Original Posted By: steve(at)byu.edu
Subject: Pietenpol-List: Round vs. Streamlined>Dean Dayton wrote:>>Do they really have to be streamlined ?>>Dean->for his lift struts and they look good. I think the streamlining>is more for the eye than for drag reduction......especially on>something as draggy as a Piet. I've heard of guys using balsa wrapped>w/ dacron, foam, etc. to fair the tubes.>>Mike C.>>________________________________________________________________________________
Pietenpol-List: Round vs. Streamlined
Pietenpol-List: Round vs. Streamlined
Original Posted By: "BELLISSIMO, DOMENIC"
Dean Dayton wrote:Dean- for his lift struts and they look good. I think the streamliningis more for the eye than for drag reduction......especially on something as draggy as a Piet. I've heard of guys using balsa wrappedw/ dacron, foam, etc. to fair the tubes. Mike C. ________________________________________________________________________________
Dean Dayton wrote:Dean- for his lift struts and they look good. I think the streamliningis more for the eye than for drag reduction......especially on something as draggy as a Piet. I've heard of guys using balsa wrappedw/ dacron, foam, etc. to fair the tubes. Mike C. ________________________________________________________________________________
Pietenpol-List: Re: Round vs. Streamlined
Original Posted By: Michael D Cuy
This round tube strut then wrapped with fabric over balsa is how I did mystruts for my '24 Dormoy 'Tub. One heck of a lot cheaper than streamlinedtubing...could be done with Gary Price's rectangular tubing methodtoo..........Earl Myers-----Original Message-----
This round tube strut then wrapped with fabric over balsa is how I did mystruts for my '24 Dormoy 'Tub. One heck of a lot cheaper than streamlinedtubing...could be done with Gary Price's rectangular tubing methodtoo..........Earl Myers-----Original Message-----
Pietenpol-List: Re: Round vs. Streamlined
Original Posted By: Ian Holland
There is one advantage to using some sort of streamling. The dragreduction may not have a great effect on the overall speed of the plane,but they do increase the force on the tubes. In my case, there is 9' ofstrut tubing with about a 5.5' span unsupported (by a jury strut). Undercompression, the main failure mode is buckling with a tube of thisgeometry so if the tube already has a buckling load (imposed by the drag)it's that much more prone to failure. Streamlined tubing is very rigidfore and aft due to it's shape and is also under less load. I plan on countering some of the fore/aft loads by adding a cross memberto the 2 jury struts to form an "N" shape. There is a forth strut thatspans the two main struts at the jurry fittings.However, I did notice that Chris Heintz has used round struts on hislatest creation, the CH-801. THis is the 4 place, 180 hp followon to theCH-701. If an airplane this big and ugly...err..heavy can get away withround tubing, ours should be a snap.KenOn Tue, 11 May 1999, Michael D Cuy wrote:> Dean Dayton wrote:> > Dean- > for his lift struts and they look good. I think the streamlining> is more for the eye than for drag reduction......especially on > something as draggy as a Piet. I've heard of guys using balsa wrapped> w/ dacron, foam, etc. to fair the tubes. > > Mike C. > ________________________________________________________________________________
There is one advantage to using some sort of streamling. The dragreduction may not have a great effect on the overall speed of the plane,but they do increase the force on the tubes. In my case, there is 9' ofstrut tubing with about a 5.5' span unsupported (by a jury strut). Undercompression, the main failure mode is buckling with a tube of thisgeometry so if the tube already has a buckling load (imposed by the drag)it's that much more prone to failure. Streamlined tubing is very rigidfore and aft due to it's shape and is also under less load. I plan on countering some of the fore/aft loads by adding a cross memberto the 2 jury struts to form an "N" shape. There is a forth strut thatspans the two main struts at the jurry fittings.However, I did notice that Chris Heintz has used round struts on hislatest creation, the CH-801. THis is the 4 place, 180 hp followon to theCH-701. If an airplane this big and ugly...err..heavy can get away withround tubing, ours should be a snap.KenOn Tue, 11 May 1999, Michael D Cuy wrote:> Dean Dayton wrote:> > Dean- > for his lift struts and they look good. I think the streamlining> is more for the eye than for drag reduction......especially on > something as draggy as a Piet. I've heard of guys using balsa wrapped> w/ dacron, foam, etc. to fair the tubes. > > Mike C. > ________________________________________________________________________________