John Dilatush's Pietenpol

John Dilatush's Subaru-Powered Pietenpol

revised June 25, 2003

This is a beautiful Rocky Mountain valley north of Salida, Colorado. "Salida" means "exit" in Spanish, and in this case Salida is the western exit from the Arkansas River canyon and the Royal Gorge. Down in this little valley is the town of Buena Vista and the Central Colorado Regional Airport, field elevation 7,946' MSL. The day this photo was taken the temperature was about 80F which with an altimeter setting of 29.92" and a dewpoint of about 45F yields a density altitude of about 11,100 ft. Now how well is a Ford 'A' powered Pietenpol going to do in that kind of environment? Here's one man's solution to that problem...

This is a beautiful, straight-axle, stock, 1929-plans-built Pietenpol Air Camper by John Dilatush of Salida, Colorado. Stock except for the engine... and that's what this story is all about. But before we go any further, just forget about how the airplane's nose and cowling look. There is a reason for that bluff, squared-off nose!

Here's the starboard side of the airplane... just as clean as the port side. Just a hint of dihedral in the wing. Vertical cabanes (which means John did the weight and balance and engine mount calculations very carefully), low turtledeck. Hmmm... let's zoom in on that front cockpit...

A passenger's side door! One of the peculiarities of the front cockpit of a Pietenpol is the contortions required for a passenger to get into and out of the front 'pit, and it's usually done from the port side. On John's Piet, with no X-bracing of the cabane struts and with the drop-down door here, it's far less of a gymnastic routine to get in and out. Nice artwork, too... it shows "Mountain Piet" huffing and puffing to get over the Rockies. Also visible in this shot are the two links that tie the main gear axle to a fixed tube to keep the axle from rotating when the brakes are applied but still allow vertical motion of the axle as the bungees flex and the plane rides over bumps on the ground.

Here's the logo on the fuselage sides.

Here's the front cockpit, characteristically simple. The airplane has an aux tank in the wing but this is the main tank. Very simple and clean upholstery, immaculate finish on the woodwork, absolutely no gauges on the front panel, a nice aluminum cover on the throttle linkages, toe brakes on the rudder bar for the pilot's rudder controls, and... not much else. This is basic stick-and-rudder flying at its best. Now let's look at the main office.

Not much out of the ordinary here, is there? But wait! What is that funny lever below the throttle? Here's a hint: the placarded up/down arrow says "manifold pressure". This is a manual wastegate control for the turbocharger on the Subaru EA-82 and this is what gives "Mountain Piet" its muscle. And what's that funny black box under the right side of the panel? No, it's not a transponder; it's the engine control module, aka "computer". The pin-outs, connections, and modifications needed for this aero conversion are all well documented in back issues of Contact! in articles by Don Parham and others. John has proven that if we can put men on the moon, we can sure figure out how to make a 4-cylinder auto engine work in an airplane! Oh, one more thing to note: see the altimeter reading? Sitting on the ground? Told you it was high country!

The front cockpit, from a different angle. The cutouts for the pilot's feet are pretty much stock... somewhat smaller than most builders choose to make them to make it easier to climb in and out. Bracket for handheld radio down to the right side. And an extra lever and knob on the right side of the cockpit. We'll talk about that extra lever (the one with the wooden handle) in a moment, but the black knob is the tension control for elevator trim on that bellcrank.

One more shot of the office before we leave. Check the detail work on the coamings, the windscreens, the metal scuff plates at the pilot's heels and on the top longerons where the pilot climbs in and out. Sanitary!

Here's the main gear. Straight axle with bungee "suspension", mechanical disk brakes, and motorcycle tires.

A better shot of the main gear showing the torque tube with two links to the axle to keep the axle from rotating when brakes are applied. Safety cables secure the axle if the bungees go south. And, of course, the radiator for the water-cooled EA-82. What's that they say in Pietenpol circles, "real FBOs carry antifreeze"?

To see more on this airplane, continue on to The engine, the details, and that mysterious control lever... !