the cargo capacity by two LD3 containers. The variant was certified on 26 April 1979. A300-600 The A300-600, officially designated as the A300B4-600, was slightly longer than the A300B2 and A300B4 variants and had an increased interior space from using a similar rear fuselage to the Airbus A310, this allowed it to have two additional rows of seats. It was initially powered by Pratt & Whitney JT9D-7R4H1 engines, but was later fitted with General Electric CF6-80C2 engines, with Pratt & Whitney PW4056 or PW4058 engines being introduced in 1986. Other changes include an improved wing featuring a recambered trailing edge, the incorporation of simpler single-slotted Fowler flaps, the deletion of slat fences, and the removal of the outboard ailerons after they were deemed unnecessary on the A310. The variant made its first flight on 8 July 1983, was certified on 9 March 1984, and entered service in June 1984 with Saudi Arabian Airlines. A total of 313 A300-600s (all versions) have been sold. The A300-600 uses the A310 cockpits, featuring digital technology and electronic displays, eliminating the need for a flight engineer. The FAA issues a single type rating which allows operation of both the A310 and A300-600. A300-600: (Official designation: A300B4-600) The baseline model of the −600 series. A300-620C: (Official designation: A300C4-620) A convertible-freighter version. Four delivered between 1984 and 1985. A300-600F: (Official designation: A300F4-600) The freighter version of the baseline −600. A300-600R: (Official designation: A300B4-600R) The increased-range −600, achieved by an additional trim fuel tank in the tail. First delivery in 1988 to American Airlines; all A300s built since 1989 (freighters included) are −600Rs. Japan Air System (later merged into Japan Airlines) took delivery of the last new-built passenger A300, an A300-622R, in November 2002. A300-600RC: (Official designation: A300C4-600R) The convertible-freighter version of the -600R. Two were delivered in 1999. A300-600RF: (Official designation: A300F4-600R) The freighter version of the −600R. All A300s delivered between November 2002 and 12 July 2007 (last ever A300 delivery) were A300-600RFs. A300B10 (A310) Airbus had demand for an aircraft smaller than the A300. On 7 July 1978, the A310 (initially the A300B10) was launched with orders from Swissair and Lufthansa. On 3 April 1982, the first prototype conducted its maiden flight and it received its type certification on 11 March 1983. Keeping the same eight-abreast cross-section, the A310 is shorter than the initial A300 variants, and has a smaller wing, down from .