Hatz Biplane Association

Hi Mark (Aerocraftsman) and all,

Very soon we will receive the flying wires (everything is finished except paperwork and will start the Rotec very soon) and are guessing about their tensioning! Somewhere we read, that you tensionned the wires to 650 lbs. To which gauge of wires does this apply, 5/16" front lift wires or twin 1/4" rear lift wires and the landing wires? What about the roll and tail wires?
We are fortunate to have a tensiometer on loan.
Your advice would most be appreciated!

Best regards

Hans & Sam, H.C.#78, Switzerland

I bought one of these from Steen and it's served me faithfully.

https://secure.steenaero.com/Store/site/product.cfm?id=ACC9E626-102E-BB20-180021F2FFEAABA4

The Stearman repair manual shows a devise made from 1" dia steel tube with a wooden dowell driven in and glued in place. A notch is then cut into the end. The finished tool is about 8" long. I made 2. One 6" and one 12". Works great.

Michael
N838MM

Jeff told me he uses the 2x4 with the notch in it as a wrench to turn the flying wires ..... Of course! Why did I not see this! ... duhhhhhhhh!
[i]
Okay I am going back to be a brunette ......[/i]

Happy Holidays everyone.
Keri-Ann

Open C...

Here is a reply from Jeff Shoemake, [u]hatzkit@gvtc.com[/u], of the Classic Hatz Plans. I proposed this question to him.

[quote]You are right, I get that question often. My answer is way less than analytical, but here goes. I think the most important issue is that the wire tension is balanced from one side to the other. Of course the amount of tension is important also. Gages are available to measure the tension. They work by measuring deflection in the wire. My suggestion is to use the “bubba” method, and just push or pull on the wires to get a feel for the tension. I constructed a very high tech tool for tightening the wires. It consists of a notch sawed into a 2 x 4 to fit on the wire. You can tell when the wires are getting tight. And just try to get them the same on both sides. I know that is a pretty weak answer but that is the way we do it and so far it seems to work. Let me know if I can help.

Merry Christmas
Jeff[/quote]

I am not sure what he means by this, so I am asking him to paint me a more visual picture of his process.

Blue skies,
Keri-Ann

I think 1200 lbs is way too much. We used 650 lbs.
Mark

I have the Holloway tension tool. I know what a Stearman needs to be (around 1200 pounds). But do not know if this number would be good for the shorter Hatz wires???

Michael
N838MM

[quote]That question comes up often on the forum. The general consensus tends to be to tune to an open "C".[/quote]

.... is that at 440 Hz?

Seriously, I found this that may help: [url]http://www.radialengine.com/flywire/index.html[/url]

Blue skies,
keri-Ann

That question comes up often on the forum. The general consensus tends to be to tune to an open "C". I take that to mean not too tight, not too loose. If they are too loose, the landing wires will be droopy when pulling a few G's. Too tight and you put unnecessary strain on the spars and struts. The main point , though, is to have all wires of equal length to be the same tone when plucked. *** Remember, this highly classified info is worth the cost. :lol: