Today's Message Index:
----------------------
1. 07:26 AM - Re: NTSB report. (sdthatcher)
2. 06:46 PM - Re: XL wing concerns (Ron Lendon)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: NTSB report. |
Although I certainly feel cables should be tight (within reason), especially in
light of having my cables loosen during a 600 mile flight last October, a loose
cable is less likely to vibrate than a tight one (cable frequency decreases
as cable tension decreases). A completely slack cable will generally never see
any induced vibrations (it's natural frequency is below any rotating equipment).
However, the loose cable may result in a potential flutter of the ailerons
which is less likely with a tight cable. It may have been my imagination, but
while flying over the mountains of NC last October with extremely loose cables
at a speed of about 100 mph, I was sure I noticed some small vibrations in
the ailerons. What alerted me to the looseness of the cables in flight was the
fact that I could move the stick about 1/2 inch either side of center without
any force being exerted on the stick. When I landed in Andrews, NC and checked
the cables, I noticed the balance cable was completely slack (it could be
moved up and down about 6-8 inches). I won't get into why the cables became
loose at this point since Ihab and I have discussed the geometry of the wing,
cable displacement, initial tightness, rib bending, etc., etc., in order to determine
the cause to no avail. If I discover a reason, I'll let everyone know.
But in the meantime, just make sure your cables are tight, just not too tight.
larry(at)macsmachine.com wrote:
> Hi Gary,
> ...It is the unrestrained
> weight of a cable that is considered a "player" in the flutter
> discussions and
> that's any cable with low enough tension to swing freely between its
> ends. In most cases, you cannot get that with 25 to 30 lbs.
> Easy enough to feel the difference if you think about it. A tension
> gage might be more useful to avoid over tightening as loose is easy
> to diagnose.
>
> Larry McFarland 601HDS at www.macsmachine.com
>
> Gary Gower wrote:
>
> > I am still building my 601 XL , now finishing the Fuselage, will
> > start the wings soon...
> >
> > I will like to hear some good answers about simple questions:
> > What will be more dangerous? To over tight the cables? Or to have
> > the cables just a little loose (in the lower side of the tension
> > specs)?
> >
> > Just wondering before I need a cable tension meter :-)
> >
> > Saludos
> > Gary Gower
> > Flying from Chapala, Mexico
> > 701 912S 230 hrs...
> > 601XL Jab 3300 Tail done, fuselage almost ready, wings next.
> >
> >
> >
> >
>
--------
Scott Thatcher, Palm Beach Gardens, FL
601XL with Corvair, Registered as E-LSA
N601EL, EAA203 25 hours and climbing.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=222567#222567
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: XL wing concerns |
ronpollock(at)gmail.com wrote:
> Thanks Ron. I'm plans building a 701 now so know the drill. Just took a liking
to the 601 and ran into a bunch of controversy I'm trying to sort out. Add to
that the new model and trying to sort that out. Guess my real question was
whether some here, if starting now, would build from 650 plans. I've gotten feedback
that they are almost mix & match.
>
> I wasn't asking if anyone had regrets or would go non-Zenair. But I'm happy to
hear those happy with their 601s as from my position a little extra confidence
is required to start on.
>
> Ron in L.A.
>
> --
Ron,
The XL is a well designed structure. Quite strong in my opinion and I have a bit
of experience in destroying structures, it was part of my job at Chrysler Engineering
back in the 70's.
The feeling I get from talking to the Heintz's is it, the 650, is just slight changes
from the several models they build worldwide to reduce the component count
and make a better plane. Either XL or 650 are pretty much the same from what
I see.
Much of the XL controversy sounds like our American press, full of supposition,
conjecture, and opinion. As far as any consistent contributing factors there
appears to be none currently.
--------
Ron Lendon, Clinton Township, MI
WW Corvair with Roy's Garage 5th bearing
Zodiac XL, ScrapBuilder ;-)
http://www.mykitlog.com/rlendon
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=222721#222721
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|