The Thermal turn and any other tips

[Hossfly72]

I need some advice please. I just got back into flying after a 10 year year absence and my skills are way rusty. I started with a Skeeter years ago and moved to progressively better ships, but always came back to the Skeeter. Well, this time I started with the Skeeter again but I've forgotten all of the little tips and tricks I used before to make it a great flyer. The new one is a lot lighter than the old ones thanks to modern micro systems and I built it pretty well. The trouble I'm having though, is that my turns are just REALLY slow and wide. The wing is set up with the correct polyhedral angles. I've moved the CG further back than I ever did before and it indicates lift well but I just can't turn tight enough to stay in it. I can't tell if it's me, or if it's the field where I fly or if it's the plane. The conditions in which I've been flying haven't been the greatest and the lift has been very light so I'm kind of hoping when I can find a real thermal it'll kick up on step and go. I know I'm flying too slow for a S3021 airfoil but I don't have enough altitude to build any speed. A highstart is on order to remedy that situation though and I'm looking for a new field in which to fly.
Will changing the wing incidence help and if so, please elaborate on what each change will do. Like I said, I've forgotten a lot of stuff. I've got very little washout in the tips. I did have more but I took it out and it seems to fly fine without it, but I could be wrong. I feel like a complete rookie again. The thrill is good, but I want a little more out of this plane before I work on the next one.

Thanks all,
Hoss

[dephela]

I'm sure you'll get a lot of help on your question but have you tried the "search" function in the forum? I got 23 pages of hits for using the term "thermal turn".

You won't find any results for me there though, I think there are too many fun things to learn through exploration and discovery.

[Hossfly72]

Been searching and have read everything at least twice. Still looking for more though.

[nuevo]

I presume you are saying the plane is not responsive enough in the turns.

it's possible that the polyhedral (I assume this is a 2-channel) is too flat, and/or the rudder is too small? Try taping some stiff cardstock or 1/16" balsa to the back of the rudder. Add 1/2" to the rudder back edge. See if this improves things. Just a shot.

[Hossfly72]

That's exactly it. But I can't tell if I'm expecting more than the plane is able to offer or if it's just a lack of altitude and speed that's hurting me. I suppose I should have said I was looking for plane-specific info from other guys who started with Skeeters. I've read the Charles River page about mods to the it and incorporated most of them. Just wondered if folks had more tips about the plane itself...

[dephela]

I'd bet that with more altitude you do see better results.

[schrederman]

Be sure that you have a full 30 degrees of throw in the existing rudder before adding to it. If it won't do a pretty tight loop, you may need a little more up elevator. I fly my 3021 Hawks pretty slow, and they don't seem to mind. I do use an aft CG, some say to the extreme. I've had it thermal out from a hand launch several times...

Enjoy.

Jack Womack

[Hossfly72]

Yeah, but Jack.... You live in New Mexico where big thermals grow!! LOL
I live in swamp central... I just have to wait to circle over an alligator with gas!!
I think I've got it tuned pretty well, but the small highstart is the answer. The longest flight I've had with it so far is 5 minutes and it flies pretty well. It floats beautifully stable, straight and slow. The rudder has lot's of turn on it but I think I'm just not high enough to get into some good lift and really hang it out. Every now and then, in a tight turn, it'll drop the inside wing and dive a bit but I think I'm just trying to turn at too slow a speed. I'll remember how to fly eventually, but I sure do enjoy reading words of wisdom and humor from everybody. It helps fight the boredom between flights!

[bfretless]

I've flown the dickens out of my Skeeter and have a couple of my longest flights with it. You definitely want all the throw you can get on the rudder.

You said you think you're flying it too slow, and I think you're probably right. The slower you fly, the less rudder response you get. The thing I love about my Skeeter is that it speeds up really well, but it also flys slow. But when I slow it down I don't expect very instantaneous turns out of it. Hard rudder, at a speed just safely above stall, yields kind of an ungainly yaw followed by a slow change in direction.

Try retrimming for a faster flying speed than you've been using. Add a few clicks of down trim (and don't allow yourself to compensate back into that slow flight mode by holding up elevator while flying -- it's tempting to do when you're adjusting to a new flight envelope.) I'll bet you discover you don't really give up much hang time and the ship comes into its own.

Bill

[BMatthews]

Didn't read all the posts but a couple of things stand out to me. First ensure that the tips have some washout in them. That helps a lot to reduce the tip stalling. Second it often doesn't pay to try to fly the model TOO slow. With flight on the ragged edge of the stall you also get a lot of drag. It's better to fly a smidge faster like a couple of mph so the wing is in a more effecient point in the performance range.

To add to the problem I have had models that do not like to respond crisply to the rudder when flown too slowly like near the stall. This may be your model's issue as well. Again the key is to keep it flying a little faster than this bad response speed.

Mostly it's about getting used to it again. Especially in tight turns learning to fly it efficiently.

I find that while speed regulation is a big part of it that it is hard to see the speed. A trick I use is to sort of time how many fuselage lengths of forward movement I have in any given time unit (it's subjective and a feel thing but hopefully you get the idea). Doing this fuselage lengths per second or other time unit lets you judge the speed at any distance because you're just using the fuselage length as your guide.

In the end though it's all about practice. Get more of it and the issues will seem more minor.

[schrederman]

Be careful about doing too much rudder throw. More than 30 degrees is just drag and the entire surface may stall... at which point it becomes a large spoiler...

Jack

[schrederman]

Hoss...

All my handlaunch stuff was about 10 miles north of Galveston Bay... pretty swampy... Sorry to take your excuses away, but...

Jack

[lincoln]

It's a polyhedral glider. If you want to turn faster, you have to fly faster, at least until you get banked. And it probably doesn't pay to fly QUITE as slow as you can. I wouldn't worry about washout too much, those tips are pretty wide. I stretched the tips on mine with a final tapered section and it still had nice handling.

How much does your glider weigh? I bet with that airfoil going below 10 oz or so isn't worth it.

When you get a Skeeter up high it's a lot like flying something larger, except that it's harder to see.

[Hossfly72]

I think I've figured it out. I have been flying too slow. And I also had more washout in the tips but I took it out and now there's just not enough. I'm also flying with an extreme rear CG, but that's where I used to fly it years ago. Had a minor mishap today and hit a light pole. Luckily, I was floating like a butterfly and all it did was spin down. Too bad there was a fence at the bottom!! Just knocked off the tail though. It's fixed now. I haven't weighed it yet, but I think it is right around 9.5 or 10 ounces. I blame it on modern radio gear. My building skills aren't that good anymore.
Here's what it would do today though. As I was circling in a (very) small thermal, I could make 3 or 4 turns and then it would just drop a the inside wing and nose dive about 10 or 15 feet straight down. Was I just yanking too hard on the rudder stick and stalled it out? I wish I had added just a bit more dihedral. I think it would perform a lot better with just that final touch.
Working on another plane now. I'm using the Skeeter as a start but it won't look anything like one when I'm done. I'm having a great time glueing and carving and sanding. I had forgotten how relaxing this hobby was. Thanks for all the tips folks!

Hoss
The eternal student

[kwmtrubrit]

I think I've figured it out. I have been flying too slow. And I also had more washout in the tips but I took it out and now there's just not enough. I'm also flying with an extreme rear CG, but that's where I used to fly it years ago. Had a minor mishap today and hit a light pole. Luckily, I was floating like a butterfly and all it did was spin down. Too bad there was a fence at the bottom!! Just knocked off the tail though. It's fixed now. I haven't weighed it yet, but I think it is right around 9.5 or 10 ounces. I blame it on modern radio gear. My building skills aren't that good anymore.
Here's what it would do today though. As I was circling in a (very) small thermal, I could make 3 or 4 turns and then it would just drop a the inside wing and nose dive about 10 or 15 feet straight down. Was I just yanking too hard on the rudder stick and stalled it out? I wish I had added just a bit more dihedral. I think it would perform a lot better with just that final touch.
Working on another plane now. I'm using the Skeeter as a start but it won't look anything like one when I'm done. I'm having a great time glueing and carving and sanding. I had forgotten how relaxing this hobby was. Thanks for all the tips folks!

Hoss
The eternal student

"Hoss,"

You answered part of your problem dropping a wing. You need to put some washout back in, its tip stalling. CALL JOE!!

[BMatthews]

Hey, if it was easy everyone would be a star:D Overall it sounds like you're just a little rusty and need to work out the kinks. Get a few more flights in and it'll be like you never stopped.

Every spring when I start up flying again I keep it in closer for the first day and watch my landing approaches a lot more until I got my "Ying" back in synch with my "Yang".

[Hossfly72]

Rust, lack of washout and not enough altitude.


result? Highstart ordered, towhook added to plane and more washout put back in. I'm gonna get it flying good and then stop changing things so I can get used to it.

[kentuckyglider]

I started with a Skeeter, and after I moved on to a Gentle Lady, I realized the Skeeter is a bit quirky. I had problems with both straight stalls and tip stalls. Can't say that I had much trouble turning it, though.

KG

[BMatthews]

I somehow missed the Skeeter bit. I have one and yeah, it's a bit prone to tip stalls. Put the washout back in.

I actually ended up making a new wing for mine. A hair more span and chord and it flies a lot nicer.

[Hossfly72]

Got it dialed in and flying great. I got the chance to re-test it today. From here on out, I aint touchin' nuthin!!!! Added washout back to it and did some minor repair work to a hole or two in the wing covering. Somebody touched on the key to the Skeeter though. In lift at altitude it flies like a much larger (ie- better) plane. Managed to get a little lift today and that's why I'll continue to love this little old, outdated lady!!

On the other hand, I do have a scratch built fuselage just about done and I will be making a wing and tailfeathers for it next weekend. It'll be a touch lighter, different airfoil and dihedral instead of polyhedral. I'm also going for tip launch capability instead of javelin. My shoulder hurts!