O.S. FS56-a 4-Stroke w/Muffler

A big performance boost for 40-size planes!

A new era in O.S. 4-stroke technology, the FS56-a is the first in the “a” Series — with the latest advancements for boosting your plane's performance. It's like giving your 40-size plane a new lease on life. Bolt in the O.S. FS56-a 4-stroke powerhouse, and you and your fellow fliers will all be saying: This engine rates an “a”!
Displacement: 0.569 cu in (9.32 cc) Bore: 0.945 in (24.0 mm) Stroke: 0.811 in (20.6 mm) Weight w/muffler: 16.26 oz (461 g) Practical rpm range: 2400-13,000 Output: 1.0 ps @ 10,000 rpm Includes: 40NA carburetor, muffler

O.S. Two Year Limited Warranty
  • Mounts with no-mod ease in the same space as the FS-52.
  • In addition to less noise, the muffler features a multi-positional manifold with a rubber O-ring that helps prevent oil leakage.
  • A designed lubrication system eliminates the need for crankcase ventilation.
  • The 40NA carburetor is equipped with a venturi that reduces the chance of fuel leaking out onto the cowl, while also creating more positive air/fuel flow.
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