US Army designations: AH-1E, AH-1F, AH-1P, AH-1S and TH-1S Israeli designation: Tsefa

Two-seat close support and attack helicopter.

PROGRAMME AH-1S first ordered as TOW-capable version of AH-1G in 1975; programme included conversion of earlier AH-1Gs and three-stage production of new aircraft with various degrees of upgrading; all versions designated AH-1S until March 1987, when new-build AH-1s allotted dormant UH-1 Iroquois suffixes AH-1P, AH-1E and AH-1F.


AH-1S: Formerly AH-1S(MOD); 92 AH-1Qs (early TOW-capable AH-1G) upgraded by 1979; 87 AH-1Qs upgraded in 1986 to 1988 with Textron Lycoming T53-L-703 engines, Kaman rotor blades (see AH-1P) and TOW system, but retaining original curved canopies; total includes 15 in TH-1S Night Stalker configuration for training AH-64 crews to operate night vision system and Integrated Helmet And Display Sighting System (IHADSS).
AH-1P: First batch of 100 new-production TOW Cobras (formerly called Production AH-1S), beginning with 76-22567, delivered 1977 to 1978, two becoming AH-1F prototypes; improvements include flat-plate canopy, upturned exhaust, improved Nap-Of-the-Earth (NOE) instrument panel, continental US (CONUS) navigation equipment, radar altimeter, improved communication radios, uprated engine and transmission, push/pull anti-torque control and, from 67th aircraft onwards, Kaman composite rotor blades with tapered tips.
AH-1E: Formerly Enhanced Cobra Armament System or Up-gun AH-1S; next 98 new-build aircraft, from 77-22673, with AH-1P improvements plus universal 20 mm gun turret (invariably fitted with long barrel 20 mm cannon); improved wing stores management system for 2.75 in rockets; automatic compensation for off-axis gun firing; 10 kVA alternator for increased power. Delivered 1978 to 1979.
AH-1F: Fully upgraded TOW version, previously designated Modernised AH-1S; 149 manufactured for US Army, beginning 78-23095, in 1979 to 1986, including 50 transferred to Army National Guard; also 378 AH-1Gs converted to full AH-1F standard between November 1979 and June 1982, including 41 TAH-1F trainers; improvements of AH-1P and AH-1E added, plus new fire-control system having laser rangefinder and tracker, ballistics computer, low-airspeed sensor probe, Kaiser pilot's head-up display, Doppler navigation system, IFF transponder, infrared jammer above engine, hot metal and plume infrared suppressor, closed-circuit refuelling, new secure voice communications, Kaman composite rotor blades.
Retrofits: Later modifications have included C-Nite equipment fitted to 50 US Army AH-1Fs (reduced from planned 500), Air-to-Air Stinger (ATAS) and Cobra Fleet Life Extension (C-Flex), engine air filter, redesigned swashplate, M43 nuclear/biological/chemical mask, AN/AVR-2 laser warning and improved SCAS roll modifications. C-Nite FLIR for TOW sight delivered 1990 to US Army's Aviation Battalion in South Korea. C-Flex items already completed include Nite Fix lighting, AH-1G-to-AH-1S upgrade and K-Flex driveshaft; remaining C-Flex work includes rotor improvements, improved TOW test set and radio upgrade.

UPGRADES: General Electric:

Announced in early 1994 that it was to re-engine the Turkish Army's 12 AH-1W Super-Cobra helicopters with T700-GE-401 turboshaft engines.
IAI/General Electric: Signed Memorandum of Understanding (MoU) to demonstrate the technical advantages of re-engining the Israeli Air Force (IAF) fleet of AH-1S helicopters with a version of the General Electric T700-701C turboshaft engine. This programme will include rewiring and installing capability for gunner to fire TOW by means of TV.
Korea, South: Currently upgrading its fleet of 72 AH-1S Cobra Helicopters to carry Hughes TOW-2A and Rockwell AGM-114 Hellfire anti-armour missiles.
Taman: Reported to have won contract in early 1995 to upgrade Turkish Cobra AH-1P Helicopters with Night Targeting Systems (NTS). Contract value thought to be US$12 million. Selected as systems integrator with Triton Systems (USA) as programme manager and Canadian Marconi as systems engineer to install a tactical navigation system to the Turkish Army AH-1P helicopters. Prototype installation commenced in March 1995. Final test and certification took place in October 1995. Production began in December 1995. Tactical Navigation System consists of the CMA 2012 B Doppler Navigation System (DNS), Rockwell Collins 822-0205-501 Miniaturised Avionics GPS Receiver (MAGR) and the CMA-2082A-5 Avionics Management System (AMS) as the Control Display Unit (CDU).


Versions of the Bell and Fuji Bell AH-1E/F/P/S and TH-1S are in service with the armed forces of the following countries: Bahrain (14); Israel (39); Japan (89); Jordan (24); Korea South (68); Pakistan (18); Thailand (4); Turkey (28) and USA (774).


Transmission rated at 962 kW (1,290 shp) for take-off and 845 kW (1,134 shp) continuous; Kaman composite blades, fitted from 67th AH-1P onwards, tolerate hits by 23 mm shells, have tungsten carbide bearing sleeves and outer 15 per cent of blade is tapered in chord and thickness; tailboom strengthened against 23 mm hits; airframe has infrared suppressant paint finish.


One 1,342 kW (1,800 shp) Textron Lycoming T53-L-703 turboshaft. Closed circuit refuelling on AH-1F. Fuel capacity 980 litres (259 US gallons; 216 Imp gallons). Upward-facing exhaust on AH-1E; IR suppression nozzle on AH-1F.


Flat-plate canopy has seven planes of viewing surfaces, designed to minimise glint and reduce possibility of visual detection during Nap-Of-the-Earth (NOE) flying; it also provides increased headroom for pilot. Improved instrument layout and lighting, compatible with use of night vision goggles. Improved, independently operating window/door ballistic jettison system to facilitate crew escape in emergency.


10 kVA 400 Hz AC alternator with emergency bus added to electrical system. Hydraulic system pressure 103.5 bars (1,500 lb/sq in), maximum flow rate 22.7 litres (6 US gallons; 5 Imp gallons)/min. Open reservoir. Battery driven Abex standby pump, for use in event of main hydraulic system failure, can be used for collective pitch control and for boresighting turret and TOW missile system. Improved environmental control and fire detection systems.


Standard Lightweight Avionics Equipment (SLAE) includes AN/ARC-114 FM, AN/ARC-164 UHF/AM voice com, and E-Systems (Memcor Division) AN/ARC-115 VHF/AM voice com (compatible with KY-58 single-channel secure voice system). Other avionics include AN/ASN-128 Doppler nav system in AH-1F; HSI; VSI; radar altimeter; push/pull anti-torque controls for tail rotor; co-pilot's standby magnetic compass. C-Flex upgrade includes introduction of Magnavox AN/ARC-164(V) UHF/AM, Collins AN/ARC-186 VHF/AM-FM, ITT AN/ARC-201 (SINCGARS) VHF/FM, and LaBarge AN/ARN-89B D/F.


M65 system with eight Hughes TOW missiles, disposed as two two-round clusters on each outboard underwing station. Inboard wing stations remain available for other stores. Beginning with first AH-1E, M28 (7.62/40 mm) turret in earlier HueyCobras replaced by new electrically powered General Electric universal turret, designed to accommodate 20 mm weapon and improve standoff capability, although only 20 mm M197 three-barrel cannon (with 750 rounds) mounted in this turret. Rate of fire 675 rds/min. Turret position is controlled by pilot or co-pilot/gunner through helmet sights, or by co-pilot using M65 TOW missile system's telescopic sight unit. Field of fire up to 110 to each side of aircraft, 20.5 upward and 50 downward. Also from first AH-1E, helicopter equipped with Baldwin Electronics M138 wing stores management subsystem, providing means to select and fire, singly or in groups, any one of five types of external 2.75 in rocket store. These mounted in launchers each containing 7 or 19 tubes, additional to TOW missile capability.
In addition to these installations, first AH-1F introduced fire-control subsystem which includes Kaiser head-up display for pilot, Teledyne Systems digital fire-control computer for turreted weapon and underwing rockets, omnidirectional airspeed system to improve cannon and rocket accuracy, Hughes laser rangefinder (accurate over 10,000 m; 32,800 ft), and Rockwell AN/AAS-32 automatic airborne laser tracker. Other operational equipment includes Hughes LAAT stabilised sight, GEC Avionics M-143 air data subsystem, Bendix/King AN/APX-100 solid state IFF transponder, Sanders AN/ALQ-144 infrared jammer (above engine), suppressor for infrared signature from engine hot metal and exhaust plume, and AN/APR-39 radar warning receiver.

LENGTH (m) : 16.18
HEIGHT (m) : 4.09
WING SPAN (m) : 13.41
MAX LEVEL SPEED (knots) : 123
MAX RANGE (nm) : 274
MAX RATE CLIMB (m/min) : 494