joy ride
May I suggest that consideration be given to the B.E.2c ?
Largely through the efforts of Edward Busk starting in 1912 at the R.A.F. at Farnborough on improving aircraft stability, with the unstable B.E.2a and then via the prototype R.E.1, the B.E.2c emerged as the first British ( at least) inherently stable aeroplane to enter mass production..
The lessons learned from this were applied from then on in aircraft design. Even the Tiger Moth was "basically a B.E.2c" according to Harald Penrose.
The unfortunate later reputation of the B.E.2 series in combat tends to popularly overshadow this aeroplane's significant contribution to aeronautical progress.
Noting Dave Reid's understandable comment on the Trident name. One source of illumination is A. J. Jackson's Putnam on De Havilland p.p. 422
" To ensure complete safety the powered controls are operated by three completely separate hydraulic circuits. The triplex system also extends to electrical circuits, a distinctive feature, which combined with the three engined layout, led to the adoption of Trident as an appropriate type name in September 1960."
The triplex system was designed from the start to be compatible with autoflare and later autoland - a significant step forwards technically, as Alan Lupton was suggesting.
Incidentally the first three-jet airliner concept from Vickers and BEA was the jet Vanguard of 1956, dubbed "Vanget" ( not "Trident" ).