From Matronics
Heads Up Display Mounting Bracket for AOA Sport
When it was time to find a suitable location for the AOA Sport (Advanced Flight Systems) panel mount display in my RV9-A I wanted it to be in view during approach and landing.
Outside looking in at bracket
My first thought was to mount it near the airspeed indicator, but I remembered a note I had read about reflecting the led display off the inside of the windscreen. (
EM Aviation) Not being sure if it would actually work I designed and built a mounting bracket for the display that could either be mounted for direct viewing or laid flat to reflect the display off of the windscreen.
The bracket is little more than a short piece of 1/2" aluminum channel and a few pieces a aluminum angle painted flat black. A short bolt with a locknut allows the display to be raised or lowered. The bracket itself is attached to glare shield with a couple of strips of double sided foam mounting tape.
Fold ribbon cable through grommet in glare shield
The wiring for the display is routed through a grommet in the glare shield. The AOA display must be installed in the bracket so that the green leds are forward and the red leds are aft. This produces a reflection with the green leds at the bottom and the red leds on top.
Finding the correct location and angle for the display took some trial and error. The bracket needs to be as far forward as possible to create the brightest reflection of the leds. Because of the compound curvature of the windscreen it works best to place the display in test mode (press Red Button) and move the mount until the reflected display is in your desired line of sight and the leds are vertical when seen from your normal viewing position.
Silver reflective film above display
After a few hours flying I found that the leds were visible in all lighting conditions except direct head-on sunlight. To correct this I placed a small 2"x3" rectangle of silver window film on the windscreen above the display. The display is now visible in all lighting conditions. I think the size of the film could be reduced and could be as small as 1"x2" if you place it in exactly the right spot. An unexpected side effect of the film was the elimination of the double image that was present before the film was added.
I have not yet flown at night with this display, but the AOA Sport has a very effective dimmer control (Black Button) that should cut down on the distraction the lights might cause.
Having the display in view during approach and landing is very helpful in adjusting approach speeds. Once the AOA is calibrated there is little if any need to refer to the airspeed indicator to maintain the best (and lowest) landing speeds.
