August 2013 Backward Glances Mounted Paddle - Photo 53323320

Back to Article

With no reverse gear, this paddle was for more than emergencies. You can disengage the prop, engage reverse gear, and use the tires as paddles—but it’s not efficient.

The Ford GPA was originally designed as a recon vehicle but saw use with combat engineer bridge-building units. Unlike its German counterpart, it was designed to be capable in surf, but wasn’t the safest rig in even moderately heavy weather. Missing on Saft’s GPA is the surf shield, a foldable clamshell to minimize the water rolling over the bow.

Richard Saft’s 1943 type 166 is set up as it would have been used as a recon vehicle, complete with MG34 and plenty of drum magazines for shooting and scooting.

The Schwimm prop is driven from the engine crankshaft via a short shaft that extends thru the hull. The prop and gearbox is on a hinged bracket, lowered manually and engages with a dog clutch. Thrust from the prop keeps the dogs engaged.

With no reverse gear, this paddle was for more than emergencies. You can disengage the prop, engage reverse gear, and use the tires as paddles—but it’s not efficient.

Vee-dub in a tub! This 1131cc, 25hp air-cooled flat-four is very similar to postwar VW engines. The engine sits in a sealed compartment and cooling air comes in from between the rear seats and blows the hot air out through vents forward of the deck lid. The muffler sits above the deck lid.

As with any military vehicle in any army, this interior is for the young, the limber, and the tough. The driving position is not bad, even for fairly tall folks, but you need acrobatic skills to get in. The racks on either side of the cockpit hold 50-round ammo drums for the MG34. The lever behind the main gearshift engages the four-wheel drive. Back is rear drive, the middle position is four-wheel and forward engages the creeper gear (5.86:1, normal first is 3.60:1) when the main shifter is in Neutral

The departure angle of the Seep was actually a little better than the jeep. Besides the jerrycan and bucket, a Danforth anchor was normally carried, and the operator’s manual showed you how to use it for recovery on land as well as anchoring in water.

There’s plenty of room to move around in here. The controls are more or less the same as the land jeep but PTO controls are added for the propeller and bilge pump. The steering wheel controls the front tires and the rudder simultaneously. These canvas seats are incorrect for a GPA. Originally, they would have been leather stuffed with kapok so they could be used as floats. The kapok cushions made the GPA seats among the most plush in the U.S. Army.

The GPA engine is the same as the Ford-built GPW land jeep (and the Willys-built jeep) but with some external additions. The pulley on top is what drives the capstan winch on the bow and is engaged via a lever on the dash. The GPA and GPW engines were functionally interchangeable but marked differently. Finding a GPA-marked engine is difficult, as many have been changed out to Willys or GPW engines.

The GPA’s water propulsion and steering is more like a boat. The propeller and rudder operate in a tunnel, which protects them from debris. The GPA prop is notorious for its inefficiency and some GPA owners have had new props built which greatly improve thrust. As you can see, the axles and suspension hang in the water, so increased axle maintenance is a must.

A Seep versus Schwimm water drag race was held. Here they are at full speed with the GPA ahead by a length and rapidly gaining distance.

The Seep has a fair bit of freeboard with a light load. The open lid on the forward deck allows air to go to the radiator, and the air exits thru side vents just under the canvas splash curtains. In surf or rough water, the deck intake and side vents can be closed. Air is then drawn in from under the dash and exits thru a vent that opens just above the dash, but airflow is limited and overheating can result. Spinning the wheels at the same time as the prop adds a little speed, but puts a heavier load on the engine. Spinning the wheels alone can deliver a speed of about 1.5 mph.

To enter the water, the straps holding the propeller bracket to the deck lid are released and the lowering rod fitted. You drive into the water at a low speed in First gear, or creeper gear as ground conditions demand, and when afloat, the prop is lowered by the rod. The engine should be at idle so the dogs will engage properly. Once in the water, the trans is put into Neutral and speed is controlled with the gas pedal.

The GPA is driven into the water at a slow pace in low range First gear with the prop PTO engaged and spinning. Once in the water, the wheels are disengaged by placing the transfer case in Neutral. The highest speed, 5.5 mph, can be obtained by using Second gear and full throttle but it only delivers about 1.25 mpg. Third gear full throttle delivers an extra mile per gallon but 1 mph less speed. The most economical combination is Third gear and quarter throttle, which delivers 5.5 mpg and 2.5 mph. High engine speed and load can result in overheating.

A tranquil day on the water in the Schwimm, and that’s the environment in which it was designed to operate. Remember, it’s a car that floats, not a boat that drives! The prop is designed to deliver maximum thrust at 2,300 engine rpm. Because they can suddenly spring a serious leak and no factory pump is fitted, most Schwimm owners install a bilge pump for safety.