Sukhoi T-4

The Sukhoi T-4 was a Soviet high-speed Reconnaissance, anti-ship and strategic bomber aircraft that did not proceed beyond the prototype stage. The T-4 had intake ramps similar to the XB-70, was made largely from titanium and stainless steel, and featured a quadruple redundant fly-by-wire control system but also employed a mechanical system as a backup. Continue reading for more cool facts.

5. First Flew in 1972

Sukhoi T-4

The first T-4, designated “101”, first flew on 22 August 1972. The test pilot was Vladimir Ilyushin, son of famed aircraft designer, Sergei Ilyushin, and navigator Nikolai Alfyorov. Testing continued to 19 January 1974. The T-4 flew only ten times for a total 10 hours and 20 minutes. It is believed to have reached at least Mach 1.3 at an altitude of 12,000 meters using four Kolesov RD36-41 engines. These engines each produced 16,000 kgf (35,300 lbf or 157 kN) thrust with afterburners.

4. Nose Could Be Lowered

Sukhoi T-4

The aircraft’s Droop-nose lowered to provide visibility during takeoff and landing.

3. Hundreds of Patents and Inventions Attributed to Program

Sukhoi T-4

Development of the T-4 was fraught with difficulties and required a massive research effort to develop the technologies necessary, including the manufacturing technologies to machine and weld the materials necessary to withstand sustained Mach 3 flight. Nearly 600 patents or inventions are attributed to the program.

2. Periscope Used for Forward Viewing

Sukhoi T-4

A periscope was used for forward viewing when the nose was retracted, and could be employed at speeds of up to 600 km/h (373 mph). Drogue parachutes were used in addition to conventional wheel brakes.

1. Canceled for Many Reasons

Sukhoi T-4

The aircraft was designed to achieve speeds of up to Mach 3.0, but the program was cancelled before the full performance of the aircraft could be reached. Sometimes it was incorrectly stated that T-4 is the “aircraft 101” that set a 2,000 km circuit speed record of Mach 1.89. Another reason for cancelling the project was the VVS (Soviet Air Force) issuing the requirement for 250 T-4s. Meanwhile, several other high-ranking officers argued there was a need for more practical and supportive fighters instead of having such a huge flying titanium target in the air.