In February 1954, the Army announced a design competition for a turbine-powered multi-purpose helicopter to be used in the Medical Corps. The requirement was for a helicopter capable of carrying a payload of 800 lb (363 kg) over a distance of 100 n.m. (185 km). It was also to be easy to maintain and loadable with the cargo aircraft of the time (e.g. the C-124 Globemaster II). The Lycoming T53 free-wheeling turbine was to be used as the engine.
Building on the experience gained with the development of the H12 cell, Bell designed the Model 204, which won the competition and was designated XH-40 by the US Army. In May 1955 Bell received the order to build three prototypes (serial numbers 55-4459 to 4461). The corresponding engineering work began in June 1955, on 28 October the mock-up could be inspected and shortly afterwards the construction of the prototypes began. Less than a year after construction began, the first flight of the first XH-40 specimen took place on 22 October 1956, followed by the other two prototypes in February and June 1957.
Under a contract dated 19 October 1956, Bell was commissioned to produce six YH-40 prototypes for operational testing. Nine pre-production machines followed, which were designated HU-1 (H for helicopter, U for utility) in the Army system valid from 1956 to 1962. The string HU-1 led to the nickname “Huey” used by GIs. Officially, the helicopter was named “Iroquois” in accordance with the practice of naming Army aircraft after Indian tribes.
On 30 June 1959, the first production HU-1A was delivered to the 101st Aviation Battalion. The 56th and 57th Medical Detachment (Helicopter Ambulance) also received their aircraft at this time to test the originally intended purpose, medical evacuation. In 1962, the designation was changed to UH-1 in the course of the standardisation of the individual systems of the Air Force, Navy and Army.
Use in the Vietnam War
The Huey became famous through its use in the Vietnam War, where it was used for almost every purpose, including close air support, although it was not actually designed for this. The loss rate was correspondingly high: of the more than 7,000 Hueys used in Vietnam, only 2,000 returned after the end of the war – although several hundred were abandoned, destroyed or handed over to the South Vietnamese army when the US troops withdrew.
Matching kit components
Kit
After Sikorsky and Tiger, the Bell 204/205 is the next model that we have prepared with sheet metal joints, rivets and screws so that we can say that we present a super scale model.
The original model was made from available documentation of Bell 204/205 helicopters. The master model parts were milled in Uriol on a large 5-axis milling machine and then prepared with all the sheet metal joints and rivet / screw replicas to create a super scale model with all the details. After that, the necessary negative moulds were created.
The production of all GRP parts takes place in 6 moulds. High-quality resin systems are used to produce high-strength, very light components, which in the end result in all parts necessary for the construction of the Bell 204/205. Some of the wooden frames in the tailboom are already resin-coated in the moulds.
A set of ribs made of high quality aircraft plywood is glued into the fuselage and takes over the mounting of the tank and the turbine or electric mechanics.
The finished model has doors that can be opened or slid as on the original.
Windows are fixed between GRP covers with superglue.
The landing gear is made of aluminium tube and is screwed to the fuselage.
The fairing of the turbine-gearbox-area is equipped with replica caps. Various air intakes on and around the fairing complete the super-scale replica.
Additional optional equipment such as cockpit, interior seating, armament etc. can be ordered separately depending on the model and make your helicopter a unique scale replica of your dream helicopter.
To optimise the weight, the model is built in CFRP / GRP sandwich and is extremely light with extreme torsional rigidity.
The tail rotor is driven by a flex shaft with sufficient dimensions for a large helicopter.
The Bell 204/205 is equipped with a rotor head from Heli-Factory which is based on the original and also has the “paddle rod”. Construction of the rotor head in full metal with damping via Delrin bushings.
The rotor head is controlled by 3 servos via a swash plate for a 15 mm rotor shaft (hollow shaft) from Heli-Factory.
The model is completely assembled by us. You can choose between:
– Model ready to be built, as an extension model with the desired 3D special parts according to your wishes.
– Model ready to fly with drive, RC, the desired 3 D special parts and the paint of your choice.
You can choose between turbine or electric motor drive.
Turbine version with Jakadowsky PRO 6000 or PRO-X
Electric version with Hacker Q 100
We mainly use radio control components from Futaba, PowerBox, Bavarian Demon, Hacker, Savöx and Jeti. The desired installation of 3 D option special parts will be considered according to your wishes.
mechanics
Mechanics HF -Bell204 for Jakadofsky turbines PRO 6000, Pro X or electric drive with Q 100.
Robust mechanics specially designed for the Bell 204 and the position of the turbine.
Sturdy GRP side plates screwed onto aluminium bolts milled from the solid form the base frame of the mechanism.
An original bevel gear set from Jakadowsky is placed between the spacer bars, which was manufactured with high precision and is driven by a main gear made of high-strength plastic. This main gear is designed for the desired speed of the rotor head for the Gazelle and is specially milled for us from the solid. This ensures 100 % concentricity. The plastic main gear then engages the pinion of the centrifugal clutch of the Jakadofsky turbine or the electric motor.
High-quality bearings complement the mechanics and allow for a long service life.
Main rotor head speed 690 rpm
Tail rotor speed 4300 rpm
Mechanics for 15 mm main rotor shafts
All parts “Made in Germany”!!!
Rotor head
Rotor head and swash plate:
The Bell 204/205 is equipped with a rotor head from Heli-Factory which is based on the original and also has the “paddle rod”. Construction of the rotor head in full metal with damping via Delrin bushings.
The rotor head is controlled by 3 servos via a swash plate for a 20 mm rotor shaft (hollow shaft) from Heli-Factory.
Manufactured on high-precision 5-axis machining centres according to our drawings and designs.
Extremely good-natured and precisely controllable rotor head with extreme attention to detail and reproduction of the scale view of the rotor head.
Blade handle holder 14 mm
Rotor head for 15 mm main rotor shafts
Rotor head completely assembled
All parts “Made in Germany”!!!
Rotor blades Bell 204/205:
Rotor blades 4 pieces finely balanced with a grip of 14 mm
length 1200 mm
Width 109 mm
Tail rotor:
The 2-blade tail rotor is completely made of aluminium with a bevel gear combination 1:1 with a diameter of 23.3 mm. The bevel gears have cyclo-palloid gearing module 0.6 and the tooth flanks are induction hardened.
This gives us sufficient strength for large models with increased torque which the tail rotor has to compensate.
The direction of rotation is designed for the Lama, but can be changed at any time by repositioning the gear wheels in the gearbox. This means that it is possible to change the direction of rotation or the side of rotation at a later date.
An 8mm hollow drilled, case hardened and ground tail rotor shaft drives the 2 blade tail rotor with steel centre piece and mounted blade holders.
Tail rotor completely manufactured in metal on high-precision 5-axis machining centres for us according to our drawings and layouts.
Blade connection 10mm
With 10mm blade holder fastening screw M4 12.9
Tail rotor completely mounted and gear backlash adjusted.
All parts “Made in Germany”!!!
Drive
A very safe way to drive the elevated tail rotor is to use a flex-shaft. Heli-Factory uses shafts from a Swiss production.
The shaft is attached between the mechanics and the tail rotor with specially developed adapters. A unique grease lubrication applied by Heli-Factory ensures operation for over 50 hours.
After the 50 hours, loosen the shaft coupling on the mechanics, pull the tail rotor with the flex inner shaft and re-grease the inner shaft. Replacement grease from Bosch can be ordered from Heli-Factory. Then push the shaft back in, degrease the shaft connection area, insert it into the coupling and tighten the coupling again and screw in the grub screws after the grub screws have been secured with screw lock.
Scale parts
Available as optional 3 D printed parts or made of aluminium:
Complete cockpit with front seats
Rear seats
Lighting with position lights incl. holders
Fixed landing light
Retractable landing light
Cabin door handles
Cable cutter
Windscreen wiper
Static rescue winch
Rescue winch with function
Searchlight with holder
Antenna set
Various types of armament, some of which can be moved by servos
Pilot manikins
