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 (up and down movements) of the piston during one power cycle, this power cycle being completed in one revolution of t ...

, 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 an injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All comp ...

, designed for use on ultralight aircraft, especially two seat ultralight trainers,

gyrocopter An autogyro (from Ancient Greek, Greek and , "self-turning"), also known as a ''gyroplane'', is a type of rotorcraft that uses an unpowered rotor in free autorotation to develop lift (force), lift. Forward thrust is provided independently, by an ...

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 The Hirth 2704 and 2706 are a family of in-line twin cylinder, two stroke, carburetted aircraft engines, with optional fuel injection, designed for use on ultralight aircraft and especially two seat ultralight trainers, single seat gyroco ...

and as a competitor to the

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

. 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 Product ...

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, turbine-powered aircraft, and some cars. It w ...

, 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 in-line twin cylinder, two stroke, carburetted aircraft engines, with optional fuel injection, designed for use on ultralight aircraft and especially two seat ultralight trainers, single seat gyrocopt ...

and compete with the

Rotax 503 The Rotax 503 is a , inline 2-cylinder, two-stroke aircraft engine, built by BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft.Raisner, William: ''LEAF catlog'', pages 6-105. Leading Edge Airfoils, 1995. As of 2011 the Rot ...

. 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 initially developed to allow Wanke ...

. Standard starting is

recoil start Rope start (also called pull start or ''rewind start'') is a method of starting an internal combustion engine, usually on small machines, such as lawn mowers, chainsaws, ultralight aircraft, small outboard motors and portable engine-generators. A ...

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