cannot do Lazy 8s or Inverted with plane

I have to ask, does the plane fly well until you start trying to do a consecutive maneuver? A wing which is not symmetrical is just a poor maneuvering wing by design. As Jim mentioned, incidence issues could be the problem but overall I see a extremely draggy plane with little wingspan.Based on the picture above, I see too much elevator control which is acting like a air brake vs a elevator which will drop the plane out of the sky and cause it too stall. I see too much throw due to the pushrod being in the incorrect hole on the bellcrank. When the pushrod is pulled for up elevator it's less likely to bow whereas you have no support on the pushrod which will bow when inverted due to it pushing. In addition, the gap between the stab and elevator is extremely large which greatly reduces it's effectiveness. One other thing I see is the angle of the pushrod to the fuselage.

The pushrod being on a angle like you show in the pic can twist the fuselage at the same time as it's operating the elevator under load. This may have nothing to do with this situation. Why build a factor into the plane though? Move it over and make the pushrod parallel to the fuse which allows a pushrod guide to be installed without binding.

Any stunt pilot will tell you the key to success is keeping the speed up. Introduce a short wingspan into the equation and the engine now has to work even harder to do this. This is why rudder offset and engine offset is a poor way to maintain line tension. I see your leadouts swept back which appears more than I would prefer but I don't know this design but nonetheless, I personally would have them moved forward to the leading edge. Having them back strangles the plane causing it too slow down in the maneuvers you need the speed the most.

The problem with this scenario is that we as modelers change too much at one time to try and resolve the situation. Issues like this should be addressed one change at a time. However, in hindsight, another factor can be at play here. When one starts introducing maneuvers into the flight, there skills are increasing beyond the planes capabilities. If your looking at flying maneuvers and doing it successfully, these are not the planes to do it on.

F2D wings use bladders, if your not familiar with using bladders, I suggest you get acquainted with the process. Neither the Enya nor the OS can adequately use bladder pressure on the stock needle assembly. The Enya .15 is very timid but it can swing a 7" prop fairly well. A 7x4 would be my suggested choice at first. Using anymore pitch will severely bog the plane in the corners. These planes like consistent speed. Your engine choices are going to be a bit more heavier than what was spec'd for them. I do a few things such as making the elevators out of bass and I tape quarters to the covering at the tail using clear packing tape. A small prop allows for better turning vs a larger prop due to the gyroscopic forces the larger produces.

Don't use line clips with these planes as they will jam up ultimately crashing your plane. The leadouts usually have hooks with a piece of tubing. I like to double loop my steel lines at the terminations and when I use Spectra, it's a single loop or small split rings. Just some FYI on line length, F2D line length is 52'-3" with a + or - 1". This measurement is from center of handle to center of plane. For starters seeing that your engines choices are a bit anemic for the plane, I would start with 52'. You can always shorten them. This doesn't mean that your lines themselves are going to measure 52'. Center to center taking into account leadout wires and 1/2 the span of the wing.

When we fly with 25's, we use 100 lb test as the rules indicate. The breaking strength of these lines are the equivalent to .018" steel. Seeing that your a .15 displacement, these fly on .015'" steel. I see no reason why 80 lb Spectra wouldn't suffice here leaving way more safety margin then needed.

What OS.15 are you planning on using? The steelfin OS was a fairly stout runner for what it was. The following generation all aluminum .15 doesn't offer a whole lot of power. The FP .15 in my opinion is a terrific choice and we were running them at 20K using 7" props, no venturi and 35% nitro. The LA .15 in my opinion doesn't match the performance of the FP it replaced. It's remote needle valve will work with bladder pressure but it's taper is incorrect therefore it can't lean out properly like it needs too.

For your initial flights, I would add additional tip weight to the outboard even if you see tip weight inside the wing. I use quarters which is almost 6 grams a piece. I start with 2 taped on the outboard wing. Clean with alcohol and use a fresh piece of tape over it. Remove if the wing is excessively dropping.

One problem with wings is that many don't understand how to launch them. If you have a launcher to assist you, the prop is close to the leading edge and one can't see it spinning. The launcher needs to understand where to place his or her hands. Colored tape on the leading edge keeps hands out of danger. One should just cup the leading with their hands and just open their fingers. Many times fingers catch the leading edge which rotates the wing vertically and it's game over for the inexperienced.

Gary, there are all different varieties of line clips. Some much better than others. I probably should've stated not to use Luxon slide clips. They're the largest, most common, the weakest and the easiest to become jammed. I use them all the time due to convenience. That being said, they could be used if you slip tubing over top of them. Using tubing over the connection is standard in combat land. We do it at the handle and the plane end. I've become intertwined with my opponent before when he neglected to do it at the handle end which resulted in me wanting to choke him.

Diesels in general are not particular picky when it comes to tanks, glow on the other hand can be a bit more problematic. The only tanks I use on wings are for vintage combat which use baffle piston engines. These engine are not generally tank picky and height is the usual issue. Most vintage designs have the tank in the ideal location which is directly behind the engine. I've run into issues using the Enya where the tank pickup being outboard created a condition I couldn't resolve. No matter what I would do, the engine would just lean and lean all the way to the end which isn't good for this engine. The LA is very tolerable of this and won't succumb to problems that could occur like the Enya. Having a Enya that's not broken in it's entirety is also not recommended. To resolve some of this, I made the tank uniflow which helped but didn't work completely. I'm not certain of how the tanks are installed in the diesel F2D wings. I've seen them and I don't generally pay attention to them. Diesels stink so bad no one here wants you even to run them nor will they launch them so they're out. My son and I are the only users of diesels in these parts. My son mixes the fuel and his fuel doesn't stink like others. I believe it's due to the Klotz oil he uses and he also puts candle scent in the fuel.

I also feel your not doing yourself any favors by flying on lines at 45' long. These planes are hard to see due to their color, they can be twitchy, and they can get in front of you real fast. Flying eights in front of you can be the best way to fly out a flight if things become to dizzy or uncontrollable. This isn't a 1/2A, it needs breathing room and shortening your lines that much is really not the norm. We fly these planes many times eyes off. If you can't fly the plane without looking at it, it's not trimmed correctly. This means that if you have eye focus on the plane, eyes off, you should be able to continue flying it at the same elevation. If you have the plane at 45 deg high, you should be able to fly consecutive loops EYES OFF. So, if you feel your in trouble, pull full elevator and the plane will just fly loops.

The LA will turn up and I like to use lighter pitch props for this purpose. A APC 7x4 is a good beginning start but my preference is the APC 6.3x4. I've even trimmed a bit more off of the tips. The main problem with the LA is the remote needle valve is that it won't allow you to lean the engine to it's full capacity.The rear mounted version wants the fuel to always siphon back into the tank which causes hard starting without opening the needle again. This may not be a issue for you initially. I'm pretty certain the venturi switches from the OS to the Enya. If you have a larger Enya venturi, it may just offer you a bit more power without drilling out your stock one.