American Turbine Application and Engineering Data

309 SERIES JET UNITS ARE DESIGNED PRIMARILY FOR LIGHT WEIGHT PLANING CRAFT WITH GASOLINE ENGINES

Matched to the correct engine the appropriate 309 series AmericanTurbine jet unit can be more economical than most alternative marine propulsion systems. Operating in the correct engine R.P.M. range results in significant fuel savings. To help achieve this, only American Turbine offers up to 9.5" impellers with a variety of nozzle discharge diameters to precisely match the jet unit to the engine.

309 jet units can be used with some high speed diesels and in displacement speed craft but careful planning is needed. In such cases, consult the manufacturer or your American Turbine dealer.

HULL SHAPE

In a planing craft some vee angle in the bottom is desirable, remaining constant over the aft section. (Chine and keel lines parallel in this region). The bow should be easy rising. Underwater appendages such as keel, planing strakes, etc.. can interrupt the water flow into the jet unit. Avoid any such interferences 6 feet in front of the intake. Strakes wider out than the intake are acceptable and desirable.

There should be no hook and only a slight amount of rocker in the hull bottom. A contour keel with a 12" radius is the most desirable. A concave bottom will cause the pump to cavitate and not perform well. Deadrise angle should be from 5 to 20 degrees.  

BOAT LENGTH
	Single	12-24 feet
	Twin	22-30 feet
BOAT WEIGHT
	Single	5,200 lbs. AUW (gross boat weight)
	Twin	10,000 lbs. AUW
ENGINE SIZE
	LITERS	AUW (gross boat weight)
	3.0	2100 lbs.
	4.3	2700 lbs.
	5.0	3200 lbs.
	5.7	4000 lbs.
	5.8	4000 lbs.
	7.4	5200 lbs.
	7.5	5200 lbs.
	8.2	5200 lbs.
TRANSOM ANGLE
	Pump Model	Degree
	AT-309	9-15
	SD-309	8
	FW-309	12-16
SPACE REQUIREMENTS
	SEE DRAWINGS

 

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