Developed in 1948, under the U.S. Army the Seibel S4A was designated the YH-24 Skyhawk.  

Overview

Data on design, manufacture and status

Design authority: Seibel Helicopter Company

Primary manufacturer: Seibel Helicopter Company

Parent type: No type defined

Aircraft status: No longer flying

Configuration

Primary flight and mechanical characteristics

VTOL type: Helicopter

Lift configuration: Single main rotor

Dedicated control device: Tail rotor

Crew required: 1-2

Crew seating: Tandem

Landing gear: Wheels (non-retractable)

Layout and Dimensions

Data on aircraft size

Overall Dimensions
Overall Height:  
Overall Length:  
Overall Width: 8.84 m 29.0 ft
Airframe Dimensions
Airframe Length:  
Airframe Width:  
Airframe Height:  
Landing Gear Dimensions
Landing Gear Base:  
Landing Gear Track:  
Cabin Dimensions
Cabin Internal Height:  
Cabin Internal Length:  
Cabin Internal Width:  

Weights and Performance

Data on aircraft weight and flight characteristics

Cruise Speed: 65 mph (104.607 km/h)

Weights
Max Gross Weight (ground): 680 kg 1,500 lb
Max Gross Weight (airborne):  
Max Take-off Weight: 680 kg 1,500 lb
Empty Weight: 435 kg 960 lb
Useful Load: 245 kg 540 lb
Empty Weight Fraction: 0.640
Climb Performance
Max Rate of Climb: 4 m/s 700 fpm
Hover Performance
Hover Ceiling IGE:  
Hover Ceiling OGE:  
Limitations
Max Level Flight Speed:  
Never Exceed Speed:  
Service Ceiling: 3,170 m 10,400 ft
Range and Endurance
Max Range: 185 km 100 nm
Max Endurance:  

Engine Details

Aircraft powerplant (lift and/or propulsion)

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

Powerplant
Number of engines: 1
Designation: Lycoming O-290-D reciprocating
Manufacturer: Lycoming Engines
Normal Ratings
Max continuous:  
Take-off / rated: 93 kW 125 hp
Intermediate:  
Maximum:  
OEI Ratings
OEI contingency:  
OEI continuous:  
OEI 30-second:  
OEI intermediate:  

Primary Lift Device

Data on primary lift devices such as main rotors

Main Rotor Characteristics
Diameter: 8.84 m 29.00 ft
RPM:  
Direction of Rotation: Unknown
Hub Type:
Main Rotor Blade Characteristics
Blade Construction:
Blade Chord:  
Blade Tip Geometry:
Blade Twist:  
Number of Blades: 2
Main Rotor Derived Characteristics
Disc Area: 61.36 m² 660.5 ft²
Disc Loading: 11.09 kg/m² 2.271 lb/ft²
Solidity:  
Main Rotor Blade Derived Characteristics
Blade area per blade:  
Tip Speed:  

Primary Control Device

Data on primary control devices such as tail rotors

Tail Rotor Characteristics
Diameter:  
Configuration: Unknown
Direction of Rotation: Unknown
RPM:  
Tail Rotor Blade Characteristics
Number of Blades: 2
Blade Construction:  
Blade Chord:  
Blade Twist:  
Tail Rotor Derived Characteristics
Disc Area:  
Solidity:  
Tail Rotor Blade Derived Characteristics
Tip Speed:  
Blade Area (per blade):  

Related VFS Resources

Resources related to the S4A (YH-24 Skyhawk), 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 S4A (YH-24 Skyhawk), provided by public sources across the internet.

Images