The Sukhoi T-4’s first flight took place on 22 August 1972. The T-4’s first flight was actually delayed due to forest fires that appeared around the Zhukhovskii airflield. The pilot was Vladimir Ilyushin and lasted for 40 minutes with the landing gear down (whichc stayed down for the next 5 flights of the aircraft). Here’s a video clip of the first flight and some of the subsequent flights.
The only problem that was encountered on this flight was heating of aft airframe section due to the engines. A steel heat shield was later added to fix this. The engines themselves performed well as did the fly-by-wire control system.
The T-4 underwent a total of 10 flights:
|5||4/19/1973||1 hr 24 mins|
|7||6/15/1973||1 hr 55 mins|
|8||6/26/1973||1 hr 16 mins|
|9||8/8/1973||1 hr 16 mins|
|10||1/22/1974||1 hr 1 min|
These flights revealed that the T-4 was easy to control on the ground. There was no tendency for the aircraft to pitch up during the takeoff run. Visibility from the cockpit was shown to be good. The T-4 handled relatively straightforward in level flight and approach and landing, with the auto-throttles and the fly-by-wire systems functioning as they should. The major issue during these flight tests was the excessive stick and rudder force needed to fly the T-4 when the backup flight control system was tested.
Construction on the second T-4 aircraft (called aircraft “102”) began in 1969 and completed in 1973. The first flight for 102 was scheduled for the 4th quarter of 1973. There were also plans for 3 more developmental aircraft. Aircraft 103 construction began in 1973 and was partially constructed by the time the T-4 was cancelled.
Stage 2 flight testing was to begin with the first aircraft (aircraft “101”) being used for system verification and high-speed performance and handling tests.
In the end, the Soviet Air Force decided to go with an improved version of the TU-22 (NATO code-named “Blinder”), which became the TU-22M (M = modified) (NATO code-named “Backfire”). It was felt that a modification of the Blinder was easier to do than to build a new aircaft. The Airforce also requested an increase in MiG-23 production.
Aircraft “101” went to the Airforce Museum as Monino in 1982 and parts of 102 went to the Moscow Aviation Institute but was eventually scrapped.
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