As can be noted, construction is finished and its ready for sanding and
covering. Plans are to use a white tex covering and trim with
yellow and black paint.
Note: something worth noting is the installation of the wind screen. Previously I've had trouble with wind screens. Getting them secured without too much glue is a struggle. Discussing this with others at the field, I offered why not a couple of tabs when bent back offer small screw locations that then just leave the aft corners to be secured by glue or a surface screw. Another modeler said, why not tabs there too but instead of screws, cut slots in the deck for the tabs. Had he done this before? No, but its worth a try.
It worked great! All that was needed was a little epoxy on the tabs from inside (three inside plane and two inside cockpit) and a piece of color matched trim tape around the base.
Note: something worth noting is the installation of the wind screen. Previously I've had trouble with wind screens. Getting them secured without too much glue is a struggle. Discussing this with others at the field, I offered why not a couple of tabs when bent back offer small screw locations that then just leave the aft corners to be secured by glue or a surface screw. Another modeler said, why not tabs there too but instead of screws, cut slots in the deck for the tabs. Had he done this before? No, but its worth a try.
It worked great! All that was needed was a little epoxy on the tabs from inside (three inside plane and two inside cockpit) and a piece of color matched trim tape around the base.
Phaeton Flight Testing
I'd still rate the power as realistic rather than performance... so no surprises but at current settings, it does perform acceptable aerobatics and will be a fun flyer. It should be a blast to do touch and goes in light air. I don't know the size of the motor but it's not a large string trimmer motor (guessing 18-22 cc) and is very economical on fuel. A 14 oz tank yields a long flight with plenty of reserve. Typically it takes about a dozen pumps of the fuel bulb to fill the tank and so far refills after a good length flight have taken 3-4 pumps.
After about a dozen flights, the prop settled on is a 15-8 yielding 7,400 rpm. I believe now that the motor is only about 18 cc and that a little larger motor would kick the performance envelope a good bit. A 15-6 prop yielded all noise and no pull at 8,000 rpm.
The plane required one iffy click of roll trim and about 6-8 clicks of down (which means I get a pat on the back for building without any warps in wings). It sets up fairly well for landings with perhaps a little too much tendency to float but without need for elevator adjustment until flaring. Likely, some shims will be added to reduce the incidence of the upper wing slightly, which might correct the need for down trim and help kill a bit of lift on landing.
On the second outing, 1/16" shims were placed at the upper wing rear strut locations to decrease the incidence yielding positive results with about half of the downtrim removed and a little better settle on landing. 1/8" will be tried the next time out. 1/8 reduced the amount of downtrim on the elevator to 1-2 clicks from center. Rolls got smoother and only a very slight amount of down elevator was needed for inverted flight. Landings were smoother with better stick. The magic spot may have been found but 3/16 shims will be tried. 3/16 put the elevator at neutral trim. Still no wing stall issues or bad behavior and inverted flight takes only the slightest bit of down elevator. Landings are smooth and the shims will likely be glued in place after a few more outings to confirm all is well.
The lower wing is 0 degrees incidence and I think I started with +0.5 - 1 degree on the upper and it must certainly be approaching 0 or perhaps even have become negative. With elevator trim now nuetral, incidence readings will be taken and posted.
Getting altitude and slowing to a crawl yielded no tip stalling tendencies on any of the settings. At the first incidence setting, the plane displayed a marked reluctance to roll upright off the top of a loop and will require curl under altitude when inverted unless it will roll the other way from the way I tried... but full aileron and rudder wouldn't roll it up. The plane might benefit from ailerons on both wings. The reduction of incidence in the top wing has helped but not eliminated a sluggish roll out of an inverted attitude. Aileron throws have been maxed and given an exponential curve.
Tracking through loops can't yet be determined due to buffeting windy conditions on all three outings so far. There is a hint that the plane wants to drift right slightly in loops... but again, I can't be sure yet as I've not flown it in still air. The plane rolls slow but respectively and once the carb was tweaked has acceptable vertical. It performed spins without effort and offers a nice snap roll though the rudder is wholly inadequate to support any knife edge flight. The rudder does turn it very nicely near stall for a crisp wing over stall turn. Cuban eights and Immelman turns are easy. Inverted flight requires a bit of down elevator and is slightly sluggish but if speed is kept up, the plane will perform an outside loop (very high!).
Balance seems to be close... the nose needs little attention when slowing for a landing nor does the tail fall or rise on the top of loops when things get slow. I followed an internet comment of a builder who shortened the nose 1.5 inches when using a weed eater motor and seemed to have hit the balance point really well as no weight has been added yet to alter balance. On the second outing, the plane displayed complete hands off flight from one side of field to other.
Liftoff and climb out is quite realistic and gets oohs and ahhs by the spectators, it seems the two degrees right thrust was about right... climb out is very straight with rudder only needed to deal with cross wind.
The plane is well mannered on the ground (the best I've experienced) with plenty of tail wheel weight to avoid pitching over on our rough field. Ground tracking is straight and requires little rudder unless dealing with a cross wind. With neutral elevator the tail comes up with no nose over tendency and take off requires elevator to break from the ground.
Landings are a bit of a challenge because the amount of head wind plays big. With a fair headwind, it requires throttle to near touch down but without headwind, even a very slow idle will yield a long floating landing. One landing in no wind, the motor quit about fifteen feet elevation and without prop drag, the plane floated 2/3rds down the runway before settling. Deadsticks will be tough... if they are into the wind, she will be hard to get back to the field and downwind difficult to keep from overshooting. If she is stalled a little too high, the balloon tires and spring loaded landing gear bounce her back airborne. Stall landings are not overly difficult to stick however and wheel landings are easy because the plane tracks very well. Her size makes her vulnerable to cross wind drift where rudder is needed but easy enough to feed in and without elevator it yields no roll.
A word about floaters and landing them. Because of larger wing areas and slower speeds of floaters, cross wind landings can yield a significant ground effect roll if the leeward wing is low that can make for some excitement and require quick roll recovery to keep from catching a wing tip. I think what happens is that when ground winds get trapped and can no longer clear easily under the leeward wing, pressure increases to accentuate a leeward roll. On these planes, much better than quick roll recovery is the importance to keep wings level during a cross wind landing using the rudder to adjust track drift.
Problems
A new plane offers the potential for problems and two can be noted. First, the clear coat used is not fuel proof. I used Rustoleum enamel paints and the clear coat is softened by the fuel and requires final clean up with a bit of alcohol, which removes the clear coat from the tex covering or at least some elements of it. Over a period of several outings and clean up with acetone, the clear coat should be gone and clean up easier
Attempting a third flight on the first day, a pull pull rudder cable was discovered broken loose from a solder joint, which ended the flying unfortunately when I was having fun.
On the second day out with pull pull cable resoldered using a better technique, the rudder servo quit and the rudderless landing yielded a trip to the weed patch at the edge of the runway and a sigh of relief that the servo was not used on the elevator or quit hard over. All this got me thinking that the split push rod used on a single elevator servo should have been dual elevator servos and rods and I'm rethinking doing so.
The five digital servo and 1100 mah flight pack was new though well bench exercised and cycled. A range test with motor running proved ok and the only radio concern was the one jittery servo put on rudder, but I've also seen new jittery servos settle down. I've been fortunate and never had a previous servo failure and was lucky here.
All in all... I'm happy with the plane and its flight. This is my first gas powered plane and the experience so far is positive. Not only is the motor economical to operate, it was free and only required a carb kit and some time and scrap aluminum to convert. It makes a reasonable match up to this plane. The motor exhibits only a bit more vibration than a model motor.
On the 4th outing, the carb fouled a bit and displayed a hesitant acceleration and required a cleaning. I chose to remove the screens and add an exterior filter. The gas engine doesn't yield as much oil residue as a glow engine but what is there is dirty. I'd not hesitate to do another gas conversion on the right airplane though I think the weed eater size would be my cup of tea as I'm not wishing to get into the expense and hauling challenges of very large airframes and heavy duty servo trains.
Landing Gear
The gas conversion and tex covering added weight to this model overwhelming the gear struts. A fairly simple fix was to add a spreader of 1/16 inch wire cable making it up with wire cable locks. It consist of two pieces with loops on ends with the outer loops hooking the axle and looping inside the V made by the joint of main and aft strut brace and the inside loops connected by a small but stiff spring. This allows the cables to be made up and then installed and connected by the spring. The spring and cable locks are covered by heat shrink giving the appearance of a bungee shock. The spreader cable crosses about one inch above the wheel axles and clears the ground well. I think I have 4" Du Bro air tires so the cable is 3" above the ground.
A few months later....
I've finally settled on a 16-6 prop running at 8,000 and upper wing shims of 1/16 and am fairly happy with the plane. If building again, I'd not use the heavier text covering. The Phaeton has the wing area to handle weight and fly realistically without difficulty, but vertical performance modelers often enjoy is restricted.
As to the gas conversion... it has run without any hiccups and is an economical way to go. I've twelve bucks in the engine (a carb rebuild kit). It uses 3-4 ounces of inexpensive gas/oil mix per flight. It starts very easy with a regular electric starter and idles great.
The cowl could not be fitted with the gas engine without going electronic ignition because the magneto flywheel doesn't quite clear. I might change to EI or mold a slightly modified cowl (someday).
Last... while the Phaeton offers the best ground handling manners of any plane I've owned, she also has the most pronounced variance in runway needed. If no wind, the takeoff run is long and landings require a very shallow glide slope with a low idle. In a breese, she will get airborne much quicker and lands with a very steep glide slope.