expo for beginners yes or no ?

[AVC]

I don;t see why a beginner should not use expos. Beginners have normally a bit of "shaking fingers", and in addition they have no clue how sensitive the stick movement could be. Exponentials will help on this first stages so that the beginner is focused on flying (one step at a time...)

Recently, I took my children for their first session. It was funny that every time that I passed the control to them, the model began to climb and bank to the left (they only had control on ail and elev), and I had to take back the control. They both said that they weren't doing any input, so I landed the model and tried several times to pass the control in neutral sticks, to check if the trim was incorrectly setup, and the controls didn't move at all. I added 25% expo to channels 1 and 2, and the problem disappeared. This allowed them to fly for longer, enjoying the experience and learning a lot!.

So in my opinion, expo for beginners, of course! (and for everyone else )

Edited By AVC on 03/07/2018 10:30:00

Edited By AVC on 03/07/2018 10:30:18

[David Davis]

Posted by Jon - Laser Engines on 03/07/2018 09:14:11:

... Most trainers are really benign.

I think that's true if you can already fly! I really don't have a dog in this fight. I'm a real technophobe and did not use expo in any of my models for years. Even in pre-expo days I used to have my models set up pretty sharp and told my pupils that if you can fly this, set up as it is, you can fly anything.

However, I introduced 25% expo on one of my models and the scales fell from my eyes, it was much easier to fly and I used it on several more.

That said I am currently instructing on a Boomerang 2 powered by an Enya 45. My trainee pilot is a 61 year-old who is making steady progress. He is making the usual beginner's mistakes of using controls which are too coarse and not balancing the ailerons with the elevator in the turns but he's getting there. I still have to take control back a few times on each flight but he's making steady progress. Imagine my surpise when this thread prompted me to inspect the settings on my transmitter. I found that I was using no expo at all! I think I'll keep it that way at least for the time being.

He's rather better on my Junior 60 or Radian, three channel models which are more automatically stable. This is my favoured route with most beginners over the age of forty-five ish. I know it's more guided free-flight than radio control but just having control of something which flies sedately through the sky builds confidence before we go on to ailerons. We had a splendid long flight with the Junior 60 on Sunday morning gliding about in the thermals for over twenty minutes.

[MattyB]

IMO there's nothing wrong with a small amount of expo (say 20-30% max) for a nervous newbie, especially if you are starting with an aileron equipped model - we've all taught people who over-control in the early flights. I learnt with expo and it's not done me any harm.

Jon is right though that if it's a decent trainer and the CG and control movements are set correctly there shouldn't be a need for it, especially if the first flights are on a buddy lead. The secret is to ensure initial setup is overseen by an experienced pilot so the CG is in a safe starting point and the controls are near enough harmonised from the moment the wheels leave the ground; this gives the newcomer the best chance of success without needing expo.

Edited By MattyB on 03/07/2018 10:55:39

[simon barr]

Its a hobby, guys... If you feel the need to use expo for either training or general flight, then use it.

Why struggle, even with a well set-up model, when all the gizmos are there to help us?

There is no right or wrong, just do whatever you want to do and enjoy!

[john stones 1 - Moderator]

Of course it is a hobby, set a learners model up to suit them, don't let your own ego nor sense of right influence how they should set up, you're teaching, don't dictate, ask their opinion.

[Kevin 216]

Posted by Jon - Laser Engines on 03/07/2018 08:53:56:

Posted by Kevin 216 on 03/07/2018 08:33:31:

I learned to fly recently and did not use expo on aileron and elevator. However, I found I had a tendency, when advancing the throttle for take-off to feed in a little rudder input. 30% expo on the rudder mitigated the problem and my small stick errors were damped out - result straight take-offs. I still fly in this configuration zero expo on aileron & elevator, 30% on rudder.

As for rates I set them and usually maiden my model on low rates once satisfied all is well I use full rates.

With all respect to Kevin (this is not a personal criticism) this is exactly why you shouldnt use expo when learning. Instead of learning to move the throttle accurately the error is being masked by the expo and by his own admission that state is set to continue, most likely for the rest of the time he is a model pilot.

Its a far better bet to learn to move the sticks accurately in the first place. All of my students do the same with the throttle/rudder interaction so you arent alone in that, but within a handfull of takeoffs and some dedicated rudder training they soon kick the habit.

No offence taken Jon, couldn't agree more with you, I have been taught to fly with the rudder and use it when needed in flight and on approach, unfortunately I'm no spring chicken and have the equivalent of golfers 'yips'.

[Rich too]

Is it not feasible to use loads of expo instead of rates?

[AVC]

Posted by Rich too on 03/07/2018 12:15:15:

Is it not feasible to use loads of expo instead of rates?

I use them together: the higher the rate, the higher the expo. I would not recommend to use loads of expo, though, especially when it comes to a newbie, because the response is not linear and the more expo, the less linear which could lead to dangerous "jumps" when turning or climbing.

For normal flight mode, I don't use more than 10% for myself, 25% for a learner. If I need special flight modes (e.g. flat spin), then high rates and 30-35% expo

[Rich too]

Soooo, 3D fliers use rates AND lots of expo?

I’ve tried practicing the harrier ( to help improve my landings) and have a feeling I do not have enough elevator movement.

Edited By Rich too on 03/07/2018 12:31:20

[AVC]

Yes, you are right, but this is for the 3d killers err, fliers...

I assume that you are flying a proper 3d model, i.e. oversized elevator, rudder and ailerons (you need them all for a harrier, as you know...). The harries is performed thanks to the flow of air from a big prop hitting a big elevator with a high deflection (45+ degrees), so if you have all these elements, it should work.

As for the expo, yes, you need a lot as you are having a very high rate, and in normal flight you don't want to be jumping up and down all the time. So as I said, expo combined with rates. 

Edited By AVC on 03/07/2018 12:37:03

[AVC]

It also helps a lot to set the CoG as backward as possible, of course...

[Jon H]

I always tell my students to imagine a 5p on top of the control stick and not move the stick beyond the imaginary edges of the 5p. I have the rates set such that the model is responsive but not twitchy. So far in 15 years i have not had anyone yank at the controls such that they made zero progress. Normally they got the feel for it within a short period of time.

Kevin, good to hear you were taught specifically how to use the rudder. I dedicate quite a bit of time to this and even go so far as to disable the ailerons on the buddy box. Its a good way to teach circuit planning as the model is far less responsive and a good way to get used to how the rudder works and its interaction with roll. My current student was cursing my name for quite some time while we did this but when it came to his first cross wind landing, he then understood the method to my apparent madness!

[John Lee]

Posted by simon barr on 03/07/2018 12:04:39:

Its a hobby, guys... If you feel the need to use expo for either training or general flight, then use it.

Why struggle, even with a well set-up model, when all the gizmos are there to help us?

There is no right or wrong, just do whatever you want to do and enjoy!

+1

Why make life difficult?

We have had a couple of members recently that learnt on the Apprentice 15, starting with all the SAFE aids & gradually turning them down/off as they gained experience. It made learning easy for them. It enabled them to have a lot of time in the air and both were solo within a month.

I still fly an ST Discovery as a sports model with 30% expo on aileron & 20% on elevator as it just makes it a nicer flying model for me despite (or because of) my decades of experience.

[Biggles' Elder Brother - Moderator]

An interesting question this one. Two conflicting requirements:

1. If you set a student pilot too much expo then I don't think you are helping them. Large amounts of expo mask the "feel" of the control. A student has to learn this feel and sometimes that will be difficult for them - and "making it go away" by masking it I don't think really helps. Far better, if you can, to support them while they learn to cope with it. Because as they progress they will encounter models where the ailerons and/or elevators really are twitchy - and they have to be ready for that - or at least have taken the first steps towards it.

2. If the aircraft's responses are making the student nervous and almost too frightened to move the controls, then you need to "tame things" a bit for them. A small amount of expo can help here. The student gains confidence and progresses in learning to fly. As long as the amount of expo used is not so much as to mask the control, then I don't see a problem. I don't like really dailing down the rates for such a student as I might need those big throws right now to get him out of the do-dah!

So, a case for, and case against. Which is "right" - well they both are of course! I think as instructors we have to make a individual judgement for each student/aircraft combination. That's where our skill and knowledge comes in, we're not just there to save them from crashing! If we think the student would be better experiencing the aeroplane in the raw state and that will improve their senstitivity of control - then fine, no expo. But if we think the student might benefit from a little expo - then why not. Its a case-by-case thing I think.

BEB

[AVC]

Good summary BEB. As with most things in life, In medio stat virtus

[Nigel R]

"Soooo, 3D fliers use rates AND lots of expo?"

No to the expo.

I use rates (rarely) and 30% expo, which is about what I use on almost everything. I usually only have high rates (landing) and low rates (everything else) if I use them at all.

3D models are inherently super responsive. I think it is easier to get used to that than it is to try and cover it up. High expo makes for really unflyable models - nothing nothing nothing nothing STALL SPIN SPLAT.

Just my opinion, and, for added pinch of salt, I've flown only a few small twitchy 3d models not the big stuff. Although I imagine the above would translate.

[Denis Watkins]

Agreed BEB, in all parts.

The OP specified a Boomerang Mk2, a good stable trainer, no masking required in his case

[Jon H]

I think BEB nailed it. As i said before, I always aim for a model that is responsive but not twitchy.

I do tend to throw my students in at the deep end more than most but they learn faster this way and learn more. If students are wrapped in bubble wrap they will never learn and will pick up bad habits. As for the 'why make it difficult' question, well, it already is. Model flying is not an easy thing to learn so pretending otherwise by 'cheating' their training only sets students up for a fall further down the line, most likely when a far more expensive model is on the line so i would rather give them a more in depth and intensive training than try to make their lives easy.

Obviously changes are made when to suit the student but nothing too major

[Martin Harris - Moderator]

Posted by Nigel R on 03/07/2018 14:16:56:

"Soooo, 3D fliers use rates AND lots of expo?"

No to the expo.

I use rates (rarely) and 30% expo, which is about what I use on almost everything. I usually only have high rates (landing) and low rates (everything else) if I use them at all.

3D models are inherently super responsive. I think it is easier to get used to that than it is to try and cover it up. High expo makes for really unflyable models - nothing nothing nothing nothing STALL SPIN SPLAT.

Just my opinion, and, for added pinch of salt, I've flown only a few small twitchy 3d models not the big stuff. Although I imagine the above would translate.

Interesting - a conversation with a club member recently - a member of a well known display team and recent national indoor 3D champion - revealed that he uses masses of expo with his extreme control movements.

Horses for courses?

[AVC]

Jon, I agree with you in that this is not easy, and I remember having a conversation about cheating with one guy which made perfect and eternal knife edges with a massive Gee Bee R3...using two gyros, one on each axle! This is cheating!

Having said that, if someone is keen to get into this hobby, and we make things too difficult for them, they might give up before discovering the "magic" of facing and overcoming bigger challenges. This is especially important when the newbie is a child, I think. By "cheating" a bit at this stage, we may encourage the person to keep going. I use again the example of my kids: before using the expo they weren't able to keep control for more than 3-4 second, but after using them, the older one was able to do five "eight" figures and even recover it in a couple of difficult moments. He learnt more thanks to the "cheat"

[AVC]

Posted by Martin Harris on 03/07/2018 14:29:35:

Interesting - a conversation with a club member recently - a member of a well known display team and recent national indoor 3D champion - revealed that he uses masses of expo with his extreme control movements.

Horses for courses?

This is also my understanding, although I have never done proper 3D (not even the "improper" one...)

[ASH.]

Expo is great but only in very small amounts. I don't fly 3d so never need the ridiculous 45%+ etc. It all depends on type of model, size and type of control surfaces.

I use 12% max for sport models, I need it. Raw doesn't suit me. ( 13% we had mathematically calculated makes for linear . For a novice flyer who has no knowledge what is best for him or what he would like I would dial in 10% just to ever so slightly smooth out the centre.

Negative 10% on throttle with 2st glow works well too.

[Nigel R]

Martin, you should probably take his advice over mine!

Its definitely a horses for courses thing.

[The Wright Stuff]

I'm going to offer yet another view to add to the confusion, which is apart from the very first one or two flights, I think that to an extent the end effect of expo is often less significant than this discussion is leading us to think. People's brains adapt, alter their response.

Add or subtract some expo, the next flight will feel odd. After that, you'll subconsciously adapt, get used to it, and alter the 'throws' of your fingers without even consciously thinking about it.

So, I would say not piling into the ground through over-control on the first flight is the priority, after that, it's horses for courses, but there will be bigger, more important factors, than the presence or absence of expo to worry about on the training curve...

[John Duncker]

I have taught a few people to fly and don't ever remember resorting to expo. A properly set up trainer does not need it and IMHO it is better if there is an obvious effect on the plane if the stick is moved otherwise the beginner is tempted to jam the stick right over if he thinks nothing is happening.

Flying pattern I use expo on elevator rudder and ailerons as I can be smoother especially when applying corrections. I will have 2 or 3 rates settings with different expo. Learned a lot about this sort of set up from a top us classic pattern guy he told me that this was the way to go to look smooth. Almost as good as transmitter tray and extra long sticks.

I am also a 3D hooligan and have expo on elevator and ailerons . Usually about 40 % If I have overpowered the model I might play around with altering the throttle response low down using the pitch curve option