This design was originally started by Rima Industrial SA in 2006 when they acquired the die casting foundry of the VW engines in Brazil. In 2009 the first prototypes were build and experience was gained and flight hours accumulated. In 2012 Rima's project was taken over by MOTORAV Industria e Comercio LTDA, located in the town of Bocaiuva, Minas Gerais - Brazil in the Amazonas.
A large number of aircraft builders, designers, analysts worked together to design this engine specifically for the experimental aircraft market. The work resulted in significant improvements to the engine crankcase, one piece crankshaft, new cylinder heads, camshaft, oil coolers and pump.
Although the engine has its history found in the venerable VW motor by Joseph Ganz, it is modernized and brought into the 21st century by MOTORAV.
Finite Element Analysis (FEA) simulation was conducted by ITA (Aeronautical Technological Institute) to compare the VW regular engine case with the Motorav design. It became clear that the original VW design showed stress areas which were not desired in an aircraft application and could lead to failures in flight. From this analysis MOTORAV implemented reinforcements in the critical areas.
The company developed four totally new cylinder heads for the engine. This design considered a full performance analysis to develop and optimize the intake plenum size and volume, intake and exhaust manifolds, cylinder head ports, intake and exhaust valve diameters, camshaft profile, valve spring stiffness and pushrod material.
A computational fluid dynamics study confirmed the mixture flow inside cylinder head regarding the intake and exhaust ports, this resulted in optimized power delivery at the lowest fuel consumption.
To make sure that the crankshaft does not flex under stress it is made from one casted piece. This gives rigidity and reduces torsional loads. Stress and fatigue analysis were carried out to assess piston forces combined with propeller gyroscopic loads.
The table below shows a short list of the specification of this engine.
|MOTORAV Engine 100 HP Specifications|
|Maximum Power/RPM||100 hp @ 2900 RPM|
|Bore x Stroke||3.878 in x 3.701 in|
|Oil Quantity / Type||4 Quarts SAE 15W50 or equivalent|
|Weight||189 lbs including alternator|
|Aviation Fuel||Octane 100 / 100 LL|
|Fuel consumption @ 75%||6 to 8 GPH|
More detailed information can be found in the engine specifications PDF.
Below a detailed photo impression of the engine seen from different angles.
More detailed information and history about the VW air cooled engine can be found at its Wikipedia page.
Motorav Industria can be contacted at the addresses below:
|Estrada da Fazenda Jacaré, nr 1200|
|Distrito Industrial, Bocaiuva-MG, Brazil|
|+55 31 3329 4197 or +1 205 981 2200|
Text and images used with permission (pending) of Motorav.
A video impression of the engine and the company can be seen in their YouTube channel: Presentation 2018.Written by EAI.