Flight Training videos - Sim and real life!

[TheBum]

Excellent! Thanks for the addition and I look forward to more such additions.

[TheBum]

Hey Finless! Are you still planning to capture and post the "great" exercises you mentioned back in March?

[Finless]

maybe..... I just gotta get the time!

Bob

[Finless]

Thread updated and a new video REAL LIFE added.

Bob

[ignis]

can someone briefly explain the point of auto rotations? isn't it easier to just land a heli by lowering the throttle?

[TheBum]

Yes, it's easier, but it's also more challenging to land the heli in a particular spot when it's unpowered. One of the most impressive autos I've ever seen was done by Finless in his "unauthorized" Diablo flight video. He nailed the landing dead center on his small heli pad.

Besides, autos have their practical uses -- landing with a dead battery, snapped belt, etc. -- which require practice to be ready for.

[piwko4]

Ive got a request Bob... I was wondering if you could teach us piro flips. I know what stick movements are needed, but cant really figure out the cordination and what technique to use. Thanks

[Finless]

I wish I could! I cant do them! I am learning to piro in one spot now upright and inverted (both directions). Until you can do that you SHOULD NOT be learning piro flips in my opinion.

Bob

[TheBum]

I learned a whole bunch from your "real life" video. I had it all wrong when I was practicing in the sim (trying to use negative pitch to keep head speed up instead of forward speed). Can anybody explain the principle that's responsible for being able to maintain head speed with forward speed? It just seems counterintuitive to me.

[sschulze]

I could be wrong about this but the forward speed doesn't help you MAINTAIN headspeed, it's just that when you flare at the end it GIVES you headspeed

basically you give the heli some forward speed at altitude where you can take the "hit" in headspeed because you have altitude left to gain it back, then you flare at the bottom to get extra headspeed and you use the potential energy from dropping

the forward speed is kinetic energy, which is transfered to the blades via flare, starting up high is the potential energy which is transfered via increasing pitch

someone correct me if I'm wrong but this is how I understand it

[Mike3DPro]

Can anybody explain the principle that's responsible for being able to maintain head speed with forward speed? It just seems counterintuitive to me.

Now don't quote me on this because I may be wrong. I dont know about how forward speed will help actual headspeed (I think it does) BUT I am pretty sure one of the factors is that a helicopter has a downwash and if you were to hover in one place the helicopter would have to work slightly harder to maintain a hover because of it. However, if the heli is continously moving forward, if will always be coming into "fresh" undisturbed air, and thus have to work less hard. Hope that helps.

Someone please correct me if I'm wrong.

Edit: I see some one has said almost the same thing. What we need is an engineer to explain to us. :)

[Finless]

Well this speculation is not the case and not why...

This is where I wish SPORK was still here... He would be on this question like stink on... well you know... I can answer it myself but not like Spork could. Alas he left for reasons I wont go into... I know he check stuff here and I would like him to come back a realize WHERE he is needed and that is questions like this!

I will give him a day or 2 to chime in ( I hope he does) but after that I will tell you why.... HINT... think a wing JUST like an airplane ;)

Bob

[sschulze]

this is basically what I said Bob, it doesn't help you maintain your headspeed, it just "gives" you the headspeed at the flare because you don't need to feed in pitch as fast

when you flare it increases the angle of attack the blades have which produces more lift, which slows the rate of descent, or "flares" as the term is used by not only decreasing rate of descent but actually allowing you to climb

so the answer to the question is that foward speed does not MAINTAIN, or in essence really give you headspeed, it just means you use LESS headspeed earlier because you can rely on the flare+increse pitch instead of just relying on just increasing pitch

(of course all the headspeeds ends up being used in most autos, so you use LESS headspeed EARLIER in the auto which means an easier/smoother auto in the end)

edit: just wanted to clarifly in this post (and my previous) when I say "gives" headspeed I really just mean it "helps", i was trying to explain in layman terms, i'm an aero engineer and don't think explaining in true technical fashion will get the point across here, if you're interested in that there's plenty of sites that explain auto's with good pics/descriptions

[skid]

2 words- glide angle. That makes it all come together. It gives you forward speed and with neg. pitch, forces the blades to keep spinning and not stall. Flaring wont give you headspeed. It will give you lift from the kinetic energy stored in the blades.

[Mercuriell]

GLide angle's right - you have to regard the rotor disc as not just a fan blowing air but a wing - if you pull back cyclic in FFF you go up due to increased angle of attack of the rotor disc and lift generated (unless you synchronously decrease collective) - flaring during the last stage of auto increases lift in the same way at the expense of headspeed which drops as its stored kinetic energy is dissipated in air and mechanical resistance.

[Finless]

ding....ding....ding....ding.... I think we have a winner :)

Bob

[sschulze]

what was said about glide angle and angle of attack is true, but I'm surprised no one has pointed out the fact that forward speed does not maintain headspeed for you! this is an important concept to understand if you want to fully understand autos completely! the necessity for negative pitch (no matter how small it is) is because forward headspeed does not maintain the headspeed

we all know that you can drop straight down from the sky with full negative and have tremendous amounts of headspeed, and this is simply what gives you the headspeed in an auto, falling from the sky with a little bit of negative pitch, we also know this is NOT the way to perform an auto from altitude, you'd just be dropping way to fast

here's why forward speed is used in an auto: you can get the close to the same headspeed dropping straight down WITHOUT dropping straight down! the reason is because the forward speed gives the blades lift much like forward speed on the wings of a plane give it lift! This extra lift slows the decent of the heli which makes autos MUCH easier to do, the forward speed also allows for a flare near the ground which is a huge benefit as well

what has been written before by me and Mercuriell about the flare is 100% true, I just wanted to clarifly what was going on before the flare

I hope this makes sense as I am engineer and know that I can't explain these technical things in an easy way to understand all the time

[Finless]

ding....ding....ding....ding.... Another winner and an excellent elaboration on the principle and why FF is a good thing!
Actually a 450 sucks at straight down autos! Not that it cant do them but it is harder. We need the 450 to have it's rotor act like a wing to get the most out of it.

Some folks are really JAMMING down elevator in an attempt to really get some forward airspeed... Like a wing this can be bad and now your using the wing (or rotor) to force the heli down and this uses energy! For a heli this is worse and uses head speed. So there is a fine balance here for best auto performance.

Thanks sschulze great build!

Bob

Bob

[TheBum]

Wow, I had no idea that my seemingly innocuous question would generate so much good discussion. Thanks one and all.

[trexflyer02]

Thanks for the video Finless. I just dumped my V2 because of an auto (even though I had done about a dozen before perfectly). I came in a bit too fast, which was no problem if I would've flared 1/2 second before. This is my second helicopter, my first "auto-able" helicopter, and also my first crash. RealFlight G3.5 ROCKS!!!!

Anyways, no more autos for me for a little while because I replaced my Align 325 white Carbons with Curtis Youngblood Radix 325s. I know the Radix blades are supposed to auto well, but I'm not about to go risk $45 just because of a little boom strike :p .

Thanks,
trexflyer02

[Finless]

$45 just because of a little boom strike :p .

BUCK... BUCK... BUCK..... I wish we had a chicken emoticon as I would use it ;)

Dude just GO FOR IT and you will find with CF blades it is WAY easier and rewarding ;)

Bob

[trexflyer02]

BUCK... BUCK... BUCK..... I wish we had a chicken emoticon as I would use it ;)

Dude just GO FOR IT and you will find with CF blades it is WAY easier and rewarding ;)

Bob

Thanks for the encouragement, auto master :noteworthy

I haven't even flown the new blades yet, but I'm very impressed with the T-Rex so far. My first crash was about $25 not including blades. If I crashed the same way with my now-sold Blade CP, it probably would've been at least $10 more than that.

I actually set up a T-Rex in RealFlight primarily for auto practice ... which is configured with VERY light blades (and heavier paddles to accomodate the change) for better simulation of the float time at the end of the auto. I find RF an invaluable tool in learning to fly RC.

Back on the REAL heli side ... what do you guys think of the 325mm Radix blades? I've heard what people say on other forums, but since I haven't been a member for very long on this forum, I want to know what the FREAKS have to say!

-trexflyer02

[dallasd]

You asked for it YOU GOT IT!
Just added learning basic loops using the simulator.
Link is on the first post of this thread.

Bob
Wow, that was quick. Thanks a bunch for the Loop video. The view of the heli and the collective stick position says it all. I'm on my way outside to give it a try.

Thanks again,
Dave

[jgiot]

Hi,

Thanx to Bob, watched his loop vid, went outside and did it.

Can we have a roll vid now?

Thanx

John

[Finless]

Roll vid coming soon!
It will not be on the sim it will be in real life using the stick cam!

Bob