A cautionary Tale

[cymaz]

At our club today a pilot was getting ready a plane he has already flown on a previous weekend.

During the week he changed the aileron servos. In the pits he did all his preflight checks.

On take off the plane veered left into the pits, crashing only 8 feet from other pilots. On inspecting the model the ailerons were reversed.

A major accident was narrowly averted, luckily.

If you do any work on a plane and take it to the flying field it might be good safety practice to get someone else to make sure everything is moving in the correct orientation.

The pilot had checked the ailerons but had not registered that they were reversed.

[Pete B]

Commiserations and a lucky escape for him, Cymaz.

Imperfect as I am in many respects, the reversed-controls fail never ceases to amaze me, as I've a habit of giving all the sticks a tweak to confirm direction before every flight - just a habit I've got into over the years.... I often catch myself murmuring as I go through them, too....

Pete

[Biggles' Elder Brother - Moderator]

The problem I think is that too many pilots take pre-flight test for granted. A quick wiggle of the sticks - if everything moves then its OK. That's not nearly good enough.

Its vital to make the conscious effort to really look, not only are they moving, are they moving the right way! And do it every time. It all about forming the habit - make a point of doing it and soon you do the full proper check before every flight - even if you've flown the model earlier the same day - still fully check.

I'm sorry for your mate Cymaz - but there really is no excuse for taking off with control surfaces reversed - its just sloppy airmanship.

BEB

[Biggles' Elder Brother - Moderator]

Snap Pete!

[fly boy3]

Hi Pete, I was also taught this way too, 25 years ago, as you say before every flight as well.  Worked ok for me. Cheers. ps, Hope the model was not damaged badly.

Edited By fly boy3 on 26/07/2014 21:44:26

[Ian101]

I watched a bloke today start his ic engine, do his pre flight checks and a full power engine run while he was sat on the grass directly in front of the prop! His model had a tail restraint, but.................

Sorry, slightly off thread but also dangerous.

[cymaz]

Posted by fly boy3 on 26/07/2014 21:43:08:

Hi Pete, I was also taught this way too, 25 years ago, as you say before every flight as well. Worked ok for me. Cheers. ps, Hope the model was not damaged badly.

Edited By fly boy3 on 26/07/2014 21:44:26

His model was totalled

[Concorde Speedbird]

I was taught to as well just before take off. Before every flight- ailerons, the direction you move the stick the aileron in that direction should go up, elevators, fairly obvious (watch it doesn't nose over) and rudder. Throttle done in power check previously.

I'm glad the accident caused only model damage.

CS

[John Privett]

Posted by cymaz on 26/07/2014 22:50:11:

His model was totalled

Sorry to be a bit blunt, but hopefully that will serve as a powerful reminder to him (and others) in future.

Anyway, better to write-off a model than to injure somebody with it.

[The Wright Stuff]

The pilot had checked the ailerons but had not registered that they were reversed.

This is the key line for me. Does this mean that the ailerons were checked simply to be moving in response to the stick, or was it a case of checking for direction as well, but then having a 'brain-in-neutral' moment when interpreting the check? I guess I could perhaps at least partially forgive the latter - particularly with ailerons - we all have these 'senior moments' from time to time, particularly if there are other distractions around, and a pressure to get on with the flight with other pilots waiting...and I'm not sure from the OP how experienced the pilot was.

Well, a lucky escape in the sense that no-one was hurt. Or perhaps, (credit where credit is due) the fortunate escape was a result of starting far enough away from the pits in the first place (did the model actually get airborne?) I agree with the importance of pre-flight checks, but I think an equally important fact in this particular case is that he had changed the aileron servos and not checked at the time that the direction was still ok. Was this a case of a 'mental note' to check them later being forgotten, or was even the possibility that the direction was reversed completely missed? It might be that since this is something that is less critical to set up correctly in the hardware (compared to the 'old days' of having much less transmitter-based set up) then there are more opportunities to forget things like this, but perhaps that is a different can of worms...

Thus he had two opportunities to discover the problem: first when he changed the aileron servo, and then again in the pre-flight check before the flight. This to me is the crux of the matter. I understand and acknowledge that I make mistakes occasionally: my work lifestyle means that I am often tired when I'm flying, and so I try to mentally step through stuff in a way that gives me 'several mistakes' leeway. For example, I ensure that I set up all my models with the aileron servos going the same way, and roughly set up with the same rates on the transmitter. That way, if I ever mistakenly had the transmitter set up for the wrong model (and it's never happened so far...) it would at least still be flyable (i.e. I could complete a circuit and get it down again). Yes, it would be far, far better to not make this mistake, but I prefer to cover that base anyway. In the same way, the pre-flight field check should be the final, double, or triple check! A final opportunity to spot something is wrong.

As BEB, Pete and CS have said, a proper pre-flight check would have revealed the problem, but perhaps my view is that this is something that should have been discovered long before then...

[cymaz]

A lesson to us all.

As has been said ,but very important, pre flight check is just that. Not a stick waggling excersise.

I have several 1/4 scale models ( as I'm sure several fliers do ), I printed up a preflight check list and read it off from top to bottom....

1. Correct model on Tx
2. Fail safe working
3. Check all clevises
4. Check wing bolts

And so on.

[cymaz]

Posted by John Privett on 26/07/2014 23:23:15:

Posted by cymaz on 26/07/2014 22:50:11:

His model was totalled 

Anyway, better to write-off a model than to injure somebody 

I'll second that, it came down 8 ft behind me as I was sitting having lunch.

Edited By cymaz on 27/07/2014 06:04:40

[leccyflyer]

Posted by Biggles' Elder Brother - Moderator on 26/07/2014 21:39:07:

The problem I think is that too many pilots take pre-flight test for granted. A quick wiggle of the sticks - if everything moves then its OK. That's not nearly good enough.

Its vital to make the conscious effort to really look, not only are they moving, are they moving the right way! And do it every time. It all about forming the habit - make a point of doing it and soon you do the full proper check before every flight - even if you've flown the model earlier the same day - still fully check.

I'm sorry for your mate Cymaz - but there really is no excuse for taking off with control surfaces reversed - its just sloppy airmanship.

BEB

I cannot count the number of times that I've said exactly that. Take the time to consciously observe the movement of the control surfaces, especially ailerons. I like to work through the sequence "Left aileron stick, okay, the right aileron is going down, that will lift the right wing and the aeroplane will roll towards the left. Right aileron stick, the left aileron is going down, that will lift the left wing and roll the aeroplane to the right. " and so on.

I got distracted (twice) recently and hand launched with reversed elevators on a model that I had been playing around with the set-up. There is sometimes even a clue that something isn't quite right. Just yesterday, taking the time over the preflights saved my model. I switched on and selected the correct model, or so I thought, but the aileron trim was slightly out. I could have sworn that I had set it up correctly, but it needed several clicks of aileron trim to level them.

Ran through the pre-flights prior to launch - noticing that the ailerons were reversed. Corrected the reversal, a bit puzzled and then my clubmate, who was launchng for me said that I had quite a bit of aileron trim on. That out of trim situation was a clue. The pre-flight had picked up the reversal, but I should have picked it up earlier, before even waggling the sticks, when the trim was out.

[cymaz]

I think we all must have had a slip up now and again, human nature. I myself have turned on the Tx and model and thought something is wrong. Only to find out its the wrong model after 5 mins of head scratching.

I'm not pointing fingers or blame - I just wanted to let fliers know about the consequences of their actions and hope from that an injury is averted.

[David Davis]

I picked up the following tip years ago.

1. Stand behind your model.
2. Push your aileron stick to the right and the right aileron should come up to meet it.
3. Repeat the process for the left aileron especially as we frequently use different channels for the two ailerons these days.

[cymaz]

Posted by David Davis on 27/07/2014 06:50:20:

I picked up the following tip years ago.

1. Stand behind your model.
2. Push your aileron stick to the right and the right aileron should come up to meet it.
3. Repeat the process for the left aileron especially as we frequently use different channels for the two ailerons these days.

Correct David, you would think it would be that easy. I have known 2 other incidences of pilots trying to fly with reversed ailerons.

Edited By cymaz on 27/07/2014 07:24:37

[leccyflyer]

That's the trouble though - if you use a mantra like "Stick to the right, right aileron up" or similar, there is a risk that it becomes a mantra and you don't take the time to actually look at the surface. So, even when the surface goes down, and the controls are reversed, you've "done" your preflight and are ready to go.

Personally I've seen many, very experienced pilots take off with reversed ailerons, it's not at all uncommon and it usually ends in disaster.

It's a great tip to make sure to check both ailerons too.

[Peter Miller]

We have all done it at least once.

Ron Chadwick, the chief designer at AVRO was killed on a test flight of the Avro Tudor because THE AILERONS WERE CONNECTED UP TO GIVE REVERSED CONTROLS.

On full size aircraft the fitter does the work, the supervisor checks it and then when controls are involved an independent check has to be made.

Edited By Peter Miller on 27/07/2014 08:22:14

[David Hardaker]

Not long since I had to change a Futaba 3003 servo. So I installed another 3003 servo and hey presto, it was reversed. The badge was slightly different but both said Futaba 3003. So one of the servos was "probably" of spurious manufacture.

Murphy is out there, beware !

[Dave Hopkin]

Concurr - very recently, I had taken one model up for a couple of flights, then a coffee and a natter break - put another battery in and looked at the ailerons - both were UP at about half deflection..... god knows why... powered down and up again and all was ok.. never found out the cause

I also find I am utterly incapable of checking the ailerons are going in the right direction from the front of the plane, I have to stand behind it, and then I find myself leaning slightly in the direction of the stick to check the things.....

[David Hardaker]

What was in the coffee !!??

Joking apart, the most important thing about checks is to be consistent and avoid distractions....(sometimes easier said than done)

Edited By David Hardaker on 19/02/2015 10:10:00

[bert baker]

No bodies fool proof, it wont be the last time it happens.

Hindsight control, rudder rudder rudder forget the ailerons.

Not an easy thing to remember two inches of the ground.

Just after a hand launch the plane I was going to fly caught a cross wind gust and went into a knife edge and would not return the way it came from. I often ponder if it would have been better to roll it more and push out inverted, easy thing to think of after the event.

[Erfolg]

As one who has been caught out very recently by a similar issue, it is so easy to become pious and sanctimonious about any mishap.

In my case I had made many checks at different points. I am trying to say I did nothing wrong, I obviously did.

Just to bring some down to earth, not so long ago, maybe 5 years. I listened to some one who was our then safely officer telling all assembled how we should not do this and that, and how he never, ever, under any circumstances would not do or take certain actions, if only we followed his example. I did think at the time, a saint if ever there was one, similar to the Pope in being infallible.

I know you know what is coming. I have seen and witnessed that three of the things that he would never do, and consequences which could be avoided, happen to the self said person. Different occasions, all different types of events.

Reality is, that every single person who has done anything, will have made mistakes, and will continue to do so.

I endeavour to learn from my mistakes, and accept there for the grace of God go I. In my case, I now realise that I should have undertaken a final check of the systems as a whole in a sceptical manner. Rather, than taking the view that once a setting is crossed of the check list it will remain as set.

I thought that my failsafe had failed, as two servos controlled via a mix, were both in a non neutral position, on examination. On a post crash check, the failsafe does work as set. In this case there is a mystery, which hopefully is of no importance.

It is easy to say this and that should not happen. Yet I think there is another lesson, if a lot of repeated checks are made, they become ineffectual, or can do. There is a danger that you see what you expect to see. From this I will not place much importance on the intermediate checks, seeing them as indicative. There needs to be a final check of everything as an entirety. Although I did a final check at home, the importance of this check was not appreciated. being seen as confirmatory. Rather than taking the view, there is a good chance things are not right, as things that may have been correct initially, may not have remained so.

One final thought, I was taught that 100% inspection, does not guarantee that the items are 100% right. There are many reasons why they may not be.

[kc]

Of course I don't know the layout at your club or how far into the flight it happened but two things occur to me......

!. shouldn't everyone START the takeoff run BEYOND the line of pilots & parked aircraft

and

2. Might depend on model a bit but maybe should be using rudder rather than ailerons at takeoff? So he is likely to have been airborn and therefore have taken off well before the other pilot line! Or could the " reversed servo" have been just an excuse and he just hauled it off too steeply with too little speed?

But as everyone said these things happen if you don't check properly.

[Jon H]

I have to confess, this one is something I try and drill into any trainees at my field to the extent that I will deliberately reverse their ailerons on either the master or buddy box to see if they pick it up. I will ask them if its all ok and if they say yes (and its the buddy box I changed) then off we go to fly. It comes as quite a shock when I give them control after take off and its all the wrong way round.

It might sound mean and that I am trying to trip up students, but the purpose of the exercise is to show that just because its wiggling about dosent mean its correct.