Hobby Craft Plastic Model Kit Piasecki/Vertol H-21C Workhorse — 1:72

Manufacturer and kit history

Hobbycraft was a Canadian model-kit company whose range included numerous American military aircraft and helicopters. HC2302 is an older tooling and is now principally encountered through the vintage and second-hand model-kit market.

The kit is recorded as having appeared around 1991, and contemporary collector databases identify it as Hobbycraft HC2302, H21-C Vertol Workhorse, 1:72.

The subject is particularly attractive to helicopter modellers because the H-21's tandem-rotor arrangement and unusually curved fuselage make it immediately recognisable even in the small 1:72 scale.
Kit contents

The HC2302 provides the components necessary to build a single H-21C Workhorse.

The kit includes the principal assemblies for:

Tandem-rotor fuselage

Cockpit and crew compartment

Interior/cargo cabin

Two three-bladed rotor systems

Rotor heads and shafts

Wright radial engine installation

Engine and transmission components

Landing gear

Fuselage access doors

Cabin windows

Tail and rear fuselage details

External stores/equipment appropriate to the version

Clear parts

Decals

Assembly instructions

The vintage tooling uses conventional injection moulding and is considerably simpler than many modern 1:72 helicopter kits. Surviving examples are frequently sold as complete, unstarted kits, although condition varies substantially. Current secondary-market listings show both sealed and opened HC2302 examples.
The full-size Piasecki/Vertol H-21

The H-21 Workhorse was an American tandem-rotor transport and utility helicopter developed by Piasecki Helicopter Corporation.

The design evolved from Piasecki's earlier HRP Rescuer family. The prototype XH-21 first flew on 11 April 1952, establishing the basic configuration that would become the H-21 series.

The tandem-rotor arrangement eliminated the need for a conventional tail rotor. One engine drove both rotors, which rotated in opposite directions to cancel torque.

The aircraft's strongly curved fuselage resulted in the famous “Flying Banana” nickname.
Why the H-21 was developed

The original requirement was particularly demanding: the U.S. Air Force wanted a helicopter capable of operating in the Arctic for search-and-rescue and logistical duties.

The H-21 incorporated equipment and design features intended for severe cold-weather operation. Early aircraft were used to support remote installations, including the Distant Early Warning (DEW) Line.

The aircraft consequently became both a transport helicopter and a search-and-rescue machine.
H-21A and H-21B

The first production versions were the H-21A Workhorse and H-21B Workhorse.

The H-21A used a Wright R-1820-103 radial engine producing around 1,250 hp in its standard installation.

The H-21B introduced a more powerful version of the Wright engine, rated at approximately 1,425 hp, along with improvements including additional fuel capacity, limited armour protection and an increased troop-carrying capability.

The H-21B could carry approximately 20 fully equipped troops, making it considerably more useful as an assault and transport helicopter.
H-21C Shawnee

The H-21C was the U.S. Army version.

It retained the basic H-21B configuration but incorporated Army-specific changes, most notably a substantial ventral sling hook capable of carrying an external load of approximately 4,000 lb / 1,814 kg.

Production of the H-21C began in the mid-1950s. Sources give somewhat different production totals depending on how variants and conversions are counted, but the U.S. Army alone procured 334 H-21C aircraft, with production running into the late 1950s.

In 1962, the U.S. military redesignated the H-21C as the CH-21C.
Vertol takes over

An important part of the aircraft's history is the change in manufacturer name.

Piasecki Helicopter Corporation became Vertol Aircraft Corporation in 1956.

Consequently, later H-21 aircraft are often described as Piasecki/Vertol aircraft, and the H-21C acquired the company designation Model 43.

This is why kit descriptions can use several names:

Piasecki H-21C → Vertol H-21C → CH-21C Shawnee

They refer to the same basic aircraft family, with designation changes reflecting military and corporate developments.
Performance

Representative H-21C/CH-21C specifications include:

Crew: approximately 3

Engine: 1 × Wright R-1820 radial

Power: approximately 1,425 hp

Rotor arrangement: tandem, two three-bladed rotors

Rotor diameter: approximately 44 ft / 13.4 m

Length: approximately 52 ft 7 in / 16.0 m

Maximum speed: approximately 132–140 mph

Service ceiling: approximately 19,000–20,000 ft

Range: approximately 300–450 miles depending on configuration

Troop capacity: approximately 20 troops

External load: approximately 4,000 lb / 1,814 kg on the H-21C

The exact figures differ between variants and sources. The Hill Aerospace Museum gives its CH-21C exhibit a 1,425 hp Wright R-1820, 132 mph maximum speed, 450-mile range and 19,200 ft service ceiling.
Vietnam service

The H-21 became particularly associated with the early stages of the Vietnam War.

Although originally designed as a transport and utility helicopter rather than a dedicated gunship, H-21s were used for troop transport and assault operations in Southeast Asia.

The H-21C's large cabin and tandem-rotor configuration made it capable of moving substantial numbers of troops and equipment.

The aircraft's piston engine, however, was operating in an environment very different from the cold-weather conditions for which some of the original design requirements had been established. The H-21 was subsequently replaced by newer turbine-powered helicopters as the Vietnam-era helicopter fleet developed.
International service

The H-21 had a surprisingly widespread international career.

Operators included:

France

West Germany

Canada

Sweden

Japan

Myanmar

Democratic Republic of Vietnam

United States

France was a particularly significant foreign operator. French forces obtained 108 H-21s, using them extensively during the Algerian War.

West Germany also operated H-21C aircraft, with 32 examples supplied in the late 1950s and assembled by Weserflug.
French service

French Army aviation used the H-21 extensively during operations in Algeria.

The aircraft became widely known in French service as the “Banane”, referring to its characteristic curved fuselage. French H-21s were employed in transport and assault roles during the Algerian conflict.

This international service history is one reason the H-21 remains an interesting modelling subject: the same basic airframe appeared in a variety of national colour schemes.
Post-war development

The H-21 also served as a development platform.

Two H-21C airframes were modified as XH-21D test aircraft, replacing the single piston engine with two General Electric T58 turboshaft engines.

The project demonstrated the possibilities of turbine propulsion but did not enter production.

The later turbine-powered Vertol 107 family represented a much more significant step toward the next generation of tandem-rotor helicopters.
Survivors

A number of H-21s survive in museums.

The Hill Aerospace Museum in Utah displays a Workhorse/CH-21 example, serial 56-2142. Interestingly, the aircraft began its career as an H-21B rather than a C and was subsequently redesignated and restored for museum display.

The museum records the aircraft as having entered U.S. service in 1957 and ultimately being retired in 1971 before entering the museum system.