Auto technique question/advice

i'm stuck on what i believe to be the final piece in the jigsaw for my auto technique....so i can finally come off the sim and flick that TH switch with confidence :

how do you control the 'gradient' of the descent so that the heli lands in front of you each time for example ? the relative (from where i'm standing) starting position of the auto in the air is obviously a bit different each time and its apparent i need to slightly alter the gradient (steeper or shallower) to land the heli where i want it.

i'm happy with the negative pitch during decent (keeping this constant right now)
i'm happy holding the heli level or with the nose up a little with elevator during decent (again holding it relatively constant)

this is all on the sim and the model (600 nitro) autos down nicely but i just cannot seem to pick my landing spot ??

do i control the gradient with pitch, elevator or both...or something completely different

any advice guys ?

[Mslater]

any advice guys ?

Practice !

Go up to about 200 feet down wind, fly forwards and flick TH when your angle is at about 45 degs. Negative pitch in and let it float down about half way then flick out of TH and bring back power and positive pitch, fly down the rest of the way on power - then go back up and do it again.

As you get more comfortable with 'the feel' come down further each time without power - eventually you'll feel able to bring it all the way.

[Gixxer]

With the 600, you should be able to flare out sooner than with a smaller heli and you should be able to adjust the flare sufficiently to land it where you want it.

I can get a bullseye almost every time on the sim, but I've only ever tried it once in real life with a 450, and it cost me a few quid in repairs... so you probably shouldn't listen to me

[squareben]

There are a lot of variables to consider steve! I think about energy. Don't forgot when autoing we are essentially flying a glider! you can trade altitude for model speed or headspeed (energy in the spinning blades - the key commodity!) But to do that you need to steepen the decent by pushing the nose down to move the model faster or adding more negative pitch to spin the blades up. You can reduce your negative pitch or pull the nose up and reduce your rate of decent (flatten your glide if you like) but doing this also slows your blade speed and/or forward speed! you've only got so much energy!

I'm no expert but this is what i think about it all! And definitely try it with your biggest heli first! It might seem counter intuitive, but the chance of success is much greater with a 600 or bigger. 450s and 500s are one shot affairs! No errors or its curtains!

[scuba steve]

great explanation ben, Thanks.

which technique do you use ?

for example. if your coming in too steep and the heli will land a fair distance form you if you keep the sticks as is...do you raise the nose or apply less pitch ?

[spiderspid]

I'm just getting to grips with autos , and my method is try to over shoot rather than undershoot, that way you can pull back on the elevator to slow it down whilst still maintaining a good bit of head speed. What did help me was learning the 45% decent that I needed to do for my b test. It gives you a good idea of the angle of approach with the plus that your under power and can just feed in the throttle when you **** it up 8-)
Cheers. Jeff

[Scotvar]

To begin with in my opinion the key to autos is headspeed. I'm still getting to grips with them but I prefer to do them with my X50. I've got a headspeed of over 2100rpm with this heli and it just hangs in the air for what seems like forever and importantly this gives me a lot more time to practice and get comfortable. I run my 700 at a much more sedate headspeed and as a result the blades do not have as much momentum and is not as forgiving as the X50. No stripped gears or cracked skids yet though so I must be getting there!
It's like squareben said, you've only got so much energy / momentum in your blades so I find if they are high to begin with you will have more success initially.

Paul

[Baldie]

Some great info in this Vid by Bobby and Bert, Costs about the same as a pint.... Well worth a look !!


Download Center - SmackTalk RC

[Gav]

Chech out this link for auto techniques

Take a look here - post No.1:

http://www.rcheliaddict.co.uk/main-discussions/56273-autos-time-me-learn-omg-2.html

cheers
Gav

[scuba steve]

thanks for all the advice guys. i've been doing the 45 degree descents (both sides) for a while now and reasonably comfortable with them and some deliberate over shooting is a good idea too.

gunna practice some more on the sim with collective and elevator variations and also flicking the TH during auto descent so it comes a bit more naturally if required in real flight. some one also suggested just auto half way or so and then power back on in real flight....will start with that when the time comes.

SO.....any more takers on control of descent ?

pitch, elevator or both ??

[Guest]

I do some really crappy landings so ...

I use elevator, but it's robbing Peter to pay Paul. What would have been a great auto (except for landing too far away) ends up as a really hard to stick auto (but landing in about the right place) as hustling the elevator brings in a whole situation to try to quiesce - collective, attitude, forward speed all suffer. If I can adjust the approach high enough up (usually with elevator only) then I have enough time to readjust.

I am very interested to hear a qualified answer on your very specific question about control in the descent.

[coolice]

Hey.

Through experience I've come to the conclusion that adding more negative can have a negative effect on head speed during the decent, I think it's to do with the blade being at too high an angle to cut through the air so generates more drag which slows the rotor disk down.
I think by varying the collective pitch and attitude of the model on the way down is key to the final landing position, with practice you soon get used to what the rotor speed is doing during the decent and can learn to trade height/forward speed to land where you want to.

Remember that adding in up elevator during the flare does slightly increase the head speed.

When it comes to practice, I did so by coming down from my circuits in normal mode with minus 3-4 degrees of pitch. This way the engine went to idle and I was in an auto during the decent, but as I flared and increased the collective, the motor would start to power up also for the final brief hover before touch down. This technique suits IC machines more than electric.
However be sure to check your engine throttles cleanly from idle to hover rpm smoothly with no heitation/stopping or you will have entered a full auto ;-)
.

[jamiem]

Autos are a pretty complicated to explain maneuverer, but in practice quite easy; the key is lots and lots of practice!

Start with a bit of forward speed, then just practice simulated approaches, leaving the engine/motor running. You will actually be doing the auto to the point you come out of negative pitch - this bit won't really change wether you have power or not. Get used to an approximate 45degree approach to land in front of your self, do it over and over.

I'll explain the approach in a little more detail as thats the main question in hand. There are 2 key ways to adjust the approach; using collective, and using the elevator. Generally both should be used together to adjust as required. More negative pitch will steepen the decent, but with a steep decent you won't get much headspeed in the flare, so this is where the use of the elevator comes in. Feed a little forward elevator in as you reduce the pitch and this will give you more forward speed and combined with the increase in negative pitch, you'll be in for some decent headspeed in the flare - you convert the forward speed in to headspeed giving you that crucial few seconds to adjust your landing.

You should aim to be flaring a few feet early of where you want to land, so you aren't actually doing a straight 45 degree approach to your feet, but more to say 10 feet before the landing area, this way as you flare you will flatten out the approach and hopefully if you've done it right, you'll land in front of yourself.

When you flare, just pull back on the elevator to pull the nose up. This presents the underside of the disk to the direction of travel, which will spool the blades up. You don't need to adjust the collective straight away, just pull back on the elevator. This will slow down the forward speed, then gently feed in the collective to hover and land.

So, if your coming up short, and you need to extend the landing, bring the collective back up towards zero, and just dip the nose slightly, this will give a much flatter approach, but without that downward speed you won't get much headspeed in the flare.

If your going to oveshoot the landing, pull the node up and reduce the collective. You can go as low as you need on the collective, but be ready to "catch" the model in the flare as it may be coming down pretty quickly if you've had to use a lot of negative pitch.

Autos are easy and great fun, it's just a case of having the balls to flick hold those first few times. If needs be, get in to a hover at only a foot or so, and get used to flicking hold You can also do this really high up and get used to flicking back out of hold, just to see how quickly it will spool back up. Nitros will spool almost instantly back to full headspeed, electrics will depend on if you have a soft start or not (although some have an auto bailout function which reduces this spool up time).

Hopefully this has helped and not confused, any other questions ask away

[scuba steve]

some good advice here and a few great links to other sources of info.

the answer to my question is now obviously BOTH....to land the model where you want you need to set your angle of descent from your starting position and this is done by adjusting both blade pitch and heli attitude (elevator). the higher you start the more time you have to get this right. The objective is to of used up most of the forward speed by the time you get to the flare (which transfers your forward energy into head speed) permitting a nice controlled landing. too much forward speed and you crash in, too little and there is no energy to pass onto the blades so again not ideal. giving too much negative or dropping the nose of the heli on the way down to steepen the angle of descent will give too much head speed...so you could slam in. Conversely, too little negative or too much heli nose up (which gives a more shallow descent) will drop you HS too far and now your not doing an auto your just dropping out of the sky !

its a compromise and i'm sure a patient step wise approach to learning and lots of practice will prevail for me....eventually