Airbus A310-300

The A310 was born as a medium-range aircraft, but Airbus soon added a second version aimed at longer routes. The A310-300 first flew on 8 July 1985. It is dimensionally identical to the A310-200: it shares the fuselage, wing and tail, and what changes is the fuel it can carry and its maximum take-off weight. In Wikipedia's comparison table, the -200 stops at 144,000 kg maximum take-off weight and some 3,500 nautical miles of range, while the -300 reaches 164,000 kg and 5,150 nautical miles (9,540 km) with 240 passengers at long-range cruise. Over time it displaced the -200 as the programme's standard production version.

The decisive technical novelty of the -300 is a fuel tank inside the horizontal stabiliser. The EASA type-certificate data sheet credits it with 4,920 kg of usable fuel (6,150 litres), within a usable total of 48,872 kg (61,090 litres) spread across the outer, inner, centre and trim tanks. The tank does more than add endurance: a computerised fuel distribution system, controlled by the Centre of Gravity Control Computer, shuttles up to 5,000 kg of fuel into and out of the tail to optimise the centre of gravity in flight and improve fuel efficiency. For even longer range, the cargo hold could take one or two auxiliary centre tanks; with both fitted, total capacity rises to 68,300 litres according to aircraftinvestigation.

From 1985 onwards the -300 introduced wingtip fences, small delta-shaped surfaces at each wing tip that reduce vortex drag and, according to Wikipedia, cut cruise fuel consumption by over 1.5%. They are the feature that sets the -300 series apart at a glance, although they were later retrofitted to some -200s and late-series -200s already left the factory with them.

The EASA type-certificate data sheet groups five models in the -300 series, distinguished by powerplant: the A310-322, with Pratt & Whitney JT9D-7R4E1, certified on 5 December 1985; the A310-304, with General Electric CF6-80C2A2, on 11 March 1986; the A310-324, with the PW4152, on 27 May 1987; the A310-308, with the CF6-80C2A8 or CF6-80C2A2, on 5 June 1991; and the A310-325, with the PW4156A, on 6 March 1992. Wikipedia gives the CF6-80C2A2 238 kN of thrust and the PW4152 230 kN, and notes that from late 1991 the more powerful CF6-80C2A8, at 260 kN, and PW4156A, at 250 kN, became available.

The -300's longer range took it onto transatlantic routes, which required ETOPS approval: flying with only two engines far from diversion airports. The approvals table in the EASA data sheet shows the progression. The A310-304 gained 120-minute approval in stages — on 10 April 1986 with a 90-minute diversion time, on 18 May 1987 with 105 minutes and in full on 14 September 1987 — and 180-minute approval on 27 July 1990. The A310-322 received 120-minute approval on 10 April 1986 and 180-minute approval on 27 July 1990. The A310-324 went through the 90-minute stage on 28 March 1989 and reached 120 minutes on 30 October 1989; its 180-minute approval came on 3 September 1991, the same date as the A310-308's, and the A310-325 obtained it on 11 March 1992.

The -300 was certified with a long series of weight variants. The EASA data sheet lists maximum take-off weights ranging from 134,000 kg (variant 07) to 164,000 kg (variants 08 and 13), with 150,000 kg for the basic one; maximum zero-fuel weight reaches 116,500 kg on variant 13. Airbus's airport planning document estimates an operating empty weight of 79,207 kg with CF6-80 engines, 77,397 kg with JT9D and 79,166 kg with PW4000, and sets standard capacity at 243 single-class seats. In two classes the typical layout was 220 seats, 20 business and 200 economy, with an exit limit of 275 passengers.

The date of the first revenue service varies by source: Wikipedia places it in 1986 with Swissair, while aircraftinvestigation gives December 1985 with Swissair and JT9D-7R4E engines, and March 1986 with Air India and CF6-80C2 engines, consistent with the certification dates of the A310-322 and A310-304. Its main users included Swissair, Delta, Royal Jordanian, Aeroflot, Interflug, Air France, Tarom, ČSA, Air India, THY, Hapag-Lloyd and Balair. East Germany's Interflug bought three A310-304s; with the 1988 delivery it became the first Eastern-bloc airline to operate an Airbus, and at the end of 1989 one of its -300s flew non-stop from Berlin to Havana, 8,360 km, a record for Airbus. According to aircraftinvestigation, around 183 examples of the -300 were built, the bulk of A310 production.

Several of the best-known A310 losses involve the -300 series: Thai Airways Flight 311 (A310-304, 31 July 1992, on approach to Kathmandu), Aeroflot Flight 593 (A310-304, 23 March 1994, in Siberia, after the pilot let his son sit at the controls), TAROM Flight 371 (A310-324, 31 March 1995, near Bucharest), Kenya Airways Flight 431 (30 January 2000, shortly after take-off from Abidjan), S7 Airlines Flight 778 (A310-324, 9 July 2006, at Irkutsk), Sudan Airways Flight 109 (A310-324, 10 June 2008, at Khartoum) and Yemenia Flight 626 (A310-324, 30 June 2009, in the Indian Ocean). On 12 July 2000 a Hapag-Lloyd A310-304 crashed near Vienna during an emergency landing caused by fuel exhaustion, and on 6 March 2005 an Air Transat A310-308 lost its rudder in flight to a structural failure between Cuba and Quebec City.

The -300 was the basis for the -300C combi, the -300F freighter, to which operators such as FedEx converted ex-passenger aircraft, and the military A310-300 MRT transport, in turn the basis of the MRTT tanker.