The ATR 42 made its first flight on this day in aviation history, the 16th of August 1984. Historically the ATR 42 goes back to the development of two individual aircraft, one designed in Italy and one designed in France. They were the AS 35 designed by Aerospatiale (France) and the AIT230 designed by Aeritalia (Italy).
Aerospatiale AS 35 Aeritalia AIT230
In November 1981 both companies agreed to combine their efforts and go forward in the development and manufacture in a joint venture.
As can be seen on drawings above both companies were on the same path, and together targeted an aircraft that would cost the same as the competition (British Aerospace HS.748 and Fokker F.27), but with only half the fuel burn 950 lbs vs. 1750 lbs over a 200 nm sector for a 40 – 50 seat aircraft. Their combined efforts led to what we now know as the ATR 42, plans were also drawn up at the time for an ATR XX, a 58 seat stretched version of the ATR 42, now the ATR 72. A nice to know fact is that the “42” in the type identification is a merger of the minimum and maximum seating targeted in the design, 40 to 52 passengers.
After completing the test program, the ATR 42 was awarded its airworthiness certificate by both the French Directorate-General for Civil Aviation (DGCA) and the Italian Italian Civil Aviation Authority in September 1985. This paved the way for the first production aircraft, designated as an ATR 42-300 to be delivered to French regional airline, and launch customer, Air Littoral on the 3rd of December 1985. Based on a steady demand for orders and requests for a larger version of the ATR the company launched the ATR 72 in January 1986.
Several different versions of the ATR 42 were developed over the years
ATR 42-200 prototype on its first flight on the 16th of August 1984.
ATR 42-200 These were the prototypes, powered by P&W Canada PW120 engines, rated at 1.800 shp
ATR 42-300 Standard production version produced till 1996, powered by a P&W Canada PW120 engine, rated at 2000 shp
ATR 42-320 Improved version of the -300 with P&W Canada PW121 engine, rated at 2100 shp. This gave the aircraft better overall performance, but this was also evident in hot and high conditions
ATR 42-400 An ATR 42-320 with 6 bladed props attached to the same P&W Canada PW121 engine, rated at 2100 shp as the -320. Only 5 were built. Two civilian aircraft and 3 for the Italian government as maritime patrol aircraft, the ATR 42 Surveyor.
ATR 42-500 Powered by P&W Canada PW 127E (2.400 shp) flat rated to 45C this is another upgrade of the ATR 42. Besides the engines, new electrically controlled (composite) 6 bladed propellers were fitted, and the cabin interior was redesigned. Equipped with dual Honeywell HT1000 FMS the latest versions of the -500 have CAT II landing capability. ATR 42-600 Launched in October 2007 this version of the ATR is powered by the P&W Canada PW127M engine. It has a glass cockpit with 5 LCD screens and a complete avionics upgrade compared to the -500 giving it CAT III landing capability. ATR 42-600 is only used as a marketing identification, as it is not recognised as such by EASA. Several identifications are used, most referring to “Mod 5948” in some way, although others are also used, like "ATR 42-500 600 version" and "ATR 42-500 fitted with NAS", Other variants are a STOL variant, a Cargo variant, and a VIP variant. Some technical specifications for an ATR 42-300