Real plane stuff usually doesn't translate well to models, however, for me modelling is for imagination and experimentation. With that I wanted to see how Vortex Generators VG's would translate to model airplanes. My experience on my personal experimental plane has changed the flight characteristics from a handful to delightful. Lowering stall speed, more effective control response at low speed, shortening takeoff and landing respectfully, and of course a slower cruise. The saying goes Lift is Drag and VG's provide lift and the also create drag. So, with that I decided to take my Flightline OV-10 and install some VG's on the wing and see what happens.
OV-10 VG test complete! Speeds obtained done with Spektrum onboard GPS. Weather: 10miles, 12000ovc, winds light 2-4 out of the east. Takeoff runway 36 and was slightly shorter than normal by about 3-5 feet. Initial response was a climb like I haven’t seen plane do before. Gear up flaps up and did normal cruise power of 70% throttle. 45mph into the wind 50mph with the wind, a loss of speed it appears. Pushed it up to full power and 55mph into the wind 60mph with the wind. Normal speed without VG’s full power is 70mph plus average. Stalls: I did three stalls and the plane got pretty slow. Stalls were done into the wind power off and each stall presented a 15-18mph GPS Groundspeed. I did a few stalls the other without VG's and they averaged 18-20mph. The stalls also did as GliderGuy and I predicted, mushed and no fall off on either wing unlike the other day. Adding 20-25% throttle immediately arrested the stall to recovery. Landing was crosswind and a little shorter than normal with a much higher alpha presentation on Flare. All said they did as I predicted though I need more up elevator authority. Will I keep them on? Up for debate though I will do a few more flights with them on to obtain more data.
An interesting experiment that I wanted to share.
Richard
OV-10 VG test complete! Speeds obtained done with Spektrum onboard GPS. Weather: 10miles, 12000ovc, winds light 2-4 out of the east. Takeoff runway 36 and was slightly shorter than normal by about 3-5 feet. Initial response was a climb like I haven’t seen plane do before. Gear up flaps up and did normal cruise power of 70% throttle. 45mph into the wind 50mph with the wind, a loss of speed it appears. Pushed it up to full power and 55mph into the wind 60mph with the wind. Normal speed without VG’s full power is 70mph plus average. Stalls: I did three stalls and the plane got pretty slow. Stalls were done into the wind power off and each stall presented a 15-18mph GPS Groundspeed. I did a few stalls the other without VG's and they averaged 18-20mph. The stalls also did as GliderGuy and I predicted, mushed and no fall off on either wing unlike the other day. Adding 20-25% throttle immediately arrested the stall to recovery. Landing was crosswind and a little shorter than normal with a much higher alpha presentation on Flare. All said they did as I predicted though I need more up elevator authority. Will I keep them on? Up for debate though I will do a few more flights with them on to obtain more data.
An interesting experiment that I wanted to share.
Richard
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