Rethinking the Rotax 912

By Ed Downs

Long used in U. S. experimental aircraft and many certified European aircraft, the Rotax 912 has become the almost-standard engine of choice for S-LSA aircraft designers.  But, ask most American pilots about flying behind a Rotax, and you get the “What, me fly with a snowmobile engine?” question followed by a wide-eye look of horror when told that the 912 delivers its maximum rated 100 horsepower at 5800 rpm. Most simply equate the name Rotax with the famed two stroke engines of the Ski-Doo snowmobile and Sea-Doo watercraft.  Many conclude that the Rotax 912 is simply a variation of its well-known two-stroke counterparts.  Nothing could be further from reality.