Walter Klatt

I guess it all depends on the wing. I looked the Jab site, and see that the 160 has a pretty small wing compared to the Rebel. Interesting too, that you actually gain some speed with slight flap. The Rebel is the opposite. It gains speed with reflex. Well, that's the nice thing with these VGs. With that double sided carpet tape, you test it first, not only for location on the wing, but if you don't like the performance, pull them off. My other plane (912 Chinook) didn't benefit much from the VGs, only about 2 kt stall reduction, but again no change in cruise speeds. The only reason I wanted the VGs on the Rebel, was to improve water take-offs, and they do that, so am happy. Otherwise wouldn't bother. Stall speed was good enough before, for my type of flying. When on floats, you really can't utilize a low stall speed on landing, because the angle of attack is too severe (would drag the float tails). Walter

VGs and cruise speed This is very interestesting and is the first time I have heard of a significant change in speeds with using VGs. While I am not familiar with the J160 cruise speed or wing airfoil (am in Canada), I have used VGs in two of my airplanes and found no detectable difference in cruise speeds. Can you give us more info on exactly how you measured your cruise speeds and corresponding power settings? One of my planes is a Murphy Rebel amphib which cruises at 120 mph and I did extensive tests with and without the VGs to determine the difference. While my stall was reduced by 5+ knots, I could not detect any difference in cruise speeds. I used fuel flow (have a fuel flow monitor) and RPM at the same airspeed (and weight) for my tests. I know this is very accurate for my airplane as fuel flow will change immediately with any changes in weight or flaperon settings. For example, there is a .5 gph reduction in fuel flow from neutral to the reflex flaperon position to maintain the same airspeed. Conversely, to maintain the same fuel flow, there is a 5 knot difference in airspeeds between the neutral and reflex positions. So any drag or cruise speed differences in my airplane are easily detectable. But I could not find any such differences with the VGs on or off. Maybe it has to do with the airfoils. The Rebel has a modified 4415 with a 30 ft span. I do not use the VGs on the tail, just the wings. Walter

Yes, I tried them first with the double sided thin carpet tape, and then glued them on with Loctite 401. Walter

Landshorter VGs I use the Landshorter VGs on 2 of my airplanes. One is a Murphy Rebel amphib floatplane, and it has them at the 10 % chord position. Results were much better than expected. Stall was reduced by about 8 or 9 mph. This was at the recommended 10% chord position. Then I put them on my 912 Chinook, also an amphib floatplane, and for some reason, did not get anywhere near the same results. First, I tried them at the 10% chord position, but stall only reduced by about 1 or 2 mph at best. Then Joa told me to try them further forward, and that helped a little. I ended up at the 7 % chord position, but still only about 2 or 3 mph stall improvement. So it seems to depend a lot on the wing airfoil, I think. The Rebel has a modified 4415 wing, and not sure what the Chinook has, but it is thinner, and it is also a fabric wing vs the metal for the Rebel. No change in cruise speeds or any other handling or stalls with either plane using the VGs. Water take-offs on the Rebel are now faster, but they do require more power and/or technique change, as the VGs produce more drag at low airspeed and a higher angle of attack. I think climb is better, but that is hard to prove. Walter

I recently intalled a new A210 in my airplane. It has the new firmware upgrade that fixes this problem. It is version 1.23.001. You can check your firmware by holding the Frequency Exchange button while turning on the unit. If the new DW feature is activated you will see an additional menu item called Priority Watch just below the DW Interval item. To activate this feature in your A210 you need set your Mem Clear item to ALL and press and hold the Mem button for 2 seconds. This reinitializes the CPU and activates the Priority Watch feature in the Menu Selection. If you don't have the correct firmware, you can send your A210 to the nearest Icom service centre and they will update it for you for free. I like the radio so far, VOX works well, and they tell me my transmission is very clear and understandable. Walter