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G/DAY JOHN

  I finally got around to putting the Stolspeed  VG'S on the MAGGIE and am very happy with the results.

The Jabiru 1600 gives about 50hp and makes for a relatively poor takeoff and climb performance. Now that I operate from the a new strip I was beginning to consider putting the VW back as I was usually only about 20ft above the fence at the end of the takeoff roll and the climb was 500ft/min. The climb could be lived with but I was worried that one day I would hit the fence.

'Maggie'  is a low-wing all metal of my own design.  Wing area is 92sgft.  MAUW 360 kg.  Wing Loading 8.6lb/sqft. Power Loading 16lb/hp.

Clean Stall 39knts and drops the right wing after pushing it hard enough.  Flapped Stall 33knts [centre section flaps and drooping ailerons]flaps drop 40 and ailerons 20 degrees with full aileron action]

The VG'S were fitted to the wing and elevator as per your instructions except that the centre section [ about 2 ft either side] had vg's at 60mm spacing because I used the wrong pattern.

After fitting the VGs, the test flight returned the following results:

Clean Stall  36 knts no wing drop and plane nods along dropping and raising the nose with relatively low descent rate

Flapped Stall  30 knts and similiar to above.

No noticeable change to cruising speed. The Maggie always had a relatively powerfull elevator but the feel at slow speeds and on approach is much improved.

The biggest improvement from my point of view is the takeoff ,the nosewheel lifts off at 27 knts followed by the plane at 35 knts straight into a climb as it accelerates to my 55 knt climb passing the fence with around 60/70 ft.  This was in nil wind conditions.  Climb also seems slightly better at 550 FT/MIN.

The Maggie was never intended to be a stol aircraft and is not one now. On approach at 45 knts there is still plenty of energy to flare and holdoff with practice a 40 knt [or lower] approach should be a safe option given that I feel more in control at these slow speeds.

 Don, Queensland Australia

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