VG's on my Moose

[Charlie Starr]

Some weeks ago, I made an inquiry on this site for information or experiences on installation of VG's on the SR or Moose. I received a number of replies that were most helpful and informative. Thanks to you all. In the past several days, I've seen a bit of discussion on VG applications to both the Rebel and Elite. I spent the better part of the past weeks applying and testing VG's on my SR and thought I'd share my experiences for what they may be worth.

I tried the "Hall" kit (available direct from Hall or from ACS) rather than the Micro kit - primarily because of price; however, the fact that they (the Hall kit) are double sided VG's rather than 'single-angled' (making installation about half as easy) also entered into my decision. Hall's are probably somewhat less expensive because (I believe) they are intended for the experimental field rather than the certified market.

The manufacturer makes some recommendations as to percent of chord locations as well as lateral spacing distances. I followed his recommendations - though had to make several very slight changes to avoid existing rivet lines. He assured me that this was not a problem. Even so, I tried several different slight location changes (right - left; fore - aft). Frankly, I could see no difference between any of these small changes and ended up back with my original placement when attaching permanently, but this still moved some slightly from the exact recommendations, missing the rivet lines. I used the supplied tape for temporary installation. My only objection to this tape was that it stuck so good that I had to strip and repaint several of the VG's because the tape pulled some paint off during removal (probably my paint technique was partly to blame). Final (permanent) installation was made with loctite.

I ended up using 19 VG's per wing (38 vertical projections each side) and 9 on each horizontal stab (18 vertical projections per side).

The test results: I couldn't believe I was flying the same airplane. Power off stalls are an almost non-event; the nose can be held at an improbable high deck angle, with almost no air speed showing. GPS readouts gave speeds in the mid - upper 40's (knots). The nose could be held there indefinitely and other than the IVSI showing about 400 fpm decent and a slight buffet, it was difficult to believe that it had stalled. Ailerons were still somewhat effective and the rudder was fully functional, as usual, during a stall. Power on stalls and stalls with flaps, produced a definite break and a slight tendency to fall off on a wing. Indicated speeds were almost not readable and the GPS tests averaged in the low 40's. Rudder was still effective. In all stalls, standard recovery techniques of relaxing back pressure and power easily exited the stall. All initial tests were with only myself on board and approximately 80 gal. of fuel - about 300+# below MGW.

In normal flight, aileron control was noticeably better, though improvement would still be desired (I do not have the spade kit). Landing flare capability was also noticeably improved, and 3 point flare and landing also noticeably improved, with much better elevator authority. There was no noticeable improvement in cruise speed, though initial climb performance did seem slightly improved.

The only objectionable characteristic (if you can really call this an objectionable characteristic) seemed to be that more precise speed control (good technique) on final was important; otherwise the landing run would be longer than usual due to the tendency to float rather than to quit flying and land. Ease of washing the wings and care with a fuel hose will also be issues.

Bottom line - - I am quite happy with the results and in the improvements that these VG's have produced. If anyone wants more detailed information on my experiences, please feel free to contact me off-line at cws1932@cox.net also would be happy to talk by phone.

Charlie Starr - N96CS



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