The Hirth 3202 and 3203 are a family of in-line twin cylinder,

two stroke A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a power cycle with two strokes of the piston, one up and one down, in one revolution of the crankshaft in contrast to a four-stroke engine which re ...

, carburetted aircraft engines, with optional

fuel injection Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of a fuel injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All c ...

, designed for use on

ultralight aircraft Ultralight aviation (called microlight aviation in some countries) is the flying of lightweight, 1- or 2-seat fixed-wing aircraft. Some countries differentiate between weight-shift control and Aircraft flight control system, conventional three-a ...

, especially two seat ultralight trainers,

gyrocopter An autogyro (from Greek and , "self-turning"), gyroscope, gyrocopter or gyroplane, is a class of rotorcraft that uses an unpowered rotor in free autorotation to develop lift. A gyroplane "means a rotorcraft whose rotors are not engine-driven ...

s and small homebuilts. It is manufactured by

Hirth Hirth Engines GmbH is an engine manufacturer based in Benningen, Germany. It is currently a part of the UMS Aero Group. Hirth began manufacturing aero engines in the 1920s, was taken over by Heinkel in WWII to develop the Heinkel-Hirth jet en ...

of Germany.

Development

The 3203 was developed as a replacement for the Hirth 2706 and as a competitor to the

Rotax 582 The Rotax 582 is a two-stroke cycle, two-stroke, two-cylinder, rotary intake valve, oil-in-fuel or oil injection pump, liquid-cooled, gear reduction-drive aircraft engine manufactured by Rotax, BRP-Rotax GmbH & Co. KG. It is for use in non-ce ...

. It replaced the 2706 in the Hirth line in May 2002. The engine is similar to the

Rotax Rotax is the brand name for a range of internal combustion engines developed and manufactured by the Austrian company BRP-Rotax GmbH & Co KG (until 2016 BRP-Powertrain GmbH & Co. KG), in turn owned by the Canadian Bombardier Recreational Prod ...

powerplant in being a two-cylinder in-line engine, with dual

capacitor discharge ignition Capacitor discharge ignition (CDI) or thyristor ignition is a type of automotive electronic ignition system which is widely used in outboard motors, motorcycles, lawn mowers, chainsaws, small engines, gas turbine-powered aircraft, and some cars ...

, although it is air-cooled, compared to the 582's liquid cooling. The 3202 was developed from the 3203 as a de-rated version to replace the

Hirth 2704 The Hirth 2704 and 2706 are a family of Inline engine (aviation), in-line twin cylinder, two stroke, carburetor, carburetted aircraft engines, with optional fuel injection, designed for use on ultralight aircraft and especially two seat ultral ...

and compete with the

Rotax 503 The Rotax 503 is a , inline 2-cylinder, two-stroke engine, two-stroke aircraft engine, built by Rotax, BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft.Raisner, William: ''LEAF catalog'', pp. 6-105. Leading Edge Airfoils, 1 ...

. Both engines have the same bore, stroke, displacement, compression ratio, and weight as the Hirth engines they replace. Both the 3202 and 3203 use free air or fan cooling, with dual Bing 34 mm slide carburetors or optionally fuel injection. The cylinder walls are electrochemically coated with

Nikasil Nikasil is a trademarked electrodeposited lipophilic nickel matrix silicon carbide coating for engine components, mainly piston engine cylinder liners. Development Nikasil was introduced by Mahle in 1967 and was initially developed to allow W ...

. Standard starting is

recoil start Rope start (also called ripcord , ''pull start'', or ''rewind start'') is a method of starting an internal combustion engine, usually on small machines, such as lawn mowers, chainsaws, grass trimmers, ultralight aircraft, small outboard mo ...

with electric start as an option. The reduction drive system available is the G-50 gearbox, with reduction ratios of 2.16:1, 2.29:1, 2.59:1, 3.16:1, or 3.65:1, with a cog-belt reduction drive optional. The engines run on a 50:1 pre-mix of unleaded 93 octane auto fuel and oil, or optionally oil injection.

Variants

;3202 :Twin-cylinder in-line, two stroke, aircraft engine with a dual Bing 34mm slide carburetors or fuel injection. Produces at 5500 rpm and has a factory rated TBO of 1200 hours. In production. Replaced the 2704 in production in May 2002. ;3203 :Twin-cylinder in-line, two stroke, aircraft engine with dual Bing 34mm slide carburetors or fuel injection. Produces at 6300 rpm and has a factory rated TBO of 1000 hours. In production. Replaced the 2706 in production in May 2002.

Applications

;3202 ;3203

Specifications (3203)

References

External links