Choppy Homebuilt Helicopter

HOBBY HELICOPTER
—Construction Plans—

The Adams-Wilson Choppy single-seat helicopter is undoubtedly the best known and most popular homebuilt helicopter ever developed.

Also known as the Flying Triumph or Hobbycopter, this design was the inspiration for a number of other successful homebuilts, including the Scorpion-I, the A/W-95, and the Skytwister.

Our Choppy Construction Plans details the construction of all parts of this affordable homebuilt helicopter.

CHOPPY DESCRIPTION

CONFIGURATION: Single seat. Two-bladed single main rotor. Anti-torque tail rotor. Bolted aluminum-tube airframe. CONTROL: Main rotor: full cyclic and collective pitch, incorporating a swash plate system. Tail rotor pitch: bellcrank operated. Autorotation accomplished by manual-disengagement lever at cyclic stick. POWER PLANT (Prototype): Triumph motorcycle engine rated at 52 hp., 650cc, vertical twin cylinder O.H.V., magneto ignition, dry sump lubrication, kick lever starting, fuel 100 octane, fuel consumption approximately 4.2 gals. (U.S.) per hour at sea level. Virtually any aircraft, motorcycle, marine, etc. engine of 450cc to 1100cc, or 45 hp or more may be substituted.

NOW AVAILABLE: Quality Rotor Blades for the Choppy

CHOPPY SPECIFICATIONS

Height............................................................... 6 ft
Length............................................................ 15 ft
Empty Weight...................................... 300+ lbs*
Gross Weight ...................................... 600 lbs**
Payload Weight ...................................... 300 lbs
Main Rotor Diameter .............................. 21½ ft
Tail Rotor Diameter ................................... 3½ ft
Power Loading (lbs/h.p.) ............................. 11.5
Disc Loading (lbs/sq ft) ................................. 1.8
Maximum Speed ..................................... 85 mph
Cruise Speed ........................................... 65 mph
Rate Of Climb ....................................... 950 fpm
Maximum Altitude ................................. 8500 ft

*Please note: when powered by a lightweight two-cycle engine, the Choppy may have an empty weight of under 254 pounds and qualify as a license-free ultralight aircraft. **The Gross Weight may be increased when more powerful engines are used.

Complete CHOPPY Construction Plans

The large 11” X 17” Construction Manual provides
full details for building this affordable aircraft.

Only $48 (add $9 post U.S., $24 foreign)

TWO FREE BONUSES COME WITH YOUR PURCHASE
As FREE special bonuses, your Choppy Construction Manual comes with
the Homebuilt Helicopter Guidebook and the full-color Vortech Catalog!

The Homebuilt Helicopter Guidebook covers, with clear, illustrated explanations, how helicopters work, the various considerations that go into their design, main- and tailrotor aerodynamics, control-system operation, a glossary of terms, and much more!

Fully illustrated with photos and detailed specifications, the Guidebook presents various popular homebuilt designs. Also included is a section on mini jet helicopters and the engines that power them (ramjet and pulsejet), plus a list of sources of parts and materials to build the Choppy, or to build or restore most any other small helicopter. The list includes sources of engines, metals, AN hardware, cables, controls, rotorblades, instruments, etc. Your copy of this fascinating and highly informative Guidebook, presenting the world of small homebuilt and kit helicopters, is included at no extra cost with your order for the Choppy Construction Manual!

Along with the Homebuilt Helicopter Guidebook, your order for the Choppy Manual also includes a FREE copy of our full-color catalog, The Vortech Flyer. A wide variety of plans are offered in the Catalog for building helicopters (piston- and jet-powered) and gyroplanes, along with sources of parts, materials, rotor blades, books, and other items of interest to the hobbyist.

HOW TO ORDER