Manage my Membership

July 13
Pre-Oshkosh Prep

With Oshkosh — er, EAA AirVenture at our doorstep, work on the Six in '06 doesn't stop. Two recent trips to maintenance facilities have brought additional improvements to the airplane, so let's touch on them.

MAC return visit
After I flew the Six to the National Cherokee Fly-In at the Grand Glaize-Osage Beach (Missouri) Airport (K15), it was time to go back to Muncie Aviation Company (MAC) to fix some avionics glitches. In a restoration job of this magnitude, you'd expect some.

One had to do with the J.P. Instruments EDM-930 engine gauge display. The tachometer part of this very nice display had developed an annoying habit of fluctuating like mad. I mean, you'd be cruising along, and then see the tach go to 10,000 rpm, then 13,000 rpm, then 3,000 rpm, back and forth. Wow! That gets your attention. The 930's "master caution" display (just above the Castleberry attitude indicator) sounded the alarm for a prop overspeed in red letters — as it's supposed to do — and the "percent power" portion of the 930's display would reach some astounding values, like 300-percent power.

Of course, the propeller was right on speed, so there was no real cause for alarm. But some troubleshooting by MAC's Ken Talhelm revealed that the tach generator wiring was inadequately shielded. Stray voltage was escaping, and this caused the tach display to go wonky. Shielding was added, and the problem went away.

J.P. Instruments also had to recalibrate the 930's fuel totalizer parameters to reflect the airplane's 84-gallon capacity. The unit came from the factory programmed with the standard, 50-gallon fuel capacity. What this meant was that as I flew along, I received false "Lo Fuel" advisories on the master caution and 930 displays. The 930 "thought" I was about to run on fumes — even though I had as much as two or more hours' worth of fuel left! Anyway, a customized chip was programmed by J.P. Instruments, and as soon as it's installed, those "warnings" will go away. (J.P. Instruments will not allow this chip to be reprogrammed in the field; it must be returned to the factory.)

Go ahead, make fun of my E6B! Now you know why I still carry one. The old circular slide rule is still a good way to keep track of your fuel status. Some would say the E6B is the method of last resort. I would argue just the opposite. All this fancy equipment is great, but what if your fuel totalizer fails? You did write down your engine start and takeoff times, yes?

Then there was the pitch trim indicator. Like virtually all old Pipers, the indicator on the Six in '06 quit working. You could run the trim up and down, and that tiny, flimsy pointer would just stay put. The same thing happened in 2004 with the Win-A-Twin Comanche. Anyway, Muncie's Steve Larrimore put his crew to work, and now the indicator indicates. Now I'll be more certain of my pitch trim setting for takeoffs. Thanks Steve and crew!

Oh, and the same crew fixed the left brake (it failed too — for the second time) and the flap handle.

The flap handle problem was a very serious one, in my opinion. Here's how the problem manifested itself:

• During the prelanding checklist, I'd pull on the flap handle and set the first notch of flaps at the key position. The handle's pawl clicks into the flap mechanism's teeth. Fine, so far.
• On short final, with the field made, I'd pull on the flap handle for the second notch of flaps. The pawl engages, but after a second or so, it pops out, the flap handle slams down, and the flaps instantly retract to the first notch. Not good!
• On one occasion (the approach to K15), this sudden retraction caused a pitch-down moment at about 200 feet agl. Initially, I tried to reset the flaps to the second position — but the pawl wouldn't re-engage. Should I hold the flaps at the second notch with one hand while flying with the left, leaving the power be? Go around, with the field made? No way! I released the handle and let the flaps go down to the first notch, then completed the landing that way. It was scary for a second, so I wanted this fixed once and for all.

Larrimore's crew fixed the pawl, then let me know that this kind of failure can be common on older Pipers. So beware, those of you flying them! The wear of 40 years can take its toll on the flap mechanism.

Aft-facing seats
For the Six in '06's club seating to be approved, it was necessary for us to take some extra procedural steps. You see, soon after buying the Six in '06, we learned that the airplane's club seating setup wasn't properly documented.

To set the matter right, we needed three things:

• Approval for a club seat installation (pre-1978 Cherokee Sixes came only with forward-facing seats). This would mean a one-time approval based on a signoff by a designated engineering representative (DER), who is empowered by the FAA to make these sorts of modification approvals. The approval is based on a set of installation drawings and a parts list developed by the DER, and the DER's demonstrated expertise and background.
• Correct Piper/New Piper parts that conform to the specifications. This meant locating aft-facing seats, as well as the floorboard and other hardware that go with them. Aft-facing seats are stronger because their backs must be able to withstand more G-forces in the event of a sudden deceleration (i.e., an accident).
• Someone who could install the DER-approved seats.

Enter Wentworth Aircraft Inc. of Minneapolis, Minnesota (www.wentworthaircraft.com; 800/4WENTWORTH). Wentworth is a huge used-parts dealer, headed by Steve Wentworth. Yes, to be perfectly blunt, some would call Wentworth Aircraft a junk yard. But where else can you find out-of-production parts in a world where the average age of the general aviation airplane is 30-plus years old?

Anyway, Steve found and shipped us a set of aft-facing seats, which happen to be rare as hen's teeth these days. The mounting hardware and floorboard were also included in the package.

For a DER, we called on Harold Kosola, of Kosola and Associates. Ironically, Harold worked at Piper in the time when the Six in '06 was built. Back then, he said, there were plans — and drawings — to put club seating in early Cherokee Sixes. Piper dropped the idea, but Kosola was familiar with the Piper-approved method of installing aft-facing seats. Harold will generate an FAA Form 8110-3 to officially approve the new installation. An 8110-3 is called a "Statement of Compliance with Federal Aviation Regulations," and it has the effect of a supplemental type certificate, even though it's a one-time approval for one specific airplane.

To install the seats, we went to Air Mod of Clermont County Airport (I69) in Batavia, Ohio, an interior design and restoration shop headed up by Dennis Wolter. Air Mod has worked on several AOPA sweepstakes projects in the past and is known for the thoroughness and uniformly high quality of its work. Wolter is documenting the work and will install the new seat hardware. After that, the seats will go to the Six in '06's interior shop — Aircraft Interiors of Memphis — for their custom leather coverings.

Corrosion control
Air Mod is doing a couple other jobs on the Six in '06. New Piper came through again — this time with a seat-belt/shoulder harness kit for the cockpit seats — and Air Mod will be installing them. Back in 1967, these airplanes came with lap belts only. That's not good enough for an AOPA Sweepstakes airplane. Many thanks to New Piper's Matt Bourvic, a key player in the New Piper dealer support section. And thanks Matt, too, for the new floorboard! (Wentworth's floorboard was on its last legs.)

Air Mod specializes in corrosion control. This is an issue as big as it is neglected, but the company goes the extra mile in detecting and correcting corrosion issues. If you bring an airplane for Air Mod to upgrade, it will automatically get a corrosion search-and-destroy procedure, followed by a zinc chromate treatment to keep any more corrosion at bay for the next decade or two.

The Six in '06, it turns out, had very little corrosion. What there was, was of the light, surface variety. This was addressed, and so was the removal of an ancient bird nest that was located beneath the aft baggage flooring. The bird, which may have been an archaeopteryx, had long left the scene.

See you at AirVenture
The Six in '06's next trip is to Wittman Regional Airport (OSH) in Oshkosh, Wisconsin, on or about July 21. There, the ship goes on display for the entire week (July 24-30) of the Experimental Aircraft Association's annual EAA AirVenture Fly-In.

The airplane will be parked in front of AOPA's Big Yellow Tent, just inside the main entrance, over on the left side after you go through the gate. I'll be there, and so will the rest of the AOPA staff. We'll answer your questions, shoot the breeze, and give you a firsthand look at this great airplane. You won't see the new paint job yet (Dial Eastern States Aircraft Painting, Inc. of Cadiz, Ohio, will be doing this immediately after AirVenture), nor the new interior (Aircraft Interiors will do that in September), but you'll see a heckuva good panel and very pretty engine overhaul. See you there! And don't forget to check this Web site for updates, photos, and videos.