Phase 1 Update
Hello,
I now have 11 hours on the airplane and I am more impressed with the Vans product than I expected. I am 5'11" and I have the rudder pedals in the middle location with the seat back in the most forward location and a 1" booster cushion under my Classic Aero seats. That position gives me very good visibility and my legs are quite comfortable. The aircraft is truly roomy. Stalls are basically benign both clean and full flaps. No wing drop just a little buffett and altitude loss. To recover simply reduce back pressure to break the stall then add power as needed to regain altitude. The landing flare is predictable and the gear are solid and consistent. It is surprisingly easy to land and stable during the rollout.
The controls are well harmonized without the pitch sensitivity I have experienced in many EAB aircraft. My first two flights concentrated on watching engine gauges and general control feel. I did need to adjust the propeller low pitch stop and the left aileron, but small changes like that are to be expected.
The third flight confirmed the adjustments previously made and I recorded the amp draw of each item I could turn on and off to verify my load shed ability since I have a totally electric aircraft including ignition and fuel injection.
Flights 4, 5, and 6 were used to calibrate the fuel flow and other engine sensors. Toobuilder previously posted a question on the SDSEFI fuel flow calculation. I do not have a flow meter in my system, I use the software inside the SDSEFI. For my IO-390 I turned the fuel pressure up to 49PSI from the factory standard 40PSI. This was done because to adjust air fuel ratio (AFR) at 100RPM increments you input a value between 0 and 255 at each increment which tells the injectors how long to stay open. At 40PSI I ran close to 255 at 2600 and 2700RPM. At 49PSI the numbers are lower and my average injector duty cycle is well below 60% (closer to 40% under most power settings). An obvious question would be why 49PSI and not a nice round 50? Well my Garmin sensor kit included a Kavlico P4055-50G sensor that is a 50PSI sensor and the numbers go blank at exactly 50PSI
. I need to see if there is such a thing as a Kavlico P4055-60G? In the Garmin G3X system, for the fuel flow measurements I chose "Fuelscan 201B" and for the return flow I chose "none". With those selections I needed to increase the K factor about 17.25%; old K = 29500 new K = 34587. The K factor can be adjusted in either the SDS computer or the Garmin system to the same result, I chose to adjust the Garmin. I may tweak the K value slightly, but currently I am very happy with the fuel used versus fuel pumped at fill up time. BTW, increasing the fuel pressure may have increased the need to adjust the K factor?
A quick side note, we are very fortunate in the EAB world to have access to systems like Garmin, Dynon, GRT, etc... I have features I simply could not afford in my previous certified aircraft. These are many of the same features I enjoy at work, but that aircraft cost more than a lifetime of income, okay 20 or 30 lifetimes
. Also the electronic ignition and fuel injection make starting my Lycoming as simple as pushing the start button. Imagine that, it starts as easily as my car which cost far less, no hot start or cold start procedures, just push the button
. It runs VERY smooth and I have not yet balanced the prop!
Flight 7 served no purpose because weather interrupted my plan. I was testing the SDS fuel trim option. One thing I noticed is the Vans baffle system for the RV-14 is very impressive. I trimmed the fuel (about 1 to 2%) to match the EGT's and noticed the CHT's were amazingly even with lots of room to spare for my planned future cowl flap system. All my past experience with Lycoming was to find peak either on the Alcor gauge or by finding the "rough" spot then increasing mixture for best power. I tried to simulate that experience to my great surprise. As I leaned, the engine remained exactly as smooth as before. The EGT, CHT, and IAS changed then suddenly dropped yet the engine never gave ANY hint of roughness. I think I just experienced Lean of Peak and it was anti-climatic
. I would have liked to continue learning, but weather intervened.
At this point, I am satisfied the engine sensors are good so my future flights will concentrate on calibration of the pitot-static system to see what speeds I can get. I really see no point in publishing speed numbers until I know they are accurate. Once I have accurate speed numbers I will move on to Vx, Vy, glide speed etc.. and I will work on my cowl flap system to see if it actually increases speed or merely CHT's.....