Bell HC412PE ~ Hovercontrol

The 412 family is a development of the 212, the major change being an advanced smaller diameter four blade main rotor in place of the 212's two blade unit.

Development of the 412 began in the late 1970s and two 212s were converted to the new standard to act as development aircraft for the program. The first of these flew in August 1979, and the 412 was awarded VFR certification in January 1981. That same month the first delivery occurred. Subsequent development led to the 412SP, or Special Performance, with increased fuel capacity, higher takeoff weight and more optional seating arrangements. The 412HP, or High Performance, superseded the 412SP in production in 1991. Features include improved transmission for better hovering performance.

The current standard production model is the 412EP, or Enhanced Performance. The 412EP features a PT6T3D engine and a dual digital automatic flight control system fitted as standard, with optional EFIS displays. Fixed tricycle landing gear is optional.

Meanwhile in Indonesia, IPTN has a licence to build the 412SP, which it calls the NBell412. IPTN has a licence to build up to 100 NBell412s.

Like the 212, the 412 is in widespread use for a number of utility roles, including EMS and oil rig support, its twin engine configuration being an asset, particularly in the latter role. It too is in military service, Canada once again being a major customer (including 100 recently delivered 412EP based CH-146 Griffons).

 

 

 

Bell 407 ~ Hovercontrol

Bell's already popular 407 is the long awaited successor to its JetRanger and LongRanger light singles.

Development work on Bell's New Light Aircraft replacement for the LongRanger and JetRanger dates back to 1993. The end result was the 407, an evolutionary development of the LongRanger.

A modified 206L3 LongRanger served as the concept demonstrator 407 and first flew in this form on April 21 1994, while the 407 was first publicly announced at the Las Vegas HeliExpo in January 1995.

The 407 concept demonstrator mated the LongRanger's fuselage with the tail boom and dynamic system of the military OH58D Kiowa (which has a four blade main rotor). Fake fairings were used to simulate the wider fuselage being developed for the production standard 407. The first preproduction 407 flew in June 1995, the first production 407 flew in November 1995. Customer deliveries commenced the following February.

Compared with the LongRanger, the 407 features the four blade main rotor developed for the OH58, which uses composite construction, and the blades and hub have no life limits. Benefits of the four blade main rotor include improved performance and better ride comfort.

Another big change over the LongRanger is the 18cm (8in) wider cabin, increasing internal cabin width and space, plus 35% larger main cabin windows. Power is from a more powerful Allison 250C47 turboshaft fitted with FADEC, allowing an increase in max takeoff weight and improving performance at hotter temperatures and/or higher altitudes. The tail boom is made from carbonfibre composites, while Bell has studied fitting the 407 with a shrouded tail rotor.

Bell looked at the 407T twin 407 for a time, but opted instead to develop the substantially revised twin PW206D powered 427.

 

McDonnell Douglas 500E ~ Hovercontrol

One of the world's most successful and useful light turbine helicopters, the Hughes/McDonnell Douglas/MD Helicopters 500 series began life in response to a US Army requirement for a light observation helicopter.

Hughes won the US Army observation helicopter contest against competition from Bell and Hiller with its Allison 250 powered YOH-6A Cayuse, which first flew in February 1963. By then Hughes was already working on a civil variant, to be marketed as the Hughes 500. However, the engineering and certification designation for all military and civil variants of this helicopter type is Hughes Model 369. It was offered in basic five and seven seat configurations, and a 500U utility version. The 500 and 500U were powered by an Allison 250-C18A engine.

In 1970 the 500C followed with a more powerful 250-C20 turboshaft. From 1976 deliveries were of the 500D, an improved version with again a more powerful engine, the 250-C20B, a T-tail, and new five blade main and optional four blade tail rotors. The 500D was followed by the 500E from 1982 with recontoured nose and various interior improvements including greater head and leg room. The 530F (first delivery January 1984) is a more powerful version optimised for hot and high work.

McDonnell Douglas acquired Hughes Helicopters in January 1984, and in August 1985 the Hughes name disappeared. From then on the 500E and 530F were built as the MD-500E and MD-530F Lifter. After the 1997 merger with Boeing, the line was up for sale. Bell's plans to acquire the Boeing civil helicopter lines were thwarted by the US Federal Trade Commission (FTC) in 1998. Then in January 1999 Boeing announced the sale of the light helicopter lines to MD Helicopters, a newly formed division of Netherlands based RDM Holdings. The sale was finalised in february 1999. In April 2000 MD Helicopters contracted Kaman to build the fuselages for the single engine MDs.

Military variants are marketed under the MD-500 Defender name.

License production was undertaken in Argentina by RACA, in Italy by BredaNardi (later merged with Agusta), in Japan by Kawasaki, and in South Korea by Korean Air.