Shoestring flights - I brought it home! Now, can I do it again?

Mark Boesen wrote:The reason i ask i was curious about launch rpm of the 10x4 as it wasn't that much off, a little richer and you'd probably be ok. That's why i was asking what the launch RPM was and lap times with the 10x4 to compare it to the 9x5.

I should have written the rpm down. I can get lap times from the video, which I haven't done yet. There are more things I shoulda', coulda' done, like be more relaxed and try not to force it. I didn't bust the 10x4, so it'll be in my box next time I fly, and I'll give it another chance. I also have an APC 10x4 that deserves a try too.

Mark Boesen wrote:Your first attempt wasn't that bad and you've probably noticed by now a difference in flying the pattern vs. random maneuvers and somehow its become harder?...

No kidding, it's harder. I always thought I was so hot flying freestyle, but precision stunt shows me where I really am. So I've got a good goal to work on.

Rusty,
I've been taking my Goldberg Shoestring out to the circles with me on Tuesday nights, and trying to get some time on it. Mine has an old Fox .29, flying on 58' lines. I'm nowhere near the level of aerobatics (stunts, maneuvers) that you are performing, but the other guys that have flown it, say that it is set-up correctly, now. I run 5% fuel with extra castor added, and am still trying to get a consistant run. Unpredictable engine runs don't quite give me the confidence to attempt many variations from straight and level flight! Keep an eye peeled, though-I'm about to unveil the S-6. It's pretty! Also, I'm still struggling with the Nobler. I built a .15 size plane, that actually works, and it's been a real help to get me going stunty! I have still not completed a lap inverted.

You are doing good. It would be fun to have you join us, here. We have concrete circles, so inverted landings are kind of forbidden. Ha ha.

You know if you, Rusty, Kim, Ron, and whoever else wanted to get together and go flying, i'd get off my butt, dust off the planes and meet you at the field!!!

It would be a blast for sure. Problem is it would be a driving trip and we are pretty spread out.

Yeah, we can just feel lucky that the forums brought us together. I know I do.

Now, since we're all here, check out my newest signature song. This one always makes me smile. And it is accompanied by a great slideshow.

I flew the full beginner pattern today. Yes it was ugly and some of the stunts were aborted before finished, like my squares. I had trouble stringing two of them together. Even my loops were not very good. But at least I would have gotten points for a full performance. I'm still baffled at how hard this is to do correctly. I did manage a double OH8... sorta. My horizontal 8 in the video is a single too. I don't even know how many flights I flew, but only recorded one. I was doing my last flight of the day, in the middle of an OH8 when the lines went slack. I barely recovered it with a hard yank, and managed to pull out and level off inverted... my muscle memory is improving... when my UP leadout loop popped. Several loops later she pancaked inverted and broke the rudder off, and both prop blades. It was time to pack and go. That was the plan already.

Wayne says I'm coming along well and it's uncommon for a beginner to get an attempt at all stunts by the second lesson. So I guess I should be happy, but I'm my own worst critic. Wanna guess the hardest part today?...There was not enough wind. It was hard to tell where it was coming from, and a light breeze still screws with the tracking a lot. I've done prettier loops and such with a stiff breeze at my back.

So she gets new leadouts, and the rudder just broke where it had been broken before. No serious damage. She's a tough old bird, thank goodness, 'cause I'm sure punishing it. I'll post more later. I'm shot now, and felt the need to first spend a half hour writing a post on fuel/castor mixture before I got to this.
Rusty

Rusty, the main thing is being able to do it again. Timing is the critical factor of a square. Just think of it as a loop with four corners on it. For the inside square, fly level, then give up elevator, then return to neutral, then give up elevator, then back to neutral, and it repeats until finished. The key is in the timing. This is where too much elevator control can overcontrol the plane. Wind can be located when you pick up your handle to fly. Grab a handful of grass and toss it in the air as your placing your thong on your wrist. At least you will have some sort of indicator if no flags are present. Ken

Ken Cook wrote:             Rusty, the main thing is being able to do it again. Timing is the critical factor of a square. Just think of it as a loop with four corners on it. For the inside square, fly level, then give up elevator, then return to neutral, then give up elevator, then back to neutral, and it repeats until finished. The key is in the timing. This is where too much elevator control can overcontrol the plane. Wind can be located when you pick up your handle to fly. Grab a handful of grass and toss it in the air as your placing your thong on your wrist. At least you will have some sort of indicator if no flags are present. Ken

Actually squares are about my best maneuver, when I stretch it out big enough. I fell back into my bad habit of too tight in the flight in the video, but I did make some good ones in other flights. The OH8 in this video is my first ever attempt with the SS, and it was pretty bad, but I flew through it. The one in the last flight of the day fell apart and went slack. That's when I popped my leadout. I haven't trusted those since day 1. I should have followed my gut and replaced them. The Yak won't have that problem.

Hey Rusty,

Second time through the pattern. You have it down and all that's left is to make it look real pretty. You may not see it, but you are improving. Your doing overhead stuff now. It probably feels like you are going back to basics, but you aren't it's just new is all.

Keep plugging away! Looks like I have some work to do to catch up!

Ron

Something I forgot to mention. Last week I flew with the new tank that Mr. Brodak sent me to replace the one that was passing bubbles from the uni vent into the pickup. The new one works great, no more 6 or 8 lean laps normally vented before it runs out. That's handy for sport flying when you don't keep track of your fuel usage. But for pattern flying, uniflow makes it nice to just have it never change, and turn off when the routine is done. I'm over filling it for now since I like to go back and repeat some stunts I busted, but when I start to really get the hang of it, I'll figure out exactly how much fuel to crank up with.

I started out the day with a Top Flite 10x4 wide prop. The lap speeds were comfortable and I was able to get in and out of stunts at a nice moderate speed. I was closer to what I want without having to run the engine too rich. When I landed after that flight, I hit an ant hill and busted it. I replaced it with a newer Top Flite 10x4 and it was faster... uncomfortably so That's what I was flying in the video. I had an APC 10x3 with me but was doing well enough and decided to quit changing things on every flight, so I stuck with the TF. But since it's busted now, I'll try the APC next time. I wish MA made a 10x3 but they don't. I might try one of their 10x4s, but I bet they are the new improved narrower versions.

Another thing I did today, at Wayne's suggestion is flipped the needle upside down so I could eliminate about 3 inches of fuel line from the tank to the engine. It's more dangerous to tune, but I think the fuel feed is better. If I remember correctly, Ken also suggested this back when I was fretting so much with fuel feed problems. So between what Ken suggested with the fuel line, and what Mark suggested with the prop, well, damn, I'm flying about right. I should have just done what they said to begin with, and I might be another month advanced by now. Sorry for my stubbornness, guys.

I tried the APC 10x3 today and it was faster than I expected. Started out in the mid 4 second range, but after launching a little richer I finally got it to a comfortable 4.9 or so seconds. Will Davis, one of the CDs at the Huntersville club made me a nice new set of 60' lines with copper wrapped ends, beautiful work, and that's what I'm sticking with for my contest practice now. The Thunder Tiger is a dream machine to work with. Eight choke flips and light the fire, it's as easy as that every time.

This pattern business is much harder to learn than I imagined. I'm obviously not near as good as I thought I was. But after a couple of trimming runs, I did a decent pattern that I think would have scored very well on everything but the OH8. Nice takeoff laps and a perfect wingover, my most consistent stunt of all. My Insiders were all in the same circle, good inverted laps and my outsiders were good and round. My squares are getting pretty consistent too. I have been having trouble with the horizontal 8s, but completed it with no emergency moves, that was a relief. I'm glad to get that behind me. It seems so easy, but it ain't nothing like doing a simple lazy 8. Then came the last maneuver, the OH8. I completed one 8 and thought I was on my way, but had to bail on the second one. My same old problem, too tight on the second pass and it tried to fall out of the sky. No yank this time and an easy save, so I flew it out and landed pretty well except a last second lift into the headwind uglied it up and I bounced a bit. I would have at least scored an attempt on the OH8 and gotten my pattern points if it had been a contest. That made me feel better about my progress so far.

Wayne and I took turns, with him flying intermediate with his .40 Nobler. On the last flight of the day, I got something mixed up in my horizontal 8 and bottomed out, spreading the LG... again(I seem to do that every outing). Luckily I usually just straighten them and go again. But this was a hard one and it busted my 10x3 prop, chipped a rib and tore the Monokote under the wing. I haven't examined it closely yet, but there's dirt in the engine. I hope that chipped rib is all that's wrong. I was too disgusted with myself for doing something so stupid, that I just parked it in the shop until tomorrow.

I'll clean it up and see what she looks like. Wayne is going to bring his Ukey stunt trainer for me to try out next week. Maybe it'll help me tame this thing and handle the Shoestring better. I've said it before, the SS is a tough old bird. Thank goodness, because I'm testing its limits. So I guess this is the lesson #3 report. Maybe for my next report, I can keep it out of the dirt.

So, that's all for now.
Rusty

All in the pursuit of perfection Rusty. The SS will probably take a beating before it is all said and done.

Hope the damage is not too severe.

It's all fixed up except for the Monokote, which I'll do today. The Poor ol' Thunder Tiger was a mess. I was thankfully smart enough not to rotate the shaft before I opened it up, There was dirt piled on top of the piston, all in the crankcase, and a few specks I could see in the ball bearings. I took it all apart(not the bearings) and put it in a jar full of old Sig 35 and shook it up good and let it soak. Got it all cleaned out and it's clean as a whistle now. The front bearing doesn't feel 100% smooth without the crank in it, but there is no noise or bad feeling with the crank installed. I filled them up with air tool oil before re-assembling. I think it's fine, but I should get a spare set from Boca Bearings just in case. I'll crank it later today.

One more thing is, I'm going to put a T-nut in the tail so I can use weights to balance this plane right. It's always been nose heavy, and maybe if I move the CG back to the plans minimum, it'll be easier to pull out of the way of the ground when I open up a loop too wide... maybe... Of course, the best idea would be to not open up a loop too wide.  I'll probably have to get used to it. The nose heaviness might be why my wingover pullouts are always flat and perfect... the only perfect thing I do so far. But it might make the plane feel lighter and more agile.

Glad to hear it's all cleaned up Rusty!

All my planes are a touch nose heavy. Some airframes tolerate unbalanced better than others. Try it and see!

Ron

I balanced mine at the plans forward-most C/G. I couldn't tell a bit of difference. Since I busted my APC 10x3, which was running in the mid 4 second range, too fast, all I had was a 10x4. Bad idea. Wayne clocked me at 3.8 seconds. That damn Thunder Tiger is one ass hauling engine, even launching rich. But with APC's they always lean out in flight no matter how rich I launch. I'm done with them. My LHS ordered five 10x4 Master airscrews for me. He has one on the shelf that I'm going to go buy tomo... er today. There's no such thing as an MA 10x3.

Hoping I can go out Sunday. But first I have to re-cover the wings. The grass hadn't been mowed and it shredded my Monokote. I need to epoxy a crack in the elevator too. Trying to do 3 loops, I did it again... splat bottomed out. It's just too freakin fast. I did fly one mostly successful full pattern at that speed, but after that I was hot and fatigued and my reflexes fell off. The splat flight was the one I videoed, but see no reason to put it on public display. I was pretty [bleep] off about it... for a few minutes. I don't usually stay that way for long. Just that that's the kind of thing that keeps the Yak from being built.

I've been trying to get the speed right for way too long now. I'm going to put the muffler on and see if that tames it some. The narrow handle spacing seems to have made it worse, my wrist movements aren't comfortable. I think my range of motion might be less than non-arthritic hands, so I need the wider control back. I may change my mind after I slow it down. Early on, I was running an old now-unobtainable wide MA 9x5 sloppy rich with a 4-2 and the flats were slow, but as soon as I pulled into a stunt it broke wide open lean and stayed that way on the downsides. And the needle was quirky running that rich, so I abandoned that plan. So far I haven't gotten it right again.

Oh well, so it goes. I've been lying in bed trimming and flying in my head for two hours, so I figured I might as well get up and write about it. I've got the itch bad, I just can't put it together yet. If I can't go Sunday, it'll be late September before I try again. Going back to the beach next for a week for some more R&R and surf fishing. Hopefully I'll have a good Sunday flight report. I'll be by myself stooging it.

Rusty, if your going to use the stock muffler, this is going to prove to be problematic. For starters, the exit hole is too small. Many times in order for this part to come out of the mold the engineers use a draft angle on the part itself. The hole you see at the exit isn't the same size as the hole up inside. The exit hole appears large enough but the hole up inside is considerably small. It already sounds as though the engine is starting to runaway in or around the two minute mark. The stock muffler and I've suggested this early on will help if using muffler pressure. I would try muffler pressure to the fill vent and also on the uniflow vent. It takes experimentation. However, the stock muffler will retain too much heat and the engine may work or it may be off to the races within seconds.

Muffler pressure doesn't compensate for the head pressure in the tank. It may keep things at bay, but if the engine is overheating, it's going to runaway. It sounds as though your already launching dead rich and the engine goes bananas. I personally dislike 10" props on a plane of that size. I would use a 9" prop.  A 5 pitch prop is going to dramatically increase your speed and will also load the engine more especially in the maneuvers. This to me is going to do the absolute opposite of what your trying to attain. After re reading your post, I see your suggestion was to not use this prop. I didn't quite understand until re reading. A 9x4 is a better choice in my opinion.

It really sounds to me that this engine is doing exactly what many of the high timed  engines do when trying to run them for stunt. The solution is more exhaust area, larger venturi area, light pitch props, lower the compression.

Adding a head gasket or two could really help here. It will soften the break and keep the engine in a more stunt friendly mode. THe thing to not do is to not change to many things at once. A tongue muffler would be my best suggestion due to weight and free flowing. It's very easy to install a pressure tap within it.

Early on your engine was acting as though it was suffering from too large of a venturi area. You've since changed the tank and it now seems as though the fuel draw problem wasn't venturi related. Now I'm very curious as to why the engine isn't settling down throughout the run. Funny things happen especially with uniflow, and this can show it's true colors when the uniflow tube becomes uncovered within the tank. Cracks in the piping, bad solder joints, etc. Not saying this is the case, just some of my findings over the years. Ken

Hi ken, thanks for all the input. The muffler I'm using is much smaller than the stocker, and gutted. There's nothing inside of it, just an empty can of air. The HS sold the MA 10x4 that I went to get so I bought two TF Power Point 10x4s and an 11x4. Those were also fast last time I tried, but I'll launch richer this time. I wanted to ask, and I think you or someone suggested once to cut the 11x4 down to 10-1/2". I'm going to try that. I have yet to try another brand of plastic 10x4.

The engine doesn't change after half tank anymore. I'm blaming some of the leaning out after launch on APC, because early on when I was  using an MA 9x5 with a half decent 4-2(until the head pressure dropped), the APC 9x5 I tried refused to stay rich at all, it went lean right off, like they're doing now. I do have a new style narrow MA 9x4 and an old wide 9x5. So I haven't written them off yet. I'm going to try and get an early start tomorrow and hopefully have some time to test before I start sweating and get tired. I don't do well when tired and hot.

Hope everything works out well for you tomorrow. Can't believe they sold your prop!

I Spent the afternoon flying in 100 degree humid weather. Besides being stupid hot, my runs were either screaming lean or sluggish and rich. I could not needle the old Fox for beans and hot restarts....forget it.

I finally did some overhead stuff with it when it ran right. I was wondering if the porky Ring (34oz) would even stay up there and it did luckily.

Anyway this is your thread. Good luck tomorrow!!!

Ron

Hi Ron.
Nah, if it's about flying stunt, post it here. Is the Ring the one you're going to fly in the contest? I was thinking it was the Clown.

I got the SS all fixed up. I got tired of working on it and patched the wing with packing tape. Upon further inspection, it looked a lot less like Freddy attacked it. It was just my crazed post crash imagination thinking it was worse than it was. I'll re-cover that whole wing before the contest, and put new numbers on it. I also put my new Brodak LG on it. Looks pretty good except for the tape. I hope the guy that didn't mow the field is there to see what the grass dod to it.

It now has a muffler and a 10.5 x 4 Top Flite woody on it. It's back to being nose heavy with the muffler, but I couldn't tell any difference when it was balanced anyway. It's about 3/8" forward of the mark. The other day I was launching so rich, Wayne had to pinch the line a couple of times while I was walking out to the handle. If I stooge fly, I guess I'll have to run. 

How's your pattern going, can you do all the stunts/attempts in order? Do you think 1/2A practice helped? And when is your big day?

Rusty

Long grass is nasty stuff to fly on. Just hand the guy your SS, iron and ultracote and walk away without saying a word  

I have a feeling you won't even notice the muffler. In some situations being nose heavy helps anyway.

I plan to fly in 2 events OTS and profile. I chose the Ring for OTS as it is not flapped. That way I won't lose the 40 bonus points.

I may do the Clown in profile, we shall see as the event draws closer. I can do all the stunts except the overhead 8. That is to say I can do an overhead 8, but not from a wingover. My wingovers suck so I have been working on those. Maybe once I can do a clean one I can work in the overhead.

My biggest shortcoming is not opening up my stunts. The reason I believe is due to 1/2A I have more sky to work with, but at times I fly like I am on 35' lines. I am to the point where I get it right more often than not. I am lucky as I am allowed to have a helper call out the stunts during the event. That might be something to ask the CD for your event.

The event is 28 Sept in Tulsa OK

Ron

My son would stay in the circle with me and he would count the laps andmaneuvers. I have to say it worked and it becomes very helpful in terms of where to start your maneuvers. He would say for instance, on this lap your going to do this maneuver. Ken

I did it! Good speed, good flying, and it runs sweet with the muffler and the TF 10.5 x 4 prop.

Details and some video later.

And there was an Apache on the field that had made an emergency landing, so I entertained the service detail while they ate lunch. No unplanned landings.