The Editors of the Russkiy Mir portal
The green agenda is increasingly dominating every year. In the pursuit of reducing harmful emissions, automobile corporations one after another are switching to electric cars and environmentally friendly fuel. One of the most discussed and promising trends is the replacement of traditional fuel with hydrogen. Hydrogen fuel cell cars are already running the roads, and more conservative and safety-conscious aviation is next in line. Leading aircraft manufacturers like Boeing are already experimenting with hydrogen fuel these days. However, only few people remember that the first hydrogen-powered plane was the Tupolev Tu-155.
Yep, the world's first hydrogen-powered airliner was built back in the late 1980s at the Tupolev Design Bureau. The Tu-155 was designed on the basis of the Tu-154, one of the most popular airliners in the world. The new aircraft was created as a “flying laboratory” for testing engines with cryogenic fuel.
Hydrogen (like liquefied natural gas) was given great importance at the time, because it was seen as the next-generation aviation fuel because of its low environmental impact. After all, its reserves in theory were inexhaustible, and high energy costs of production were not clearly a turn-off for the USSR.
The chief designer of the Tu-155 was Vladimir Andreev. Modification of the Tu-154 was carried out at an aircraft factory in Samara, which is now called Aviacor company. The first flight of the Tu-155 made 25 years ago, on April 18, 1988, and in January 1989 the first test flight on liquefied gas.
Totally more than a hundred test flights were made, five of them on liquid hydrogen. 14 world records were set in the course of testing.
The plane was equipped with the NK-88 engine, which ran on hydrogen fuel. The other two regular engines ran on kerosene. A fuel tank with shielded insulation (the temperature of liquid hydrogen is -259°C) was placed in the tail end of the plane. Hydrogen reserve was enough for about two hours of flight.
The Tupolev Design Bureau was planning develop TU-156 aircraft with LNG engine, but because of the collapse of the USSR it was never built. Well, the Tu-155 aircraft is still kept at the Ramenskoe airfield in Zhukovsky city in Moscow Oblast; it can be observed at Russian air shows.
In fact, the Soviet Union also tested airliners with a nuclear plant, which was to provide them with a much greater range and autonomy than conventional aircraft. Compact nuclear reactor was installed on the Tu-95LL, which made a series of test flights in the 1960s.
