Question about trimming my CL plane

Guess Keith beat me to it!

lol,, tie finish Ron.

One thing I can add with doing maneuvers in stunt. I've also judged beginner and intermediate stunt in local competitions. Where and how you start that maneuver is critical. Starting too high results in a ellipse, while too low results in a quick jerk of full up elevator to avoid terra firma. Either case your strangling the plane. If your stating that your plane is loading during maneuvers, is the prop too much pitch or is the needle set to lean? Even in your situation, 20 deg elevator seems more than adequate to me. You now have to ask, is the plane nose heavy? If you were flying it prior and the plane was too twitchy, was it due to overly fast controls and controls that were giving too much throw ? I recall you added noseweight. Was the tail heavy condition due to my above statement, or is the handle spacing too great? I've even used a .35 size Luxon (large) slide clip to gang my handle wires together to close the wire spacing down just to try it. Most flyers doing consecutive loops generally go the opposite of what is happening to you. They keep getting tighter and tighter until they strangle the plane. Your arm needs to lead the plane. Holding up elevator and just letting the plane do loops is certainly going to bleed off speed and load the engine. This is another reason I try to have the plane trimmed with no rudder offset or engine offset. Proper line rake of the leadouts combined with speed will satisfactorily do this automatically. Typically however, I end up with slight engine offset for final setting due to flying upwind situations.

Pilots should look like their doing some kind of ballet dance in the center of the circle to someone who's never witnessed C/L flying. Leading the plane with your arm requires very little elevator control which keeps the speed consistent. Stiff arming with a bent elbow is going to keep your plane from flying it's full potential. Pilots should also be taking small steps backwards after each loop. This will get you out of the turbulent air your wings and prop just stirred up. Turbulent air can not only seriously slow the plane, it can wreck the plane. I've had this happen in 1/2 A combat which was result of the lead plane while I was following. In my situation, it can lift the outboard wing violently losing line tension and can inherently cause a crash. This is more likely to happen with a large stunter, it will happen with 1/2A as well. This is why dead calm air isn't always the best air to fly in. In my honest opinion, the Flite Streak flies far superior on the fast side then it does slower. I feel it's a harder plane to fly stunt with gracefully as it quickly maneuvers. Again, these are my observations. If your not already trying the Cox 5 x 3 black I highly suggest it. The Cox 5x3 black non safety tip or competition gray just seems to be a happy honeymoon on the Tee Dee. Any larger prop is going to load the engine. A 4 pitch prop is going to load the Tee Dee in a maneuver. Although some may claim that the 5x3 is too small of a prop, it keeps the engine in its max hp maybe even exceeding it in level flight as it unloads. The advantage to this is, when the engine does indeed start to load and the rpm's fall off, it places the power right at its max in the torque curve driving the plane steadily through the maneuver. The other advantage is that a smaller prop with lighter pitch makes setting the needle easier. The disadvantage to this is you don't want the plane going a zillion miles an hour. This is where prop clipping comes into play. I keep a whole selection of Cox rubber ducky's. I have them from full size 5x3 to 3 3/4". I use them for a variety of planes including the Tee Dee. My props are cut down in 1/8" increments.As the prop size on a Tee Dee approaches 4 1/8" it almost becomes useless as its just beating air and making too many rpm's. I found anywhere from 4 1/2" - 5 to work the best on Tee Dees. Obviously, longer lines would help as it would slow the lap times, it will also allow the engine to run in its happy state. Norvel's are more forgiving and they can really keep turning up. Just to add something else to look at, especially after a doinked in landing, check to see your engine hasn't tweaked giving you downthrust. Ken

I'm going to re-read that and look at my only video before I reply. It gives me a lot to think about, plus I need a few more flights before I draw any conclusions. Unfortunately my flying has been on hold for a couple of weeks and will be until next weekend. When I get back to flying I can get a steadier video to look at too, as I don't have anyone to watch me fly and point things out. I am using a 5.5x3 MA prop and I can hear the engine slow in the loops. The plane was twitchy and unstable before I added nose weight. It would not fly a flat circle. With the weight it is balancing at the point the plans suggest, which is less than 1/4" forward of where I maidened it.

Thanks. I'll get back to it. Right now, after reading your post, I'm thinking the prop is the best improvement I can make while I'm still using the Tee Dee.

I would also like to add an additional comment. Too many times I've done this. When making changes, make them subtle. Doing and changing too many things just makes a disaster out of trying to figure out what exactly is the problem. My son experienced this yesterday as I suggested to fly the plane in the nose heavy condition it was in. He wants to punch holes through the ozone layer all day long and wouldn't have a calm steady flight. So the tail weight went on and once again, I suggested to fill the bladder 1/4 way full but noooo he wants to show me how its done. Well he had his hands full on one wild ride which resulted in the plane crashing when the power cut due to the floatiness of the plane. He got caught upwind with a tail heavy plane.

I like the simpler approach of short flight mild changes. Even something as simple as a handle change can make quite a difference. What works for one person certainly doesn't always work for another. Your suggestion of a prop change, and I would try multiple props if you have them sounds like a great start. It also familiarizes you and the props, plus the engine capability. Having some extra venturi's is another aid in tuning. Having the stock and a few others opened up. I keep about 3 in my pitbox. In the event your settled on your current prop, try a larger venturi to see if you can get a bit more power out of the engine. It's a simple quick change. Just remember to launch a bit richer with a opened up venturi. Sometimes you often need the engine dead rich on launch. This probably wouldn't be recommended flying from a stooge. One thing to try if you already haven't tried this is to use stainless lines. I used to fly Tee Dee's on .008's but I had one line break and since switched to .012's. The responsiveness from those lines are far superior to Dacron and the line drag is much less. If your flying by yourself with a stooge the longevity that you would receive would be far greater than people walking on them. I have to use caution with my 1/2A equipment at my club as I have several members who just don't realize the importance and care of .012 lines. Ken

RknRusty wrote:I'm just wondering about something. My Baby Flite Streak does almost everything right. It keeps the lines tight, even in an unpowered glide, and makes snappy flips when I turn it upside down.

From this I am guessing that the airplane is balanced correctly.

What I want to know is if all planes' loops grow during a multiple loop set. Like if I pull full up and hold it for several loops, the first loop is a certain size, the second is a little wider and after the third it's close enough to the ground that I don't want to risk a fourth, so I level off and go around again before the next trick.

First, you are probably stalling by pulling full up. Try to actually fly through the loop as opposed to hanging on full up and hoping for the best. BTW, I think that's how ALL of us did our first loops.
:-)

Now, does that mean I may either be slightly tail stalling or either don't have quite enough throw? Stalling would be my first guess, but I don't have much over 20 degrees of elevator throw, maybe 25.

That should be enough movement. You should check that both up and down movement are the same. Also check that at full deflection, you are not putting extra force on the elevator...just deflection. While you're checking, make sure the pushrod can not flex. Move the controls so that the pushrod is in its rearward position and see if you can easily move the elevator toward neutral. If it flexes, you may need a pushrod guide.

Your loops should start about 3 or 4 feet above shoulder height. Make your loop as round as possible while ending at the height you started. When you get used to them lower the starting and ending height to shoulder height.

When you get good at the loops you may want to give it some neutral then down as you go over the top and do a figure eight. When you can do consecutive figure eights, you can stretch them out and fly inverted and do outside loops.

But I digress...check your balance and control system first. For props, for a standard TD on suction (non pressure tank), the venturi is a bit big so you need to keep up the RPM. I would suggest trying an APC 6x2 if the 5x3 doesn't work well. I think, however, that you will find it easier to do consecutive loops once you areactually controlling them and not stalling.

Keep us posted and good luck.

George

Just like a real plane,, well like my dads full size Citabria, we would gain a bit of altitude so you can get a run downhill before pulling back, build a bit of extra speed on that first loop so the rest are pretty close. A loop from the flat and level is from the set full speed it can attain, the first one is nice and tight because you have that speed, then the rest degrade pretty quick and you start to "belly out" as Dad put it. We would take the old Citabria right to the NES speed on the downhill run on those loops, because he didn't have a inverted oil system we had to hold a fair amount of G's thru the loop. To much "held inverted" flight and it would puke oil out the engine breather and coat the underside of the fuse. Me being the smarta** son suggested running a tube the full length of the fuse from the breather to exit by the tailwheel. He thanked me later,,lol.

Ken Cook wrote:I would also like to add an additional comment. Too many times I've done this. When making changes, make them subtle... I suggested to fill the bladder 1/4 way full but noooo he wants to show me how its done. Well he had his hands full on one wild ride which resulted in the plane crashing...

Sounds like me. I knew my plane was built so well it would fly perfectly even though the CG was 1/4" farther back than the plans indicated. I knew I was good enough to hang on if it was a little squirrelly. So I pumped 3/4oz of fuel into it and launched it. And now it has a an epoxy and fiberglass cloth repair on the fuse from whopping its belly on the 72nd unplanned rapid loss of altitude.

gcb wrote:First, you are probably stalling by pulling full up. Try to actually fly through the loop as opposed to hanging on full up and hoping for the best. BTW, I think that's how ALL of us did our first loops.
:-)

Yes, and I still do, not knowing any better.

gcb wrote:(20 deg.)should be enough movement. You should check that both up and down movement are the same. Also check that at full deflection, you are not putting extra force on the elevator...just deflection. While you're checking, make sure the pushrod can not flex. Move the controls so that the pushrod is in its rearward position and see if you can easily move the elevator toward neutral. If it flexes, you may need a pushrod guide.

Checked, checked and checked. I have a guide brace attached to the fuse for the rod to pass through. I also had to add a stop by soldering a wrap of copper wire on the rod that won't pass through the hole in the guide brace. It's very stiff wire, no flex at all.

I did all this while it was still being built. I had allowed more clearance for the bellcrank in the down direction, so I added the guide and stop. The throw is exactly equal in both directions, as measured from 0 deg.

gcb wrote:Your loops should start about 3 or 4 feet above shoulder height. Make your loop as round as possible while ending at the height you started. When you get used to them lower the starting and ending height to shoulder height.

When you get good at the loops you may want to give it some neutral then down as you go over the top and do a figure eight. When you can do consecutive figure eights, you can stretch them out and fly inverted and do outside loops.

I will work on flying the loops instead of forcing them. I usually do some figure 8s during every flight. The camera missed them in my video from Traveling Prop day, but you can see me standing still flying them. It's one maneuver besides loops that I have been completely comfortable with, but when the RR1 is running right I can stand still and fly the Satan as long as I want to. I usually do at least a double or triple loop on every flight too, as can be seen in most of my Li'l Satan and Jumpin Bean videos.

Here I am talking about being able to do this stuff, yet asking for help. But as you pointed out, I can learn to do rounder loops if I learn to fly through them. I wasn't sure what a perfectly set up CL plane should be capable of. I'm at a disadvantage, never having had a real world friend that knew anything about it. I always showed them how to fly with no tutoring for myself.

gcb wrote:But I digress...check your balance and control system first. For props, for a standard TD on suction (non pressure tank), the venturi is a bit big so you need to keep up the RPM. I would suggest trying an APC 6x2 if the 5x3 doesn't work well. I think, however, that you will find it easier to do consecutive loops once you are actually controlling them and not stalling.

Keep us posted and good luck.

George

I will try some props. I have an APC 6x2 as well as a 5.5x2.5, and as many Windsor MA 6x3s as I need to cut down. I've made some 5s, 5.25s and 5.5s out of them. Next time I go out to fly, my plans also are to go up to 40' lines, up from 35'. I'm not running on suction, I'm using a pressure bladder.

Since I've been grounded I've relived my only non-shakedown flight of the Baby Flite Streak and my other planes on YouTube a bunch of times. Trying to figure out exactly what I'm doing out there. At least I brought it home safely. I expect to be cleared to fly after Thursday. Meanwhile I just play in the shop and think up questions to ask you guys. I appreciate all of y'all's expert help.
Rusty