The Russian Tri-Jet Tupolev Tu-154 made its first flight on this day in aviation history in 1968.
The prototype of the Tuplove Tu-154
The aircraft was designed as a replacement for older prop en jet aircraft in the Aeroflot fleet. There were some requirements laid down by Aeroflot that the designers of Tuplove had to consider;
A payload capacity of 35.000 - 40.000 lbs (16.000 - 18.000 kg) over a range of 1540 - 2160 nm (2800 -4000 km) while cruising at 490 kn (650 mph / 900 kph) or
A payload capacity of 13.000 lbs (5800 kg) over a range of 3100 nm - 3700 nm (5800 - 7000 km) while cruising at 460 kn (530 mph / 850 kph).
Take off distance at MTOW of 8500 ft (2600 meter)
The aircraft was designed and equipped initially with Kuzentsob NK-8-2 engines, later models were replaced with Soloviev D-30KU-154 engines. At the cost of fuel efficiency, both engine models gave the aircraft an excellent thrust to weight ratio which gave the aircraft formidable performance. Besides similarities with western jets like the Boeing 727 and the Hawker Siddeley Trident like engine configuration, S-duct air inlet for the middle engine and large wing sweep, a big difference was the wing.
While the western jet sal had a dihedral (positive V) wing, the Tu-154 (like the Tu-134) had an anhedral (negative V) wing. This gave the Tu-154 less lateral stability than its western contemporaries, it made the Tu-154 more resistant to Dutch Roll.
The aircraft had a six-wheel bogey with low-pressure tires under its wing that retracted in fairings extending from the trailing edge, this gear gave the aircraft a relatively low ground load making it possible to operate from unprepared runways.
After its first flight in 1968, the first commercial operations started in May 1971 when Aeroflot started using the aircraft for freight (mail) flights. In February 1972 passenger flights were started.
Like many aircraft designed in the 60s of the previous century it was regularly upgraded and modernised leading to an impressive list of variants;
Tu-154 42 built The initial production version production started in 1970, powered by Kuznetsov NK-8-2 Turbofans, capacity 164 pax
Tu-154A The first upgraded version, production started in 1974, powered by upgraded Kuznetsov NK-8-2u Turbofans. A centre tank was added, as well as upgraded avionics. Also, the secondary flight controls were upgraded. The MTOW was increased to 207.000 lbs (94.000 kg) 15 different cabin layouts were offered. Giving the aircraft a passenger capacity between 144 en 152 pax.
Tu-154B 111 built The first models were found to be susceptible to wing cracks so a new and stronger wing was designed. An additional fuselage wing tank was also installed as were additional tail emergency exits, The autopilot system was upgraded and certified for CAT II operations. MTOW was increased to 216.000 lbs (98.000 kg) Most of the previous models were modified to Tu-154 standard, although they had a lower MTOW than the Tu-154B, 212.000 lbs (96.000 kg)
Tu-154B-1 64 built Modified fuel, airconditioning, avionics and landing gear, capacity increased to 160 pax
Tu-154B-2 311 built (incl VIP version) By removing a galley, capacity was increased to 180 passengers Some earlier B models were modified to B-2 variant
Tu-154S 9 converted from Tu-154B All cargo version with reinforced floor and a cargo door in the left forward fuselage.
Tu-154M & Tu-154 LUX (320 built) Variant with the most upgrades compared to the initial variant. Soloviev D-30KU-154 turbofans powered this version. The triple slotted flaps were replaced by double-slotted flaps with an additional 36-degree position. With other aerodynamic, structural and system improvements the MTOW increased to 229.000 lbs (104.000 kg) Several sub-variants have been developed based on the Tu-154M - Tu-154M-LK-1, cosmonaut trainer - Tu-154MD, Chinese ELINT aircraft - Tu-154M-ON, Open skies monitoring version modified for the German Airforce
Tu-154M-100 (3 built) Upgraded with western avionics (FMS, GPS, EGPWS, TCAS, etc.) capacity 157 pax. Redesigned cabin.
Tu-155 (1 converted from Tu-154 Test aircraft for alternative fuel
Tu-164 Initial designation for the Tu-154M, never used
Tu-174 Proposed stretched variant of the Tu-154
Tu-194 A proposed shortened variant of the Tu-154
Specifications of the Tu-154B-2 and the Tu-154M