Advice for take off of a tail dragger with steering wheel

[S55]

I put a steering wheel on my tail dragger and still have trouble to keep it straight on the ground. As it gains some speed it will start to turn right or left (most of the time it was left). Asking around, I was told it is common on tail draggers with or without steering wheel because at enough speed, the tail will lift even slightly and then you loose control.

The plane flies, if I manage somehow to get it to speed it will take off and fly, but most of the time I will be out of the run way before that.

How do you manage these things?

Thank you,
S55

[BEC]

Timely use of the rudder!

Depending generally on the main gear placement, some planes just love to ground loop. For them the only real solution is LOTS of power so the takeoff is quick. What plane is it? How is it powered?

[CoastalFlyer]

Since many tails will lift quickly I apply lot's of power, which (depending on the plane) gives the rudder some control.
Some planes are easier than others....

[pburress]

Turn your main wheels so they are pointed in just a little. This will help a lot.

Move or bend the main wheels forward.

Until it builds up a little speed, use up elevator to push the tail wheel down and have more positive (corrected) rudder control. As it builds up speed ease off the up elevator so you don't take off too soon.

[TooTall]

Yep...add a little tow-in on the main landing gear...it will help to track alot straighter on the ground....tt

[S55]

My front landing gear is as the top drawing and I thought the problem is caused by the arms being too flimsy, so I modified it as shown on the bottom by adding a carbon fiber shaft to keep the wheels in perfect alignment. I have not tried it since, too much wind.

Thanks for the very quick answers, it seems like you were waiting for this to come.

S55

[pburress]

S55, that may do the trick for you, if indeed your LG was flexing on the takeoff run!

[Mark Wood]

I agree with pburress and TooTall. It's a matter of "Been there, done that" as I fly taildraggers exclusively. You'll be surprised how much the toe-in helps ground handling. But, when all else fails...

HIT IT!!

mw

[TooTall]

it may not be clear in the pic, but the axle part of the landing gear is 'tweaked' toward the center line of the fuse....tt

[Rod]

I agree with the comments about toe-in for the wheels. On the faster type of models I just power on and take off real fast. On slower models, scale types etc. I hold a lot of up elevator untill the model is close to take off speed, then realease the up elevator and the rudder is sufficient to hold the models direction till take off. It is a delicate balance thogh, hold up elevator too long and you can pull the model into a full stall postion. At this point it is advisable to have a little excess power, and apply down elevator to flatten out the take off.

[S55]

Just to avoid confusion, which setup is the good one, left or right?
Thanks,
S55

[Artemetra]

Saturday I flew my SS and Christen Eagle. The Eagle has tons of power and ROG's in about 1.5 feet, but I can't taxi around worth diddly. However, it lands nicely, just starts to ground loop when it slows down. I'll try the toe-in.

The Slow Stick tracks straight, but it's a long plane and is "flying" even when it's taxiing. Has that silly wobbly wire/wheel on the back, too. I put 2" diameter wheels on the front after the stock 3.75" (or whatever those huge ones are that come with it) broke. Seems to work fine.

The Micro Whizz I had wouldn't taxi worth anything, but then it wouldn't fly anyway, so it needs more power as well. It's not a fun plane to hand launch, either, with a stick fuse.

[Artemetra]

Just to avoid confusion, which setup is the good one, left or right.
Thanks,
S55

Toe-in is the left drawing, but by the looks of those wheels, you'll never get off the ground due to weight. :D

[new2rc]

Hi S55

I know where your coming from. My son and I are first time pilots on a Superstar EP. It came with a skid which was impossible to control. I made a steer able tail wheel for it and put lots of "toe in" with some caster on the main gear. It can still be a handful for my untrained thumbs :rolleyes:, but my son makes it look easy and he is 11 with fewer flights than I :eek:. Even with right thrust built in to the motor mounting, she still will torque left pretty hard on full power even with the orig. T601 and prop. Christopher can anticipate with right rudder instinctively ;). Dad though is more of a West on N - S runway kind of guy :D. I may try a Sullivan tailwheel which has some caster and is sprung to maybe give a more forgiving response to rudder input.
Good luck and continued flying success!

John and Christo

[PGR]

The best way I've found to prevent takeoff roll problems is get airborne. That doesn't necessarily mean I start climbing right away but I like to quit steering and start flying ASAP. Most of my planes will blow the tail wheel off the ground before the plane really starts moving anyway so the rudder has a lot more authority than my dinky tail wheels.

I used to slowly ease on the throttle but found that doing so caused me a lot more grief than just going for it.

Pete

[Martin Hunter]

Ditto.

"Punch it, Chewy!"

Martin

[jbird]

I haven't had a model with trike gear, all have been tail draggers. Punch it works if the prop can move enough air over the rudder at slow speed. Higher pitched props will be "cavitating" at first and not move a whole lot of air until the plane gets moving. Sometimes it's necessary to have up elevator for the first couple of seconds to keep the tail wheel on the ground until speed (air over the rudder is up).

Also for ground handling ie taxing with wind. Don't forget to "fly the airplane" on the ground. This includes the ailerons with any cross wind component. When taxing into the wind, up elevator. When taxing with the wind - down elevator to keep the tail planted so steerable tail wheel can do you some good.

Jim

[abenn]

All my models are tail draggers, and I personally don't notice any difference between skid or fixed tailwheel or steerable tailwheel. The key to getting them all off the ground neatly is, as many people above have said, to initially hold the tail down by pulling full up elevator, then when there's reasonable forward speed, allow the tail to lift. But most important is to get used to using the rudder to steer it on the ground and resist the temptation to heave it off the ground as quickly as possible. Many modellers (myself included) are rather ham-fisted with the rudder control due to lack of practice, so practice is what is needed.

[S55]

I like the idea of using up elevator and understand it might be tricky. Will try it as soon as weather permits.
The toe in modification is difficult as I just changed the gear as described earlier and would like to keep it like that because it has some nice elastic bands to sweeten landing hits.
S55

[Martin Hunter]

The only caution about using up elevator is that with a high powered airplane, that can result in a very fast takeoff and abrupt nose-up. Most any of my planes would be off the ground just as quick with up elevator and into the first part of a loop. However, up elevator can work great for a slower takeoff or a lower powered plane.

Martin

[E-Challenged]

The wire leg for the tail wheel can be lengthend a little so that the plane sits at a less of an angle to the ground to make ROG's easier with a tail dragger. The main gear axles should line up with the wing leading edge or just behind it to prevent tip-overs/prop strikes. Wheels should point inward slightly. When taking off, hold up elevator and right rudder, apply throttle gradually as you get rolling then slowly release elevator to neutral to let tail rise while adjusting rudder as needed to keep the plane heading straight. As speed builds, airstream on tail feathers stabilizes plane so that it will fly off the ground with only slight right rudder. Ailerons only become effective as speed builds, rudder controls right / left heading during take-off run. When you get some altitude, release right rudder and fly normally.

Ailerons lose effectiveness at low speeds such as when landing, use rudder to control right/left heading before touch down. If you can take the wing off, you could practice using throttle, rudder and elevator without worrying about liftoff. The rudder is also helps make smooth turns in coordination withthe ailerons. Practice hangar flying using rudder and throttle stick with aileron and elevator stick until it becomes natural to you. When you learn this you will feel superior to trike gear flyers and hand launchers. :D

[Jimbo45cn]

Full power, watch for the left crank. Away you go! Jim

[tommy321]

Having a slightly higher tailwheel can help. The worst part of the take off roll is when the tail comes up. The propellor disk gets tilted and due to precession, it wants to yaw the plane to the left. Hence needing the right rudder on take-off.

The best solution is practice, and keep that left thumb working (assuming mode 1). On calm days, one of my favourite things is doing touch and goes without letting the tailwheel touch at all with my Jitterbug. It takes lots of finesse, practice, and constant rudder work. The other thing I like to do is use every foot of my clubs 200ft paved runway for takeoff. The tail comes up in about the first 2 feet and then I just let it taxi SLOWLY down the entire runway on two wheels and then at the end I give it another breath of power and I'm off... It's kinda comical looking because if you've seen any movies of a Jitterbug, it can typically get off the ground in 2 feet if you want :P

Anyways, just practice practice practice. Tail draggers certainly don't loose control when the tail comes up. Often, that's when you have the most steering authority.

Tom

[boomerace]

What radio are you using and on what channel and freqency for flying. I wasn't aware a air legal Radio was available with a steering wheel. :confused:
boomer
www.boomerseflight.com

[S55]

Steering wheel and rudder are driven by the same servo, therefore I cannot do the right rudder trick on the ground. The wing comes off and practicing without it on the ground sounds like a good idea.
S55

[boomerace]

Steering wheel and rudder are driven by the same servo, therefore I cannot do the right rudder trick on the ground. The wing comes off and practicing without it on the ground sounds like a good idea.
S55
That clears things up as you are calling the wheel on your rudder a "steering wheel".
boomer
www.boomerseflight.com

[S55]

OK, I'm open to learning. How should I call a wheel that is steerable?
S55

[TooTall]

steerable tail wheel...not so a "steering wheel" as known as on rc car tx's...or a steerable nose gear on a trike gear...fyi...tt

[PGR]

OK, I'm open to learning. How should I call a wheel that is steerable?Ballast ;)

Pete

[tommy321]

I don't understand why you say can't do the right rudder trick on the ground. If the tailwheel is steerable, it's always controlled by the rudder servo as far as I know. You should be able to steer on the ground just fine using the rudder and attached tailwheel.

Basically, they just work together. If you happen to be moving slowly, there won't be much wind over your rudder and the tailwheel will be doing all of your steering.
Now start moving faster, but with the tailwheel still in contact on the ground. There's air going over the rudder now, so deflecting it will provide steering control. But you're tailwheel is still on the ground, so it will ALSO provide steering control. But since they're working together, you just move the left stick until the airplane is doing what you want (turning, going straight, whatever).
Now, going even FASTER, your tail will lift up. Now your tailwheel isn't touching the ground anymore, but there's enough air going over your rudder that it should be able to provide all the steering you need. Again, you still just move the left stick until the airplane is doing what you want.

The catch is that at different speeds, you'll have different amounts of steering effectiveness because you're transitioning from tailwheel-only control to tailwheel+rudder control to rudder-only control. Each phase of the take-off will need slightly different rudder stick inputs to keep the model straight. So, on a long, graceful (scale) take-off, your left stick will have to constantly make small corrections to keep the airplane straight.

Sounds tricky, and it is... it takes practice, but in the end it'll make you a better pilot. And it's a must if you fly at a field with a fixed runway and have to do crosswind takeoffs properly

Have fun,

Tom

[S55]

Tommy 321,
I was referring to the approach described by E-Challenged who said keep up elevator and right rudder at start. Well, if I do right rudder, the plane will also turn right, while I want it straight.
Having both rudder and wheel coupled, I can do what you said and will try my best this afternoon, it’s sunny and dry, and I hope the wind will be friendly too.
S55

[Old Man]

S55
Back in the late 1970's when you could taxi in and out of the pits, I struggled with the same thing you are struggling with right now. I could not taxi and struggled to take off without going off of the runway. After several people laughed at me for pushing my plane to the runway, one of the local hotdogs told me this. "Part of flying model planes, is knowing how to handle your plane on the ground. Not just flying." He then took the time to help me learn how to taxi.

Tommy 321 and everybody else are giving you great advise, practice, practice, practice. Watch what your plane is doing on the ground and use SUTTLE inputs to keep the plane on track. If you can remove the wing, remove it and drive the plane around like a car. looks silly but you can build up speed without taking off. The biggest thing is to watch what the plane is doing and use just enough input to keep it on track.

It will take lots of practice but I am sure you can master it, just keep trying.

[Phantom2plus2]

Great advice here. Should help anyone who is having trouble ROGing a taildragger.

Boomer..PGR.. you guys are killing me. Alittle well placed humor is always nice. Thanks guys.

David

[Vette]

Taildraggers by their very design are difficult to contol on the ground. I find one thing helps me is that I watch the first ground loops, most of the time it happens more one to one side than to the other at least on my planes. After a couple of times I am ready to feed in enough rudder correction before the plane gets completely out of control. You need to watch and be ready to correct as the plane starts moving. When the plane JUST starts to veer off feed in enough rudder to correct THEN be ready to correct the other way because that is where it is going to try to go because you over corrected the first time. It is just like making a mistake, it is easier to correct a small mistake before it gets to be a big mistake, same principle. You will find the shorter the fuse on the plane the worse it handles too.
There's a darn good reason you don't see many land vehicles with rear wheel steering, no high speed ones that I know of. If you ever get to drive a Towmotor/lift truck you will find they kind of like to ground loop too.

Joe

Oh I forgot that if you try running around without the wing, be careful, they go like skat and don't like to stop til they hit something. They also flip over real easy so don't turn very fast. Been there....

[S55]

Thank you all. I got home too late, it was almost dark. Maybe tomorrow or during the weekend.
S55

[tommy321]

The trick was said above, just use small control inputs on the rudder. If with no rudder the plane goes left, and with full rudder the plane goes right, there must be some place where the plane goes straight. You have to find this middle ground. It’s a moving target though. At the start of the roll you’ll need lots of rudder (because there’s no airflow over your tail). As the tail comes up you’ll need a bit to fight the gyroscopic precession of the propeller. By the time you’re ready to take off you’ll need almost none because you’re essentially flying at this point and I’m assuming you’re trimmed for level flight :P

Good luck. Flying a tailtragger is much more fun than tricycle IMHO. I’m reminded of the bumper sticker…. “REAL PILOTS FLY TAIL-DRAGGERS” ;)

[Berk]

I got a similar problem, I wish I could get away with using a skid, but I can't.

The height the skid gives me means that the elevator counterbalances could hit the grass with disastrous results!!

I need to fit a wheel to the skid to increase ground clearance, but if i leave it castoring will it give me problems??...

It's the wrong end of the model to add weight, especially as I have 2*9405 servos at the rear!!

Regards,

Steve

[willfly]

Left turn on ROG is a common problem with Tail draggers. Theory goes that, as the plane starts moving, headwind is not perpendicular to the propeller disk. Hence blade going down sees higher angle of attack and generates more thrust then other. Apparently tri cycle gear should not have this problem if it is aligned properly, but I have verified this theory by keeping tail higher on a dolly during take off.

How to manage left turns: Give full throttle, and up elevator as soon as tail lifts off.

[E-Challenged]

I have had a number of tail draggers with tailwheels hooked directly to the rudder as well as tailwheel linked to the rudder servo to get less throw on tail wheel than rudder. Either type works. You start your roll with up elevator and a little right rudder steering with the tailwheel, then release the elevator and tail will rise, now you change over to controlling plane's heading with the rudder alone making subtle movements and anticipating swing to the right or left as needed. You can give slight down elevator to keep the plane from lifting off until you have sufficient speed for safe take off and climb out. You will notice that you can release right rudder after you gain some altitude
and then your ailerons( if you have them) plus elevator become your primary turning controls. With ailerons, you can add rudder to help make turns more smoothly. I set up my transmitter to mix in a little rudder with ailerons when I hit a switch or do I it manually. Too bad that ARF parkflyer makers don't include instructions like these to help beginners get started.

[S55]

E-challenged and others,
All you say makes sense and it is nice you can apply these tips (especially use a bit of down elevator to prevent the plane take-off once the tail is up, but it has not enough speed yet), but for my unexperienced fingers I would need all this to happen in slow motion.
I will post results later today as it is sunny and I am currently charging twp packs in order to go outside.
S55

[zeuglodon]

Power. Most of our overpowered planes will be flying before you need to do much correction if you just give it full throttle and a little "up".

If you can't get it to take off straight under those circumstances, you probably have some thrust issues.

[BMatthews]

A lot of the turning during takeoffs is due to crosswinds acting on the model to try to steer it into the wind like a weathervane. If you know there's a cross wind on the runway or takeoff line then be ready on the rudder for the nose to try to point into the wind. Learning to add some rudder to hold the model straight is just part of being a tail dragger pilot. The toe in helps but it doesn't cure the problem. It's a challenge for sure! But that's part of the fun for me.

[S55]

I took the plane out yesterday and first tried some maneuvers in the school parking lot with the wing removed. I used up elevator and after gaining some speed I released it. The tail lifted and the plane continued to run on two wheels only. I tried little left and right corrections with the rudder and the plane responded. Too much correction resulted in a roll over. Well I thought I can do it, attached the wing and went on the baseball diamond on the nearby field.
Up elevator, full throttle, release the elevator, the plane takes off. All this with an almost straight run on bumpy dirt. I did it several times and it worked almost all the time. The landings were in the grass though and the plane used to roll over the nose, I never succeeded to bring it back on the dirt.
Then I got a problem with the gear pinion, but I will post it on the Power section.
Thanks for all the good advice.
S55

[mjws]

All that extra power is nice. Just pull back and crank it.

I'll admit to the occasional suprise when you've got the barndoor rates on for harrier landings, you punch it and are vertical to upside down before you can blink. :) Looks cool though.

I've got a couple planes with just brutal ground handling. Toe in helps a lot. So does good trimming and making sure everything is aligned right. After that it's all practice.

Mike

[Karl B²]

The height the skid gives me means that the elevator counterbalances could hit the grass with disastrous results!!
Maybe you need little wheels on the balance tabs. :)

I haven't had good luck with a freely castering tailwheel. While takeoffs may work okay, you might need wheels on the wingtips too for all the groundloops this will cause, especially when taxiing in any direction except into the wind.

[Haj 78]

The first think to check when tack off is go straight to wind direction.
If not the plan with or without tail wheel tends to turn to that wind blowing direction.
When on the run for take off with full power (if your engine is not too powered) try to take tail (and wheel) out of the ground as soon as possible, and steer only with rudder. Just down elevator till you have enough speed to take off and then up elevator and you are on your own on the air
Regarding Toe-in, (not to much) this is a better choice because this way landing gear is not forced aft and sideway. Besides when you take off usually one wing is with more lift (cause of wind direction) than the other so you have more load in one front wheel than the other, and you will have only two wells (0 or half – tail wheel) load on ground

[50+AirYears]

The landing gear placement on the fuse has some effect as well. The best ground handling I've had on taildraggers had the wheel axles either directly under the wing LE with the wing set parallel to the ground, or a small amount ahead of that point. Too far forward or back makes the plane squirrely. Too far back gives the plane a serious tendency to nose over, and if it's too far forward, you had better try your take-offs either directly into the wind, or sometimes directly with the wind, as I had to do with a couple SAM Old Timers.