Specification:
- Displacement: 0.569 cu in (9.32 cc)
- Bore: 0.945 in (24.0 mm)
- Stroke: 0.811 in (20.6 mm)
- Practical R.P.M.: 2,400-13,000
- Output: 1.0 hp @ 10,000 rpm
- Weight w/muffler: 16.26 oz (461 g)
- Includes: 40NA carburetor, muffler
- Recommended Props: Sport & aerobatic; 13x6, 12x6-8; Scale: 13x6-7, 12x6-8

A big performance boost for 40-size planes!

Ushering in a new era in O.S. 4-stroke technology: the 56FS-a. It's the first in the alpha series, with the latest advancements for boosting your plane's performance.

• Mounts with no-mod ease in the same space as the 52FS.
• In addition to less noise, the muffler features a multi-positional manifold with a rubber O-ring that helps prevent oil leakage.
• A newly 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.

It's like giving your 40-size plane a new lease on life!