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View Full Version : *Looping the blade CP*


jakjr
02-09-2006, 06:01 AM
[EDIT] Thread changed, scroll down to bottom of post for details[EDIT]

I attempted looping my BCP again today and had no luck at all.

First try I decided that I would leave it in normal mode, no good. Once it got inverted it dropped out of the sky. This seems to work good on the sim (granted that's with a nitro or large EP copter), but apparently the BCP can't do them in normal mode, or I didn't have it going fast enough. No damages that try.

Second try, put it into idle up and got it going fast, it did a half loop then the tail spun around and it got out of controll. It was, however, high enough up that I did manage to roll it back over and somewhat recover. It did have a pretty rough landing though (bent main shaft, no big deal, can be straightened).

I'm not sure what the problem is here, it seems to me that once it gets inverted it has a mind of it's own. I can do rools, loops, inverted flight, etc. really good on simulators so I don't know what the problem is.

One thing I did notice is that when in idle up the headpseed really drops when you go from positive to negative pitch (i'm not talking about jamming it down from +10 to -10 degrees, just slowly and steadily lowering the pitch into negative degrees does it). I'm thinking the rapid headspeed changes are what's causing the tail to whip around, my guess is the tail motor can't spool up or slow down fast enough to counter the rapid change in torque and thus the tail whips around.

Can anybody here actually pull off decent loops with their BCP? I have seen videos of the pro's doing all sorts of inverted flight, loops, rolls, etc. with it but it isn't specified what kind of mods (if any) the heli's have had done to them.

[EDIT]--------

I now know that mild 3d manuevers are for sure possible with my setup and will now be using this thread to post my looping progress and/or looping questions in, rather than making more threads on the topic.

zappedalaskan
02-09-2006, 05:37 PM
Jak,
You will notice a big difference when you fly your Revo. As you mentioned the collective has a hard time switching pitches very fast and it bogs your head speed, even in idle up mode. This is largely due to all three of your collective servos running full swing at once in order to invert our pitch. The end result is it taxes your all in one unit and robs power from your motors to turn all three servos, slowing everything down a lot. That is why hard 3D guys use mechanical mixing. Your Revo for instance has one dedicated servo that controls the pitch. This makes a big difference for performing these types on moves. On a larger scale this is why 3D guys prefer the Raptor (Mechanical mix) and pattern guys prefer the Hirobo (ccpm) ccpm is smoother for regular flight, but hard 3D is better suited with mechanical mixing.. :)
Jay

jim
02-10-2006, 03:35 PM
I can loop mine. It has to be in stunt mode. Go full neg on the collective as it goes inverted and stay there until it gets verlicle again on the back side of the loop then full pos collective to pull out. Mine comes out kinda sideways for now Im still slow on the rudder
Jim

jakjr
02-10-2006, 06:07 PM
Thanks for the input.

I think I'm going to replace the motors (or at least the tail motor) and give it another go. It still has the original motors in it (which are going on 4 months old!), maybe new ones will help.

Ron S
02-11-2006, 12:16 AM
The last flight I had on mine ,I did 1 loop,went inverted,done 3 spins,and smacked into the garage! Without any control inputs! All ya need is a little Breeze! Come to think of it,I've never needed the stunt mode,it does that on it's own! Ron S:)

jakjr
02-13-2006, 11:09 PM
LOL yeah it seems to be able to do its own stunts rather easily.

Anyways, an update on my looping progress...

Today I managed to keep the tail from spinning around once inverted, but the problem is once it got inverted it got stuck inverted LOL. I managed to keep it under control (or rather keep it from crashing) but couldn't get it to flip back over. Ended up doing an inverted drop (no damages, the blades had nearly stopped spinning before it hit the grass).

Well, at least I know it can fly inverted, too bad I can't get it back right side up once it gets like that though LOL.

I'm gonna give it another go in a few minutes.

Vendetta
02-14-2006, 12:12 AM
JakJr, what sim you using and what controller? Just curious...

jakjr
02-14-2006, 01:07 AM
G2 and XTR.

XTR with an older JR 6 channel radio, and G2 with the one that it comes with.

jakjr
02-19-2006, 07:34 PM
Another update on my looping progress...

I finally did it! I managed to do a full loop without crashing! It wasn't perfect, but I did it :)

I was pretty excited so I gave it another go, didn't get so lucky the second time, once it got inverted it got stuck inverted, again! Needless to say I crashed. So far I'm seing a broke landing gear rod, bent main shaft, possibly a bent spindle shaft, bent flybar, broken CF blade (from what I can tell, one of the flybar paddles got shoved into it), and a broken paddle control frame (a little ball broke off). About $20 to fix it (not counting the parts I already have and the CF blades). Good new is, I might be getting a job at the LHS (owner wants to meet with me sometime this coming week) so I might be able to get a bit of a discount :)

I'm gonna get the little bird repaired, and maybe go ahead and go bell-hiller on it if I can find the kit in stock anywhere, if not I'll see if I can find all the parts to the Esky head. In the meantime, my revo CP will be flight ready sometime next week (just waiting on the rest of the electronics to come in) so that'll keep me busy, I'm not gonna be trying any 3d on it for a while though.

Vendetta
02-23-2006, 06:07 PM
Congrats on the loop ! Oh, and good luck with the job !

L0stS0ul
02-23-2006, 08:57 PM
Congrats on getting the loop down. It's definitally not the most graceful loop that the blade does but it can do it. I managed to capture my first attempts at looping and rolling the blade on video.

http://video.google.com/videoplay?docid=-5258733725216489682

I've actually found that it rolls much quicker to the right than looping it or rolling to the left. It will also get inverted much easier flipping forward than backward.

I just got the B/H upgrade on mine so I can't wait to see the difference once I can take it out to the field. I hate winter. I've been stuck inside all winter. At least my piros are getting better...

Congrats again. It's a huge sense of accomplishment :)