Original Posted By: jmcnarry(at)techplus.com (John McNarry)
To Clay,My Piet has a wooden fuselage which has given good service formany (nearly 29) years, so there isn't much wrong with the woodstructure, provided it is hangared when not flying and is well-pro-tected with proper coatings together with good drainage and ven-tilation.During the mid 1970's, I started a second Pietenpol with the hopethat I could get at least one of my two teenage sons interested inbuilding it. I welded up a steel tube fuselage using the truss shownin the plans, and the only changes were the substitution of largertubing diameters in the forward fuselage and cockpit areas. Theresulting truss was very light and strong, but if I were to buildanotherI would design a new truss using the member placement of the woodfuselage (Pratt style truss) rather than the Warren style of the steeltubing version in the plans. Although slightly heavier, the Pratt trusskeeps the longeron length shorter between joint clusters and allowsone to pretty well duplicate the fitting locations ot the wooden fuse-lage.I had the fuselage on the gear, complete with engine and tail feathers(also of steel tubing), when I sold the project because (1) my boyswere interested in other things, and (2) I already had a Pietenpol. Thefellow who bought it finished it and it flew very well. Apparently,therewas water damage to the wings while they were removed and storedduring a period of inactivity. He has not had the time to make therepairsand the a/c is still in storage (dry, I hope).In summary, a steel tubing fuselage could be made lighter than a woodenequivalent, but by the time one adds seat support structure, attachmentclips for fairings, etc., a lot of time will be used up and some weightadded.The stark simplicity of the bare truss disappears once all this stuff isin place.Nevertheless, if I were to build another Pietenpol I would go the steeltubefuselage route using what I have learned over the years to keep itsimple andlight. I definitely would not recommend making the tail feathers ofsteel tub-ing even though my version was successful; it is, in my view, impossibletomake a steel tubing empennage as light and efficient as the wooden oneshown in the plans.Cheers, Graham HansenTo Clay,My Piet has a wooden fuselage whichhas givengood service formany (nearly 29) years, so thereisn't muchwrong with the woodstructure, provided it is hangaredwhen notflying and is well-pro-tected with proper coatings togetherwith gooddrainage and ven-tilation.During the mid 1970's, I started asecondPietenpol with the hopethat I could get at least one of mytwo teenagesons interested inbuilding it. I welded up a steeltube fuselageusing the truss shownin the plans, and the only changeswere thesubstitution of largertubing diameters in the forwardfuselage andcockpit areas. The resulting truss was very light andstrong, butif I were to build anotherI would design a new truss using thememberplacement of the woodfuselage (Pratt style truss) ratherthan theWarren style of the steeltubing version in the plans.Although slightlyheavier, the Pratt trusskeeps the longeron length shorterbetween jointclusters and allowsone to pretty well duplicate thefittinglocations ot the wooden fuse-lage. I had the fuselage on the gear,complete withengine and tail feathers(also of steel tubing), when I soldthe projectbecause (1) my boys were interested in other things, and(2) Ialready had a Pietenpol. Thefellow who bought it finished it andit flewvery well. Apparently, therewas water damage to the wings whilethey wereremoved and storedduring a period of inactivity. He has not had thetime to makethe repairsand the a/c is still in storage (dry, Ihope).In summary, a steel tubing fuselage could be madelighter thana woodenequivalent, but by the time one adds seat supportstructure,attachment clips for fairings, etc., alot of timewill be used up and some weight added.The stark simplicity of the bare truss disappearsonce allthis stuff is in place.Nevertheless, if I were to build another Pietenpol Iwould gothe steel tubefuselage route using what I have learned over theyears tokeep it simple andlight. I definitely would not recommend making thetailfeathers of steel tub-ing even though my version was successful; it is, inmy view,impossible tomake a steel tubing empennage as light and efficientas thewooden one shown in the plans.Cheers, Graham Hansen________________________________________________________________________________
Pietenpol-List: Steel tubing fuselages
Pietenpol-List: Re: Steel tubing fuselages
Original Posted By: Michael D Cuy
Graham It is always a pleasure to read your e-mails to the group.Thanks for sharing your experience with us. Sincerely John McNarry________________________________________________________________________________
Graham It is always a pleasure to read your e-mails to the group.Thanks for sharing your experience with us. Sincerely John McNarry________________________________________________________________________________
Pietenpol-List: Re: Steel tubing fuselages
Original Posted By: steve(at)byu.edu
Paul Prince in the UK is manufacturing steel fuselages for piets.Apparently, the original steel fuselage drawing didn't stand up to stressanalysis, and would have been difficult to alter to comply with the JAR/VLAregs (I think our rules in the UK are more restrictive than in the USA), soPaul has redesigned it using the latest computerised techniques.He uses CNC-cut square section to fabricate them, thereby simpifying thejoints.I understand that they make a lighter aircraft, and also add a littleextra legroom and vision (by lowering the passenger seat and moving thefirewall forward a couple of inches). There is also an access flap to easeentry into the front cockpit.Of course there are a lot of other benefits, including extra strength,4-point harness points, brackets, engine mount points etc. and mostimportantly, a build time reduction of, say, 18 months.The cost in the UK is about 4200 sterling - that gets a fully welded, epoxyetch-primed, PU topcoated and internally anti corrosion treated fuselage.It even comes in two bolt together parts to simplify transport and storage.Incidentally, in the UK, all welding has to be performed by a CAA certifiedwelder, whether for a homebuilt or otherwise. With a young family and not a lot of spare time, I think this is the routeI shall be following.Paul can be reached at:-Aviation MetalcraftUnit 28Enterprise HouseKing Edward StreetGrimsbyN. E. LincolnshireDN31 3JPEnglandT +44 1472 360 699F +44 1472 324 685And just for the record, I don't work for him - I just appreciate the workhe has put into this.LeoNottinghamshireEnglandleo(at)deadly.demon.co.uk________________________________________________________________________________
Paul Prince in the UK is manufacturing steel fuselages for piets.Apparently, the original steel fuselage drawing didn't stand up to stressanalysis, and would have been difficult to alter to comply with the JAR/VLAregs (I think our rules in the UK are more restrictive than in the USA), soPaul has redesigned it using the latest computerised techniques.He uses CNC-cut square section to fabricate them, thereby simpifying thejoints.I understand that they make a lighter aircraft, and also add a littleextra legroom and vision (by lowering the passenger seat and moving thefirewall forward a couple of inches). There is also an access flap to easeentry into the front cockpit.Of course there are a lot of other benefits, including extra strength,4-point harness points, brackets, engine mount points etc. and mostimportantly, a build time reduction of, say, 18 months.The cost in the UK is about 4200 sterling - that gets a fully welded, epoxyetch-primed, PU topcoated and internally anti corrosion treated fuselage.It even comes in two bolt together parts to simplify transport and storage.Incidentally, in the UK, all welding has to be performed by a CAA certifiedwelder, whether for a homebuilt or otherwise. With a young family and not a lot of spare time, I think this is the routeI shall be following.Paul can be reached at:-Aviation MetalcraftUnit 28Enterprise HouseKing Edward StreetGrimsbyN. E. LincolnshireDN31 3JPEnglandT +44 1472 360 699F +44 1472 324 685And just for the record, I don't work for him - I just appreciate the workhe has put into this.LeoNottinghamshireEnglandleo(at)deadly.demon.co.uk________________________________________________________________________________
Pietenpol-List: RE: Steel tubing fuselages
Original Posted By: Ted Brousseau
I'd say a savings of 18 months is a little bit much. I built my wholeairplane in 2.5 years. I bet I could build the wood fuse in less than amonth of part time work. It only took me two months on my first try. (80hours) Your mileage may vary.Steve Eldredge> Of course there are a lot of other benefits, including extra strength,> 4-point harness points, brackets, engine mount points etc. and most> importantly, a build time reduction of, say, 18 months.>________________________________________________________________________________
I'd say a savings of 18 months is a little bit much. I built my wholeairplane in 2.5 years. I bet I could build the wood fuse in less than amonth of part time work. It only took me two months on my first try. (80hours) Your mileage may vary.Steve Eldredge> Of course there are a lot of other benefits, including extra strength,> 4-point harness points, brackets, engine mount points etc. and most> importantly, a build time reduction of, say, 18 months.>________________________________________________________________________________