Model A aluminum head?

Bernard Pietenpol built his two-seat "Air Camper" monoplane in 1929 with the Model A engine and it was quite successful (albeit a bit underpowered with two adults onboard). He later redesigned the ship as a single-seat version (called the "Sky Scout") for the purpose of showing that a Model T-powered airplane was possible.

The Air Camper/Sky Scout was a very successful design and is often credited with starting the amateur/homebuilt movement in the US. Over a hundred are still flying today worldwide and many new ones are currently under construction. While most builders nowadays opt for more powerful engines (the 85hp Continentals and 100hp Chevy Corvair engines being the most popular), about 15% still use the Model A engine because of its vintage appearance.

mndodge said:
I saw a "T engined" one when looking on line......did they come with or recommend a parachute, they would definitely not be my first choice of flying the friendly skies, that would be my definition of a true dare devil ...sheesh!!!
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MNDodge, why would you think that? The T-powered Piet flew well (although slow) and several have been built over the past 80 years. While it has not been as popular as the Air Camper (because, when it comes down to it, a two-seater isn't much harder to build than a single-seater) a few T-powered Scouts still fly. Admittedly, of those single-seat Scouts built over the years, most have since been upgraded to the more-powerful Model A engine.

mndodge said:
If the head does not have two sparkplugs per cylinder, it is not an airplane head. Mike :)
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Mike, that's not entirely true. While it IS true that modern made-for-aviation engines have two independent ignition systems (to include dual plugs), there is no requirement for a homebuilt aircraft to do so. Therefore, it is not unusual to find single-plug engines legally installed in some airplanes. (But, admittedly, they're not very common either.)

It's a common misconception that aircraft engines are equipped with dual ignition systems for redundancy. According to the FAA, the official purpose of dual plugs is for a better flame pattern in the cylinder. Nonetheless, I'm with the masses in believing that two sources of ignition are safer than one!

Harvey
 
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PS

Aftermarket aluminum heads are still being made for the Model A engine. Snyder's is one source. Dual plug heads are also available.

Note that almost all Model A engines installed in Pietenpol airplanes are liquid cooled. Several attempts have been made over the years to convert the engine to air cooled (in the interest of simplifying/lightening the installation) but the inability to get airflow between the cylinders results in the aft ones running very hot. Also, the slow speed of the Piet (it's a 60mph flyer with the A engine) provides marginal slipstream air for cooling.

For those readers who are rolling their eyes at the thought of someone flying behind a converted 80 year old car motor these days, note that the use of the Model A engine in aircraft was popular in the pre-war years when light, purpose-built aviation engines were too expensive for most small airplane builders. Additionally, the early light aircraft engines were not all that more reliable than the car motors of the time. Nowadays, much better aviation engines are readily available to the homebuilders but some still prefer to use Model A engines due to their historic/vintage appeal. And it shouldn't surprise most of you that the converted engine's reliability is directly attributable to the care of its assembly and installation, and its continuing maintenance afterwards.

Aircraft-engined Piets are cute but hardly attract as much attention at the gas pump as a Model A-powered Piet. (And isn't THAT why we love to fiddle with old cars and airplanes??? :D )

Harvey
 
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HarveyH said:
PS

Several attempts have been made over the years to convert the engine to air cooled (in the interest of simplifying/lightening the installation) but the inability to get airflow between the cylinders results in the rear ones running very hot. :D )
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The rear ones on the plane are the front ones in an A.
 
Mike V. Florida said:
The rear ones on the plane are the front ones in an A.
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This is true since the motor flies backwards when compared to the original car installation. (For aviation use, the propeller is attached to the motor's output end.) I've changed my post to read "aft" cylinders to denote the rearwardmost cylinders in relation to the incoming cooling air.

Harvey
 
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HarveyH said:
This is true since the motor flies backwards when compared to the original car installation. (For aviation use, the propeller is attached to the motor's output end.) I've changed my post to read "aft" cylinders to denote the rearwardmost cylinders in relation to the incoming cooling air.

Harvey
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Harvey, who wound up with Lou Riekert's "Peit" down there? Was it you?
 
No, I didn't get it. (I was too late.) Nobody really knows who has it now, it's been traded a couple of times since Lou let it go. That's a shame because I understand that Lou did some good initial work on it.

Harvey
 
I am taking flight lessons on a Cessna 172 and the engine controls are very similar to a model A. You adjust the carb with a GAV in the cockpit.
Wish someone would cast those finned heads....absolutely gorgeous and efficient.
 
The Pietenpol is a home built plane from plans. There were probably hundreds made through the years and the plans are still available on the internet. You can still power them with Model A engines and there are instructions on how to modify the engine for air use too. It is generally a mild hop up with counter balanced crank and pressure oil system.

The preferred engines are now VW, Corvair or Subaru water cooled boxer engine.

They are a mono wing with a wide cord so takeoff and landing is about 35 MPH. There is lots on the internet and a fascinating story with a lot of information.

Richard
Anaheim CA
 
The head does have 2 plugs per cyl. Also the angled fins are because of the spiral slipstream from the turning prop which directs the air parallel to the fins. Also you can see the magnetos in the pictures
 
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