Contacted Dennis Carley at Aerolite 103 in June and was told wait list of 12-14 months. I asked about the “show unit” from Sun and Fun and he mentioned that plane would be for sale after Oshkosh first of August, equipped with a MZ201 engine and three blade IVO prop. (From pic at Sun & Fun, it appears it showed there with one cylinder engine and wooden prop.)
On June 25, I sent my check for $32,120; full price payment in advance. (No “show” or “demo” discount!) I also sent a check for a special instrument panel to accept additional UMA ASI and ALT gauges I intended to install.
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| Custom UMA Air Speed Indicator with V color coded |
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| Standard Panel |
On July 1, I sent $1,000 deposit to DeLand Barnstomers for transport from Deland, Fl to Stewartstown, PA. ($2500 total)
On August 5, plane was ready for shipment, but DeLand Barnstormers called indicating his trailer had mechanical failure and he was not sure when he could pick up my plane. One week later he called and said his trailer was repaired and he was going to pick up the plane on Sunday, August 14. He was not going to leave until Wednesday as he had other commitments.
Because of the uncertainty of Deland’s plans, I had investigated driving to DeLand FL in a one way rental car and picking up the plane in a 26 foot U-Haul. Cost would have been less than $2000; less than the $2500 DeLand charged.
Finally, DeLand Barnstormers departed on Friday, August 19. The following day his trailer suffered a 2nd spindle failure and he did not arrive until 6PM on Sunday, August 21.
DeLand’s rig is huge. Too tall and long to navigate the entrance to Shoestring Airport. He had complained about “not making any money” on a hotshot delivery of one plane, so he arrived with my plane, another Aerolite for delivery in Indiana, a racing motorcycle. In order to reload the motorcycle he needed a flat area, so instead of unloading at the airport driveway, he moved up hill 1/10th mile—now 1/4 mile from my hangar. It took my crew of four over two hours to move everything into the hangar.
All in all, DeLand Barnstormers was polite, careful and competent. Plane arrived in good condition. I did not care for the uncertainty as to arrival. Also, he essentially unloaded the plane and parts just past the end of his trailer ramp and really did not help moving everything into the hangar. (I figured he did not want to leave his rig unattended with his Great Dane dog companion inside.) He did request that I provide assistance in reloading his racing motorcycle, which I did. (Like the pic below) His trailer did not have a winch that could be used to move the heavy motorcycle up the ramp to the back of the trailer.
While waiting I constructed racks to store the wings and tail while moving them and holding them in hangar for installation. I also fabricated an adjustable height stand to support wings during install. I also used existing adjustable wing supports available to all hangar occupants.
On Monday, August 22, I began the process of putting the wings on and discovered that four “saddles” for the wing struts were missing. No answer at Aerolite so I contacted their dealer Mark Murray who sent the parts USPS two day. Dennis Carley returned my call that evening and overnighted parts UPS. Parts arrived late Wednesday PM. Wings installed 8/25.
On Friday, 8/26, started installing tail and found that incorrect saddles for horizontal elevator were shipped. Correct parts arrived Tuesday 8/29. Tail installed 8/30. Dennis Carley was very prompt and responsive to my questions and issues. In defense of Aerolite 103, Carley did offer to test fly the plane before shipment but I declined as I wanted to break in the engine myself—the parts “mistakes” probably would have been corrected if they had assembled the plane after returning from Oshkosh. (The wing fabric was damaged while in the trailer coming home from Oshkosh and was replaced with new before shipment to me.)
I only had one issue with the manual. It is not as comprehensive as the one for kits and the instruction regarding the attachment of the down wires for the horizontal stabilizer was incomplete.
Not terrible having an assembled plane in my hangar about 2 weeks later than expected, but it was frustrating that the date of delivery by the transporter was so uncertain and then losing five days because of missing parts. (Sort of like Santa Clause coming two weeks late!) Still lots to do.
Next, the 62” Three Blade Ground Adjustable propeller came in a box unassembled. I was told to start with a pitch of 10.5 degrees, but instructions from IVO do not mention pitch angle at “neutral” rather, a call to IVO confirmed “neutral” is 35 inch pet revolution. That is where I set it for initial running. Torque to 200 inch pounds.
pitch by bending blade for clockwise pusher prop. Neutral is 35 inches per revolution. One full turn of the adjusting screw will change rpm by 200 -300 or about 3” per revolution. Adjustment is limited to + or - 5.5 turns from neutral from 18 to 52” or 3 to 17 degrees pitch.
Certainly 62” is max propeller diameter. Note the horizontal blade clearance.
Before weighing the plane, I decided to remove the nose wheel pant. I was thinking of best way to take hold of plane while moving it in and out of hangar. I decided the nose wheel yoke was a good “handle” but I was concerned that the 0.060” thrust spacer was inadequate, so I fabricated a stronger one and added two thrust washers. The spring appears to be 300# per inch, so with normal operation, less than 1/2” deflection is expected during landing. Deflection with pilot seated will be less than 1/8”.
Next I sat in the seat and found my head hit the overhead control switches: master, engine info, magnetos, flaps, and starter. I relocated all of the switches upward so they are above the main beam. Hard job with wings installed. Tested wearing my helmet I can move around OK..my helmet can bump into the overhead beam, but no chance that a switch will be turned off accidentally during flight. I will attach wing fabric buckles to overhead beam with Velcro and pad the areas where helmet impact is possible.
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| After with 1/2 “ above edge of beam |
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| Full face “modular” motorcycle helmet |
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| Comtronics with Aviation Headset |
Not happy with lumbar support in the seat. Taking off the vinyl seat cover and soft foam, replace bottom cushioning with high energy absorbent padding and full 2.5-3” lumbar support. The cushion is only 1/2” thick to preserve headroom, but my calculation indicates it can absorb 8g force. I will also add anti-submarine crouch belts. Having experienced several auto racing impacts, I am very picky about seat ergonomics and protection for head and spine.
Cervical and thoracic vertebrae compression injuries are much more probable with a vertical or horizontal impact when sitting in a flat back seat without proper lumbar support, especially if pilot projects head forward to avoid hitting head on overhead structure.
The submarine straps were made from “soft ties” modified to get correct reach. They provide restraint to the thighs and are tightened up when the shoulder straps are tightened.
Their is clearance for helmet but not much. Still, with hard surfaces close to the head in rough air a helmet is mandatory.
Finally, plane is ready to leave the hangar, break in the new engine and do some ground taxiing. Engine started easily and ran well. First day about 15 minutes running. Second day about 30 minutes of running and much faster taxing/reaching 25 mph and very brief 4500 rpm spurts climbing the small grade between runway and taxiway. Reached 325F CHT and 900 EGT. Next I will tie plane down and run full throttle static test. I expect 5200 rpm with 35” (10 degree) pitch.
Seat and ergonomics worked great for both helmets! Rudder pedals and ailerons worked well—able to hold a very precise centerline with an 8 mph cross wind.
Received the custom ASI and ALT from UMA mentioned earlier on 9/9, but Aerolite still has not shipped the new panel. They said powder coating was holding things up, but when I asked them to ship it without the coating, it was not shipped—apparently not made yet.
I like the Hall airspeed instrument, but did not intend to fly the plane without the precision UMA ASI and although the EIS shows altitude, again I wanted the precision UMA gauge installed.
So, resigned myself to having to modify existing panel or make a new one myself. Fortunately, Ricardo Trujillo, the electronic guru at airport had a 2 1/4 in manual punch die set so I figured I could do the job, even though I would have liked to have had a shear. Careful use of a jigsaw and some filing will do. May add an overlay to existing panel for strength or just make a whole new panel.
Another possible complication. Checking out what I needed to do to remove the panel, Ricardo noticed that the EIS box was dented and a stand-off broken off, sitting inside but stuck to a piece of clear tape. See pic
Not sure where the stand-off came from, and concerned that it was the attachment point for the wire plug, decided to remove the EIS and inspect.
I also need to fabricate the mounting system for the ASI’s 1/4 inch dia. pitot tube. I decided that rather than having it stick out from the nose, exposed to damage while parked, I would mount it below the nose. Since the nose cone tapers up, by mounting the pitot tube level projecting from the rear nose shroud, it would be 6” below the nose without projecting out past. This would put it outside the boundary layer.
Accurate indication of speed and altitude are especially critical for safe flight in an ultralight, so I will need to complete the install before my first flight. (Many would argue that the Hall speed and EIS altitude are “sufficient” but as I have said, I am “fussy” when it comes to safety.)
I contacted GRT who provided valuable advice and analysis of the broken stand-off. Seems the circuit board is held in place by four screws, two of which are a stand-off/screw combo that provide female threads for two screws to secure the metal cover. The male threaded “stud” is a bit fragile and it appeared assembler at Aerolite pried on the unit or dropped it placing a lateral stress on the cover and the stand-off. To rehabilitate, I fabricated an alternative “stand-off/stud using a 1in long 4-40 screw, with 4 nuts and a washer locked to threads inside the cover, with a fifth nut to engage the cover outside.
I fabricated the overlay for the panel to accept the ASI and ALT out of 0.025” aluminum—two thicknesses added the 0.060 existing panel will give plenty of stiffness. Easier to cut the panel out of thinner material with shears.
I contoured the lower part to provide clearance for feet operating the rudder. The manual 2 1/4 punch worked well—took lots of torque to tighten the clamping bolt and a bit of filing/Dremel to get enough clearance for gauge face and to get an exact alignment of all three aluminum panels. The overlay provides strength in the area where the gauge cutout came within 1/4” of an edge.
Here it is, ready to install with Tiny Tach below the inclinometer.
Spent half the day installing the dash. Without the windscreen, it would be easy. With the windscreen most of the nylon ties need to be engaged with one hand, same for wiring and securing everything. EIS seems to work OK.
Spent the rest of the day figuring out where to mount the pitot tube for the ASI and installing it. Instead of mounting in the nose, I mounted it to the jury strut, well insulated from chafing, ran the tube inside strut fairing. Secured the tubing with nylon ties and Velcro.
The jury strut has an angle of incidence up about 10 degrees. Mounted the pitot tube level.
I tested the Hall device and the new pitot tube with a leaf blower, both reading close to same 30-50 mph readings. The relative accuracy was again confirmed after some fast taxiing.
After making adjustments to the throttle stop (set to maximum throttle position of the carb) and some initial lower RPM engine break-in operation (mostly doing taxiing limiting RPM to 4500 at 75% throttle) I readied the plane for a Static Run In with the plane tied down.
Aerolite shared some info regarding what they called "engine losing RPM" at near full or full throttle. They claimed or inferred that the Tillotson carb impulse drive fuel pump "ran out of capacity". This puzzled me a bit, but sure enough, at about 5100-5200 RPM, the engine did in fact "stumble" almost like it had a RPM Limiting Governor. I was able to reach 5450 RPM with a very gradual application of throttle.
In my opinion, the "limiting stumble" at or near max RPM is not due to the fuel pump but rather by the unique "dual venturi" design the the Tillotson HR carb. The high speed jet is controlled by a small secondary venturi. Below 75% throttle, air and fuel from this venturi flows smoothly on both sides of the throttle plate and joins the air and fuel from the low speed jet. Somewhere in the 80-85% throttle position, the throttle plate splits the air and fuel from the secondary venturi with an "angle of attack" that induces a "stall", creating a momentary turbulence. The max RPM of well designed gasoline engines is controlled by the size of the carburetor. At some point, air flow is limited at wide open throttle--even with no load. In my case, the max RPM of the engine with the 35" pitch propeller is 5450. And, to some extent may experience a "stumble" if throttle is moved from 75% to max too rapidly. For this reason, after the static run in, I readjusted the throttle stop to around 90% of max throttle plate movement and mounted a pliable material to cushion the stop. The plane will fly very well if I limit RPM to 5000-5100.
Yikes! During the run in I discovered a fuel leak at the fitting from the fuel tank to the "sight glass" system. More disturbing was that the clear "Saint Gobain C-210-A" clear polyurethane tubing crumbled like it was 10 years old. Not just at the fitting but at every location where it was compressed to mount it to the frame. C-210-A is claimed to be tolerant to fuel. The plane has a different brand of the same type, but tinted blue instead of clear, for the entire fuel supply to the carb. The tinted blue tubing appeared to be OK.
I removed the sight glass tubing and plugged the fitting from the tank. I also ordered an old fashioned fuel cap with a mechanical float controlled gauge to see if that would be satisfactory. In addition, I researched the possibility of replacing the poly tubing with race car quality steel braided, teflon PFTE lined fuel lines. Rule of thumb is that the clear poly tubing should be replaced every two years--it deteriorates over time from UV sunlight and high humidity exposure. There is no real need for "see thru" fuel lines. Some like to see the fuel move up when squeezing the primer bulb, but in reality, the best use of the primer bulb is to simply lightly squeeze until it is firm.
When the new fuel cap arrived, it fit except that the tabs needed to be bent .040” to allow for the thick 1/4” thick bung. In addition, the vent hole was only 0.060" so I added an additional 0.060" hole which should be more than adequate for the fuel flow on this engine.
Above pic is the fuel system without the sight glass using the clear blue polyurethane all the way to carb.
The new fuel cap gauge will read empty when there is still 1/2 gallon or about 10 minutes (4-5 miles) of fuel remaining. The gauge reading slightly above empty is with one gallon of fuel. (Because the gauge is a little more than one inch shorter than tank diameter, essential the gauge is reading the top 4 gallons. So when gauge reads 1/4, there should be two gallons left or at least one half hour or 20 miles of flight available.
To see the gauge, Pilot could loosen the left shoulder harness and turn head and body to see directly, or as seen thru the mirror, the pilot can glance at the rear view mirror mounted on the bar.
This eliminates the need for the several feet of clear tubing wire tied to the frame for a sight tube and reduces one source of fuel leakage.
I analyzed the venting for this cap, and determined it to be smaller than the cap that came with the plane. The gauge cap had only a 0.060" vent hole. I enlarged this to 0.080" and added a 0.125: hole in the center. i calculated this to be more than sufficient for 5-6 GPH fuel consumption. I became concerned about water intrusion and suction from air moving over the domed shape of the cap, so I fabricated a "ram air" cap cover and attached it with adhesive.
During the static run-in, I noticed that the CHT tended to be higher than I thought it should be. It rose faster than expected. I readjusted the high speed and low speed mixture setting about 10 degrees more rich and tested with more taxiing. I believe I am now running just a few points richer than ROP EGT which has lowered CHT's some and is where it should be. (This conclusion turned out to be very wrong-adjusting carb more rich fouled the plugs big time—the high CHT during static running was simply due to lower air flow over the engine.)
Cross winds and gusts have been high, so crow hopping opportunity has been limited. I have set a personal limit for maximum of a 5 mph crosswind gust component to insure that I am not distracted while the plane is off the ground during these crow hopping tests. (5 mph crosswind component is equivalent to 10 mph at 30 degrees) As the “test pilot” I want to evaluate the elevator sensitivity in ground effect.
Have now burned thru 4 gallons of Sunoco 260GTX (93/103=98 octane) There are 1.6 hours on the engine. I am mixing 3 oz of oil per gallon for a 42:1 mix. Slight dry carbon on muffler but no smoke. Oil seems to mix with green gasoline well. 260GTX is unleaded with no ethanol or oxegenates.
I found a good wind day and was able to perform five very nice take off and landings—i.e. crow hopping. But, most days the crosswind was too high.
While waiting for good conditions, I mounted my Virb Ultra 30 camera on the yoke so that I can analyze my inputs and the plane's performance during testing.
I decided to try my crow hopping after 6PM. On my first try, the engine would not run more than 3500 RPM—sputtering. Pulled plugs-they were soaked in raw fuel—way too rich mixture, made worse by low barometric pressure and a rise in density altitude. Changed plugs/ran better, two crow hops but still stuttering or what I would later learn the Aussies call “four stroking”-not firing on every stroke.
The next day I pulled plugs and they looked OK, but a tad too rich. Leaned to 1 1/8 turn on high speed jet and 1 1/4 turn on idle/intermediate. Ran two crow hops with excellent results. Pulled one plug-still a bit rich for 2500 ft density altitude, but probably just right for cooler days.
I decided that the mixture setting for the Tillotson HR197A carb was so sensitive that I needed a precision tool for adjustments.
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| After first more lean adjustment |
General thought by many is the color or darkness of electrode indicates rich/lean mixture. Darker is richer; lighter is leaner. The insulator in the final pic is lighter, but still some signs of unburned oil and fuel.
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| Decent plug condition after last adjustment |
The video shows a good takeoff blast-engine ran beautifully.
But, the next day, however was cold and high pressure, so density altitude was 750 feet vs 2000+ in previous runs. The engine cut out during takeoff acceleration--then able to be re- started immediately. Intuition indicated perhaps a richer mixture, but that did not solve the problem.
So, I researched the issue of propeller pitch and concluded that the suggested 10.5 degrees was not the same measurement referred to in IVO Propeller's instructions. (And that my mixture issues was related to the prop pitch being too low allowing the engine to be governed by air starvation rather than prop loading.) The 10.5 suggestion was measured at the tip. The IVO figure was the "geometric" pitch angle, usually measured at 75% of the tip diameter or 23.25" from the center of hub. I couple of iterations ended with a substantial increase in pitch with the engine still exceeding 5100 rpm during the takeoff roll. Final setting was 2.5 turns out from IVO's "neutral" measuring at 23.25" was 13.8 degrees. (Using the formula: Prop Circumference/Cotangent pitch in degrees=geometric pitch in inches) Calculated this is 47 inches. Using IVO's information, for 2.5 turns x 3.10 per turn, you get 43 inches.
The difference is most likely due to the change in propeller blade shape when adjusting pitch using IVO's design. The "average" pitch is no longer calculated at 75%, but closer to the tip. So we will use the 43 inch figure as it better matches what we saw on the engine tach. This is equivalent to a "geometric" pitch of 43 inches and 12.5 degrees.
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| 102.2-88.4 = 13.8 at 23.25" |
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| 100-88.4 = 11.6 at tip |
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| 1 7/16 " + 2.5 turns on 1x12 threads= 1.60" |
With 43 inch pitch and 35% slip, full throttle of 4700 RPM max hp should result in 48 mph climb and 70 mph top speed with 5% slip. (Flight tests indicate 5200 RPM 50 mph climb and 4700 RPM--75% throttle cruise at 55 mph. This indicates that actual "average" pitch is less than 43 inches and slip at cruise is higher than estimated. My guess is pitch is actually 40 and slip at cruise is 20%)
Running with the 43 inch pitch produced great acceleration and max rpm of around 5100 but the engine still showed signs of excessively rich mixture. After making the pitch adjustment, I used the Tillotson precision adjuster to go back to my earlier 1 1/4 (1 rev +7 marks) out idle setting and 1 1/8 (1 rev +4 marks) out high speed. (essentially this was a reduction of 1/8 turn for the high speed jet.) The Tillotson tool works great and allows adjustments as fine as 1/30th of a turn. This still did not produce desired results.
I then proceeded to estimate ZERO ROP be leaning the HS jet. This appeared to be at 1 +1/30th. I then richened the setting 5/30th to 1+6/30. (Slightly leaner than the "original" setting and most probably near the ideal 150 ROP setting.) To eliminate the the "four stroking" in the 3000-4000 range, I leaned the idle setting from1+7/30 to 1+3/30. Later flight testing indicated that a 1000 ft change in density altitude requires a 1/30 change in the high speed jet.
At this point, mixture adjustment of the high speed jet will probably need to be governed by CHT/EGT readings as well as spark plug condition.
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| Earlier Baseline |
Final settings:
The plane is FINALLY “ready to fly” after 4.5 hours of engine run-in, dialing in and crow hopping for the pilot to be ready to fly this particular plane. Crow hopping is really “low altitude controlled flight close to ground”. This insures pilot is familiar with plane’s characteristics while in the critical ground effect during landings…controlling descent rate with throttle as well as elevator.
Some “small” changes in preparation for first real flight.
First, my Garmin VIRB Ultra required a special housing to mount it in a way that it’s view is adjustable. Somehow, I lost the factory version and Garmin discontinued accessories when the stopped production of the VIRB a couple years ago. Fit my crow hopping, I mounted the camera on the yoke but I had to orient it vertically, missing out on the view of the Hall air speed indicator. I recd a new housing from a Chinese producer and made a bracket so that the camera could be mounted horizontally. The added height allowed the camera to be a sort of yoke position indicator as the “sight picture” changes—nose level puts top of camera in line with bottom of tach—yoke back too far brings nose wheel arm to come into view.
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| Yoke level flight |
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| Yoke back (nose up) |
I also added a “yaw string” as a redundant yaw indicator. Yaw strings are more sensitive than inclinometers and are viewed “heads up” without having to look down at the panel. The yaw string points in the direction from back to front to the rudder needed to reduce yaw--same rudder that "step on the ball" indicates on the inclinometer. I later shortened the string so that it hung from the mast without dragging on windscreen,
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