Filper Research Beta

In 1958, at his company, the Copperfield Corporation, former Lockheed engineer William F. Orr began work on the "Gyroflex" system of rotor stabilization for a tandem helicopter. After flying a one/fifth-scale model, he continued development on the novel rigid rotor system that used special sinkers at the base of the blades to provide stability.[1]

In 1965, the Filper Corporation acquired rights to the Copperfield Corporation as well as the Gyroflex system, providing Orr with stable funding to continue development of the concept. Orr continued his work with J. Ford Johnston as chief engineer, J. Eric Rhodes, chief project engineer, and Irv Culver and John Turner as assistants.[2] The Filper Helicopter (N9712C) was developed as a proof-of-concept testbed that led to the Filper Beta 100A, a tandem rotor design with a two-seat cabin and pylon at the rear, and the engine with the forward pylon in front.[3] This unique arrangement resulted in the pilot and passenger being located at the rear of the helicopter. The fuselage was highly streamlined and the addition of retractable tricycle landing gear allowed for a low drag design.[4]

The Filper helicopter incorporated many innovative features, including a conventional control wheel instead of the typical helicopter flight controls, and plush seating in an effort to project the light helicopter as simple and easy to fly. The advantages of a tandem rotor included low noise levels, improved performance compared to other rotor systems and greater stability.[1] The design was intended to ease the transition from fixed-wing to rotor aircraft.[5]

This design concept was first tested in a tubular frame test rig that had two pylons with rotors connected by a drive shaft with the engine also located at the extreme front. The single pilot sat at the rear of the open structure.[1]

The Beta 100A led to a larger 200A variant (N5000F) that first flew on May 26, 1966, that was intended for commercial use. offered at $20,000 USD.[6] Filper company began production of 32 variants with an anticipated delivery date of 1967. The 200A was followed by a turbine-engined 300 variant as well as a four-seat, stretched Model 400A and 600A. The first Beta 400A (N5003F) with a fuselage stretched by 36 inches, flew on July 13, 1967.[7]

The three completed prototypes, Filper Helicopter (N9712C), Filper Beta 200A (N5000F) and Filper Beta 400A (N5003F) began a testing regime at Livermore Municipal Airport, Livermore, California. All three helicopters crashed, with a fatal accident taking place on November 7, 1967 that occurred when a rotor failed during a high-speed test. The test pilot on loan from North American Aviation died in the crash while another test pilot was injured in a second accident.[8]

Only three or four of the 32 commercial versions were ever completed, with none of them receiving certification from the Federal Aviation Administration.[9] [Note 1] A further development, the Beta 600A, was cancelled and the helicopter production line was subsequently shut down in 1969. The Filper Research division terminated in the same year with the company concentrating on its manufacture of peach-pitting machinery and its canning operations. The Filper company was absorbed in a buy-out by DiGiorgio Corporation in 1976.[10][11]

Filper Helicopter (N9712C)

Two-seat prototype with a 210 hp Continental !O-360E engine, one built and flown for evaluation and testing.

Fliper test rig

Single-seat. open tubular frame "proof-of-concept" test rig, one built and test flown.

Filper Beta 200A (N5000F)

Two-seat prototype with a 210 hp Continental IO-360E engine, one built and test flown and intended as a pattern design for commercial production.

Filper Beta 300

Prototype six-seat version powered by a 317 shp Allison 250-C18 turbine engine; not built.

Filper Beta 400A (N5003F)

Four-seat prototype with a 250 hp Continental IO-520 engine, one built and test flown and intended as a pattern design for commercial production.

Filper Beta 600A

Four-seat, projected advanced 400A variant with a 250 hp Continental IO-520 engine; not built.

Data from [9][1][7]

General characteristics

• Crew: two
• Capacity: two (three-blade rotor)
• Length: 17 ft 6 in (5.334 m)
• Main rotor diameter: 2× 20 ft 5 in (6.22 m)
• Height: 9 ft 2 in (2.8 m)
• Empty weight: 1,000 lb (453.592 kg)
• Gross weight: 1,700 lb (771.107 kg)
• Powerplant: 1 × 210 hp Continental IO-360E piston engine, 200 hp (147.1 kW)

Performance

• Maximum speed: 150 mph (241.402 km/h)
• Range: 400 miles (642 km)

• Filper Beta 200 1966 history
• Filper Beta 400 1967 history
• Filper Beta 200 history