The SST2000 - PAIRadigm

The SST2000 PAIRadigm is a new twin-engine airplane design that eliminates many inherent faults of conventional twin-engine aircraft. Built by VSTOL Aircraft Corp., it is a twin-engine, two-place, high wing, strut-braced aircraft using aluminum tubing, a unique high-lift double-surface wing with slats, ailerons, flaps, wing struts, and fiberglass landing gear.

The new VSTOL SST2000PAIRadigm is a "re-invention of the twin-engine airplane" that is lighter, easier to control in an engine-out, and costs less to buy than any other twin-engine airplane.

The SST2000 PAIRadigm differs from conventional twin-engine airplanes because the engines are mounted on the fuselage, instead of mounting engines on the wings with tractor propellers. The fuselage engine location reduces weight, and the closeness of the engines to the fuselage centerline creates centerline thrust.

The name "PAIRadigm" comes from the word "paradigm" (pair-uh-dime) defined as an idea that serves as an example or pattern. The "PAIR" part of the name comes from the pair of engines on the new airplane.

Conventional Twin Verses the SST2000 Pairadigm

A fatal accident is four times more likely to occur after an engine stoppage with conventional twin-engine configurations than on a single-engine airplane, according to a 1979 National Transportation Safety Board study (AAS-79-02). An engine stoppage is critical any time, but especially so during take-off, at low altitudes, or with a heavily-loaded aircraft in high temperature, humidity, and altitude conditions.

After an engine stoppage, the pilot must significantly increase power on the working engine. Increased drag from the stopped propeller combined with the engine/propeller torque of the working engine creates a very strong yawing tendency towards the stopped or "dead" engine.

To maintain directional control, the pilot may have to apply fairly large amounts of aileron and rudder control input. If the airspeed decays below a certain value, the asymmetrical power yawing tendency will increase to the point where it can roll the aircraft into an unusual attitude. The pilot cannot recover unless he has lots of altitude and regains airspeed. Conventional twin-engine pilots receive much training to recognize and deal with these critical conditions.

The engine location on the SST2000 PAIRadigm means there is little yaw caused by an engine failure, so single-engine controllability ceases to be a problem! This alone makes the SST2000 PAIRadigm much safer to fly than most conventional twin-engine airplanes.

The new design also uses a high-lift wing that results in slow stall speeds, and low takeoff and landing rolls for further safety.

Construction Data for the VSTOL Pairadigm • Photos

Fuselage: Fiberglass covered4130 steel and aluminum tube structure using, channel, angle and, plate, the alloys used are 6061-T6, 6005-T5, 2024-T3, 7075-T6, 4130.

Wing: Slated leading edge, aluminum tube spars, 2 1/2" front spar/ 2" rear spar, 1 1/4 compression struts, with slotted ailerons. Wing has aluminum ribs with dope and fabric cover.

Tail group: 4130 steel tubing, strut braced, dope and fabric covered.

Control system:

• Elevator push/pull tube to side control stick.
• Rudder stainless steel cable to rudder petals.
• Aileron push/pull tubes to side control stick.
• Flaps lever controlled push-pull tube.
• Pitch trim manual wheel.
• Main wheels: 6" aluminum.
• Nose wheel: 6" steerable with rudder petals.
• Standard Engines: Hirth Fuel injected 2706 65 hp
  
  

Why are the engines positioned this way?

Six reasons why the Pairadigm is a better and safer aircraft.