Vertipedia - Bell Model 61/HSL-1

A longitudinal tandem rotor helicopter developed for the U.S. Navy as an Anti-submarine Warfare (ASW) hunter-killer. The aircraft is equipped with folding rotors for storage and transportation.

Overview

Data on design, manufacture and status

Design authority: Bell Aircraft Corporation

Primary manufacturer: Bell Aircraft Corporation

Parent type: No type defined

Aircraft status: No longer flying

Configuration

Primary flight and mechanical characteristics

VTOL type: Helicopter

Lift devices: 2 in Tandem (Fore/aft) configuration

Crew required: 4 in Tandem arrangement

Landing gear: Wheels (non-retractable)

Key Characteristics

Data on key physical features

Aircraft Details

Data on aircraft configuration, weights, flight performance and equipment

Layout and Dimensions

Weights and Performance

Engine Details

Primary Lift Device

Overall Dimensions
Overall Height:	4.42 m	14.5 ft
Overall Length:	27.14 m	89.0 ft
Overall Width:	15.70 m	51.5 ft

Airframe Dimensions
Airframe Length:	12.19 m	40.0 ft
Airframe Width:	3.57 m	11.7 ft
Airframe Height:	4.42 m	14.5 ft

Landing Gear Dimensions
Landing Gear Base:	4.71 m	15.5 ft
Landing Gear Track:	3.37 m	11.0 ft

Cabin Dimensions
Cabin Internal Height:
Cabin Internal Length:
Cabin Internal Width:

Cruise Speed: 100 mph (160.934 km/h)

Weights
Max Gross Weight (ground):	7,620 kg	16,800 lb
Max Gross Weight (airborne):
Max Take-off Weight:	7,620 kg	16,800 lb
Empty Weight:	5,648 kg	12,451 lb

Climb Performance
Max Rate of Climb:	8 m/s	1,475 fpm

Hover Performance
Hover Ceiling IGE:
Hover Ceiling OGE:	3,018 m	9,900 ft

Limitations
Max Level Flight Speed:
Never Exceed Speed:	185 km/h	100 kts
Service Ceiling:	4,389 m	14,400 ft

Range and Endurance
Max Range:	556 km	300 nm
Max Endurance:	3 hrs

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

Powerplant
Number of engines:	1
Designation:	P&W R-2800-50 reciprocating
Manufacturer:	Pratt & Whitney

Normal Ratings
Max continuous:
Take-off / rated:	1417 kW	1899 hp
Intermediate:
Maximum:

OEI Ratings
OEI contingency:
OEI continuous:
OEI 30-second:
OEI intermediate:

Airfoil sections: NACA 001815 at root, NACA 00099 at tip Fwd rotor rotates clockwise (viewed from top), aft rotor anti-clockwise

Main Rotor Characteristics
Diameter:	15.70 m	51.50 ft
RPM:	289.3 rpm	289.3 rpm
Direction of Rotation:	Counter-rotating
Hub Type:	Teetering with flapping stops

Main Rotor Blade Characteristics
Blade Construction:	Laminated wood with fiberglass cloth covering and stainless steel erosion strip on leading edge
Blade Chord:	0.686 m	2.25 ft
Blade Tip Geometry:	Conventional
Blade Twist:	-0.105 rad	-6.000 deg
Number of Blades:	2

Main Rotor Derived Characteristics
Disc Area:	193.52 m²	2083.1 ft²
Disc Loading:	19.69 kg/m²	4.033 lb/ft²
Solidity:	0.0556

Main Rotor Blade Derived Characteristics
Blade area per blade:	5.38 m²	57.9 ft²
Tip Speed:	237.74 m/s	780.0 fps

Tail Rotor Characteristics
Diameter:
Configuration:	Unknown
Direction of Rotation:	Unknown
RPM:

Tail Rotor Blade Characteristics
Number of Blades:
Blade Construction:	N/A
Blade Chord:
Blade Twist:

Tail Rotor Derived Characteristics
Disc Area:
Solidity:

Tail Rotor Blade Derived Characteristics
Tip Speed:
Blade Area (per blade):

References

References and sources used

Flight Handbook Navy Model HSL-1 Helicopter

Published under Authority of the Secretary of the Air Force and the Chief of the Bureau of Aeronautics
AN 01-110HCA-1, 01 May 1956 (page 75)
Report or Technical Manual

Handbook Maintenance Instructions Navy Model HSL-1 Helicopter

Published under Authority of the Air Force and the Chief of the Bureau of Aeronautics
AN 01-110HCA-2, 1956 (page 3)
Report or Technical Manual

Helicopters from "A to Z" | Part I

Ralph P. Alex
AHS Newsletter, 1961, October, 1961 (page 8)
Periodical

The Forgotten Bell HSL: U.S. Navy's First All-Weather Anti-Submarine Warfare Helicopter

Thomason, Tommy H.
Steve Ginter Publishing, 2005 (page 2)
Book