PETER BRUCE - Eastchurch Gap Posted October 8, 2012 Share Posted October 8, 2012 Part Two will follow soon. Quote Link to comment Share on other sites More sharing options...
David Davis Posted October 8, 2012 Share Posted October 8, 2012 ...and once you've tried it on a windy day, can you try it in a Fokker Triplane! Quote Link to comment Share on other sites More sharing options...
GrahamC Posted October 8, 2012 Share Posted October 8, 2012 Very interesting.... What about a roll? That would be interesting to see. Quote Link to comment Share on other sites More sharing options...
BB Posted October 8, 2012 Share Posted October 8, 2012 A Heli pilot at my club recently took up FW and after passing his 'A' Cert. Then fitted a 3 axis gyro to his .55 OS powered ARTF Wot 4. He flew it in a 20mph wind. Switching the gyro off and on the difference was really noticable. The Wotty bounced around in the changing air current regardless; But when the gyro was on, the flight lines were very smooth. The other Heli guys said it was cheating BB Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted October 8, 2012 Share Posted October 8, 2012 On my Baronette I have set it up for heading hold on a switch. With heading hold it will track straighter on take-off and landing, but obviously needs switching out once the wheels are off the ground. Even in rate mode it has a marked effect on normal flying, causing the tail to drag in turns as it tries to oppose the turn - you can see what happens in the video with opposite rudder coming in as the model turns. I really should dig it out and try using rate instead of HH for ground movements. Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 8, 2012 Share Posted October 8, 2012 Hi Bob, That was one of the things I was thinking - if using ailerons to turn will it not compensate the oposite way with rudder - would mixing in some rudder with ailerons calm this down as it will be getting an input and possibly ignore the turn? Cheers P Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted October 8, 2012 Share Posted October 8, 2012 The gyro will only keep the tail straight when there is no input to the rudder stick, using the throttle (assuming mode 2) will cause small movements naturally to the rudder anyhow so unless you do not touch the rudder / throttle at all would be best for test the gyro. You don't have to turn it on and off, normal rudder operation should prevail if the pilot wanted to use the rudder. Using the ailerons only would cause some interaction as the rudder would be moved by the gyro so mixing would help. Edited By Delta Whiskey on 08/10/2012 10:05:14 Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 8, 2012 Share Posted October 8, 2012 DW - thats kinda what I was thinking - would the gyro be tricked into thinking there was wind interferance from the turn due to the ailerons. When using gyros on a heli for example it wont encounter this problem as wind/engine tork is the only thing it has to combat. Cheers P Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted October 8, 2012 Author Share Posted October 8, 2012 Hi all thanks for all the comments so far as it gets the grey matter working - most comments mentioned here are correct from what I have observed however there is a side of this to consider some may miss. Any input you make on the Tx stick is directly proportional to the feedback you get back from your eyes. - So if the rudder "fights your turn" from the offset of your stick command you automatically feed in more Tx input to compensate for what your eyes see and your brain requires ... I hope that makes sense - Its just a bit more to think about. For my part I used to fly scale heli's and I always flew the tail because I never had a heading hold gyro - that's the reason I used a cheap gyro for this test - to keep it simple. The gyro was wired straight into the Rx and the other lead from the gyro went to the rudder servo - simple - the gyro gain was set to "mid range". I have often looked at tail draggers and noted the awful problems on take-off and landings which often occur (mine were my main concern) - on take off a blade of grass holding back a wheel for a moment longer before the model rolls could cause the take off run to skew off course and go wrong - like the wing beat of a butterfly compounded up and ending up as a hurricane... Anyway enough from me and I look forward to making the next video and see how it works in fair winds - I will even try cross wind take offs / landings. Regards Peter Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted October 8, 2012 Share Posted October 8, 2012 Posted by Phill Emerson on 08/10/2012 10:33:03: DW - thats kinda what I was thinking - would the gyro be tricked into thinking there was wind interferance from the turn due to the ailerons. When using gyros on a heli for example it wont encounter this problem as wind/engine tork is the only thing it has to combat. Cheers P Not true on a heli with a heading hold Gyro you have to co-ordinate aileron (bank) and rudder in a turn or the gyro will try and turn the tail (rudder) in the opposite diection and it will then just fly sideways into the ground. With a rate gyro you can do aileron turns only on a heli as per fixed wing. So if you are planning on using a heli gyro in a fixed wing then the following would apply - Rate gyro, plane will track round on an aileron turn - Heading Hold Gyro - needs co-ordinated aileron and rudder in a banked turn Quote Link to comment Share on other sites More sharing options...
Pete B Posted October 8, 2012 Share Posted October 8, 2012 Phill and DW are both correct. if you use aileron and elevator only for turns, the rudder will sense the change and keep trying to correct its path through the air. As you say, Peter, the more ail/ele you use, the more the rudder is corrected, thus exaggerating the tail-down attitude in the turn. The only way to deal with this is to use rudder to balance the turn, either as a stick command or by coupling the aileron and rudder. I have CAR on a switch so I can use it when I'm feeling lazy...... There's plenty more discussion on the 3-axis gyros going on in threads here and here. Pete ps Just seen Frank's post, which, ignoring the HH aspect, seems to be the opposite of what I've said... I understand the flight path concept in the heli with rate mode but in the fixed-wing, the tail will tend to drop in an ail/ele turn. Let's consider a turn to the right. The gyro will sense the tail moving from left to right as it drops and will apply left rudder to correct the movement, thus increasing the downward movement of the tail. This quite clearly happens with my 3-axis gyros in flight. An ail/ele turn exhibits a deep drop of the tail. If I co-ordinate the rudder with a right stick command (or with CAR) the tail balances out and follows the turn. Having said, I'm aware of Frank's experience and I am hesitant about contradicting him! Edited By Pete B on 08/10/2012 11:34:44 Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted October 8, 2012 Author Share Posted October 8, 2012 Thanks for informing me of the other site (see link from Pete B above) I had no idea this was going on. Its very interesting how sophisticated electronics are getting and the linked site shows this very clearly indeed however my approach was to "keep it very simple" and see the results which could be achieved with clear video coverage showing the results and with minimum cash outlay and effort. It is worth following the other site because this is truly "cutting edge" and mine is a bit "old hat" - I will still do the video and post it here to conclude the issue of this post for all who are interested. Regards Peter Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted October 8, 2012 Share Posted October 8, 2012 Interesting stuff - as I learnt to fly helis first, I naturally use the rudder on fixed wings too so testing a gyro in one should just be like flying a heli in a circuit, might get around to trying it one day in a cheap model ! Quote Link to comment Share on other sites More sharing options...
fly boy3 Posted October 8, 2012 Share Posted October 8, 2012 Hi Peter, said this before, but I always enjoy the blogs and videos from the Eastchurch Gap club. always entertaining and informative. Keep em coming Peter and thanks again. Cheers Edited By fly boy3 on 08/10/2012 12:31:12 Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted October 8, 2012 Share Posted October 8, 2012 Posted by Pete B on 08/10/2012 11:13:09: Having said, I'm aware of Frank's experience and I am hesitant about contradicting him! Edited By Pete B on 08/10/2012 11:34:44 Pete, I haven't tried any Gyros in my fixed wing so my experience with Gyros is all with helis. But a rate gyro just counteracts any uncommanded yaw, if the aircraft bank and turn are matched then the gyro shouldn't be seeing any uncommanded yaw so won't by trying to conteract this, but of course every plane is different so there maybe some unwanted effects. A heading hold gyro though will try and hold the heading and will hence use the rudder to try and adjust the heading unless otherwise instructed. The above has kindled my curiousity and I'm going to fit an old rate gyro into one of my planes just so I can check out the effects, I've also got one of the 3 axis stablisers winging its way to me at the moment. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted October 8, 2012 Share Posted October 8, 2012 I can only say that flying with gyro on a rate setting it was a pig to fly needing coordinated rudder with aileron to overcome the gyro. As I only wanted it to reduce the ground-looping, putting it on a switch suited me. Flying on HH was amusing to say the least. Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 8, 2012 Share Posted October 8, 2012 I am considering fitting one to my Velox to help with knife edge etc. Watching this and the other thread with the 3 axis unit with interest. P Quote Link to comment Share on other sites More sharing options...
Pete B Posted October 8, 2012 Share Posted October 8, 2012 Posted by Bob Cotsford on 08/10/2012 13:15:33: Flying on HH was amusing to say the least. You're not wrong, Bob! I'll continue to report my finding in the 3-axis thread, but my Eagle A3 Pro gyro gives both rate and HH options. The rate is fine but on HH, you've got to think about lots of things at once...... Once you have everything set up correctly - and having the model perfectly trimmed is essential - it's interesting to set the model off on a heading with HH switched in, take your fingers off the sticks and just watch it make its way unerringly to where you pointed it! I've seen videos of the shockie boys prop-standing with a HH setting but my models are not suitable for that - nor is my ability! The best I've achieved is to steer a course, pull in a bit of up elevator and then neutralise it. The model continues climbing, hands off - wondrous to see.......... Pete Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted October 8, 2012 Author Share Posted October 8, 2012 After I landed the plane from making the video the first question which came up in conversation was "can I take my test with one"... Wonder what the answer would be in ten years time - the march of technology goes on... Quote Link to comment Share on other sites More sharing options...
Pete B Posted October 8, 2012 Share Posted October 8, 2012 Posted by Frank Skilbeck on 08/10/2012 13:12:24: But a rate gyro just counteracts any uncommanded yaw, if the aircraft bank and turn are matched then the gyro shouldn't be seeing any uncommanded yaw so won't by trying to conteract this, but of course every plane is different so there maybe some unwanted effects. I think I see what you mean, Frank. The two conditions that will affect this will be the amount of yaw induced by the turn and the amount of gain set. A constant rate turn should cause only a marginal reaction by the gyro, probably not enough to be noticed from the ground - and that reaction will depend on the amount of gain. Peter, I can only say that, in my experience, the 3-axis gyro hasn't made me a better flier but, when I want it for, say, scale-like flight, it has made the experience more enjoyable. I wouldn't be surprised if there is a club-size ARTF available with a 3-axis gyro in the near future (micro AX3 types excepted). I don't think they are permitted for the BMFA tests - and rightly so! However, as you say, who's to know in the future? Pete Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted October 10, 2012 Author Share Posted October 10, 2012 So many questions from so many but the answer for you is to try it and see - wont make you a better pilot but it could help you in some instances with some planes - Seen any heli pilots without a tail gyro of late? Remember this project was started as a bit of "fun / interest" with the idea of keeping it very simple . (No need to be a qualified electrician to wire it). This is the final video I promised you which was made in winds from 10 to 16 MPH so have a look and see for yourself as the final choice has to yours and with your model. So are you going to give it a try - let us all know... Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted October 10, 2012 Author Share Posted October 10, 2012 I bet someone here will raise this so I will say now - I was beating off Mosquitos... So before I sign off here - the Tx was in my hand so it was never out of reach. I do not normal wave at passing model planes - not gone that mad yet - perhaps next year... Regards to all - Peter. Quote Link to comment Share on other sites More sharing options...
Dave Bran Posted October 10, 2012 Share Posted October 10, 2012 Posted by Pete B on 08/10/2012 11:13:09: Phill and DW are both correct. if you use aileron and elevator only for turns, the rudder will sense the change and keep trying to correct its path through the air. As you say, Peter, the more ail/ele you use, the more the rudder is corrected, thus exaggerating the tail-down attitude in the turn. The only way to deal with this is to use rudder to balance the turn, either as a stick command or by coupling the aileron and rudder. I have CAR on a switch so I can use it when I'm feeling lazy...... There's plenty more discussion on the 3-axis gyros going on in threads here and here. Pete ps Just seen Frank's post, which, ignoring the HH aspect, seems to be the opposite of what I've said... I understand the flight path concept in the heli with rate mode but in the fixed-wing, the tail will tend to drop in an ail/ele turn. Let's consider a turn to the right. The gyro will sense the tail moving from left to right as it drops and will apply left rudder to correct the movement, thus increasing the downward movement of the tail. This quite clearly happens with my 3-axis gyros in flight. An ail/ele turn exhibits a deep drop of the tail. If I co-ordinate the rudder with a right stick command (or with CAR) the tail balances out and follows the turn. Having said, I'm aware of Frank's experience and I am hesitant about contradicting him! Edited By Pete B on 08/10/2012 11:34:44 Sorry, but ............... not my experience at all !!!! (40 plus years fixed wing, five years rotary and have four planes with 3 axis gyros, the first fitted several months ago and flown lots since, along with unfitted ones and switched in/out ones). This reads like you are locked into a corrupted form of heading hold! I get no interaction of aileron/elevator into yaw with gyro that isn't there without, and even that is reduced ...................other than that, each axis gyro works as it should, for that surfaces effect alone, without unwanted interaction. Something rotten in the state of Denmark, methinks.................... BTW - they have markedly increased the usable wind range of every plane I have fitted them to, and make slope gliders much easier in bad rotor landing and launching zones. They do not take the skill out of it, they just widen the scope for lunacy!!! Quote Link to comment Share on other sites More sharing options...
Dave Bran Posted October 10, 2012 Share Posted October 10, 2012 Some of the effect you have with rudder only gyro is possibly as the Cougar tends to have relatively poor rudder control anyway, being inherently heavily roll coupled?? Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted October 10, 2012 Share Posted October 10, 2012 Just to add remember you need to let a gyro initialise, a few seconds after power on is normally enough with no movement of the model or stick input - good luck all ! As part of my heli startup routine after initilising and before starting the engine, I always move the tail to ensure gyro is working correctly. Quote Link to comment Share on other sites More sharing options...
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