Brodhead Pietenpol Association

Original Posted By: "McNarry, John"
Thanks for your response on the airspeed/static question. I took alook at our local grass strip and found every possible combinationof airspeed/static designs on about 10 different planes. ExcellentIA and pilot Don Helmick over there told me to just unport thestatic fitting and run a probe out on the wing. Closed cabin planesare another story. Just about any diameter tubing will work too-I saw 1/8" up to 3/8" tubing. I'll do a calibration check anywhoafter she flies by timing myself back and forth over a knowndistance on our farm-square country roads. As long as I can passsome cars once in a while along the interstate I'll be happy. (w/a tailwind) Mike C.________________________________________________________________________________

Original Posted By: Michael D Cuy
On my Pietenpol I have the pitot tube located on the underside of thestarboard wing about two feet (40% of chord length) aft of the leadingedge. It is a 1/4 inch diameter tube emerging perpendicular to the sur-face of the wing for about 3 inches and then bent forward to face the oncoming air. It is patterned after the system used on Piper PA 15/17Vagabond airplanes and is not subject to getting rain, etc., in it.Originally I simply left the static port of the ASI open, but foundthat airspeed readings varied considerably depending on whether the front cockpit was occupied or not...or had a cover on it or not. Thisproblem was solved by extending a piece of plastic hose (1/4 inch ID)from the static opening of the instrument to the floor area ahead ofthe front seat, near the firewall.I'm sure that experimenting will indicate what is best for your par-ticular installation.Graham Hansen________________________________________________________________________________

Original Posted By: Michael D Cuy
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Original Posted By: Gary McArthur
>that airspeed readings varied considerably depending on whether the >front cockpit was occupied or not...or had a cover on it or not. This>problem was solved by extending a piece of plastic hose (1/4 inch ID)>from the static opening of the instrument to the floor area ahead of>the front seat, near the firewall.Graham- Interesting. Does your Piet have the backside of the instrument area open to air, or is there a wood door enclosing it ? I've got that area covered with a door/magnetic catch. Mike C. ________________________________________________________________________________

Original Posted By: grhans(at)freenet.edmonton.ab.ca
Michael D Cuy wrote:> > As long as I can pass> some cars once in a while along the interstate I'll be happy.> (w/a tailwind) Mike C. You wanna do what?! Maybe you know of some roads with STOP signs onthem, perhaps then you'll do some passing... :)Gary...________________________________________________________________________________

Original Posted By: JGreenlee(at)aol.com
>> As long as I can pass>> some cars I'll be happy.>> (w/a tailwind) Mike C.>>You wanna do what?! Maybe you know of some roads with STOP signs on them,perhaps then you'll do some passing... Gary...Gary- Did I mention that was passing cars w/ a tailwind AND during a descent ??! Ok-what if we level the field and try to pass some 1933 model cars ?? !! :)________________________________________________________________________________

Original Posted By: Michael D Cuy
Michael,Regarding your query, I never did get around to permanently closing offthe opening just in front of the instruments...and after nearly 27 yearsit is still the same as when I built it. One of these days I'll get around to doing it.But my experience with four different Pietenpols says that every one willbe different in some way. Temporarily covering the opening you mentionedwith a piece of cardboard didn't seem to make any difference on mine... which is why I'm in no hurry to make and install a proper cover. Theothers all had a cover in this location, but I never flew any of them witha passenger or front pit cover and can't say how it would have affectedthem. In any case, the system described works fine for me...likely because itkeeps the static opening in a place away from variable air currents; nearthe floor just aft of the firewall seems OK on mine. Must be a dead air region there.Graham________________________________________________________________________________

Original Posted By: grhans(at)freenet.edmonton.ab.ca
Michael,Another thing: You mentioned a magnetic catch on the door just ahead ofthe instruments. Will it affect your compass? Or is the compass locatedsomewhere else?Graham________________________________________________________________________________

Original Posted By: Michael D Cuy
> Gary- Did I mention that was passing cars w/ a tailwind AND during> a descent ??! Ok-what if we level the field and try to pass> some 1933 model cars ?? !! :)I dunno Mike, some of those 30's autos could move along at a right pertclip...Been following the airspeed pitot bit, also the "magnet" behind theinstrument panel, probably you will have answered the question of thecompass in some other message, but... where is the compass relative tothe magnet?Gary________________________________________________________________________________

Original Posted By: Gary McArthur
>I dunno Mike, some of those 30's autos could move along at a right pert>clip... Gary- good point ! Maybe I'll stick to just sightseeing >Been following the airspeed pitot bit, also the "magnet" behind the>instrument panel, probably you will have answered the question of the>compass in some other message, but... where is the compass relative to>the magnet? The magnet is small although is at the top curve of my inst.access door with a round brass plated 'pull-ring' on the outside-prettymuch in line with the compass. Geez.Seems when I had the fuse in the living room (yes) the compasspointed West correctly, and now that the plane is in the garage I'llhave too wheel it out tonight and do a four point check. Glad you guys mentioned this potential problem. If I see any abnormalerrors I'll just yank out that magnet and use velcro. (or like Red Greenon PBS- the handyman's secret weapon: duct tape. )________________________________________________________________________________

Original Posted By: Bill Talbert
Michael D Cuy wrote:> > Seems when I had the fuse in the living room (yes) the compass> pointed West correctly, and now that the plane is in the garage I'll> have too wheel it out tonight and do a four point check.> Glad you guys mentioned this potential problem. If I see any abnormal> errors I'll just yank out that magnet and use velcro. (or like Red Green> on PBS- the handyman's secret weapon: duct tape. )There shouldn't be any question, if you don't spread around a little"high speed tape" it won't fly... But then I thought you knew that inorder to achieve lift and proper weight & balance you NEED it...I imagine the magnet won't be a problem as long as you always headwest...Gary________________________________________________________________________________

Original Posted By: Fisherman Caye