Tupolev Tu-114PLO

The Tu-114 answered an August 1955 Council of Ministers directive asking Tupolev for an airliner of 8,000 km range built on a bomber. It was, by origin, an airliner with military roots: the Tupolev design bureau derived it from the Tu-95 strategic bomber, keeping its wing, empennage, landing gear and four Kuznetsov NK-12 turboprops under a new pressurised fuselage of much larger diameter. At 10,900 km it was the longest-ranged airliner of its day, and that combination of endurance, size and bomber ancestry explains why the bureau explored a whole family of military derivatives on its airframe: the Tu-114B and Tu-114C with a dorsal radome and cruise missiles, the Tu-114E and Tu-114F reconnaissance versions, the Tu-115 military transport and the Tu-126 airborne early warning aircraft.

The Tu-114PLO was the most ambitious of them all. The letters PLO stand in Russian for anti-submarine defence, and Russian sources define it as a project to convert the Tu-114 into an anti-submarine aircraft with a nuclear power plant. The Russian Wikipedia files it among Soviet nuclear-powered aircraft projects, and GlobalSecurity likewise describes it as a retrofit project for existing Tu-114 aircraft, that is, a conversion of airline airframes rather than a clean-sheet design.

Compared with the airliner, the Tu-114PLO would have changed its role and its propulsion completely. English-language sources present it as a maritime strike variant, armed with anti-ship missiles and fitted with a naval search-and-tracking radar to locate its targets, while the Russian ones stress the anti-submarine mission; both descriptions are consistent with a long-range maritime patrol aircraft able to detect and attack ships and submarines.

The second and decisive difference was the powerplant: all sources agree the aircraft was to be nuclear-powered, which in theory would have given it practically unlimited endurance on station over the ocean. None of them details the type of reactor, how its energy was to be transmitted to the propellers or the shielding planned for the crew: the project never reached the level of definition needed to settle those parameters.

The Tu-114PLO was never built. Military Factory sums up the outcome plainly: the complexity of the whole meant the design was not taken beyond concept work. The Spanish Wikipedia dismisses it with the same conclusion, the project did not go ahead, and the Russian sources keep it in the column of projects, with no prototype and no conversion of any kind.

Of the Tu-114's family of military derivatives, the only ones that flew were the Tu-116, two Tu-95 bombers fitted with a pressurised passenger cabin, and the Tu-126 airborne early warning aircraft, of which the Russian Wikipedia counts one prototype and eight production aircraft, while Military Factory puts the total at 12. The armed projects on the passenger airframe, the PLO among them, stayed on paper, and the Tu-114 went down in history as a civil aircraft, having carried more than six million passengers for Aeroflot and Japan Airlines before the Il-62 replaced it.