49 seconds to disaster.

[dillwhacker]

Oh well, never mind!
Summer is coming,
The geese are getting fat,
Please put a penny in...
Oh sheet - splat!!
You take care, have fun & be good!
TTP
(Trev The Plummet)...

[carper2k]

Hi Vikki
i know this is off topic but a tip for you with the Gaui 330xs is stick a 10 pence piece under the control unit this helps with vibration by altering the cog of the controller and set it up without the green wire in just use the trim pots at first

Paul

[dieselcarb]

hi vicky that might of been me that mentioned the skids i got em on mine i think they look alright. might trim the tubes 1 day though, but great on eneven ground. they fly just like the originals (well i didnt notice)

[cjcj1949]

I don't know how trim works on a flybarless like your late smaller heli but on gyros it depends on which gyro and which mode. In rate mode you can use your rudder trim to get the tail stable and then from the number of clicks you can get back to zero trim by adjusting the servo position. Usually you need an offset of about 5 degrees on the tail rotor blades. In hold mode the trim is usually assumed to be mechanically correct after being set up in rate mode. So the trim is usually zero. In hold mode zero trim is assumed by some older gyros to be the no rotation setting and this is why some people think that gyros will only work with no trim, or trim set to zero. Newer gyros look at the rudder setting during initialisation and use that as the zero rotation setting. So you can with most gyros have some trim in to compensate for an imperfect set up and still have it work in hold mode. Different gyros will have different capture amounts.

After initialisation though the rules change. Gyros are temperature sensitive because of the components they use. The temperature changes after initialisation and the gyro will tend to drift in heading hold as its sensor and the electronics memory of no drift changes. All you then do is to put in some trim to change your own definition of no drift. Luckily for you most of these temperature effects have now been eliminated by better design. (Mems)

To further complicate the issue, modern gyros are often so good that they don't require an accurate mechanical setup unless you want to fly in rate mode. The gyro will find the correct offset to stop rotation as it can't tell the difference between a mechanical offset and a sidewind.

When the heli is on the ground, the gyro is unable to control the direction the tail is pointing in. This can result in the gyro moving the tail to one side or the other. This can result, with some gyros, in a very large rotation at lift off. This can be eliminated by switching into rate mode just before spooling up.
It can also happen if you switch on and initialise in one place and move the heli to another for take off.

I switch into rate mode and throttle hold as soon as the gyro and esc have initialised.

The reason for the strange behaviour is that gyros aren't gyros at all. They can only measure rotation in yaw. They use integration of yaw rate to produce a stable angle. Normally this works very well.

[Vikki]

Carper, thanks for that info.

Diesel, thanks for that skid tip, you're a star. I've corrected the post that was wrong.

CJ, realised I was thinking of flybarless without realising it, d'oh! On Chopasaurus gyro only controls tail, I can be dense at times. Thanks for the info, most useful.

How do you switch to rate mode and why would you do it? So much to learn

Best regards.

Vikki.

[Audi_TT 83]

Or.... how I dumb-thumbed Chopasaurus sideways on into planet Earth!

A wonderful calm day. Can't feel a stir of air movement. The only movement was an involuntary internal one.

I know what happened, I listened to my brain (stupid really). I saw him going in sideways and went to catch him but, from a long way away I had my brain say "Other way, Stupid!" And Stupid listened and Stupid pushed her thumb the wrong way and Stupid planted her helicopter into the ground and Stupid thought, 'Gee, I wonder how much water that'll take to grow into a 700e?'. Like - none at all STUPID!

I know why it happened. I spent too much time practicing nose in on the sim and I couple of times I'd caught myself wrong sticking it when tail in. D'oh!

So, what's the damage? About a fivers worth. If you bear in mind that parts come in twos. So, bent flybar, busted blades (already have a set), bent feathering shaft (have one of them), stripped main gear (don't have one of them). Servos feel ok, main shaft may be bent, don't know yet but I've got two of them (ordered just in case last time).

I was close to giving up - for 5 minutes, 2 minutes? 1? Well, what's a fiver and a bit of interesting work and a lesson well learned? Priceless!

Here it is, in all its embarrassing glory: How Stupid planted a Blade 450 thinking it was a Sunflower!

49 seconds to disaster. - YouTube

Best regards.

Vikki.

i can tell you are female from this (keep reading its not an insult) even though i am sad that it went in, a smile was brought to my face from the beautiful way in which you wrote about what happened. its amazing that the sub concious part of people brains can override what you know to be true, i.e it was going forwards and to the right but suddenly its swapped without you noticing so it must be right, oh no its not, its now a crumpled heap in the floor

[Scooby]

Hi Vikki,

I've found that the 500 gear mod really helped me too as my back garden is pretty awful, and the wider stance and better tail clearance give me a lot more confidence if I'm not completely level on landing or its a bit gusty (I think I also mentioned the 500 skids idea in one of your other threads). I think it also makes the thing look a lot more rugged too, which I like!

Good job on getting Chopasaurus rebuilt, and fingers crossed for good weather (and a good flight) on Wednesday

[Vikki]

Thanks, Scoob.

I've also corrected my post to reflect it was your suggestion I change the skids (checked other post ).

Thanks for that, Scoob. He looks great with his big boots on, hehehe.

Vikki.

[Scooby]

No worries, I can't claim credit for the idea anyway - I first saw it on a rival forum!!

I just need the rest of the 500 to go with the gear now.....

[cjcj1949]

Some people would claim that hold mode is cheating. It does make hovering in gusts much easier and flying backwards is not much more difficult than forwards. It makes the first part of the A test very easy as sideways travel requires no tail correction. It does make the second part much more difficult though, as the tail has to be controlled all the way through the lazy eight. In rate mode the tail follows the direction of flight and requires less correction in an eight. The faster it is flown the less correction is needed. To get rate mode set the gyro sensitivity to about 25%. Anything over 50% is hold and under 50% rate. 25% and 65% usually work ok as starting values. It is generally more difficult to fly with rate as the tail position can change. It is useful though for centering the tail before takeoff. If you can do this as the heli spools up or if you don't need to then rate is just another flying style.
I used rate when I started as my gyro was very unreliable in hold mode when it got colder. I didn't find hold mode much of an advantage when hovering, but if you want to fly the heli back to you while tail in you will need hold mode as in rate mode it would turn into nose in, which could upset a flybarless person. It is more natural for a plank person though, as that is how they fly.

[Vikki]

Thank you, CJ. I understand.

Vikki.

[dieselcarb]

I just need the rest of the 500 to go with the gear now.....

hahahahahaha bet ya got 1 way b4 summers out too good luck with wording that to the better half