Ka-25

Kamov Ka-25 'Hormone'

Above:

Ka-25 attached to the Aegir Fleet, based at Comberth harbor before its destruction. This particular aircraft operated from the deck of the Erusian cruiser Beluga on anti submarine warfare duties. It is believed to have been shot down in the intial raid by ISAF fighters.

Below:



Early photo depicting a KA-25 of the Erusian Navy, the Erusian ensignia being clearly visible on the rear most vertical stabaliser fin.

Overview
The deployment of the Polaris naval strategic nuclear missile system in the USA acted as a catalyst accelerating development of aircraft carrying ships in the USSR. The Ka-25 Hormone helicopter was developed to meet a Soviet Naval Air Force specification for an anti-submarine helicopter for ship or shore-based use. The first Ka-25 prototype flew in 1961. Designed by the world's leading pioneer of co-axial helicopters, Nikolai I. Kamov (1902-1973) this Soviet AV-MF (naval aviation) anti-submarine warfare rotary wing aircraft was assigned to the Soviet Helicopter Carrier Moskva. The Hormone is powered by twin turbines, installed side-by-side above the cabin, that drive two, three-bladed coaxial, contra-rotating rotors. The contra-rotating rotors eliminated the need for an anti-torque tail rotor, and made a very compact design possible, with obvious benefits for shipboard operations. Hormone cannot hover or dip at night.

Design and Development
In the late 1950s there was an urgent demand for anti-submarine helicopters for deployment on new ships equipped with helicopter platforms entering service with the Soviet Navy. Kamov's compact design was chosen for production in 1958. To speed the development of the new anti-submarine helicopter Kamov designed and built a prototype to prove the cabin and dynamic components layout; designated Ka-20, this demonstrator was not equipped with mission equipment, corrosion protection or shipboard operational equipment. The Ka-20 was displayed at the 1961 Tushino Aviation Day display, and given the ASCC Reporting name 'Harp'.

Definitive prototypes of the Ka-25 incorporated mission equipment, corrosion protection for the structure. The rotor system introduced aluminium alloy blades pressurised with nitrogen for crack detection, lubricated hinges, hydraulic powered controls, alcohol de-icing and automatic blade folding. Power was supplied by two free-turbine engines sat atop the cabin, with electrically de-iced inlets, plain lateral exhausts with no Infra-Red countermeasures, driving the main gearbox directly and a cooling fan for the gearbox and hydraulic oil coolers aft of the main gearbox. Construction was of stressed skin duralumin throughout with flush-riveting, as well as some bonding and honeycomb sandwich panels. The 1.5m x 1,25m x 3.94m cabin had a sliding door to port flight deck forward of the cabin and fuel tanks underfloor filled using a pressure refueling nozzle on the port side. A short boom at the rear of the cabin had a central fin and twin toed in fins at the ends of the tailplane mainly for use during auto-ration. The undercarriage consisted of two noncastoring mainwheels with sprag brakes attached to the fuselage by parallel 'V' struts with a single angled shock absorber to dissipate landing loads, and two castoring nosewheels on straight shock absorbing legs attached directly to the fuselage either side of the cockpit which folded rearwards to reduce interference with the RADAR, all wheels were fitted with emergency rapid inflation flotation collars. Flying controls all act on the co-axial rotors with pitch, roll and collective similar to a conventional single rotor helicopter. Yaw was through differential collective which has a secondary effect of torque, an automatic mixer box ensured that total lift on the rotors remained constant during yaw maneuvers, to improve handling during deck landings. Optional extras included fold up seats for 12 passengers, rescue hoist, external auxiliary fuel tanks or containers for cameras,flares,smoke floats or beacons.

Operators
Estovakia Yutobania Erusia

Featured In
Ace Combat 04: Shattered Skies

Specifications
Country of Origin: Russian Federation Builder: Kamov Role: ASW, Recce Variants: A is ASW, B is OTH targeting, C is utility / SAR Rotor Diameter: 51 ft., 8 in. / 15.7m Length: 32 ft., 3 in. / 9.8m Height: 17 ft., 7 in. / 5.4m Weight: 16,100 lbs. / 7100kg Engine: 2 x 900 shp Glushnekov GTD-3 Maximum speed: 137 mph / 220kph Cruising speed: 195kph Ceiling: 3500 meters Range: 216nm Payload: 600 kg Sensors: A: Dipping sonar; 3 sonobuoys, MAD, Mushroom radar, EO sensor estimated to be FLIR. B: Big Bulge radar, ESM data link Armament: E45-75A torp or B-1 DC. Nuclear DB; B and C are unarmed