10Kh

10Kh was the designation for the initial series of Soviet Union pulse jet engine powered air-launched cruise missiles, reverse engineered from the Fieseler Fi 103 (V-1) flying bomb. cruise missiles developed in the 1950s (and cancelled in the same decade) by the OKB-51 under the leadership of Vladimir Chelomey and based on the V-1 flying bomb.

History
Reports of the German V-1 flying bomb attacks on London prompted Stalin to order a programme to develop a Soviet equivalent, that programme commencing in June 1944. Vladimir Chelomey, who had been working on pulse jet engines, was assigned to the project in October 1944 and given control of the OKB-51 design bureau following the death of famous designer N.N. Polikarpov. The programme was assisted by the recovery of a partial V-1 by Soviet forces at the Blizna test range in Poland. The initial V-1 copy was called 10Kh and later Izdeliye 10 ("Article 10"). Serial production was scheduled to commence in March 1945 with 100 per month, increasing to 450 per month later that year.

By the end of 1944 the development of the D-3 pulse engine that propelled the 10Kh was at the prototype stage and the first production 10Kh was ready on 5 February 1945. As no launching ramps had been constructed, the first test was an air launch from a Petlyakov Pe-8 heavy bomber on 20 March 1945, near Tashkent. By 25 July, 66 missiles had been launched, of which 44 transitioned to autonomous flight, 22 of these reaching the range target and 20 maintaining the required heading. A batch of improved 10Kh (Izdeliye 30) were constructed with wooden wings, and 73 more air launches were performed in December 1948. A ground-launched variant called the 10KhN was also tested in 1948, which used rocket-assisted takeoff from a ramp.

The purpose of the first tests was to determine the feasibility of dropping the 10Kh missile from an aircraft in flight and, about 100 m below the plane, ignite the pulse jet, but only six out of 22 missiles did so correctly. The second series of tests were on corrected faults in the missiles, allowing a success of 12 out of the 22 launched. The final tests were conducted to determine the precision (six of 18 missiles launched impacted the target) and effectiveness (from four missiles, three detonated successfully).

How 'Kh' got into the designation of Soviet missiles
Chelomey used the letter X (like eXperimental) of the Roman alphabet in his work designations of missiles designed by his bureau. The Roman letter X also exists in Cyrillic, however, and means (and is pronounced) 'Kh'. So the initial eXperimental designation got into the official Sovier missileers' parlance in the "Russified" pronunciation of 'Kh'.

Variants

 * 10Kh
 * The initial production version of the V-1 reverse engineered look-alike, powered by a single Chelomey D-3, reverse engineered Argus As014 engine.


 * 10Kh Izdeliye 30
 * An improved version with wooden wings.


 * 10KhN
 * A ground-launched version using rocket assisted take off gear to boost the missile up a launch ramp.


 * 14Kh
 * A further development with revised wings of several configurations and structural material, powered by a single Chelomey D-5 engine.


 * 14KhK1
 * A sub-version of the Kh14 powered by a single Chelomey D-6.


 * 15Kh
 * A ship launched version.


 * 16Kh
 * Experimental missiles using Kh10 airframes with single Chelomey D-6 engines, later tested with two Chelomey D-3 engines mounted side by side on V-configured pylons on the aft fuselage and extended tailplanes with rectangular fins and rudders at the tailplane tips.


 * 17Kh
 * A ship launched version.


 * 18Kh
 * A further development of the 10Kh series of cruise missiles.


 * A gliding bomb
 * An unpowered gliding bomb was also derived from the 10Kh featuring a twin tail similar to the 16Kh in addition to a central fin, as well as a jettisonable undercarriage.