The Signature Attributes of the A320 Family [EN]

Which planes belong to A320 family ?

The A320 family is composed of A318, A319ceo, A319neo, A320ceo, A320neo, A321ceo, A321neo, A321neoLR, A321neoXLR.

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Why the A320 family is the most successful aircraft family ?

Fuel efficiency.

       The A320 family is known for its fuel-efficient design, incorporating advanced aerodynamics features, lightweight materials and modern engines for the latest A320neo family. Fuel efficiency is critical factor for airlines, as it directly impacts operating costs.

Range and versatility.

         The A320 family covers a large range of seating capacities until 220 passengers for the A321neo in a typical two-class interior layout and can be increased to 244 passengers in a higher-density arrangement. Aircraft in this family have a range of between 5700km and 8700km. This wide range of options allows companies to choose the aircraft that is best suited for their operational requirements.

Market demand.

The A320 family meets most of the demand for narrow-body aircraft, which are the best choice for airlines to operate short to medium-haul routes. Airbus commitment to innovation and enhancement has helped the aircraft family to stay competitive in the market.

To conclude, a combination of fuel efficiency, design innovation, professionalism and global customer support had contributed to the success of the A320 family in the commercial aviation industry.

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An interesting particularity on A320 family aircrafts: The “barking sound”.

What sound are we talking about?

If you're a frequent flyer on A320 family aircraft, you've probably already heard that famous noise, and wondered where it comes from and whether it's normal. Don’t worry, this noise is totally normal, and we're going to explain it to you.

To understand it, it's essential to look at the entire hydraulic system on an A320.

The hydraulic system plays a fundamental role in the smooth operation of an aircraft. It operates virtually all the flight controls (flaps, aileron, elevator, etc.).

The A320 family has 3 hydraulic circuits. Thanks to these devices, in the event of failure of one of the hydraulic circuits, the aircraft is always under control.

The aircraft of the A320 family have 3 hydraulic circuits. It is thanks to these devices that, in the event of a breakdown of one of the hydraulic circuits, the aircraft is always under control. Indeed, knowing that the hydraulic system is responsible for actuating the flight controls, a failure could be catastrophic.

       Source: A320 Fuel Control Panel, Lustublog.

To understand the situation properly, it is important to understand the A320’s hydraulic system.

So let’s focus on the A320's hydraulic system:

          Source: hursts.org.uk

The green circuit can be pressurized by a mechanical pump on motor 1.

The yellow circuit can be pressurized by a hydraulic pump on engine 2, but also by an electric pump (useful on the ground, when the engines are not running) and an emergency manual pump.

The blue circuit can be pressurized by an electric pump and an emergency turbine (located under the fuselage of the aircraft) which can be triggered if necessary, known as the RAT.

To operate correctly, these 3 circuits must be pressurized to around 3000 Psi.

(The PSI or Pound-force/square inch is the Anglo-Saxon unit of pressure measurement. This unit of measurement, symbol PSI or psi, has a value of 6.89476 kPa (KiloPascal)). 

A system called PTU (Power Transfer Unit) allows the yellow circuit to be pressurized by pressure from the green circuit, or vice versa. As you can see from the schematic, it acts as a link between the two circuits. In case of a pressure difference between the yellow and green circuits exceeding 500 Psi for more than 6 seconds, the PTU is automatically activated to re-pressurize the weaker hydraulic circuit.

So, where does this sound come from?

This famous noise comes from the PTU, which, when engine 1 is started (and engine 2 is in the process of starting up), it will pressurize the green circuit, and a difference of over 500 Psi will be detected between the green and yellow circuits (as the yellow circuit is not yet pressurized), automatically triggering the PTU, which will pressurize the yellow circuit. This scenario takes place before the departure of our aircraft, in the parking lot.