Old Information for New Pietenpol Pilots

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Cpirrmann
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Joined: Fri Dec 07, 2018 10:39 pm

Old Information for New Pietenpol Pilots

Post by Cpirrmann »

Hi All,
I have searched for the answers to these questions, but they are so old, they are in the archived posts and the info is incomplete or appears to be gone. I am new to the forum and it's possible I may not be navigating correctly, but I'll ask here and be grateful for any info, pointers or links.
1. Does anyone have any suggested checklists for preflight, flight regime and condition inspections? I can develop them on my own, especially the flight regimes (takeoff/landing/emergency/ etc.) but I don't want to miss something on a preflight or condition inspection peculiar to these planes because of ignorance.

2. Are there any values or recommendations on the cable tensions both controls and bracing?

3. How far back can the wing safely be moved?

Thanks in advance for any help.
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taildrags
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Re: Old Information for New Pietenpol Pilots

Post by taildrags »

Cpirrman: good questions, and probably not a bad time to re-post some of these things. First of all though, where are you located? You may find that you have resources that are close to you, such as flying Piets and other builders. Now to your questions. I'm no expert, but I'm happy to share what I've found in my time on this list and in the Piet world.

1. Most Piets are very simple aircraft, so cockpit checklists are either very brief or are nonexistent. In most of my flying in varied aircraft over the years, even the mnemonic checklists are more than what I need for my Piet, which has no electrical system, mixture control, or trim adjustment. At runup, the "CIGARS" mnemonic on mine goes like this:

C ontrols- correct displacement, full and free travel; note that with a passenger, the travel of the pilot's feet on the rudder bar may be hindered by the front seatbelt or the passenger's clothing;
I nstruments- check oil temp, oil pressure, and general position of the needles on the flight instruments; set altimeter;
G as- fuel valve on, check float indicator for fuel quantity;
A ttitude- (there is no trim to adjust on my airplane);
R unup- (after oil is warmed up) check RPM drop on mags and carb heat; everything in the green;
S afety- seat belts and shoulder harnesses secure; nothing loose in the cockpit; ready for radio call and traffic check.

On downwind in the pattern, the "GUMPS" mnemonic goes like this:

G as- selector on good tank (only one tank on my airplane!);
U ndercarriage- (gear on my airplane is welded in the down-and-locked position);
M ixture- full rich (no mixture control on my airplane);
P rop- in the high speed position (no prop control on my airplane);
S afety- seat belts and shoulder harnesses secure; ready for radio call and traffic check prior to power reduction for turn to final.

There is no standardized operations manual, condition inspection checklist, weight and balance spreadsheet, or other such information on the Air Camper since no two are alike, but several versions have been shared on this list and I've attached the ones that I've seen posted and that I have downloaded and edited to suit my own airplane. The ones attached are the more generic documents that are not original with me.

2. You will find many discussions on cable tensioning as you search the archives. There are two general classes of aircraft cables on the Piet: the standing rigging and the control cables. The general consensus for the standing rigging (wing bay drag/anti-drag brace wires, cabane bracing, wing lift strut X-braces, tail brace wires) is that they should 'twang' when plucked, but they should not be over-tensioned. If they only give a dull thump when plucked, they may be too loose. If they are so tight that you can barely pluck them or they give a 'twing' instead of just a nice 'twang', you'll probably need to slack them off. As for the control cables, there is no need to put them in a high state of tension, just take the slack and slop out of them. Be aware, though, that the cables that pull the elevators down on most Piets (the lower cables) will lose tension and go slightly slack with full forward stick (elevators down), and when the elevators are down like that, the upper cables may contact the leading edge of the horizontal stabilizer. This is OK, and you can convince yourself of that by placing the stick and elevators in the neutral position. In that position, both the upper and lower elevator cables should have about the same tension on them... no slack, but not super tight. The other cables that are back there are the tailwheel steering cables and those should be tight but not so tight that they're compressing the tailwheel springs. Snug, no slack. Some builders/pilots prefer that there be just a little slack in their tailwheel cables so the ground steering isn't too twitchy, but personally, I like to have tailwheel responsiveness on the ground... no hesitation, no slack.

3. How far back the wing can safely be moved aft is something I've never seen definitively stated on this list, but numerous Piets are flying with the wing shifted as much as 4" aft. There are three problems with continuing to shift the wing aft more than that. One, if you have to do more aft shifting, you probably have a bigger weight & balance problem than you should be trying to correct in this way. Run a new W&B and look elsewhere for moving the CG forward. Two, as you shift the wing aft, the aileron control cables leading down to the control stick bellcrank also move aft and may begin to contact things behind the instrument panel. Three, as you shift the wing aft, you're making it more difficult for the pilot to get into the cockpit. Most Piets have a centersection 'flop' panel to help with this, but it's definitely a consideration since the wing not only moves aft, it also moves down.
Attachments
PietenpolOperationManualWorking.doc
(1.38 MiB) Downloaded 608 times
Pietenpol_Air_Camper_Annual_Condition_Inspection_Checklist.doc
(43 KiB) Downloaded 435 times
weightandbalancespreadsheet(1).xls
(20 KiB) Downloaded 440 times
Cpirrmann
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Joined: Fri Dec 07, 2018 10:39 pm

Re: Old Information for New Pietenpol Pilots

Post by Cpirrmann »

Hi Taildrags,
Thank you very much for taking the time to compose such an extensive reply. That is all very useful and the information I was looking for. Again, thank you.
Brian Amato
Posts: 112
Joined: Fri Aug 31, 2018 9:23 am

Re: Old Information for New Pietenpol Pilots

Post by Brian Amato »

Hey Oscar....my lame-o computer, or me....can't seem to open any of those docs. What do I need?
Brian
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taildrags
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Re: Old Information for New Pietenpol Pilots

Post by taildrags »

Brian; those are PDF documents... Portable Document Format... you need Adobe Acrobat Reader to open and view them. It's a free download, here: https://get.adobe.com/reader/
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taildrags
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Re: Old Information for New Pietenpol Pilots

Post by taildrags »

Whoa... wait a minute. Those show up as PDFs but the first two are actually Word documents that any word processing program should be able to open. Microsoft Word is the most available such program. The W&B spreadsheet is an Excel spreadsheet, xls format, that you can open with any spreadsheet program. Microsoft Excel is the most available.
Bill Church
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Joined: Fri Feb 24, 2017 8:48 am

Re: Old Information for New Pietenpol Pilots

Post by Bill Church »

In case anyone wants them, here are PDF versions of those three documents.
Naturally, the weight and balance spreadsheet loses all of it's functionality, when converted to a PDF document.

Bill C.
Attachments
weightandbalancespreadsheet.pdf
(25.06 KiB) Downloaded 321 times
PietenpolOperationManualWorking.pdf
(422.2 KiB) Downloaded 340 times
Pietenpol_Air_Camper_Annual_Condition_Inspection_Checklist.pdf
(80.04 KiB) Downloaded 311 times
Brian Amato
Posts: 112
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Re: Old Information for New Pietenpol Pilots

Post by Brian Amato »

Great...I CAN open PDFs
Thanx
VincentDunn
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Joined: Tue Nov 21, 2017 6:45 pm
Location: Salem, OR

Re: Old Information for New Pietenpol Pilots

Post by VincentDunn »

Cpirrman,
I recently strung my drag/anti drag wires in the wings. My EAA Tech Counsilor, the venerable Ernie Moreno, advised me that the tension should be 60 lbs. I borrowed a cable tensioner to get exactly that value on each wire. It was easy too. Hope this helps. Vincent Dunn.
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taildrags
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Re: Old Information for New Pietenpol Pilots

Post by taildrags »

If you know of someone who has a sailboat, or if there is a sailboat shop in your area, they use a cable tensioning gauge to set up the standing rigging on the boat and you should be able to either borrow it to check your cables, or perhaps give them a tour of your shop if they'll bring the tensioning gauge over to help you with it.
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