The Trident was a jet airliner of all-metal construction with a T-tail and a low-mounted wing with a quarter-chord sweepback of 35 degrees.
It had three rear-mounted engines: two in side-fuselage pods, and the third in the fuselage tailcone, aspirating through an S-shaped duct.
One version, the 3B, had a fourth "boost" engine aspirated through a separate intake duct above the main S-duct.
All versions were powered by versions of the Rolls-Royce Spey, while the boost engine was also by Rolls-Royce: the RB.162, originally intended as a lift engine for VTOL applications.

The Trident was one of the fastest subsonic commercial airliners, regularly cruising at over 610 mph (980 km/h).
At introduction into service its standard cruise Mach Number was 0.88/ 380 kn IAS, probably the highest of any of its contemporaries.
Designed for high speed, with a critical Mach number of 0.93, the wing produced relatively limited lift at lower speeds.
This, and the aircraft's low power-to-weight ratio, called for prolonged takeoff runs.
Nevertheless, the Trident fulfilled BEA's 6,000 ft (1,800 m) field length criterion and its relatively staid airfield performance was deemed adequate before the arrival into service of the Boeing 727 and later jet airliners built to 4,500 ft (1,400 m) field length criteria.
The aerodynamics and wing was developed by a team led by Richard Clarkson, who would later take the Trident's wing design for the wing of the Airbus A300; for the Trident he won the Mullard Award in 1969.

The Trident was routinely able to descend at rates of up to 4500 ft/min (23 m/s) in regular service.
In emergency descents of up to 10,000 ft/min, it was permissible to use reverse thrust.
Below 280 kn IAS, it was also possible to extend the main landing gear for use as an airbrake.
The Trident's first version, Trident 1C, had the unusual capability of using reverse thrust prior to touchdown.
The throttles could be closed in the flare and reverse idle set to open the reverser buckets.
At pilot discretion, up to full reverse thrust could then be used prior to touchdown.
This was helpful to reduce hydroplaning and give  very short landing runs on wet or slippery runways while preserving wheel brake efficiency and keeping wheel brake temperatures low.
Brakes were fitted with the Dunlop Maxaret anti-skid system.
The Trident was a jet airliner of all-metal construction with a T-tail and a low-mounted wing with a quarter-chord sweepback of 35 degrees. It had three rear-mounted engines: two in side-fuselage pods, and the third in the fuselage tailcone, aspirating through an S-shaped duct. One version, the 3B, had a fourth "boost" engine aspirated through a separate intake duct above the main S-duct. All versions were powered by versions of the Rolls-Royce Spey, while the boost engine was also by Rolls-Royce: the RB.162, originally intended as a lift engine for VTOL applications.
The Trident was one of the fastest subsonic commercial airliners, regularly cruising at over 610 mph (980 km/h). At introduction into service its standard cruise Mach Number was 0.88/ 380 kn IAS, probably the highest of any of its contemporaries. Designed for high speed, with a critical Mach number of 0.93, the wing produced relatively limited lift at lower speeds. This, and the aircraft's low power-to-weight ratio, called for prolonged takeoff runs. Nevertheless, the Trident fulfilled BEA's 6,000 ft (1,800 m) field length criterion and its relatively staid airfield performance was deemed adequate before the arrival into service of the Boeing 727 and later jet airliners built to 4,500 ft (1,400 m) field length criteria. The aerodynamics and wing was developed by a team led by Richard Clarkson, who would later take the Trident's wing design for the wing of the Airbus A300; for the Trident he won the Mullard Award in 1969.
The Trident was routinely able to descend at rates of up to 4500 ft/min (23 m/s) in regular service. In emergency descents of up to 10,000 ft/min, it was permissible to use reverse thrust. Below 280 kn IAS, it was also possible to extend the main landing gear for use as an airbrake. The Trident's first version, Trident 1C, had the unusual capability of using reverse thrust prior to touchdown. The throttles could be closed in the flare and reverse idle set to open the reverser buckets. At pilot discretion, up to full reverse thrust could then be used prior to touchdown. This was helpful to reduce hydroplaning and give  very short landing runs on wet or slippery runways while preserving wheel brake efficiency and keeping wheel brake temperatures low. Brakes were fitted with the Dunlop Maxaret anti-skid system.
Hawker Siddeley Trident