First Test Flights
First flight of new Aerolite 103 “BG” this afternoon 10/6/2022. (Sorry no video as used new camera mount and had technical issues with the cam-so here is the written narrative story for those interested.) Plane flew beautifully. No more “draggy” than my Cubcrafters Sport Cub with full (40 degrees) of full flaps. Only surprise was warnings about winds aloft are not exaggerated, I flew at 2PM with winds at surface only 4 mph, but once aloft if was very active rocking and rolling. Shoestring Airport is surrounded by hilly terrain and very tall trees, so I may have been experiencing turbulence as the downwind leg of pattern is parallel to a ridge with tall trees and the wind was flowing over this perpendicular to me. I was flying a very “tight” pattern so as to be able to reach airport if engine quit.
Ailerons alone were slow to level wings when hit with gusts that lifted my right wing. Rudder is very important on this plane. Jens Scott (Henry’s CFI Dad-Henry is teenager that flew his 103 from VA to Oshkosh) counseled me that rudder-aileron coordination was very important so I had no worries but rudder was even more important than I expected. Adverse yaw can fool with your head. Takeoff-lift off in 250 feet and accelerated to 50 mph for climb. Final approach—I decided to always wait to begin my descent and descend at a rate no less steep than if my engine quit/to insure I will always make the field— so nose down, cut power a bit to descend at about 10-12 feet per second at 45-50 mph per Mark Murray (pretty steep-about equal descent rate to engine out glide)-15 feet above runway pulled yoke back a bit to slow descent, at 2-3 feet added tiny amount of power, and just before touch down I pulled yoke back a tiny bit momentarily and pulled power to idle—touching down gently on two wheels with front wheel maybe 3 inches off ground—front wheel came down quickly. Completed landing roll out without brakes using only about 300-400 feet of the grass strip.
Rather than repeating the flight around the pattern, I thanked God for His help and reflected on everything I could remember and pulled plug to check mixture. The density altitude was nearly 1000 feet higher than my recent ground testing and engine felt like it was running rich. Plug check confirmed that so I guess the Tillotson carb is very sensitive to mixture settings. Engine rpm during full throttle climb was 5200 and ran strong but transition from 70% throttle to full was not optimal with a bit of ”four stroking” that ”spooked” me a little.
OK Here is my second flight. Resigned to fact I need to fly later than 1.5 hour before sunset, delayed supper and I took off late today in 4 mph crosswind and 10 mph winds aloft-not much gust. Still getting "feel" for the plane, so I was conservative in my climb and turn angles and flew a tight pattern close enough to land with engine out. Engine tuning and fuel mixture (H=1 +6/30; L=1+3/30) is "close" at 1400' Density Alt with good CHT and EGT--could possibly run a notch more ROP and maybe a bit more prop pitch to reduce EGT 50 degrees. On base turn, I reacted to an incorrectly calibrated inclinometer and it took my attention from descent rate as I corrected with right rudder trying to figure why the yaw string was stuck--leaving me high on final. Solution was steep descent with slip, arrested at about 10 feet AGL, and soft touchdown at a bit more speed than ideal. Leading with rudder is a good thing, but too much of a good thing is bad---reminder to me that the elevator makes the plane turn. Skids are very bad--and yaw strings can get tangled---I will remove the knot at the end. 
Here is a Youtube--hope it is helpful to some, interesting at least to others.
Here is video of 3rd and 4th test flights for ”BG” new Aerolite 103 in Pennsylvania on 10/28. (Long wait for ideal wind conditions.) Getting comfortable in the plane. I am climbing at shallow angle at 50+ mph (even still getting 600 fpm). Same 50+ mph with approach and touch down at 40+ mph. All to be conservative since plane is still new to me. Still at that still only using less than 500 feet of runway without brakes. Will now work on climbing out steeper at 40-45 mph--45 mph approach and touchdown at 30-35mph.
The thing most attracting my attention is turning away from and into wind (in other words when wind is impacting the upward aileron of the inside wing) The Aerolite requires a bit more aileron force than I am used to-leading with rudder helps but takes practice to avoid skidding. I think the Aerolite ailerons are a bit shorter in length than a lot of other planes I have flown. About half the length compared to the Challenger in the hangar next to me.
In my next test flights I will try some Dutch rolls and 15 degree turns about a point to build more skill on keeping aileron and rudder coordinated in the Aerolite.
Was about 45 degrees F today at altitude. I wore same gear as when riding my motorcycle-full face helmet, neck tube, heavy wind proof jacket and thick gloves-very comfy. I think I will be good as long as temps are above 38-40F
I adjusted the HS jet more rich from +6 to +7. Density altitude was around 300 ft.
I was disappointed that my radio and antenna that had superior performance with engine off was terrible with engine running. The antenna is picking up electromagnetic radio interference from the engine plugs, wires and CDI coils..big time, so need to make some changes. More research and experiments.
See my post on On Board Communications.
Nice weather day on 10/29. Conducted test flight no. 5 for “BG” Aerolite 103.
This time took off and flew entire flight with 5 degrees of flaps. I liked how plane handled. Plane showed be capable of more than 1000 feet per minute climb.
Density altitude about 500 ft. +7 HS jet setting showed some signs of being “rich” during taxi operations, but EGT was 1225 during 75% cruise.
Shortened yaw string/it performed well. Good redundancy with inclinometer. Avoiding skids with this plane requires vigilance as rudder is important to initiate and control turns.
Honing landing skill with timed yoke back with soft touch down on mains with nose wheel 3-4 inches high.
Happy that radio with new Faraday Shield Ground Plane mod reduced interference enough to make radio functional. After flight I modified helmet mic for better voice volume.
The more I fly this machine, the more I like it. Now at 5.6 engine hours.
Next flight will practice more maneuvers. Waiting for weather to cooperate. My weather "minimums" are now: Max surface wind 8 mph--maximum gusts 12; Max wind at 1000 feet 12 mph. Plane handles crosswinds well--but its does not like gusts. Reacting to wind in the Aerolite 103 requires a unique and sensitive combination of rudder and aileron.
One of the most important tasks of the first test flights is to verify the accuracy of the air speed indicator instruments. This was done using GPS metrics from the Garmin VIRB camera, compared to readouts of the UMA Air Speed Instrument and the Hall Air Speed Indicator, taking wind speed and direction into consideration. The UMS instrument is very accurate down to 20-25 mph. The Hall indicator reads 3-5 mph high at cruise, but seems accurate at speeds below 40 mph. In either case, I would trust either for 40-46 mph climb and descent speed as well as my personal minimum flying speed of 35 mph.
Angle of Attack is one of the most critical control choices of the pilot in order to avoid stalls. In a previous post, I address this in detail. Wing Pitch Angle = Angle of Climb + Angle of Attack. One method of "controlling" Angle of Attack is to provide a visual reference for Pitch Angle in the pilot's "sight picture". In the pic below, you can see that I added two horizontal "lines" on the windscreen that line up with the pilot's eye line of sight. The top line is "Level" meaning the plane "airframe" is level so the Wing Pitch Angle is equal to the wing's Angle of Incidence or 5 degrees. The lower line is "Climb" set when the Wing Pitch Angle is 11-12 degrees. During tests, with a climb rate of 360 FPM with an air speed of 55 mph, using the angle whose sin is 0.09 (around 5 degrees) it can be determined that the corresponding Angle of Attack at 12 degrees of Wing Pitch Angle is 7 degrees. AOA=7 degrees.
Since we are at max power, increasing the Wing Pitch Angle will reduce air speed and will increase Angle of Climb. Estimating that 46 mph with 900 FPM climb (13 degrees) would require a Wing Pitch Angle of 21 degrees. Angle of Attack would increase to 8 degrees.
So the 11-12 degree of Wing Pitch Angle indication line in the pilot's sight picture would be a safe the minimum nose up attitude for a climb. Holding the line about an inch or two above the line to increase climb to 600 FPM would be optimum.
Now, assume that speed dropped to 35 mph, while still climbing at 900 FPM. That is a 17 degree Angle of Climb. Because of substantially increased drag, it is probable that Angle of Attack would have to be increased to 13 degrees, requiring a Wing Pitch Angle of 30 degrees. (A power on stall would confirm this as Stall AOA is estimated to be 15 degrees (begin) and 17 degrees with complete loss of lift.
So in a full throttle climb, avoid Wing Pitch Angles above 20 degrees.
Here is a pic below showing the attitude of the plane during climb, using the tail and nose wheels as reference. The 11-12 degree Wing Pitch Angle mark of "Min Climb" produces a low 360-400 FPM rate of climb. (It is about the same attitude as the plane on the ground with the nose wheel about 5-6 inches off the ground.) The 15 degree "Prudent Climb" would produce 600 FPM at 52 mph with excellent engine cooling. A steeper pitch would allow a higher rate of climb but with a significant increase in CHT and engine stress so such higher rates should be for short periods of time to avoid obstacles. Keep in mind that slower speeds reduce air flow over engine, AND a higher nose up blocks some air flow to the engine that is mounted behind the wing.
In a descent, Wing Pitch Angle = Angle of Climb + Angle of Attack. At a gradual rate of descent of 300 FPM, the descent angle is a negative 5 degrees--Since the "Level" mark on the windscreen is 5 degrees of Wing Pitch, the Angle of Attack would be 10 degrees while holding this pitch. At 600 FPM descent at 46 mph would be about a negative 9 degrees Angle of Climb. To keep the Angle of Attack at a safe 8 degrees, the Wing Pitch Angle would need to be 1 degree down. Since the "Level" mark on the windscreen is 5 degrees of Wing Pitch, the line would have to be BELOW the horizon by about the same distance as the spacing between the two lines or about 6 degrees. Any faster descent rate would probably be best achieved by increasing air speed. e.g. a 900 FPM descent at 55 mph would be a negative 10.5 degrees Angle of Climb, and with a negative 1 degree Wing Pitch, the AOA would be 9.5 degrees. An approach with a nose up attitude would be possible, but only with a very shallow descent rate angle.
In a descent, be sure to put the "Level" line below the horizon--the faster the descent, the more below. You can stall when descending. (A steep descent of 1800 fpm and 65 mph would initiate a stall—and pulling out of such a steep dive at higher speed would be very dangerous with possibility of exceeding the g limits of the wing structure.)
At approach (in ground effect no more than 15 ft. AGL) and touchdown, raising the nose up should be at the same proportion as the reduction in descent rate. So if Angle of Climb should be reduced from 600 FPM to 90 FPM (1.5 FPS) the "LEVEL" line would need to be slightly above the horizon--more just before touchdown. The "LEVEL" line is a pitch where the nose and mains would touch at the same time--if the line is above the horizon, then the mains will touch first. This method will force the pilot to view the end of the runway/horizon and not the ground rush. Pulling the nose up too early or too much may result in the plane slowing down to stall speed before it touches down resulting in a very hard landing.
Similar references in the video’s except because the cam is lower than pilot’s eye, the “Level” line reference for the video is the top of the dash.
Keep in mind that all of the above AOA info is based on flying with no flaps. Wing Pitch Angle is the sum of "Pilot Observed Airframe Pitch Angle" + Angle of Incidence. Adding flaps essentially increases the Angle of Incidence and to an extent changes the wing's coefficient of lift. With flaps deployed, there will need to be a reduction in "Pilot Observed Pitch Angle"=less nose up in climb and more nose down in descent.
Here above is the 6th test flight for BG. Not my best flying, but that is the objective of these “test” flights: To become familiar and comfortable with the plane and its characteristics in different maneuvers and flight. First time on Runway 15.
The approach is different in that buildings are very close on the right side and there is a steep bank on the left. As you descend, high trees can create turbulence. I fly a round corner pattern to avoid flying directly over homes. I am keeping my turns relatively shallow, and my speeds relatively high to be conservative. So my landing was subpar, but safe.
I was able to do a well coordinated 360 degree 15 degree banked turn, but did not display sufficient coordination of the throttle and elevator to hold altitude within a 50 foot range.
My Dutch Rolls were OK, but confirmed my tendency to apply rudder too aggressively to initiate turns. (I was taught on most general aviation planes to input rudder and aileron simultaneously. The Aerolite seems to fly better if you lead with the rudder just milliseconds ahead of the aileron. ) I need to be more gentle with rudder and control more gradually, and couple aileron input with less delay, especially when I am keeping bank angle in the 15 degree range—the rudder is very sensitive and powerful--a slight movement produces immediate and larger than expected results. I am eliminating adverse yaw with my rudder input timing, but I am introducing a slight skidding attitude. (I am also probably holding rudder input a bit too long while turning. Always reminding myself that aileron and rudder initiate bank, but elevator primarily maintains the plane’s turn.) Not a problem while I am flying with excess speed and shallow turns, but a bad “habit” when I start pushing the plane to higher performance levels.
Some will certainly conclude I am overthinking this, but developing precision and extreme proficiency is key to being able to graduate to more complicated and critical maneuvers—steeper turns, higher climb rates, and slower speeds.
The ”tests” have so far given me a pretty good understanding of what control inputs the plane needs..and what I need to do to improve in regards to my inputs.
Examining the landing in this video, you will see I misjudged my alignment during landing approach because I was subconsciously avoiding the buildings close on the right, as well as misjudging the extent of the banking on the left and had to make last second adjustments close to the ground. This distracted me during the ground effect roundout phase that requires perfect timing. Just points out how important a stable approach with no surprises is to good landings.
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