Existing AH-1G and AH-1Q Cobras were converted to AH-1S aircraft under the Improved Cobra Agility and Maneuverability Program (ICAM) and used the more powerful T53-L-703 powerplant. Initial AH-1S Cobras (AH-1S Modified) retained the 7.62mm minigun chin turret and 8 TOW missile hardpoints of the AH-1Q. An interim version (the "up-gunned" or AH-1S Production) replaced the minigun with a single M197 three-barreled cannon. A flat-panel canopy was also fitted. The final, fully modified configuration (AH-1S Modernized) added a distinctive extended exhaust nozzle and AN/AAS-32 laser tracker on the forward end of the rotor pylon fairing. All variants were officially designated AH-1S in 1987.


Data on design, manufacture and status

Design authority: Bell Helicopter Textron, Inc.

Primary manufacturer: Bell Helicopter Textron, Inc.

Parent type: Bell Model 209/AH-1 Cobra

Aircraft status: Operational


Primary flight and mechanical characteristics

VTOL type: Helicopter

Lift configuration: Single main rotor

Dedicated control device: Tail rotor

Crew required: TBA

Crew seating: Tandem

Landing gear: Skids

Layout and Dimensions

Data on aircraft size

Airframe width includes stub wings. While there is some variation among Cobra variants, most fuselage widths without stub wings are .914 m (3 ft).

Overall Dimensions
Overall Height: 4.10 m 13.5 ft
Overall Length: 16.14 m 53.0 ft
Overall Width: 13.41 m 44.0 ft
Airframe Dimensions
Airframe Length: 13.77 m 45.2 ft
Airframe Width: 3.15 m 10.3 ft
Airframe Height: 3.11 m 10.2 ft
Landing Gear Dimensions
Landing Gear Base: 3.27 m 10.7 ft
Landing Gear Track: 2.13 m 7.0 ft
Cabin Dimensions
Cabin Internal Height:  
Cabin Internal Length:  
Cabin Internal Width:  

Weights and Performance

Data on aircraft weight and flight characteristics

Max Gross Weight (ground): 4,536 kg 10,000 lb
Max Gross Weight (airborne):  
Max Take-off Weight: 4,536 kg 10,000 lb
Empty Weight: 2,862 kg 6,310 lb
Useful Load: 1,674 kg 3,690 lb
Empty Weight Fraction: 0.631
Climb Performance
Max Rate of Climb: 8 m/s 1,620 fpm
Hover Performance
Hover Ceiling IGE: 3,719 m 12,200 ft
Hover Ceiling OGE:  
Max Level Flight Speed: 237 km/h 128 kts
Never Exceed Speed: 315 km/h 170 kts
Service Ceiling: 3,780 m 12,400 ft
Range and Endurance
Max Range: 519 km 280 nm
Max Endurance:  

Engine Details

Aircraft powerplant (lift and/or propulsion)

Provided powerplant data is for uninstalled, sea level, static operations.

Number of engines: 1
Designation: Lycoming T53-L-703 turbine
Manufacturer: Lycoming Engines
Normal Ratings
Max continuous:  
Take-off / rated:  
Maximum: 1343 kW 1800 hp
OEI Ratings
OEI contingency:  
OEI continuous:  
OEI 30-second:  
OEI intermediate:  

Primary Lift Device

Data on primary lift devices such as main rotors

B540 blade for two-bladed Cobra main rotors.

Main Rotor Characteristics
Diameter: 13.40 m 43.96 ft
RPM: 324.0 rpm 324.0 rpm
Direction of Rotation: Counterclockwise
Hub Type: Flex-beam, stiff-in-plane teetering hub
Main Rotor Blade Characteristics
Blade Construction: Bonded aluminum spar and skin; nomex honeycomb core
Blade Chord: 0.686 m 2.25 ft
Blade Tip Geometry: Square-edged tips
Blade Twist: -0.175 rad -10.000 deg
Number of Blades: 2
Main Rotor Derived Characteristics
Disc Area: 141.03 m² 1518.0 ft²
Disc Loading: 32.16 kg/m² 6.588 lb/ft²
Solidity: 0.0652
Main Rotor Blade Derived Characteristics
Blade area per blade: 4.59 m² 49.5 ft²
Tip Speed: 227.33 m/s 745.8 fps

Primary Control Device

Data on primary control devices such as tail rotors

Tail Rotor Characteristics
Diameter: 2.59 m 8.50 ft
Configuration: Tractor
Direction of Rotation: Top blade aft
RPM: 1654 rpm 1654 rpm
Tail Rotor Blade Characteristics
Number of Blades: 2
Blade Construction: Bonded aluminum skin with abrasion strip
Blade Chord: 0.292 m 0.96 ft
Blade Twist:  
Tail Rotor Derived Characteristics
Disc Area: 5.27 m² 56.7 ft²
Solidity: 0.1436
Tail Rotor Blade Derived Characteristics
Tip Speed: 224.37 m/s 736.1 fps
Blade Area (per blade): 0.378 m² 4.07 ft²

Related VFS Resources

Resources related to the AH-1S Cobra, provided by the Vertical Flight Society.
Forum Proceedings
Vertiflite articles
Enter a search term in the box above.
Web files from vtol.org
Enter a search term in the box above.
Webpages from vtol.org
Enter a search term in the box above.

Related Public Resources

Resources related to the AH-1S Cobra, provided by public sources across the internet.