The Airbus A320 is the first aircraft to be certified with the Pratt and Whitney (PW) Geared Turbofan (GTF) Engines. The GTF engines are revolutionary, moving somewhat closer to a turboprop with the presence of the reduction gear-drive. The A320neo (new engine option) variant with the PW 1127G-JM engines, the A320-271N, has run into a spot of bother, which has made Qatar and IndiGo refuse the aircraft with its present restrictions. Lufthansa is now the launch customer of the neo.
According to Air Transport World (ATW), “…operational restrictions are still in place for the Pratt & Whitney PW1100G engine, pending some hardware and software changes”. This restriction requires the engines to idle for three minutes before the aircraft can commence taxi. Qatar will not accept a part-baked product, and IndiGo will not operate an airplane that will mess with its strict turn-around schedule.
The 5th production Airbus A320neo (-271), MSN 6801, is slated for Lufthansa, to be registered D-AINA. The 11th production A320-271N, MSN 6864, to be registered D-AINB, is the second A320neo slated for Lufthansa. The remaining A320neos upto the 11th are slated for Indigo (5), Qatar (2), and Spirit Airlines (1). Both are assembled at the line at Hamburg (Germany). The first A320neo is planned by Lufthansa to be introduced into commercial service in January first week, according to ATW.
With Lufthansa stepping up as the launch customer, Qatar will become the second operator to induct the A320neo, and IndiGo the third. Go air is slated to receive the 23rd production A320neo (-271N). IndiGo will then receive its neos only in early 2016, as had originally been widely speculated, based on other issues the engine had earlier faced.
The Pratt and Whitney GTF engine, by virtue of its new technology, will have its share of issues till the engine matures, as is the case with almost every new engine. While the GTF optimises propulsive efficiency through the use of a reduction gearbox to drive the three stages of the engine at optimal speeds, the alternate engine to power the A320neo, CFM’s LEAP-1A, optimises thermal efficiency by running the combustion chamber much hotter, relying heavily on material technology to withstand such temperatures. According to Aspire Aviation, the CFM engines have underperformed on fuel consumption, and is facing issues related to both component heating, and cooling mechanisms.
While IndiGo and Go Air will bear the brunt of the bound-to-happen hiccups as the engine matures, Vistara, which is yet to make a decision on its engines in the first half of 2016, will receive its leased neos only in the second half of 2017. The airline will have good time to keep a close watch on the PW1127G-JM engine performance and reliability to make a better informed decision. While the aircraft and engine certification programme put the aircraft through extreme tests, it is also a known fact that Indian operating conditions are harsh for engines. Prolonged operations in Indian conditions will truly test the A320-271N.
Air India has apparently not yet decided on leasing neos in the short-medium term.
The PW1100G-JM family of engines uses a revolutionary but not new technology that essentially makes the engine a cross between a turboprop and a pure turbofan. This is the largest geared turbofan produced till date. With this engine, Pratt and Whitney marks its return as a single brand powerplant option for narrowbody mainline jets. Boeing 737-300/400/500/600/700/800/900/MAX-7/8/9 are all powered by CFM engines, while the Airbus A320 family of aircraft are powered by either CFM or the IAE consortium’s engines. Pratt and Whitney is part of the IAE consortium.
The “JM" in PW1127G-JM represents partner companies Japanese Aero Engine Corporation (JAEC) and (Motoren- und Turbinen-Union GmbH) MTU. JAEC holds a 23 percent share in the PW1100G program and is responsible for the fan, low pressure compressor (LPC) and combustor/diffuser. MTU holds an 18 percent share and is responsible for the low pressure turbine (LPT), and jointly with Pratt & Whitney the high pressure compressor (HPC). Pratt & Whitney is responsible for the remainder of the engine and systems integration.
The PW1100G-JM family powers the Airbus A320NEO family (A319NEO, A320NEO, and A321NEO) and is available in 5 thrust variants of 22,000/24,000/27,000/30,000/33,000 lbf (pound-force) per engine. The PW1127G-JM that powers the A320NEO is the 27,000 lbf variant.
The CFM powered A320NEO (A320-251N) will be certified in the coming months.
In India, all operators that have placed direct orders for Airbus A320NEO aircraft have chosen the PW1127G-JM as the power plant of choice. IndiGo has 430 Airbus A320NEOs on order, some of which may be converted to A321NEO orders. Go Air has an order for 72 Airbus A320NEO aircraft. Vistara, which is committed to the lease of 20 Airbus A320 aircraft from Bank of China Aviation (BOC Aviation), will receive 7 Airbus A320NEOs from mid 2017 onwards. However, the engine option has not yet been finalised. AirAsia India, which leases aircraft from AirAsia Berhad, will receive Airbus A320NEOs powered by the CFM LEAP engines.
One of IndiGo’s Airbus A320NEOs, MSN 6720, is one of the three test aircraft, and has been flying since September 25th, 2015. However, the first production aircraft is destined for Qatar Airways, the launch customer. MSN 6744, to be registered VT-ITA, a Hamburg produced A320NEO already painted in airline colors, may be the first A320NEO for IndiGo, despite being produced after the aircraft that was already flying for the certification program.
The three flight test aircraft powered by Pratt & Whitney engines accumulated over 1,070 flight hours over 350 flights. Of these 1,070 flight test hours, 300 were completed with the same aircraft in an airline like environment to ensure operational maturity at entry into service.
The A320-271N is the 9th sub-variant of the A320-200 family, after A320-211/212/214/215/216/231/232/233. The A321-271N is ‘significantly different’ from the original A320 Type certificate via the modification labelled “MOD 161000”. Pratt and Whitney received FAA certification for the PW1100G-JM engine on December 19th, 2014.
The A320-271N’s operating empty weight is around 3 tonnes heavier than the A320-232 which IndiGo flies today. However, the maximum take-off weight of the highest weight variant of the A320-271N is 79 tonnes, which is just 1 tonne higher than the maximum take-off weight of the highest weight variant of the A320-232. The dry weight of each PW1127G-JM engine is 453kg heavier than the IAE V2527-A5 that powers the -232 variant. This implies that the weight of accessories and structural reinforcements total to around 2 tonnes.
The A320-271N promises a fuel saving of upto 11% over the A320-232SL and 15% over the A320-232 (non winglet). Such savings are however realised only on flights of 3000NM and higher.
There is a strong possibility of IndiGo receiving its first Airbus A320NEO by end of this calendar year. As per our information, IndiGo’s A320NEOs will be fitted with 186 seats – six seats more than what it fits every aircraft cabin with, today.
Thanks to Cyril for the heads up on the certification.
Edit (30th Sept): Edited to include the first flight of the first production A320NEO, which is destined for IndiGo. Edit includes a confirmation of a Space Flex cabin.
Indian domestic market leader IndiGo’s first Airbus A320 NEO (New Engine Option) – part of the July 2011 order for 180 aircraft, has rolled out of the Hamburg (Germany) final assembly line fully painted in the airline colors, but without the Pratt & Whitney Geared Turbo Fan (GTF) Engines. This is the third such airframe of the airline. Two have no engines fitted. The cabin has not been fitted yet.
MSN 6720, destined for IndiGo, first flew on September 25th at Toulouse, France. The aircraft fuselage has however not been painted in the airline’s colors, but the wings are in the airline’s markings. MSN6720 is the 6th NEO to be produced, and the first ‘production’ NEO. The to-be Indian Registration of MSN 6720 is yet unknown, but will likely be the first A320 NEO for IndiGo.
A320-271N MSN 6744, which is expected to be registered VT-ITA, is the 7th NEO produced, and likely the second for IndiGo. A320-271N MSN 6799, to be registred VT-ITC, is likely IndiGo’s third A320 being assembled at the Toulouse (France) final assembly line, and is the 9th NEO to be produced. All Airbus A320 NEOs that IndiGo will accept will be powered by the Pratt & Whitney PW1127G engines.
The same engines had a problem with a clip holding seals inside the engine. This had caused concerns on the NEO program schedule, which has invariably slipped a bit. However, launch customer Qatar Airways expects to receive the first aircraft by the end of the calendar year. Interestingly, Qatar’s A320 NEO is MSN 6772 – the 8th NEO – which means it is later down the assembly line sequence when compared to IndiGo’s 6744 and 6720.
The NEOs rely on the sharklets and new, ultra-high bypass geared turbofan engine technology to together deliver fuel savings of upto around 15% (over and above today’s CEO A320’s without sharklets) . Such high fuel savings will however be realized only on very long flights that approach the maximum range of the airplane.
Airbus’s “Space Flex” concept allows airlines to increase the seating capacity of the Airbus A320 (both current engine options (CEO) and NEO) to 189 seats, without compromising on seat pitch and comfort. This is achieved by moving the two rear lavatories closer to the bulkhead, eating into the galley space. This makes more sense to no frills carriers which do not carry much meals on board. The space for service trolleys in the aft galley of the aircraft reduces from 7 to 3. The space where the aft lavatories were fitted are replaced with 1.5 rows of seats.
This increase in number of seats reduces unit costs by 5% to 6%. It is not known if IndiGo will adopt the space flex concept yet. No physical changes to the emergency exits are required. However, opting for a mix of 189 seat and 180 seat A320s may reduce operational flexibility for the airline. Opting for a higher capacity however seems inevitable.
IndiGo is believed to have opted for the Space Flex cabin, but details on when it will appear are not known.
There is a buzz about the PW1100G Geared Turbofan Engine from Pratt and Whitney, that will power the first A320NEO. The PW1100G is a family of ultra-high bypass engines, part of the PW1000 series. The Flying Engineer welcomes you to enjoy the most technical take on the engine, that will leave you either educated, or snoring on your chair. Grab that coffee, and appreciate the next big thing in jet transport as we know today: Geared Turbofan Engines.
In this article, we explore, at a high level, the design of the PW1100G family, how it compares with existing A320 engines, the differences, on a high level, of this family with the competitor’s offering: the LEAP 1A, why the Boeing 737MAX family doesn’t need such a large turbofan engine, and finally, before concluding, the pros and cons of such an engine.