Practice those Autos!!!

[hawkman]

Flew for the first time in ages today....must have been near 8 weeks since I flew last.

Zipped around ok....felt fine....went and did a torque turn with the heli almost upside down...pulled out ok and the engine quit!!!!

Holy Moly!!!! I have never had an engine out on me before.....right over the worst possible ground too.....did a quick glance and selected an area....dropped the collective and held my breath....heli floated down and seemed to keep if not increase its headspeed.....flared...and held a hover just inches off the ground....heli settled nicely.

I think I might have overdid the oil content....a bit too much...carried on flying albeit more carefully.

So.....if you dont practice autos...you should...beacuse one day that heli could just quit working...or rather the powerplant could quit.

The heli is a Predator Gasser.....it weighs about 5 kgs....and I use carbon blades set at minus 4 degrees for autos....which seems about fine.

Tips for autos on a sim.....adjust the parameters to get the heaviest heli with the worst blades possible....ie high drag and low weight....a really good way is to set your fuel limit and fly around...just mess about till the engine conks out so you have to auto....its a challenge but could help save your real heli when things do go wrong.

Rob

[3dee]

I think thats a good idea as well. last saterday i was doing autos one after another landing switching out of throttle hold then going back up, going back into throttle hold and landing but i forgot to keep an eye on my fuel and went up and before i could hit the throttle hold the engine stopped. i came down and did the best one, you can hear the blades better when the engine has stopped. my point is if you do loads of autos with the engine on tick over when the time comes to do one foe real its easy your not so scared

[hawkman]

Too true.....there was certainly a silence when that engine coughed and stopped dead.

I reckon its one of the most important skills there is for rc heli flying.

Better to do a slightly duff auto than have a total write off on your hands.


I good practice method I use on the sim is to time the fuel....ie 2 mins of fuel...then do some balloon popping...when the engine conks out you then auto.....its better to forget the fuel level and bust as many balloons as possible....that way you get to do autos without thinking about it too much...the sim I use is 'Phoenix' though other sims must have similar things.

Rob

[3dee]

Hi i find the sim that not good for autos the wind is always a bit different on the field and you can not see the ground till its too late on the sim. plus mine has a glitch which means if i land flat, no matter how hard it does not crash so not really any good to do autos. yours is probably different

[j42]

Hello please can someone explain how you do Auto's thanks

[hawkman]

If the engine conks out its possible to still land the heli and keep it in one piece.

Most model helis have a 'one way bearing' this allows the blades to freewheel.....if you are flying around and the engine dies out....very possible with a nitro, petrol or gas turbine engined heli....not so common with electric helis.....because you have a free turning rotor you can use the air rushing through the rotor disc (because your heli will be going down!) to keep the rotor turning.

With the turning rotor we can slow the helis descent....and build up rotor speed....or at least maintain it....becuase once we get near the ground you need that reserve of energy to steadily slow the helis descent.....and then gently set it down on the ground.

To do this you need 'negative pitch' so with the collective stick down there will be say minus 5 degrees of negative pitch....ie the blades trailing edge will be pointing up slightly.

Autos are hard to do....at first.....you must get a simulator and try it out....Phoenix (my current sim) has an auto practice feature....you click on it and you get your chosen heli just launched at you from a height (which you can select) this forces you into having to land it....and try to keep it in one piece

Try it out....its a deep subject as you realise the forces involved....and its something that might just save your helicopter should a real engine failure happen.

Heavier blades equals good energy reserve, but basically a good sim will allow you to alter the parameters of the model...so you can experiment...its all about conditioning your reflexes....beacuse if you dither in a real emergency you could end up with a totalled heli....I would rather a slightly messy auto than a total wreck.

Rob

[j42]

Originally Posted by hawkman

If the engine conks out its possible to still land the heli and keep it in one piece.

Most model helis have a 'one way bearing' this allows the blades to freewheel.....if you are flying around and the engine dies out....very possible with a nitro, petrol or gas turbine engined heli....not so common with electric helis.....because you have a free turning rotor you can use the air rushing through the rotor disc (because your heli will be going down!) to keep the rotor turning.

With the turning rotor we can slow the helis descent....and build up rotor speed....or at least maintain it....becuase once we get near the ground you need that reserve of energy to steadily slow the helis descent.....and then gently set it down on the ground.

To do this you need 'negative pitch' so with the collective stick down there will be say minus 5 degrees of negative pitch....ie the blades trailing edge will be pointing up slightly.

Autos are hard to do....at first.....you must get a simulator and try it out....Phoenix (my current sim) has an auto practice feature....you click on it and you get your chosen heli just launched at you from a height (which you can select) this forces you into having to land it....and try to keep it in one piece

Try it out....its a deep subject as you realise the forces involved....and its something that might just save your helicopter should a real engine failure happen.

Heavier blades equals good energy reserve, but basically a good sim will allow you to alter the parameters of the model...so you can experiment...its all about conditioning your reflexes....beacuse if you dither in a real emergency you could end up with a totalled heli....I would rather a slightly messy auto than a total wreck.

Rob

Thanks for the explanation much appreciated what is the best hight to practice at as I don't have a sim or do you need to be quite high for it to work.

Thank you

[hawkman]

Height? I would go as high as possible....and do some steady descents followed by a nice gentle landing.....get this right without dithering and you are almost ok to try a real auto.....dither and you will ruin your heli....because if you spend too long trying to hover during an auto you will loose rotor rpm which will end in disaster....the heli will drop like a stone.

When you are ready, set your throttle hold...but INHIBIT it.....so this way you can fly about...get some height....flip the throttle hold switch....and make sure that collective is DOWN....because we want negative pitch....the heli shouldnt plummet out of the sky....a nice steady descent....push the collective up nice and steady as you reach the ground....slow that heli up....and land as gentle as you can.

By inhibiting the throttle hold you will program yourself into landing without thinking too much.....when you feel ready....activate the throttle hold and go up nice and high....flip the hold on while lowering the collective.....you will hear the engine idling.....and you should hear the blades making a nice swishing sound....you might even hear the rotor speed picking up.....the heli should drop steadily...but not plummet....you want about minus 4 or 5 degrees...too much will let the heli drop fast and can actually decay the rotor rpm.

Keep the heli slightly nose up....NOT NOSE DOWN....and keep it heading into the wind....let the heli drop steadily....if you chicken out then hit the throttle hold and get that engine back on line....climb away steadily and try again....

IF you have a failure...ie engine has conked....DO NOT PANIC....just let that heli drop nice and steady....and as it gets close to the ground raise the collective but not too much....let the heli settle down onto the ground...DO NOT LOWER THE COLLECTIVE TOO FAST ONCE YOU LAND!!! doing this can induce a blade to strike the boom.....you will hear a 'crack' and the heli will end up on its side.

Low height? if you are zooming about and the engine conks out its all down to judgement...and split second timing.....you will be low but should have a good headspeed....just aim to land as quick as possible....keep that collective lowered....but not too much....fairly heavy blades will hold a lot of reserve energy.....good practice is to zoom about....and then land without hesitation....take it easy though beacuse if your field is rough you can end up breaking the heli for no need.

I would get a simulator....I cant stress this enough.....I good way of learning to auto on this is to set your fuel level/time and zoom about....ignore the timing.....when the model runs out of fuel you have to auto....chances are if you can crack auto on the sim then you have a far higher chance of success in real life.

Another bonus of autos is that if your tail rotor fails.....and the heli just spins like a lunatic....you can climb out and then hit throttle hold.....do this at height and you can then steady the heli down with the cyclic....using small movements and then land the heli, hopefully keeping it in one piece.

What heli are you flying?

Rob