Semi Retired Aviator

I have one of this type, and it doesn`t spin easily. I have to put in a lot of control to induce a spin, otherwise it just mushes down, wobbling a little as it goes. I agree with Red Wing; it flys rock solid, can fly very slow, and is hard to upset. In fact is flys a lot better than a couple of high wing trainers I`ve flown, as far as stability goes, and I think would make a better FIRST plane than a high wing trainer.

If it was a dud aileron servo/or wrong aileron input, surely the rudder would pull it back, assuming he let off the aileron input, and he had enough speed for the rudder to be effective. Lot of IF`s here.

Sounds like it may, and only may, have been wrong rudder input to correct when things started to go a little pear shaped.

It`s very difficult to remember exactly what you were doing with the sticks as your new model is headed south and about to return itself to a bunch of balsa and plywood sticks.

I`m no expert, have made every mistake there is to be made, and then some, and I`m only guessing.

Better start equipping our models with flight data recorders!!

forestroke

while the reversed aileron theory is good, I would suggest that this may be the first time for smoggyboy to be flying a 4 channel plane. if you don't make the plane square and it rolls without any input at neutral time, i would say that it is possible that no amount of rudder to right it. Remember that this is a low wing, low dihedral plane. You can't expect it to react to rudder inputs like a trainer.

so my 2 cents is that the model needed quite a bit of aileron trim to get it flying hands off. Because Smoggyboy used the rudder instead of the aileron and the fact that this is a low dihedral, low wing plane, means that the plane may have yawed but not rolled.

smoggyboy - you were turned on as well... hmmm... curious! lol!

typicalaimster

You know with the simulators out there it's not that hard to tech yourself. I made more progress flying the simulator for 2 months than I would have in a year with the real thing. The simulator is a nice post crash tool. You can set the plane up 'like' the one you are flying. You then put yourself in the situation that caused you to crash. From there you can figure out what caused what to happen.

--Scott

bruce88123

Again, if you gentlemen will refer to some of "Smoggy's" other threads, you will see that he apparently has been flying for a bit. I cannon explain why he is not speaking up for himself at this point however. Perhaps he is away from his computer.

Bruce []

rctrax

My main comment is that we do not have enough info to make a judgment call on this.Was he using right stick for rudder? Ailerons? He didn't say which stick he had hard over, which control was being used Rudder? airilons? If he was using ailerons the speed might have been too slow to make the ailerons efective.Too many things too consider to make a call as to the cause without more info

bruce88123

EXACTLY!!!!!!!!!

forestroke

AHHHHH.... it's "maiden flight WRITE off"! lol... didn't see that until now :-)

forestroke

I guess smoggyboy is on vacation. If he is in central China, then it is lunar new year (aka chinese new year) break for a week. Anyway, I checked his last airplane (from his crashed picture) and it looks like a three channel high wing electric. That would support my theory! buhahahaha....

Smoggyboy

hi gents, so sorry I have not had access to a computer for a few days. I hope you will still respond.
Can I take one scenario at a time,
The receiver was bought brand new for this plane as my other had had a bit of a rough life.
The rechargeable RX BAT was also new and checked.
Ailerons reversed. Definitely not the case. I checked pre and post flight. Besides I did not get time to use them. The rudder was still in the full left position when I retrieved the thr bits.
Stall, I can't think it was this, I used the full length of the available runway, approx fifty meters. The plane took off perfectly into a very gentle climb. It was carrying enough speed about twenty feet up to bury the engine, smashing the carb off, ripped through the right wing, separating the fuse into two half's and countless other bits and pieces.
Servo horns. All were fixed solid and working free
My TX Ariel was extended.
Getting help at the field is not possible , I am on my own.
I have gone over and over this in my mind and I would feel better if I knew it was pilot error, at least I would know the way forward.
I am getting another WM SS40 sent out to me, it's personal now, I have got to get this bird in the air.
I have decided to salvage what I can from the first one, tail, stableiser and I will shorten the wing a little and use the materials I cut off to repair the damage in the right wing. I will make a fuse and stick a little .28 in, I have sitting about and have some fun with it.

My thoughts at the moment are that.
I should have done a range check. I will have my gear down to the field to do this asap.
I am going to change my frequency. Out here its a bit strange, 27mhz, 40mhz,72mhz or 85mhz. I crashed using 72mhz so I will change.
The plane by the way went together really well and looked a bit retro very very nice ARF from World Models, not that I am an expert in any way, but I have to try again.

Thanks to you all, any further thoughts would be good, I feel it was radio gear, OR ME, OR MAYBE JUST ME, I don't know.

Just one last thought, I put a new servo on the rudder/nose wheel, 6.5kg Can't think of the number, but I remember it buzzing all the time when turned on. Would this cause interference ?

bruce88123

Is this the same plane I recall you having cg questions over in another thread? Could this have been a CG issue? Doubt the buzzing caused any interference, frequently means a slight bind in controls. A definite YES on the need for a range check, especially on a new plane. Didn't have time for ailerons? Was your other hand at lunch? If you got to 20 ft you had plenty of time to be fully on both sticks, if not upon takeoff. Practice this before next flight. Did you not say in another thread you had aileron and throttle on left stick? If so, how did you apply power w/o being ready for aileron? Not trying to pick on you, only trying to understand and help you not do this again.[] A clipped wing version of your plane will have a higher stall speed, how much higher depends on how much shorter. Less wing + less motor = more runway also.

Good luck,
Bruce

forestroke

I think that is your answer Smoggyboy, you've got to use the ailerons. You cannot expect a low-wing plane to right itself like a high-wing trainer. Therefore if your plane is not trimmed out properly it will roll and crash. It is very likely that the despite all the airplane's control surfaces being neutral, the airplane will roll right. Unlike a trainer which is self righting and generally larger dihedral, a low-wing plane may not respond to the left rudder in the same way. A low-wing trainer will yaw (turn) but may not roll as much. Full left rudder still may not be enough to compensate for wings that rolls right.

I would say this, in your next attempt, do NOT fiddle with the rudder. It is NOT the significant control surface to trim in a 4-channel plane. What you should have done is trimmed the elevator and ailerons first. While I do not condone flying without rudder, it is absolutely possible. Leave rudder trim last. In fact, if you trim the ailerons for level flight, you may never need to trim the rudder as long as you are not doing IMAC stuff.

I'm positive that if you don't have the SS40 trimmed out well, it will roll into its death regardless of your rudder input. I suggest you get some 4-channel high-wing trainer experience first before attempting another low-wing trainer flight. Learn how to use the ailerons!!! Good luck!

bruce88123

It only takes a slight misalignment of aileron trim to get past the point where the rudder can correct for it. On a plane like you had, once the airplane rotates and the nose wheel is in the air the primary roll control is the ailerons. The rudder then becomes secondary to compensate for yaw. The plane is not designed for rudder control as a primary function and you have found that out the hard way. On the first flight of ANY plane, you must be ready to instantly correct for any out of trim conditions and climb the plane to a safe altitude before attempting to adjust the trims. Just as in full size planes, when there is a problem- fly the plane first and figure out how to fix it when you have time. Too many people crash worrying about correcting small problems and forget to keep the plane in the air first.

DBCherry

My Feedback: (4)

As Fourstroke and Bruce have said, not touching the ailerons most likely caused the crash. With a low wing plane fully deploying left rudder may well 'cause' the plane to roll right.

Think of it like this, most of the rudder surface (if not all) is above the thrust line, (or center of the plane), when you apply full left rudder not only will it push the nose to the left, it will also be trying to push the right side of the plane down. You have to compensate for this by applying some left aileron.

On a high wing plane with significant dihedral, that dihedral compensates for the rolling induced by rudder.

As Bruce said, leave the rudder alone once the airplane is off the ground, and use rudder as your primary control for turning. Once the plane is at a safe altitude adjust your trims, then play with the rudder. I think you'll find that the affect it has on the plane is significantly different than a high wing plane.

Good luck with the next one.
Dennis-

bruce88123

dbcherry- need to edit last paragraph. you said to use rudder as primary roll control and I know you meant ailerons.

RedWing

My Feedback: (4)

I am in agreement with DBCherry, Fourstroke and Bruce.
I have this plane and giving it rudder will roll the plane. Once off the ground use your ailerons.
Get used to using them.
Also, make sure you are on with your CG.
My CG is right on and even a little back, it flys great.
Although you can get this plane to hop off the ground on takeoff, keep it on the ground and lift off slowly. Get it up, keep it straight, get some altitude then start your first turn. Remember, fly the plane, if you need to trim it don't sacrifice flying. You may only get to get a few adjustments on trim per fly by. That is ok, just keep flying and compensating if it is out of trim.
I know mine flew great, only a few clicks of aileron.

Bill

bruce88123

If you have ANYBODY with you, show them how to adjust the trims and have them make the adjustments while you fly. If you don't trust them, keep them away and take your time. SAFETY IN ALTITUDE. It gives you time to GLANCE away and adjust trims. Better yet, while you sit around watching TV at night practice adjusting trims without looking at them. Transmitter off of course. Like the Army teaches soldiers to assemble guns blindfolded or pilots to find switches in cockpits by touch at night. Fly with one hand and adjust with the other. Whatever works for YOU, find a way.[>:

forestroke

Bruce - that is great advice. I completely agree that you should try to have someone around to help you with trims. Particularly with maiden flights. Beginners should always heed that advice because there is NO WAY IN HELL you will be comfortable in releasing the sticks if your plane is rolling or diving. Even now when I maiden a plane I try to have someone next to me in case I need major help with trims. Sometimes you just need to have both fingers on the sticks.

I have an idea, though. Why not fly your plane but first trimming the elevator. I have never done this but it sounds like a good idea. Instead of using the elevator to take off, use the elevator trim first to get off the ground after achieving take off speed. Then you know that at least elevator is trimmed out so that it isn't going to dive when you take pressure off. The WORST is when your plane both dives and rolls. Then you have no hands to trim either one. You can finish take off with a little elevator pressure then focus your left hand on trimming the aileron (Mode 1).

Which reminds me, are you flying Mode 1 or Mode 2? I think there is some funny thing going on. You have successfully flown a 3-channel plane. Unless you flew on a single stick tx, you should already be familiar with using both sticks. If you fly Mode 1, which is generally the case in Asia (elevator and rudder on left), it would be very weird for you to be giving full rudder rather than full aileron. Generally speaking a 3 channel radio in asia will have elevator on the left and rudder on the right. Translated to 4 channel, those two inputs should be elevator and aileron. Did you have your rx wired differently? Mode 1: elevator and rudder on left stick, throttle and aileron on right stick.

Also, in terms of TX, I would recommend mechanical trims over digital ones for the beginner particularly the beginner builder. Mechanical trims are much easier to adjust for maiden flights.

Good luck!!! I wish I were in China to help you!!! I was in Luoyang (aka middle of China) for 6 months a few years ago. I might be in Shanghai in the near future. Whereabouts are you?

Smoggyboy

Thanks for all the tips and adnice. I am convinced now it was my fault. Pilot error.

BTW, The CG WAS Absolutely bang on the nail with an empty fuel tank.

My training aircraft was .15 size, 3 channel, but I converted the wing many months ago with very good results, to make it 4 channel. From that I made a .25 size 4 Function low wing plane out of bits and pieces from the carbon fibre plant I am Installation manager at. It flies well after a few initial hairy moments.
I now fully understand the dynamics of the crash. I have input the parameters into my G3 Flight sim with very similar results, although not resulting in a crash the plane behaved in a very similar manner to my SS40. I am very self critical, and I feel better that I know the problem was me, and not the way I assembled/set up the plane . My TX set up, there a thing. I seem to have fallen between the gap in the chairs, Not mode 1 or 2. RIGHT STICK-ELEVATOR/RUDDER, LEFT STICK-THROTTLE/AILERON. I am intending to have a little time away from actual flighting and spend some time on my G3 to get my fingers/brain co-ordinated better. I have the next three weeks or so before my new SS40 arrives and another week before she will be ready. This has been a hard lesson for me, but one I shall NOT forget. This is a very steep learning curve, but I feel I am close to getting it.

Thanks again Gents for all your time and effort in helping me, If I could, I would buy you all a beer.

forestroke; I should still be here if you can get accross. I am in BengBU, An-Hui province, its the poorest in China so not a lot to do.
Keep in touch and if you do get the chance we will get together.

bruce88123

forestroke-

Smoggy addressed the mode issue in another thread and I believe the consensus there finally came up with calling it "Mode 4". As he was totally self taught, he just set his planes up the way he liked. Perhaps he just started out with rud/elev on the right so when he added a function the only avail stick was on the left. Again, a hazard of self teaching and perhaps not reading the manuals that come with the planes and radios. Only Smoggy knows for sure. I don't think it is too late for him to change over to "Mode 2". Should be just a matter of moving servo plugs and checking direction of throws. Think about it for your next plane Smoggy, MOST of us sport fliers find it more intuitive to fly Mode 2. Most of those not flying Mode 2 use Mode 1. I won't get into the pro/con issues here, I'll leave that for others. Mode 2 is ail/elev on the right stick, just like holding the stick of a Piper Cub or P-51 between your legs. No, I'm not suggesting that you hold your transmitter between your legs. Be serious for a moment.

Bruce[

JohnBuckner

My Feedback: (1)

[quote]ORIGINAL: bruce88123

forestroke-

MOST of us sport fliers find it more intuitive to fly Mode 2. Most of those not flying Mode 2 use Mode 1.
Bruce[
[/quote


While possibly true in the US, this gentlemans home base is in the UK. where I beleve mode 1 is predominate. It would make much more sense to learn in whatever mode is preferred at your home base.

bruce88123

Tryin to say somethin John?

forestroke

the mode 1, mode 2 debate can go on forever! there is no real evidence to say one is really better than the other. i have flown mode 1 and 2 and find that i like mode 1 better. i don't find that one is more intuitive than the other. in any case, we should drop it!

the only thing that's important is the amount of support you'll be able to get flying mode 1 in the states or mode 2 everywhere else. you won't be able to teach students to fly or have other people help you maiden planes.

smoggyboy - if you will live in asia, fly mode 1... if you plan to spend most of your life in the states, fly mode 2. changing IS possible while it's still not instinctual. anyway, if you can make it out to hong kong, i'll see if i can hook you up with some people that fly. they might be able to give you a few lessons. i have an extra trainer cable that i can send if you plan to go. cheers!

JohnBuckner

My Feedback: (1)

I seem to have reached the limit of my communication skills if that does not 'say anything'.

Anyway fourestroke's post says it pretty well.

John


Edit spelling

bruce88123

This I understand. Your original post #45 just came up as a big black square on my computer for some reason. Wasn't trying to be "cute", there just wasn't anything there to read and still isn't. All is clear in post #48, thanks and I agree. Not sure he has a home base tho.

Bruce

Did anyone else see just a big black square on post #45? Or is it just my computer?

bubbagates

My Feedback: (32)

Bruce,

I think you computer is haunted [X(] I can read post 45 just fine

See if you can read it as a quote


[quote]ORIGINAL: JohnBuckner