Here is a list of some problems and corrective actions during the first 75 hours of flight time (first flight 22 July 2000). This is a slider RV-6A with gyro panel, RMI Monitor, GX-60 GPS/Com and NavAid AP-1. Powered by 160 HP O-320 with Paul Irlbeck wood prop.
Heavy left wing. - I tried to correct it by bending the aileron trailing edge but this wasn't enough so a tab was added under the aileron. Latter I removed the tab and made the adjustable electric tab slightly larger. Next, I found that the full up flap position needed correcting on left wing. I corrected this and removed the added trim augmentation. The inner aileron hinge had to be moved to align with new flap position.
Brakes - I had some trouble filling the system (from the calipers) until a learned it was necessary to pull pack on the tops of the pedals. My master cylinder springs were not strong enough to fully retract the pedals. I got the brakes hot during taxi testing to condition the pads. One day after about the 3rd flight the right brake lost fluid as I set them prior to engine start. The Caliper O ring had failed because of excess heat. The brakes were dragging. I built some spacer to fit under the master cylinder springs and have not had problems since.
Leaking fuel tank inspection covers - I sealed my tank covers with the cork gaskets covered with fuel lube and tested the tanks with air pressure prior to using. Before installing the tanks I replaced the Phillips screws with hex head machine screws. I had some leaks around the access covers and after several rounds of tightening these screws (now accessible without removing the tanks), I have stopped the seepage. At first I was reluctant to tighten too much because I didn't want to damage the gasket.
Tire Wear - The outside treads of the main gear tires are warring. I reversed the left tire at 50 hours and will reverse the right tire soon. I may get only 150 hours out of these tires.
Sealing Cockpit - As the temperature started to cool here in Minnesota, I decided it was time to start sealing the cockpit. I added boots to both the aileron and flap control rods where they exit the fuse. I also sealed the corrugated areas of the rear bulkhead to prevent air from entering from the tail cone. I still get some cool air on the back of the head and plan to put some weather stripping under the rear skirts.
NavAid - Although the AP-1 does an excellent job of tracking when coupled to the GX-60, there was some stick shaking especially when there wasn't much loading on the ailerons (Tracking is much enhanced if the CDI resolution is set to 0.3 NM in the GX-60). NavAid said this is common in RV's with light control forces and offered to modify the servo with a resistor if I sent it in. They sent me the 5 ohm 3 watt resistor, which I added inside the servo in series with the motor. This solved the shaking problem and now the unit works great at all air speeds.
Prop Balance - With limited experience with in a RV I didn't know what kind of vibrations to expect but did notice that when I throttled back to 1500 RPM vibration was noticeable. At 70 hours I had the prop dynamically balanced by Doug Shears at Harmony Aviation. The pre-balance reading was 0.57 IPS and after balance it is 0.025 IPS. Doug said the prebalance conditions were bad but not severe. The aircraft is much smoother now at all RPM. This was well worth the expense. Doug has balanced about 3000 props and travels within a 10 state area around Minnesota. Get several airplane together as he gives discounts for groups.(Doug Shears @ 800-SPIN BAlance)
GX-60 software –After getting some really dark sun glasses, I found it difficult to see the GX-60 screen. I visited the II Morrow people at Oshkosh about this problem and the fact that I couldn't set the units to MPH. They said all these issues were addressed in Software Release 3.2. I ask for the update since the unit was still under warranty. They don't provide software updates under warranty. I would have to buy it. Some shops wanted $150, but I found a shop that supplied it a no charge even though I bought the unit by mail order. The update was a disappointment; the MPH only changed one nav screen while the map display stayed in knots. The adjustable brightness allowed manual settings to override the photocell light sense, it didn't increase the brightness. An additional "enhancement" that starts a turn prior to passing a waypoint only generates a curve on the screen prior to waypoint arrival but doesn't change the CDI until the waypoint is reached. I am happy with the unit but there is room for improvement.
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