Airbus A320 single-aisle Aircraft

The original A320, launched in 1984, offered a choice of CFM-56 or IAE V2500 engines. In 2010, Airbus announced new engine options for the A320, consisting of CFM LEAP-1A or Pratt & Whitney PW1100G, hence the designation A320neo. Primarily different engines. And previous A320 was renamed to A320ceo.

CEO means “Current Engine Option” with CFM-56 and 2 others.
NEO means “New Engine Option” with CFMI-1A or P&W 1100G.

Airbus A320 family

The Airbus A320 family are narrow-body airliners designed and produced by Airbus.

• A320 – Original model (1984)
• A321 – Stretching the A320 (1988)
• A319 – Shrinking the A320 (1993)
• A318 – Second shrink (1998)

The A320 Family of aircraft are subsonic single-aisle aircraft. These aircraft are suitable for passengers and cargo commercial transport. They have two turbofan engines under the wings:

• CFM56 engine,
• IAE V2500 engine (A319, A320 and A321 only),
• PW 6000 engine (A318 only),
• PW 1100G engine (A319neo, A320neo and A321neo only),
• CFM LEAP-1A engine (A319neo, A320neo and A321neo only).

The A320 Family aircraft have:

• A standard configuration of 3 main fuel tanks (1 tank per wing and a center tank in the center wing box). One or more Additional Center Tanks (ACT) can be installed in the cargo compartments, depending on the airline configuration,
• 1 standard 2.5 in refuel/defuel coupling under the wing and 1 gravity refuel cap on each wing (related to the aircraft configuration),
• 2 twin-wheel main landing gears (standard configuration) or 2 four-wheel bogies MLG (optional, on A320 only),
• 1 nose landing gear with two wheels,
• 1 potable water tank in the pressurized section of the fuselage,
• A waste water tank,
• A lower deck forward cargo compartment,
• A lower deck aft cargo compartment,
• A lower deck bulk cargo compartment (related to the aircraft configuration).

A320 Enhanced Program

In 2006, Airbus started the A320 Enhanced (A320E) program as a series of improvements targeting a 4-5% efficiency gain with large winglets – Sharklets™ (2%), aerodynamic refinements (1%), weight savings, and a new aircraft cabin. Engine improvements reducing fuel consumption by 1% were fitted into the A320 in 2007 with the CFM56 Tech Insertion and in 2008 with the V2500SelectOne.

Wingtips – Airbus originally had small, triangular wingtips on the A320. These worked functionally but actually proved to increase drag. As a result, Airbus drew inspiration from Boeing’s blended winglet designs. This led to the development of a larger, curved wingtip called a ‘Sharklets’.

Cabin – The cabin has seen several improvements, both technologically and ergonomically. These features include better pressurization, greater luggage space, and noise reduction systems. Passengers can also enjoy LED lighting and a modern seating design for greater comfort.

New Engine Option

The Airbus A320neo family (neo for new engine option) is a development of the A320 family of narrow-body airliners produced by Airbus. The A320neo family is based on the previous A319, A320, and A321 (enhanced variant), which was renamed to A320ceo, for the “current engine option”.

Re-engined with CFM LEAP-1A or Pratt & Whitney PW1100G engines and fitted with sharklets (sharklet blended wingtip device) as standard, it is 15% to 20% more fuel-efficient than the A320ceo (Enhanced) family. It was launched on 1 December 2010, made its first flight on 25 September 2014, and was introduced by Lufthansa on 25 January 2016.

Also included on the A320neo are Airbus’ Sharklets™, which were pioneered on the A320ceo version. The 2.4-metre-tall wingtip devices are standard on NEO aircraft, and result in up to 4% reduced fuel burn over longer sectors, corresponding to an annual reduction in CO2 emissions of around 900 tonnes per aircraft. Sharklets are incorporated on new-build aircraft, and also are available for retrofit on the earlier A320ceo jetliners.

Airbus A320neo family

Airbus offers three variants of the A320neo family: the A319neo, A320neo, and A321neo. A neo variant for the Airbus A318 is not proposed but could be developed as demand arise.

• A320neo
• A319neo
• A321neo

A320-NEO-vs-CEO

The difference between a standard A320 and A320neo is clearly fuel efficiency. The changes are not mainly aimed for passenger comfort, they are meant to be more lucrative to airlines.

The neo is an evolution of the original A320.

Airbus launched A320neo on 1 December 2010. The first A320neo rolled out of the Airbus factory in Toulouse on 1 July 2014 and it made the first flight on 25 September 2014. Afterward, it entered service in 2016 when introduced to the first client Lufthansa. Moreover, the original A320 family has been renamed A320ceo.

Two of the world’s largest engine manufacturers, CFM International (CFMI) and Pratt & Whitney (P&W), launched solutions to re-engine the A320 aircraft model.

More Technical Differences – Airbus A320ceo vs A320neo

A320neo

The first A320neo entered commercial service in January 2016 with a PW1100G-JM engine (PW1127G-JM variant) and shortly after, in July 2016, the first CFMI-powered A320NEO entered service with a LEAP 1A engine (LEAP-1A26 variant). PW1100G-JM belongs to the PW1000G family of P&W and LEAP-1A belongs to the LEAP-X family of CFM International.

The new engine models are the main difference between A320NEOs and A320CEOs.

Advancements such as new options for cabin and rear galley configuration, ambiance lighting, the possibility to increase the seating capacity, are all part of the continuous product improvement efforts by Airbus in the last few years. These recent improvements developed for the NEOs can also be applied to the latest CEO vintages. Aerodynamic revisions such as Sharklet wingtips, or increased capacity from using new cabin configuration, are available for both NEO and CEO aircraft.

PW1100G-JM and LEAP-1A engines on the A320NEO

One major similarity between the LEAP-1A and PW1100G-JM series engines is their significantly larger fan diameter engines than their predecessors. This enables a higher bypass ratio, which in turn increases the jet propulsion efficiency and reduces the fuel consumption.

The PW1100G-JM engines are manufactured by Pratt & Whitney. P&W has the largest ownership stake in the International Aero Engines (IAE) joint venture, which manufactures the V2500 series engines installed on the A320CEO aircraft. The most novel feature of the PW1100G-JM is the gearbox between the fan and the low-pressure system. This enables the fan to rotate at closer to its optimum speed, which is one-third of the speed of the low-pressure turbine. In turn, this doubles the bypass ratio to 12:1 relative to the 6:1 ratio of the equivalent V2500 engine. The separation of the fan and the LPT rotation makes the LPT more efficient, which in turn allows the LPT to have less stages than an engine with a more conventional architecture. The principal differentiator of this engine is its gearbox which improves the propulsive efficiency.

The LEAP engines are manufactured by CFM International, the long-standing 50:50 joint venture between GE and Safran Aircraft Engines. Compared to the CFM56-5B, its predecessor on the A320 aircraft, the LEAP-1A has an extra stage in the high-pressure turbine (HPT) section, operates at a higher temperature, and has more advanced materials such as ceramic matrix composites (CMC) in the HPT and titanium aluminide (Ti-Al) blades in the LPT. The advanced materials allow an increase in the turbine temperature, which improves the thermal efficiency.

Wingtip devices

Sharklets are large wingtip devices with a height of 2.4m and weight of 200kg that contribute to the efficiency of an aircraft by improving the lift-to-drag ratio. Sharklets increase the lift of the wingtip while simultaneously decreasing the drag along the wing caused by wingtip vortexes, thus allowing for fuel savings and longer ranges. The benefits are comparable to increasing the span of the wings, but without doing so. Sharklets contribute to a reduction of up to 4% in fuel consumption on routes longer than 2500nm and circa 2% for routes of 500nm, when compared to wingtip fences. The longer the route, the higher the fuel-saving. Sharklets are an element of the continuous A320 family jetliner development. They can be fitted on both CEOs and NEOs. Sharklets have been available as an option on production A320CEO aircraft since 2013 and for retrofit for earlier production aircraft. They are standard fit on all A320NEO aircraft.

Passenger capacity

The fuselage dimensions have remained the same with the transition from the CEO to NEO. However, in recent years, Airbus has redesigned aspects of the interior of the A320 aircraft to enable increased passenger capacity. The available galley capacity in the aft of the aircraft has been reduced, while the two aft lavatories have been redesigned and relocated to fit into the freed-up galley space. The extra space allows the installation of at least one additional row of seats. This has increased the maximum capacity from 180 passengers to a typical upper limit of 186 passengers. The increased seating capacity is available on current production aircraft for both the A320NEO and A320CEO.

Elements of operating costs

Fuel represents one of the largest elements of operating costs of an aircraft and, industrywide, this percentage is estimated to be around 20% in the current context of moderately low fuel prices scenario. Other categories of operating costs may affect the overall share composition of fuel costs as a percentage. Other significant operational costs include crew (ca. 40%) and maintenance costs (ca. 15%), with the remainder, accounted for by navigation, ground support, and landing fees. Of these categories, the operation of the NEO should result in savings in fuel and landing fees, in addition to different maintenance costs, in comparison with the CEO. Overall, the impact of the NEO over the CEO could be seen on around 40% of the operating cost of the aircraft (the cumulative share of fuel, maintenance, and landing fees). In a higher fuel price environment, this cumulative percentage could be as high as 50% if, for example, the fuel price was to rise to over 3 US dollars per Gallon. Of these different operating cost elements (fuel, maintenance, and landing fees), the potential fuel cost savings are the most significant at over 10%. This reviews and analyzes the NEO cost differentials by three parameters – fuel price, maintenance cost, and landing fees.

Features of A320neo Aircraft

The salient features of the aircraft which is classified as A320 NEO are highlighted, as available from various documents and are stated below for necessary information.

Let’s take an example of the Airbus A320-251N fitted with two LEAP-1A26 engines to understand the features of NEO aircraft.

Electrical System (ATA-24)

IDG is accessible from the LHS fan cowl and also has an access panel on the LHS fan cowl for checking the oil level.

Equipment Furnishing (ATA-25)

The cockpit has Two observer seats. The cabin has the following features –

• Passenger cabin is a single configuration (186 Economy class) with the BE Aerospace Pinnacle seat model.
• Two Space flex Lav G & F installed at the aft.
• Aft Galley is a G4B galley.
• Extra emergency equipment storage compartment on the aft cabin bulkheads.
• Two portable ELT (Manufactured by Kannad), Model AS TNC are installed in the cabin and located as per list of emergency equipment.
• The impact activated ELT installed is KANNAD 406 AF.

Fire Protection (ATA-26)

• There is one extra loop on the fan compartment area around the length of AGB.
• All cabin fire extinguishers are of Halon free type.

Fuel (ATA-28)

• Wing tanks have inner and outer cells with intercell transfer systems as in earlier A320 aircraft.
• Two Center Tank pumps are not installed, Jet pumps and transfer valves are installed.

Ice & Rain Protection (ATA-30)

• The Nacelle anti ice system uses 2 solenoid operated pressure regulated shut off valves (PRSOV) located on LHS core compartment to allow 7th stage HPC bleed to be ducted into the air intake lip.
• EEC controls and monitors PRSOV’s operation. Two pressure transducers (PT1 & PT2) give feedback to EEC. EEC to monitor PRSOV operation.
• Other than manual deactivation procedure there is a provision for deactivation in lock open position of any one PRSOV through EEC CFDS special function menu.
• 2 PRSOVs are not interchangeable as pressure regulation settings of both are different.

Lights (ATA-33)

• Most of the lights used in Pax Cabin and Flight Deck are LED type (enhanced).
• Most of the external lights are LED type.

Oxygen (ATA-35)

• All pax oxygen boxes (PSU) contain 4 oxygen masks.
• Two crew oxygen cylinders supply oxygen to the flight crew.
• The Door / Oxygen page displays two pressures, one for the Captain’s oxygen cylinder, and the second for the FO’s oxygen cylinder.
• There are two overboard discharge indicator discs, one for each bottle, on the Left hand side forward fuselage area.

Pneumatics (ATA-36)

• Pneumatic system operates electro pneumatically and is controlled and monitored by 2 BMCs (BMC 1 & 2).
• There is one BMC for each engine bleed system. Both BMCs exchange data.
• In NEO configuration one BMC can control and monitor both sides when the other BMC fails.
• IP stage uses 4th stage HPC air and HP stage uses 10th stage HPC air.
• OPV is installed in the pylon and also has MEL dispatch provision in open position.
• Precooler is plate and fin type instead of tubular construction.
• Bleed monitoring pressure sensor (BMPS) located upstream of PRV and is used to perform bleed port switching function.
• Bleed pressure sensor located downstream of PRV provides information about bleed pressure available at the downstream of PRV.
• A Delta pressure sensor across the precooler is used for reverse flow protection.
• The dual bleed temperature sensor (BTS) installed downstream the precooler provides BMC the actual EBAS (Engine bleed air system) temperature. BMC uses this temperature for FAV control and also for over temperature and low temperature alarms.
• All Engine bleed air system valves are located on the RHS core compartment.
• Leak Detection System has one additional pylon loop.

Engine (ATA-70)

• Axial flow dual rotor variable stator high bypass ratio (11:1) turbo fan engine having thrust of 26,600 lbs.
• EGT limit – Ground starting 750-degree, Air starting 875 degree, MCT 1025 degree, Takeoff 1060 degree centigrade.
• LP spool comprises 3D woven carbon fiber composite wide chord fan blades (18), 3 stage booster and 7 LPT stage.
• HP spool comprises 10 HPC stages driven by 2 Stg HPT.
• There are 3 sumps in the LEAP-1A engine (Sump-A, Sump-B, Sump-C).
• First five stages of the HP compressor are of BLISK design (BLADE & DISC integrated).
• IGV and the first four stages of HP compressor stator vanes make VSVs.
• Combustion chamber is TAPS II (Twin Annular Pre Swirl generation II) type.
• One additional Turbine Center frame has been added between HPT and LPT.
• Fan cowl doors have both mechanical & electronic fan cowl loss prevention systems.
• Fan cowl doors have an opening / closing sequence, opening 1, 3, 2 (1 being a fwd latch), closing 2, 3, 1.
• Each Fan cowl door has 2 hold open rods, Fwd one is fixed.
• Before opening fan & TR cowl slat should be retracted and wind speed restriction to be followed.
• Engine drain system has fan zone drain, core zone drain, C sump & TRF drain (FAN & CORE ZONE have drain mast). There is no collector tank.

Engine Fuel System

• Engine Fuel System does not have HMU instead it has FMU located in the LHS FAN compartment and split control unit and servo valve assy (SCU / SVA) located in the LHS core compartment.
• SCU / SVA splits fuel from FMV (via HPSOV) into 3 parts and supplies to 2 manifolds and 19 fuel nozzles. It also delivers Servo fuel from servo fuel heater to engine air system actuators for muscle pressure. All torque motors for engine air system actuators are located on SCU / SVA.
• LPSOV is directly controlled by the master switch whereas HPSOV is not.
• Main fuel filler and strainer inside the FMU have got a bypass and ΔP sensor. There is no pop out indicator.
• All fuel components are located on the LHS FAN / CORE compartment except fuel flow transmitter & temperature sensor which are located on the RHS CORE compartment.

Engine Propulsion Control System

• Engine Propulsion Control System consists of EIU and FADEC system (EEC A, EEC B and Pressure subsystem) for each engine.
• Each EEC has got 9 connectors. PSS has got 2 electrical connectors, 4 pressure sensor connections (P0, P12, PS3, P3B) and 1 data entry plug connection.
• Temp sensors connected to EEC are T12, T25, T3 and T48 (EGT).
• In this engine PMA (oil cooled) supplies power to EEC when N2 >8%. PSS does not have separate power supply. Each PSS channel is supplied via its corresponding EEC.
• EEC changeover takes place after every start when N2>70%.
• All FADEC system components are located on the RHS FAN compartment including blowers.
• TCMA (Thrust Control Malfunction Accommodation) – This is an additional protection provided by EEC to prevent overboosting / overspeeding.
• In case of FADEC power off, all secondary parameters will show amber xx in addition to primary parameters.
• EIU is not interchangeable / intermixable with CFM56-5B EIUs.

Ignition System

• Ignition system components are located at the 6 O’clock position in the core compartment. Igniters are located at 5 & 7 O’clock in the combustion case.

Engine Start System

• Pneumatic Air Starter (PAS) is located in the LHS Fan Compartment on AGB. It takes oil from AGB, no separate oil servicing required.
• Start air valve is located on the starter duct at the upstream of PAS accessible from the LHS fan cowl. Qty Two position transducer provides its position feedback to EEC (No micro switches).
• For manual start valve opening there is a small flap type access hole located on the LHS Fan cowl.
• Starter duty cycle is 3 consecutive cycles, each has a maximum of 2 min, pause between start attempts 60 sec. Cooling period after 3 start attempts is 15 min.
• LEAP 1 A engine has got adaptive start feature (to delay fuel and ignition by maximum 60 sec to counter bow rotor start condition).

Engine Air System

• LEAP-1A engine has VBV VSV, TBV, SB / BAIV (Start bleed / booster anti-ice valve), MTC (Modulated Turbine Cooling) HPTACC & LPTACC Valves. All valves are Torque motor operated. VBV, VSV & MTC have 2 actuators and others have single actuator. MTC, HPTACC & LPTACC valve has MEL dispatch provision. NOTE (VBV has eight inward opening VBV doors, not twelve).
• SB / BAIV – is a rotary valve which bleeds HPC 7th stage air during a certain start attempt as decided by EEC and also heats the splitter fairing leading edge to avoid ice formation.
• MTC Valve – Reduces HPT 1St stage turbine blade cooling at low power to decrease specific fuel consumption and increase cooling air flow from HPC 10th stage by opening two MTC valves at high power.

Engine Control

• An additional soft go around (SGA) thrust limit mode features in LEAP-1A engine by EEC software to reduce unnecessary fuel consumption during Go around, if the pilot moves the throttle lever from TOGA to MCT / flex detent.

Engine Indication

• N1 speed sensor is located at 4 O’clock fan frame strut.
• N2 speed sensor is located on Transfer shaft housing near AGB.
• 8 dual thermocouple EGT sensors are located around TCF at the inlet of LPT.
• No.1 bearing accelerometer is located at 3 O’clock position on Fan case, TCF accelerometer is located in 12 O’clock position on turbine centre frame. Only TCF accelerometer is LRU. There is no EVMU, EEC does this function.

Thrust Reverser System

• Consist of Two upper Synchronized locking feedback actuators (SLFA), synchronized manual locking actuator (SMLA) on lower RHS, synchronized non-locking actuator (SNLA) on lower LHS, Isolation control unit (ICU), Direction control unit (DCU), two translating cowls, ten blocker doors, cascade vanes and one Electrical tertiary lock. Both lower actuators are having manual drive provision. Two upper actuators have LVDTS and proximity sensors.
• Electrical Tertiary Lock (ETL) is an electromechanical lock located at 6 O’clock position on the left latch beam of thrust reverser to prevent inadvertent deployment in flight. MEL dispatch for flight requires deactivation of ICU and locking LHS translating sleeve with C duct by means of long ‘Red’ deactivation pin stowed on LHS T/R cowl bulkhead.
• GASS (GROUND ASSISTED STOW SEQUENCE)-EEC initiates GASS operation on ground to lock T/R SYSTEM if one primary lock is detected unlocked after normal stow sequence or after engine start.

Engine Oil System

• All oil system components are located on the LHS fan compartment except the oil tank and ODMU (oil debris monitoring unit) which are located on RHS.
• Surface Air Cooled Oil Cooler (SACOC) – is a matrix type air oil cooler in the oil supply circuit composed of 2 segments symmetrically installed on both inner surfaces of the fan frame rear side. It uses secondary airflow to cool the engine oil.
• Oil Debris Monitoring System – ODM sensor is mounted on an air oil separator inside the oil tank. Metallic particles from scavenge oil are collected in a collector ring of ODM Sensor which generates an electrical signal proportional to the amount /size of the particle and sent to the ODM unit.
• Above a definite threshold ODM unit sends electrical signals to EEC B to provide ECAM warning about chip detection. OPV (Oil Pressurizing Valve) located at the outlet of the main heat exchanger enables pressurized oil to feed engine oil dampers. Scavenge Screen Plugs are fitted on the lube unit, one is triple stage and other is dual stage. Eductor Valve allows 7th stage HPC air to bleed thru center vent tube venturi in order to increase differential pressure across fwd sump seal to prevent oil leak at low rpm. It opens at low pressure and closes when pressure increases.
• In order to maintain the uniformity in Oil uplifting requirements, whenever oil quantity decreases to 16 Qts or lesser (ECAM Level) then immediate uplifting of oil to be carried out till level of 17.1 Qts (ECAM level) – i.e. equal to Oil tank Full mark in the sight glass) as per AMM task.
• Since the oil tank is pressurized it is MANDATORY not to open the oil tank filler cap for oil filling before 5 min after shutdown.

The above is for general information about A320-251N NEO aircraft fitted with LEAP-1A Engine for all concerned but all concerned must refer to Technical documents from Airbus.

Summery

The A320 Family is the world’s best-selling single-aisle aircraft. An A320 takes off or lands somewhere in the world every 1.5 seconds of every day, the family has logged more than 117 million cycles since entry-into-service and records best-in-class dispatch reliability of 99.7 %.

To ensure this true market leadership, Airbus continues to invest in improvements in the A320 Family: enhancements to aerodynamics such as the sharklet wingtip devices, upgrades to the widest passenger cabin in its class, the A320 Family neo. The latter combines top-of-class engine efficiency offered by two new engine options: the PW1100G PurePower from Pratt & Whitney and the LEAP-1A from CFM International with superior aerodynamics offered by the new sharklet devices.

The A320neo family offers a minimum of 15% fuel savings and an additional flight range of about 500 nm (926 km) and up to 20% fuel savings achieved through cabin innovations and efficiency improvements. For the environment, the A320neo family is also more eco-friendly, with 5000 t (11 023 113 lb) less CO2 emissions per year per aircraft and nearly 50% reduction in noise footprint compared to previous generation aircraft.