REFLECTOR: Fw: Sparrow strainer - I'm confused...

John Dibble aminetech at bluefrog.com
Wed Sep 19 13:24:02 CDT 2012


Is there some safeguard to prevent the screws from loosening and the ss 
moving to a position beyond what the spring can handle?

John

On 9/19/2012 1:02 PM, Andrew Ellzey wrote:
>
>
>     Geoff,
>     Two photo's attached.
>     Andy
>
>         *From:* Geoff Gerhardt <geoff.gerhardt at gmail.com>
>         *To:* Andrew Ellzey <ajlz72756 at yahoo.com>
>         *Sent:* Tuesday, September 18, 2012 9:34 AM
>         *Subject:* Re: REFLECTOR: Sparrow strainer - I'm confused...
>
>         Andrew,
>
>         I was thinking of doing something similar - please send me a
>         photo when you get a chance.
>
>         Thanks.
>
>         Geoff
>
>         On Tue, Sep 18, 2012 at 10:21 AM, Andrew Ellzey
>         <ajlz72756 at yahoo.com <mailto:ajlz72756 at yahoo.com>> wrote:
>
>             Geoff,
>             Cutting the Sparrow Strainer off and reattaching it at a
>             different angle seems a bit harsh. I made my SS adjustable
>             by potting a 10X32 nut plate inside each end of the
>             airfoil. So the Airfoil is then held in place on by two
>             10X32 screws. I am not flying yet, so I don't know if my
>             aircraft even needs an adjustable SS. But from all of the
>             talk of trim problems on the reflector, over the years, I
>             thought that I would be proactive and make my SS
>             adjustable. I will install mine per the manual, but if
>             needed, I can change the angle of attack or even invert my
>             SS airfoil as some have suggested. I also think with a
>             little trial and error, I should be able to adjust the SS
>             depending on my aircraft CG calculations, due to passenger
>             loading. This may be wishful thinking on my part, due to
>             the small size of the Sparrow Strainer. I can send you a
>             photo latter today if you think this option will work for you.
>
>                 *From:* Geoff Gerhardt <geoff.gerhardt at gmail.com
>                 <mailto:geoff.gerhardt at gmail.com>>
>                 *To:* Velocity Aircraft Owners and Builders list
>                 <reflector at tvbf.org <mailto:reflector at tvbf.org>>
>                 *Sent:* Saturday, September 15, 2012 7:45 PM
>
>                 *Subject:* Re: REFLECTOR: Sparrow strainer - I'm
>                 confused...
>
>                 Guys,
>
>                 Thanks for all the suggestions.  What I think I may do
>                 is cut the arms that join the SS to the elevator and
>                 then re-connect them with the SS airfoil at a lower
>                 angle of attack to reduce the speed-induced up-trim.
>
>                 Today, I had a great flight.  I made some changes to
>                 my cooling plenums that reduced temps in cylinder #3
>                 (I'll describe these changes in another email), so I
>                 was able to do a pretty aggressive climb to 10,000'.
>                  I was going to do flutter testing, but when I dove to
>                 gather speed, I found that too much stick pressure was
>                 req'd to go above 180kts to properly assess flutter.
>                  I could not trim it so that I could take my hand off
>                 to give the stick a whack because I had to keep down
>                 pressure to stop from climbing out of the dive.  All
>                 control surfaces were fine to 180kias, but I think
>                 I'll need to address the aerodynamic trim to go
>                 higher.  Or, is it okay to have stick pressure on when
>                 doing flutter testing?
>
>                 Geoff
>
>                 On Sat, Sep 15, 2012 at 11:20 AM, Terrence Miles
>                 <terrence_miles at hotmail.com
>                 <mailto:terrence_miles at hotmail.com>> wrote:
>
>                     Geoff,
>                     Over the past 10 years or so, the sparrow strainer
>                     debates  and opinions (which are always
>                     fascinating to me) and the "running out of trim"
>                     issue come up on a regular basis.  Geoff, you are
>                     hardly the first in the test flight phase to
>                     wrestle with this.  I have the RGXL-5 with a LY
>                     IO540.  I weigh 150 pounds.  Empty wgt she is 1928
>                     lbs at 136.4   I know other light weight pilots
>                     like me that fly with ballast on the floor by the
>                     right seat.  I don't because I have two nose
>                     mounted Odyssey batteries. XC by myself with 70
>                     gal of fuel and the usual crap in the back seat
>                     area (125+ lbs) I am at a CG of 130ish.  With a
>                     185 lb copilot it goes to 128.3 or so if anybody
>                     out there is considering 2 nose batts be aware of
>                     that limit.   Because I am short I have the arm of
>                     my seat is 79 inches.  The copilot is at 83 inches.
>                     I am not suggesting this for others, but with
>                     advice like you are seeking right now, and more
>                     than several conversations with Malcolm Collier
>                     and others, I decided to do this:  The factory
>                     trim spring didn't fit due to insufficient space
>                     behind the panel without major changes.   Also the
>                     stock elevator trim motor throw was too short.  I
>                     have a speed brake trim motor running my elevator
>                     trim which is longer by an inch or two.  Yes, I
>                     have to watch for fractures in my sawed off,
>                     reduced curve spring, but  I don't run out of trim
>                     no matter wgt, CG, or speed.
>                     Terry
>                     *From:*reflector-bounces at tvbf.org
>                     <mailto:reflector-bounces at tvbf.org>
>                     [mailto:reflector-bounces at tvbf.org
>                     <mailto:reflector-bounces at tvbf.org>] *On Behalf Of
>                     *Richard J. Gentil
>                     *Sent:* Friday, September 14, 2012 10:31 PM
>                     *To:* geoff.gerhardt at gmail.com
>                     <mailto:geoff.gerhardt at gmail.com>; Velocity
>                     Aircraft Owners and Builders list
>
>                     *Subject:* Re: REFLECTOR: Sparrow strainer - I'm
>                     confused...
>                     Geoff,
>                     To help solve the issue I just cut my sparrow
>                     strainer in half.
>                     Richard
>
>                     Sent from my iPhone 4 Classic
>
>                     On Sep 14, 2012, at 10:01 AM, Geoff Gerhardt
>                     <geoff.gerhardt at gmail.com
>                     <mailto:geoff.gerhardt at gmail.com>> wrote:
>
>                         Guys,
>                         As I'm flying more, I'm getting a better feel
>                         for the plane and discovering little issues.
>                          I noticed yesterday that when I really dangle
>                         (i.e. >160kts), I run out of down trim.  I
>                         guess I wasn't paying attention before, but as
>                         I speed up, I need to keep adding down trim -
>                         I thought that's what the sparrow strainer was
>                         for.  As speed increases, the canard is
>                         generating more lift, so the sparrow strainer
>                         trims the nose down so that less trimming is
>                         needed for speed changes.  But then, I was
>                         looking at the way the sparrow strainer is
>                         mounted and it looks like it would do just
>                         the opposite.  As speed increases, the sparrow
>                         strainer will be pushed down, adding trim up!
>                          I have my aerodynamic trim installed as per
>                         factory instructions.  I've heard of some who
>                         install it upside down, which to me sounds
>                         like how it should be installed.  I have a
>                         feeling that if I remove it I'd have to trim
>                         less with speed changes.  Unfortunately, I
>                         used some pretty aggressive silicone glue to
>                         put it on and I'm afraid I'll make a mess of
>                         it taking it off.
>                         Any thoughts on the effectiveness/correct
>                         installation of aerodynamic trim?
>                         Here's now I have mine installed:
>                         http://thegerhardts.com/velocity/?p=491
>                         Geoff
>
>                         _______________________________________________
>                         To change your email address, visit
>                         http://www.tvbf.org/mailman/listinfo/reflector
>
>                         Visit the gallery! www.tvbf.org/gallery
>                         <http://www.tvbf.org/gallery>
>                         user:pw = tvbf:jamaicangoose
>                         Check new archives: www.tvbf.org/pipermail
>                         <http://www.tvbf.org/pipermail>
>                         Check old archives:
>                         http://www.tvbf.org/archives/velocity/maillist.html
>
>
>
>                     _______________________________________________
>                     To change your email address, visit
>                     http://www.tvbf.org/mailman/listinfo/reflector
>
>                     Visit the gallery! www.tvbf.org/gallery
>                     <http://www.tvbf.org/gallery>
>                     user:pw = tvbf:jamaicangoose
>                     Check new archives: www.tvbf.org/pipermail
>                     <http://www.tvbf.org/pipermail>
>                     Check old archives:
>                     http://www.tvbf.org/archives/velocity/maillist.html
>
>
>
>                 _______________________________________________
>                 To change your email address, visit
>                 http://www.tvbf.org/mailman/listinfo/reflector
>
>                 Visit the gallery! www.tvbf.org/gallery
>                 <http://www.tvbf.org/gallery>
>                 user:pw = tvbf:jamaicangoose
>                 Check new archives: www.tvbf.org/pipermail
>                 <http://www.tvbf.org/pipermail>
>                 Check old archives:
>                 http://www.tvbf.org/archives/velocity/maillist.html
>
>
>
>
>
>
>
>
> _______________________________________________
> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
>
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.tvbf.org/mailman/private/reflector/attachments/20120919/f8a12964/attachment-0001.html>


More information about the Reflector mailing list