Sauer Flugmotorenbau (Sauer Aircraft Engines) or "Sauer" is a German manufacturer of

aircraft engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years ma ...

s based at Ober-Olm in

Germany Germany, officially the Federal Republic of Germany (FRG),, is a country in Central Europe. It is the most populous member state of the European Union. Germany lies between the Baltic and North Sea to the north and the Alps to the sou ...

History

The first certified 4 stroke engine entered the market in 1987. The 4 stroke engines are certified according to CS-22 Subpart HCS-22
CS-22 for use in

motorglider A motor glider is a fixed-wing aircraft that can be flown with or without engine power. The FAI Gliding Commission Sporting Code definition is: a fixed-wing aerodyne equipped with a means of propulsion (MoP), capable of sustained soaring fligh ...

s, CS-LSACS-LSA
CS-LSA and CS-VLACS-VLA
CS-VLA type of aircraft. They also makes engines for use in ultralights and

Homebuilt aircraft Homebuilt aircraft, also known as amateur-built aircraft or kit planes, are constructed by persons for whom this is not a professional activity. These aircraft may be constructed from "scratch", from plans, or from assembly kits.Armstrong, Kenn ...

. The production consist of 4 stroke engines based on VW "Type 1" engines (commonly known as air-cooled beetle engines) and based on the later

Wasserboxer The Volkswagen wasserboxer is a four cylinder horizontally opposed pushrod overhead-valve (OHV) petrol engine developed by Volkswagen. The engine is water-cooled, and takes its name from the german: "wasserboxer" ("Water-boxer"); with "boxer" b ...

. Sauer also makes 2-stroke engines.Sauer Flugmotorenbau
Sauer Flugmotorenbau There have been development of a turbocharged 2 cylinder 4 stroke engine based on the Weber MPE
, Weber MPE "recreational engine" in 2009-2010, but no commercial available engine exists to date.
Development

Products

There are two main versions of the boxer 4-stroke engines. Those with the casing of air-cooled beetle engines, and those with the largely similar, but stronger

casing used in late VW vans before the

Volkswagen Transporter (T4) The Volkswagen Transporter (T4), marketed in North America as the Volkswagen EuroVan, is a van produced by the German manufacturer Volkswagen Commercial Vehicles between 1990 and 2004, succeeding the Volkswagen Type 2 (T3) and superseded by th ...

. Even though the

engine is water-cooled, this involves only the cylinders and the top. The casing has no water lines, it is only stronger built. This makes it possible to convert the

"back" to an air-cooled engine. The benefits of this conversion is the added strength, and the size of the

casing will accept larger cylinders. In general it becomes a much more robust engine compared with engines using the original air-cooled casing.Water to air
Water to air. These "water to air" converted engines are sometimes referred to as the misnomer ''oxyboxer'' in automobile VW engine circles.

4 Stroke engines for experimental and ultralight

Sauer S 1800 UL The Sauer S 1800 UL is a four stroke aircraft engine designed for homebuilt and ultralight aircraft.
Sa ...

- 68 HP, in production *

Sauer S 1900 UL The Sauer S 1900 UL is a 4 stroke aircraft engine for homebuilt and ultralight aircraft.
Sauer Flugmotoren ...

- 75 HP, in production * Sauer S 2100, Sauer S 2100 UL - 80 HP, replaced by the S 2200 UL. Sometimes referred to as Sauer 2100/2200 UL. The specs are identical to the S 2100 certified engine. *

Sauer S 2200 UL The Sauer (German and Luxembourgish, , ) or Sûre (French, ) is a river in Belgium, Luxembourg and Germany. A left tributary of the Moselle, its total length is . Rising near Vaux-sur-Sûre in the Ardennes in southeastern Belgium, the Sauer ...

- 85 HP, in production *

Sauer S 2400 UL The Sauer S 2400 UL is a 4 stroke aircraft engine for Homebuilt aircraft, homebuilt and ultralight aircraft.

- 100 HP, in production *

Sauer S 2100 ULT The Sauer S 2100 ULT is a turbocharged four-stroke aircraft engine for homebuilt and ultralight aircraft.
S ...

- 115 HP Turbo,

casing, probably still in production *

Sauer S 2500 UL The Sauer S 2500 UL and Sauer S 2500 ULT are four-stroke aircraft engines for homebuilt aircraft
Sauer Flug ...

- 100 HP,

casing, obsolete * Sauer S 2500 UL, Sauer S 2500 ULT - 126 HP,

casing, obsolete *

Sauer S 2700 UL The Sauer S 2700 UL were a 4 stroke aircraft engine for homebuilt aircraft Homebuilt aircraft, also known as amateur-built aircraft or kit planes, are constructed by persons for whom this is not a professional activity. These aircraft may b ...

- 105 HP,

casing, obsolete (appears as a "UL" in old price lists. Uncertain if a certified version also existed)

4 Stroke certified engines

Sauer S 1800 The Sauer S 1800 is a family of German four-stroke aircraft engines, certified according to JAR 22-H (CS-22 subpart H)

- 60 HP, 3 variants, in production *

Sauer S 2100 The Sauer S 2100 is a family of four-stroke aircraft engines, certified according to JAR 22-H (CS-22 subpart H) ...

- 80 HP, 2 variants, in production *

Sauer S 2500 The Sauer S 2500 is a family of four stroke aircraft engines certified according to JAR 22-H (CS-22 subpart H)EASACS-22/ref> Design and development The engine is based on the Wasserboxer, extensively modified for aircraft use and all the parts ...

- 94-100 HP,

casing, 4 variants, in production * Sauer S 2500 T - 126 HP,

casing, obsolete

2 Stroke Engines

Various engines from 14.9 to 100 HP, single cylinder to 3 cylinder. These engines are re-branded

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 engi ...

engines built by Sauer. The specifications are identical to the corresponding Hirth engine. *

Sauer S 210 The Sauer (German and Luxembourgish, , ) or Sûre (French, ) is a river in Belgium, Luxembourg and Germany. A left tributary of the Moselle, its total length is . Rising near Vaux-sur-Sûre in the Ardennes in southeastern Belgium, the Sauer flo ...

- 210cc, 14.9 HP, ( Hirth F-36) * Sauer S 330 - 313cc, 28 HP, (

Hirth F-33 The Hirth F-33 is a single cylinder, two stroke, carburetted aircraft engine designed for use on ultralight aircraft, including powered paragliders and ultralight trikes. the engine is noted for its extremely light base weight of . It is ma ...

) * Sauer S 550 - 521cc, 50 HP, (

Hirth F-23 The Hirth F-23 is a twin cylinder, horizontally-opposed, two stroke, carburetted or optionally fuel injected aircraft engine designed for use on ultralight aircraft. It is manufactured by Hirth of Germany.Cliche, Andre: ''Ultralight Aircra ...

) * Sauer S 625 - 625cc, 65 HP, ( Hirth 3203) * Sauer S 650 - 625cc, 70 HP, (

Hirth 3503 The Hirth 3502 and 3503 are a family of liquid-cooled, in-line twin-cylinder, two-stroke, carbureted aircraft engines, with optional fuel injection, designed for use on ultralight aircraft and small homebuilts. It is manufactured by Hirth of ...

) * Sauer S 950 R - 939cc, 86 HP, ( Hirth 3702) * Sauer S 950 R 100 - 935cc, 100 HP, (

Hirth 3701 The Hirth 3701 is an in-line three-cylinder, two-stroke, carburetted aircraft engine, with optional fuel injection, designed for use on ultralight aircraft and small homebuilts. It is manufactured by Hirth of Germany. Development The 3701 ...

)

Applications

Groppo Trial The Groppo XL and Groppo Trail are very similar single engine, tandem seat, high wing ultralight aircraft designed and built in Italy. Both can be supplied complete or in kit form. The two models differ chiefly in undercarriage type. Design and ...

Groppo Trial
, Groppo Trial. * AMS CaratAMS Carat
AMS Carat. *

Alpi Pioneer 200 The Alpi Pioneer 200 is an Italian ultralight and light-sport aircraft, designed and produced by Alpi Aviation, of Pordenone. The aircraft is supplied as a kit for amateur construction or as a complete ready-to-fly-aircraft.Bayerl, Robby; Mar ...

Alpi Pioneer 200
Alpi Pioneer 200 *

Scheibe SF 36 The Scheibe SF 36 is a German two-seat self-launched powered sailplane designed and built by Scheibe Aircraft. Design The SF 36 is an all composite sailplane with an engine mounted at the front. It is a low-wing monoplane with airbrakes fitt ...

* Scheibe SF 25 * Skyranger SWSkyranger SW
Skyranger SW *As a drop in replacement in older

Motorglider A motor glider is a fixed-wing aircraft that can be flown with or without engine power. The FAI Gliding Commission Sporting Code definition is: a fixed-wing aerodyne equipped with a means of propulsion (MoP), capable of sustained soaring fligh ...

s originally fitted with Limbach engines.

Naming

4 stroke certified engines

The naming format changed in 2003. The current naming format is: S aaaa-(b)-(XYZ)c *S refers to Sauer Flugmotorenbau GmbH *aaaa refers to engine displacement in (approximate) cubic centimeters (cc) *b=1 for single ignition, b=2 for double ignition *X is a letter describing a particular equipment *Y is a letter describing the propeller flange *Z is a letter for a special utilization *c=1 for hydraulic valve lifters Whereas the old naming format found in older engines is:Old Naming Convention
Old Naming *S X aaaa Y b Z *S refers to Sauer Flugmotorenbau GmbH *X is a letter describing a particular equipment (A or S) *aaaa refers to engine displacement in (approximate) cubic centimeters (cc) *Y is a letter describing hydraulic valve lifters (Y = H) *b=1 for single ignition, b=2 for double ignition *Z is a letter describing the propeller flange

4 stroke engines for experimental and ultralight aviation

There is no defined naming for these engines from the manufacturer, but they all are named according to: *S aaaa UL(T) *S refers to Sauer Flugmotorenbau GmbH *aaaa refers to engine displacement in (approximate) cubic centimeters (cc) *UL refers to Ultralight *T refers to Turbo

References

External links

* {{Sauer aeroengines Aircraft engine manufacturers of Germany