The Hirth 2702 and 2703 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 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 conventional three-axis control aircraft with ailer ...

and especially two seat ultralight trainers, single seat

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.Cliche, Andre: ''Ultralight Aircraft Shopper's Guide'' 8th Edition, page G-3 Cybair Limited Publishing, 2001. Purdy, Don: ''AeroCrafter - Homebuilt Aircraft Sourcebook'', page 72. BAI Communications.

Development

The 2703 was developed as a competitor to 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 Ro ...

and 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 ...

. The 2702 was developed from the 2703 as a de-rated version. Both the 2702 and 2703 use free air or fan cooling, with Bing 34mm slide carburetors. 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 Wankel ...

. 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. Al ...

. Reduction drive systems available are the G-50 gearbox with reduction ratios of 2.16:1, 2.29:1, 2.59:1, 3.16:1, or 3.65:1, or a multi-element cog belt drive. A tuned exhaust and electric start are optional. The engines runs on a 50:1 pre-mix of unleaded 93 octane auto fuel and oil.

Variants

;2702 :Twin-cylinder in-line, two stroke, aircraft engine with a single Bing 34mm slide carburetor. Produces at 5500 rpm and has a factory rated TBO of 1200 hours. Still in production. ;2703 :Twin-cylinder in-line, two stroke, aircraft engine with dual or optionally a single Bing 34mm slide carburetor. Produces at 6200 rpm and has a factory rated TBO of 1000 hours. The 2703 has been largely supplanted in production by the

Hirth 3202 The Hirth 3202 and 3203 are a family of in-line twin cylinder, two stroke, carburetted aircraft engines, with optional fuel injection, designed for use on ultralight aircraft, especially two seat ultralight trainers, gyrocopters and small ...

, but in 2009 was still available as a special order from the factory.

Applications

;2702 *

Airfer Transan The Aifer Transan is a Spanish powered parachute, designed and produced by Airfer Paramotores. Design and development The aircraft was designed to comply with the Fédération Aéronautique Internationale microlight rules. It features a parac ...

* Brutsche Freedom 40 *

Flightstar The Flightstar is a large family of single and two-seat, high wing, single engined Homebuilt aircraft, kit aircraft that was produced by Flightstar Sportplanes of South Woodstock, Connecticut. In 2009 the rights, tooling and parts inventory were ...

Hy-Tek Hurricane 103 The Hy-Tek Hurricane 103 is a family of single-engined, high wing tricycle gear-equipped aircraft that were available in kit form from Hy-Tek Hurricane of Aurora, Oregon.Cliche, Andre: ''Ultralight Aircraft Shopper's Guide'' 8th Edition, pages ...

ISON Airbike The ISON Airbike and Tandem Airbike are a family of American high-wing, tractor configuration ultralight aircraft, that were available in kit form. The single-seat Airbike was introduced in 1994 and the two-seat Tandem Airbike was unveiled in ...

Preceptor N3 Pup The Preceptor N3 Pup is a family of ultralight, tube-and-fabric, high-wing, homebuilt aircraft. Kits were produced and marketed by Preceptor Aircraft, of Rutherfordton, North Carolina.Vandermeullen, Richard: ''2012 Kit Aircraft Buyer's Guide ...

Spacek SD-1 Minisport The Spacek SD-1 Minisport is a Czech amateur-built aircraft, designed by Igor Špaček and produced by Spacek sro of Hodonin. The aircraft was also produced for a short time in the United States by SkyCraft Airplanes of Orem, Utah as a lig ...

;2703 *

Airmotive EOS 001 The Airmotive EOS 001 is an American homebuilt aircraft that was designed and produced by Airmotive Engineers of Pontiac, Michigan. The aircraft was supplied as a kit for amateur construction, but is no longer available.Plane and Pilot: ''1978 ...

American Sportscopter Ultrasport 254 The American Sportscopter Ultrasport 254 is an American helicopter that was designed and produced by American Sportscopter and first flown in July 1993. The aircraft was produced by Light's American Sportscopter Inc from 1999. The aircraft wa ...

CGS Hawk The CGS Hawk is a family of high wing, strut-braced, pusher configuration, single and two-seats-in-tandem ultralight aircraft, designed by Chuck Slusarczyk and manufactured by CGS Aviation.Purdy, Don: ''AeroCrafter – Homebuilt Aircraft So ...

Exkluziv Joker The Exkluziv Joker is a Slovakian ultralight trike that was designed by Jindrich Zahumensky and produced by Exkluziv sro of Topoľčany. The aircraft is supplied as a complete ready-to-fly-aircraft.Bayerl, Robby; Martin Berkemeier; et al: ''Wo ...

* Falconar Golden Hawk *

Kolb Firestar The Kolb Firestar is a family of American open cockpit, high wing, pusher configuration, conventional landing gear-equipped ultralight aircraft that was produced in kit form by Kolb Aircraft of Phoenixville, Pennsylvania and intended for amat ...

* RemSchetMash Robust *

US Light Aircraft Hornet The US Light Aircraft Hornet is an American two-seats-in-tandem, pusher configuration, tricycle gear, strut-braced high wing ultralight aircraft, that was produced US Light Aircraft Corporation of Ramona, California between 1994 and circa ...

Specifications (2702)

References

External links

Official 2702 page
on

Archive.org The Internet Archive is an American digital library with the stated mission of "universal access to all knowledge". It provides free public access to collections of digitized materials, including websites, software applications/games, music, ...