In recent weeks, we have looked at several classic aircraft, including the trijet Boeing 727. However, the British competitor to this US powerhouse, the Hawker Siddeley Trident, was the first three-engined commercial jet to fly. Performing its maiden flight on January 9th, 1962, the Trident broke new ground in the aviation industry.
The legendary De Havilland Aircraft Company initially proposed the jet. However, Hawker Siddeley took over the company at the turn of the 1960s. Before this acquisition, American Airlines expressed its interest in a three-engined plane, but the carrier eventually opted for the American-made 727. Thus, De Havilland adapted its design to meet the requirements of British European Airways (BEA) and the domestic United Kingdom market.
Notably, it was this adaptation that caused the initial model of the type to suffer. It was felt that the plane lacked the range to truly compete with the 727.
Moreover, while the plane could perform well at high speeds, the Trident 1C’s wing generated less lift at low speeds when against its rivals. With this aspect, the three-member crews found that there were longer take-off rolls. Subsequently, the plane attained the nickname of “The Gripper.”
Despite these concerns, the aircraft was designed with the latest technology in mind. For instance, it pioneered the Smiths Aircraft Industries Autoland System. This feature enabled pilots to fly in effectively zero visibility conditions. This factor allowed launch customer BEA to continue operating well throughout the harsh British winters.
Altogether, the type went through several adjustments as the requirements of the industry evolved, including the shifting from DH121 to HS121 amid the change of management. The plane managed to find a balance, but with the 727 already having a stronghold, it was hard to catch up.
“Delays created by the re-organisation and the overall upheaval saw HS121 Trident lose out to the Boeing 727 on more than one occasion. Many prospective buyers decided that delivery promises were ‘commercially, too risky.’” BAE Systems shares on its website.
“Hawker Siddeley then introduced the HS121 Trident 1E which offered increased passenger capacity (115 – 139), a much increased fuel capacity with a higher take-off weight. Many observers commented that the aircraft was now much closer in specification to the original HS121 Trident 1A configuration although in the end only 15 were built, operating with Kuwait Airways, Iraqi Airways and Pakistan International. Other operators included Channel Airways, Northeast Airlines, Air Ceylon and Cyprus Airways.”
So, further enhancements were needed to grow in the market. Even BEA was looking to expand into distant regions. As a result, the HS121 Trident 1F was introduced. This plane, too, would go through a series of changes and was renamed the Trident 2E due to its extended range.
Three 11,960 lbf (53.2 kN)Rolls-Royce Spey 512 engines powered this variant, allowing for a cruise speed of 605 mph (974 km/hr). Impressively, the plane would reach a range with a maximum payload of 2,430 mi (3,766 km). In comparison, the Trident 1C’s range was 930 mi (1,497 km).
Two designs were offered with this version. The HS132 would come with 158 seats and the HS134 would provide 185. The engines were also moved to under the wings. Despite the enhancements and flexibility, airlines still generally preferred to go with Boeing, with the 737 also joining the fold.
Even BEA wanted to try out these American jets. However, UK authorities blocked the move, which forced the airline to stick with Hawker Siddeley. In another attempt to satisfy the market, the company announced the HS121 Trident 3.
BEA was then forced to return to Hawker Siddeley, which responded with a further stretched version of the basic Trident, known this time as the HS121 Trident 3. This variant had a length of 131 ft 2 in (39.98 m), outstretching its original predecessors that were 114 ft 9 in (34.98 m) long.
A key innovation with this variant was that the wings were modified to handle more weight. This move would plant the seeds of the UK’s expertise in wing tech. This is a factor that is prevalent in the country today with Airbus’ wing processes primarily handled here.
BEA wasn’t satisfied with the initial design. The carrier felt it couldn’t perform in hot and high conditions. Instead of replacing the three engines, the manufacturer opted to place an addition into the tail.
Overall, a small Rolls-Royce RB162 turbojet was implemented, adding 15% more thrust for takeoff while adding just 5% more weight. Furthermore, it would only be utilized when required. This version would be known as the Trident 3B.
Across the industry
At home, BKS/Northeast Airlines, British European Airways, British Airways (primarily inheritances), and Channel Airways operated the plane. Across the continents, Air Ceylon, CAAC Airlines, China United Airlines, Cyprus Airways, Iraqi Airways, Kuwait Airways, Pakistan International Airlines, and Air Charter Service of Zaire held the type. Military operators included China’s People’s Liberation Army Air Force and the Pakistan Air Force.
The trident was retired in 1995, and 117 units were built between 1962 and 1978. In comparison, 1,832 727s were produced, which were designed to the Trident’s original specification. Moreover, the Boeing production was in passenger service until two years ago.
BAE Systems notes five aircraft on display at museums. Trident 1C, registration G-ARPO is has been sitting at the North East Aircraft Museum in Sunderland. Trident 2E, registration G-AVFB, is at the Imperial Imperial War Museum in Cambridgeshire, Trident 3B, registration G-AWZK, can be seen at the Aviation Viewing Park in Manchester, and Trident 3B, G-AWZM is at the Science Museum in Wiltshire. Moreover, unlike the aforementioned units spotted around the UK, Trident 1E, B-2207 has been at the Military Museum of the Chinese People’s Revolution in Beijing, China.
Altogether, amid all the chops and changes, the Trident could not keep up with developments across the pond.
What are your thoughts about the Hawker Siddeley Trident? Did you ever manage to get a chance to fly the aircraft over the years? Let us know what you think of the plane and its operations in the comment section.