MC-21’s natural oscillation frequencies have begun.
Meanwhile, MC-21-300-0002, the second airframe, to be used as a ground-test airframe, is completing additional assembly for static testing, which will be conducted at the TsAGI Central Aerohydrodynamic Institute, located at Zhukovsky Airfield near Moscow.
Manufacturing of components, units, and assemblies is complete for МС-21-300-0003 and МС-21-300-0004, both of which will be flight-test aircraft. Final assembly of MC-21-300-0003 aircraft is underway at the Irkutsk Aviation Plant in Irkutsk in Siberia.
Various static strength tests on hundreds of samples of MC-21 major structural elements have been completed. Structures for which Irkut has completed static strength testing include the MC-21’s fin, horizontal stabilizer, landing gear, and full-scale samples of its carbon-fibre composite high-lift devices and empennage – flaps, aileron, air brake, spoilers, elevators, and rudder.
Additionally, Irkut has tested four scaled-down prototypes of the MC-21’s composite wing box and testing of a full-scale wing box is underway.
Irkut has also performed a considerable amount of endurance testing on MC-21 fuselage sections. The main fuselage section has now accumulated more than 47,000 simulated flight cycles and the fuselage tail section has passed 240,000 cycles.
Various MC-21 structures have already completed environmental and durability testing and similar testing for other sections is about to begin. The MC-21’s nose and fin sections have successfully passed bird-strike testing at maximum aircraft speed; and its windshield, radome and nose landing-gear door have successfully passed certification testing ensuring they can withstand direct lightning strikes and dissipate the resulting static discharges.
Irkut is now preparing the MC-21’s stabilizer for bird-strike testing and its high-lift devices and empennage for environmental static and life-cycle tests.
The company is using more than 100 test benches, including four integration benches, to test and refine the MC-21’s aircraft systems, equipment and structural elements. These tests are being performed at TsAGI, Moscow-located GosNIIAS (the State Research Institute of Aviation Systems) and an organisation named Airspace Systems DB.
The four integration test benches Irkut is using for MC-21 systems testing include:
● A test bench for MC-21 electrical-power supply systems;
● Irkut’s MC-21 ‘Iron Bird’, which is testing the aircraft’s hydraulic systems and machinery (including hardware-in-the-loop simulation of its integrated flight control system and general equipment-control system);
● The company’s MC-21 ‘Electronic Bird’, an avionics-suite test bench; and
● A test bench for electronic and hardware-in-the-loop simulation of the MC-21’s integrated flight control system.
On the Iron Bird, Irkut has completed the first stage of landing-gear functional testing (extension, retraction and steering) and is now testing the MC-21’s integrated flight control system and hydraulic system.
Irkut has used the test bench for electronic and hardware-in-the-loop simulation of the MC-21’s integrated flight control system to test the MC-21’s control-law algorithms and aircraft controls.
The company reports this bench-testing has completed the full scope of development and test-pilot assessment of the MC-21’s control-law algorithms and hardware, as well as testing manual control of the aircraft and engines in simulated flight.
Independent testing of the MC-21’s integrated flight control system is now being performed and flight crews are being trained for its first flight.
On the Electronic Bird, Irkut is performing integration of all the MC-21’s electronic airborne systems into its avionics suite. A prototyping test bench which is a component of the Electronic Bird is developing and supervising the MC-21’s overall flight-deck indication-and-signalling concept.
Irkut says it is close to completing the work needed to create new facilities for MC-21 flight-test programme infrastructure at the Irkutsk Aviation Plant in Irkutsk and the Yakovlev DB Flight Test Facility at Zhukovsky Airfield. The company is also working to install a new flight information-processing facility in the new hangar at Zhukovsky.
Last but not least, Irkut has built MC-21 pilot-training simulators and a procedural simulator; it has installed a KTS MC-21-300 full-flight integrated simulator with motion system; and it is close to completing the manufacture of cabin-simulator prototypes for flight-attendant training.