Model A Aircraft Kit

s.e.charles said:
i read the oil pan was finned to allow cooling
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You may be thinking of fins inside the oil pan to provide more oil to the rods. I saw this in a youtube video titled "Howard Henderson's Model A Ford powered Pietenpol Air Camper". Start at the 4:20 mark. It gives a lot of the engine modifications.
 
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drezin said:
I built a pietenpol 40 yrs. ago. Sold it recently, To old to get in and out of it. Good flying airplane. Had the model A engine. Had the standard oil pan but I put a high compretion head on it.
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Good info to know. May I inquire how much you got for her? Since it's a special plane in the eyes of the FAA, what level license did it require? (sport?)
 
Mister Moose said:
I dunno. For what it would cost to get a rebuilt and airworthy Model A engine, buy the kit and build it, why not just spend 20k on a nice used Cessna 150? Better resale, 2 seats, 100kts on a reliable continental engine. Not to mention an enclosed cabin and a windshield you can see through.
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Good point. Add about $15,000 for a license.
 
katy said:
Are you saying that one doesn't need a license to fly a Pietenpol?
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:rolleyes: WELL Basically Yes but not as strict. A Sport Pilot certificate will suffice, and they are easy to get. As to why, if you go by the EAA's premise, Pietenpol was a kit plane where it was constructed by the owner. When I looked into building one for myself a few years ago, they were still recognized as an Experimental aircraft, and so the pilot only had to follow the guidelines for licensing as an experimental craft.
 
A sport license limits you to small, slow, fixed gear, fixed prop aircraft below 1,320 lbs (600 kg) gross takeoff weight. So that means for 2 180 lb guys and 20 gallons fuel, (120 lbs) you have 840 lbs for the airframe and engine.

The Pietenpol is a taildragger, and that will require very good stick and rudder skills, not a casual few hours of training. Add the obstructed forward view and you have a challenging aircraft that (might) qualifies for a basic level of licensing. The Pietenpol site gives no information on stall speed or maximum gross weight, so it's not clear if it qualifies for a sport license.

There is a difference between licensing the aircraft and licensing the pilot.
 
Well I don't have an answer to my original question, but this has been very interesting. I'm kind of glad I asked about it now.
 
The first Pietenpol had model T engines.
There is one in a museum somewhere.
There is one in an airplane museum in the Morgan Hill, Ca. Area with a model B engine.
I have seen it several times.
 
Automotive and airplane engines are similar, however, airplane engines have a much stronger front main bearing to support the propeller.

When using an automobile engine in an airplane, the rear main in the automobile engine becomes the front main when used in an airplane.

In the automobile application, the rearmost main thrust bearing is only loaded when the clutch pedal is depressed. In an airplane application, the opposite thrust bearing is continuously loaded as the propeller pulls the airplane through the air.

Another problem is the bending loads imposed on the crankshaft flange by the propeller which may result in a fatigue failure. In an automobile application, the bending loads are very small. In an airplane application, the bending loads can be large if one side of the propeller grabs more air than the other side, or if the propeller is not balanced.
 
Aarongriffey said:
The first Pietenpol had model T engines.
There is one in a museum somewhere.
There is one in an airplane museum in the Morgan Hill, Ca. Area with a model B engine.
I have seen it several times.
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I thought the Sky Scout came after the Air camper.
Sky Scout used the T engine.
 
Terry Burtz said:
Automotive and airplane engines are similar, however, airplane engines have a much stronger front main bearing to support the propeller.
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Interesting.

A few other differences:

Aircraft engines are rated and constructed to operate at 75% power for ~90% of their operating life, car engines are not.

When an aircraft engine fails or exhibits signs it's about to fail you can't pull off to the side of the road and call AAA.

Aircraft engine castings are (except the rare automotive conversions) made out of aluminum for the obvious weight savings.

Aircraft engines are typically made to run on the higher octane aviation fuel and unless you qualify for the related STC you cannot run any variety of auto gas. Vapor pressures are different as well, and can cause fuel starvation if mis-managed. (Some aircraft have vapor collection and return tanks)

Aviation octane does not equal automotive octane, although if you break it down to the research method and the motor method you can do the conversion.

Aircraft carburetors have a mixture control to adjust for altitude and power settings, automotive ones don't.

Aircraft carburetors are subject to icing, and are equipped with carb heat. Carb icing can be fatal, nothing to ignore here.

Aircraft engines almost always (And I never thought there would be an exception) have 2 magnetos and 2 sets of spark plugs that are independent. Once upon a time a manufacturer made an engine with a dual magneto off the same drive gear. That ended up being an unpopular design, whadayaknow, they were not truly independent. I myself have endured an engine failure from a slipping magneto drive gear. So a seasoned pilot will more than likely look askew at an engine with only 1 magneto. The recent tragic loss of the B-17 909 was due in a large part to multiple magneto problems.

Aircraft engines have annual inspections, logbooks that record all maintenance, minimum compression to be legal, and all work must be signed off by a licensed FAA powerplant mechanic. (Yes, the owner can do minor stuff like oil changes)

All engine parts must carry the proper FAA/PMA sourcing and approval.

Probably more than you wanted to know, but it illustrates how far from a 'typical' aircraft engine the Model A is. Just the oil pump alone and gravity feed in turbulence or unusual attitudes gives pause.

However as a historical relic, it's great to have some operating examples around.
 
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Well that was a comprehensive rundown on aeroplane piston engines and fuel Mister Moose. There is only one thing I would add that is of interest, and only one.
The cylinders are steel and the cylinder heads aluminium. They are screwed together, held in correct position and then the base attachment holes drilled. In the older radials, that join can leak a little before it takes up. If they don’t take up they are changed. Cylinders are nitrate coated to harden. For a period they were hard chromed. I used these and they seemed good but the process was discontinued.
The dual magnetos driven off one drive didn’t install confidence in me either although I never flew one.
That was a good and thorough report Mister Moose.
 
As far as the single drive for the magnetos, I've flown them [ only in good visual weather]. But, It was an incredibly stupid idea.

I've also flown single magneto J2. Very underpowered. 37 HP if I remember correctly.
 
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