HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Apr 20, 2001, 07:19 PM
Thumbs a blur
Augeredin's Avatar
Allen,Texas USA
Joined Dec 2000
126 Posts
Never exceed speed

Didnt know my zagi had a never exceed speed. Dove from about 400 feet straight towards terra firma and it stutterd a little then the violent oscilations began.Flapping like a sick bird on some sort of go fast drug it jettisoned the battery are top canopy and dropped the remaining 100 feet like a paper plate. I stood in amazement.:0
This is what happens to zagis, does anyone have a similar story with a different plane?
Augeredin is offline Find More Posts by Augeredin
Reply With Quote
Sign up now
to remove ads between posts
Old Apr 20, 2001, 07:26 PM
Registered Snoozer
Neil Morse's Avatar
San Francisco, CA, USA
Joined Jul 1999
6,139 Posts
There's a video of this phenomenon on Steve DiStasio's website:
http://www.squid-ink.com/hpn/rc-photos/index.htm

Neil

Neil Morse is online now Find More Posts by Neil Morse
Reply With Quote
Old Apr 20, 2001, 07:33 PM
Quiet Power
USA, CA, Citrus Heights
Joined Mar 2001
431 Posts
Strange Behavior I'd say.
Does yours have the Carbon Fiber Rod?
I saw a cool video of a zagi folding or "Flapping Its Wings" at http://www.squid-ink.com/hpn/rc-photos/.
I've put mine into some very steep and fast shots at mother earth and it just pulls up for me. believe me, it has nothing to do with my ability, simply the carbon rod. if yours doesn't have one, install one and re-adjust your CG.
Tom
costath is offline Find More Posts by costath
Reply With Quote
Old Apr 20, 2001, 07:35 PM
Quiet Power
USA, CA, Citrus Heights
Joined Mar 2001
431 Posts
Neil,
Great minds obviously think alike. Looks like we were repsonding at the same time, with the same response. You win as I got interrupted by a business call. How rude, right in the middle of me cruising ezone at work.
Tom
costath is offline Find More Posts by costath
Reply With Quote
Old Apr 20, 2001, 07:40 PM
Registered User
Sabrejock's Avatar
Winnipeg, MB Canada
Joined Jan 2000
2,419 Posts
Zagi flap! It also happens to other wings. IMHO, as I'm not an aeronautical engineer (otherwise I would not be humble!), this phenomenon will appear when the wing center of drag is above the wing. Adding winglets or making the wing polyhedral will have the effect of rotating the wing as speed increases. These wings will go from vastly increased AOA and stall to normal and back again in a rapid sequence which is frightening to say the least. The foamy structural integrity saves it from destruction. I have seen this same type of occilation on my 2m sailplane while trying to descend out of a horrific thermal. Tex.
Sabrejock is offline Find More Posts by Sabrejock
Reply With Quote
Old Apr 20, 2001, 08:24 PM
characters welcome!
Mark Wood's Avatar
United States, CA, Bear Valley Springs
Joined Feb 2000
26,446 Posts
Yup! The Dreaded Zagi Flap alright.
Happened to me with the same consequences. I had a couple of witnesses watching that had never seen an electric before. As it flip-flopped back to earth one guy said, "Whatinell was THAT???". Being somewhat shocked myself, I collected the scattered pieces muttering something about meaning to do something about a soft airframe and left.
Now you know why the 400X comes with a CF spar.

mw
Mark Wood is offline Find More Posts by Mark Wood
Reply With Quote
Old Apr 20, 2001, 08:31 PM
Registered User
Texas
Joined Aug 1999
5,110 Posts
I saw the exact same thing happen to Andy W's Zagi at DEAF last year when he was dared to take his Zagi to 500' and do a power dive straight down. I don't think that he ever found the battery.
dave_lilley is offline Find More Posts by dave_lilley
Reply With Quote
Old Apr 20, 2001, 08:46 PM
tic
thunderscreech
tic's Avatar
New Cumberland, PA. US
Joined Dec 2000
10,936 Posts
And I must listen to constant bantering about how "zagi's rule"?.... yeah, maybe a "wing in transit" light should be installed somewhere on the tx
tic is offline Find More Posts by tic
Reply With Quote
Old Apr 20, 2001, 09:03 PM
Motors beat engines!
Milwaukee Wisconsin, United States
Joined Feb 2001
4,564 Posts
Gee, a skyscooter would never behave that poorly. Course, a scooter is a REAL plane! LOL.
DeaninMilwaukee is offline Find More Posts by DeaninMilwaukee
Reply With Quote
Old Apr 20, 2001, 09:40 PM
Registered User
El Cajon, CA, USA
Joined Feb 2001
801 Posts
Ok guys....time to add some gas to this fire.....

How fast is the zagi going? (approx of course)

How fast can a sky scooter go?

Can a sky scooter hit a velocity in which this will happen?
Munch is offline Find More Posts by Munch
Reply With Quote
Old Apr 20, 2001, 10:01 PM
Registered User
United States, CA, Anaheim
Joined Aug 1999
1,297 Posts
Yah!! And besides that, sky scooters are ugly!
Gene is offline Find More Posts by Gene
Reply With Quote
Old Apr 20, 2001, 10:48 PM
RIP Ric
Andy W's Avatar
Marietta, GA
Joined Jun 1999
43,312 Posts
Duh..
As Dave said, been there, got the T-Shirt. The precise sequence of events was JIM BOURKE said "Hey Andy, what would happen if you go up 400' and then dive straight down and pull out at the last second?" - I made it down about 300' then it exploded. I never found that 8x800AR pack! I think it's in Kansas..
Sky Skooter would have to go a lot faster before that would happen - faster than any power system it could possible fly with, in fact!
The size of the wing
Andy W is offline Find More Posts by Andy W
Reply With Quote
Old Apr 20, 2001, 10:58 PM
Motors beat engines!
Milwaukee Wisconsin, United States
Joined Feb 2001
4,564 Posts
"The size of the wing"

So this is all about wing envy?
DeaninMilwaukee is offline Find More Posts by DeaninMilwaukee
Reply With Quote
Old Apr 20, 2001, 10:59 PM
Living electrically
West of Emporia Kansas
Joined Feb 2001
68 Posts
Ummmm..Andy: I have been comtemplating the 8x800 pack for my Zagi...Where in Kansas did you last see it??? jb
diode is offline Find More Posts by diode
Reply With Quote
Old Apr 20, 2001, 11:19 PM
RIP Ric
Andy W's Avatar
Marietta, GA
Joined Jun 1999
43,312 Posts
I last saw it in Dallas, heading that way at about terminal velocity (terminal for the Zagi, that is! )

Oops.. my post was truncated.. (ouch!).. I meant to say the Zagi wing is so large, yet relatively soft, oscillation forms quite easily.. that's what causes the "flap"..
..a
Andy W is offline Find More Posts by Andy W
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Sold Brand new,Never Opened. Speed 400 motor,30A ESC, 1800mah NIMH Battery, $ 37 Shipped wilsonbueno Aircraft - Electric - Power Systems (FS/W) 2 Mar 11, 2006 04:13 PM
ABX Tail mod... Plus ABX do not exceed speed.... Waldo19 Parkflyers 3 Oct 31, 2004 01:44 PM