Stratus 2000, Inc was an American aircraft engine manufacturer based in Camano Island, Washington and later in Corvallis, Oregon.

[3][4][5][6] The company built two Subaru-derived designs, the Stratus EA 81 based on the Subaru EA 81 automotive engine and the Stratus EJ 22 based upon the Subaru EJ 22 automotive engine.

The company also designed its own 2.2:1 ratio propeller speed reduction unit to slow the crankshaft speeds down to those that can be used by aircraft propellers efficiently.

[1][3] Some existing airframe designs, like the Zenith CH 601, have been adapted for the Stratus engines, while other aircraft have been designed around the engines from the start, such as the Airdale Backcountry.

Stratus powerplants have also been used as retrofits in production aircraft, such as the Cessna 150.