ATR 72

The ATR 72 is a twin-engine turboprop commercial airliner for regional and short-haul travel built in France and Italy by ATR. It was developed from the ATR 42. The ATR 72 has a maximum seating capacity of 78 and is crewed by two people.

The number "72" in its name is derived from the aircraft's standard seating configuration in a passenger-carrying configuration, which could accommodate 72 to 78 passengers in a single-class combination. To date, the entire ATR series has been completed on the company's final assembly line in Toulouse, France.

Development
During the mid-1980s, ATR
The ATR 42 is the initial version of this type and was unveiled in 1981, taking off for the first time on August 16, 1984. The ATR 72 is very similar in design to the basic ATR 42 but with an additional 4.5 meters of span and modified wings. 

The ATR 72 was unveiled in 1985 during the Paris-Le Bourget International Air and Space Show and made its maiden voyage on October 27, 1988. Exactly one year later, on October 27, 1989, the Finnish airline Kar Air became the first company to put these aircraft into service.

Design
The ATR 72 is a regional airplane with turboprop engines that can carry up to 78 passengers. It uses two Pratt & Whitney Canada PW100 engines with four or six-blade propellers from Hamilton Standard. Older models have PW124B engines (2,400 horsepower), while newer ones use PW127 engines (2,750 horsepower) for better takeoff performance at high-altitude airports like Andorra.

About 30% of the wing is made from carbon fiber, making the plane lighter. Normally, the ATR 72 doesn't have an auxiliary power unit, but when installed, it goes in the C4 cargo area. Many ATR 72 planes use a "Hotel Mode," which stops the right propeller while the engine keeps running to provide power and air on the ground.

Most ATR 72s board passengers through the rear door, which is unusual for passenger planes. The front door is often used for cargo. Finnair ordered its ATR 72s with front passenger doors to use jet bridges at Helsinki Airport. Air New Zealand uses standard rear-door models that also work with some jet bridges. A tail stand is always placed during boarding or exiting to prevent the aircraft’s nose from tipping up.

Passengers board through the rear door, while the front door is used for loading cargo.
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Category:Aircraft