Flying hangglider too fast! | Tony Marty
Вставка
- Опубліковано 27 лип 2019
- Flying with Atos VQ from Crap Sogn Gion, Laax Switzerland. The southwest take off is very flat, be sure to have enough headwind! After 2 hours of flying the clouds were getting too big. So I flew back to the take off and made a flyover.....(too fast)
Thanks to Urs for the video from the take off.
file from the flight: www.xcontest.org/switzerland/...
Music: Alan Walker - Spectre
Watch at: • Video - Спорт
The bungie that attaches the flaps to the keel need to be strengthened or replaced, it's that simple. When the string is released, the flaps should snap back to the keel. Your spoilers could use the same attention. I've been to 140+ kph, on a much older rigid, without experiencing flutter.
Whole wing flutter. Dangerous! Influenced by the elasticity/rigidity of the structure's materials and the mass/load distribution. Unavoidable, defines VNE. On control surfaces it can usually be mitigated by adding masses upstream of the hinge line. Can be dinamically unstable, leading to structural failure. You were lucky. Check/test the whole assembly for fatigue!
Looks more like control surface induced flutter as opposed 'whole wing' flutter. The aerodynamic forces exceeded the mechanical capability of the flap control cables to maintain a set position. Once the flaps started 'flapping', then a resonance set in that exacerbated it. Another contributor would be the insufficient torsional stiffness of the flap itself. You could try to stiffen the flap linkage to mitigate it, but because it is attached at the root end of the flap and the rest of the flap is unrestrained, any torsional weakness along the length of the flap would result in it 'flapping' anyway at some point. The nose angle of the camera clearly shows the flap being the primary contributor to the flutter. Note that the upper control surfaces could cause flutter too. Fly fast enough and the low pressure on top of the wing can be strong enough to overcome the spring tension and pull the spoilers up, then the apparent wind will push them down, then the low pressure will suck them out again and the cycle continues. That wasn't the case here, likely because the flaps were the weak link in this chain.
resonance is a dangerous phenomenon that can destroy the structure.
A tip : you can watch movies at flixzone. I've been using them for watching lots of of movies during the lockdown.
@Karter Quentin Yea, have been using Flixzone} for years myself =)
YIKES! There's your limit! lol
Looks like a form of flutter. Flutter of control surfaces on aircraft at high speed can lead to in-flight breakup/disaster! Suspect that the boom on the keel with a weight on the end of it (the camera) created a resonant mode that was triggered by the high speed flight. With the glider set up and resting only on the control bar, grab the end of the boom and push it up and down at the frequency you see in the video - you'll know that's the problem if you reproduce the entire wing flutter when you pushing up and down at the right frequency.
Thank you for your detailed explanation.
Totally agree
Vortex shedding?
VNE was exceded by almost 50%, guy found out why it was set at 90 km/h ;-)
Beautiful video, thanks.
Thank you!
All planes have a VNE (never exceed speed). I'd say you found yours.
Yes, that's true!
He exceeded it by a large margin and learned about Flutter. Luckily for him nothing broke. Or did it? I assume he's checked for delam after exceeding the structural load limit by such a huge margin. VNE for the VQ 90km/h
Very exciting view of the action. Strong wing.
Thank you for the nice comment.
Great video... but the music . Headache !!!
Pięknie :).Pozdrawiam.
Dziękuję!!
Front camera looks good to me, thank you so much.
Thank you for the nice comment.
Might be better to do a bit higher in case you need a bit more time for you to deploy your emergency chute. Landing would undoubtedly happen to the best of them especially with that flutter on your mind and not sure if the flare would even hold. Good job noticing it quickly and then making the right decision to get on the ground quickly, no need for style points in that situation. From what I seen very well done. To know that limit one must test that limit and very well prepared for it just maybe a bit higher would be better would you think or same height knowing the outcome?
MASHAALLAH khub valo video
Good the wings stayed on 😬😬😬
As an interested non flyer (yet), what is the flap that keeps popping up, on what appears to be the starboard wing only?
The flaps are attached to the base bar, so I can steer the glider.
👍
Maybe a hint of tension on the brakes would help? Too scary to repeat that though I'd imagine. Don't think I would care to try that again. Glad it ended well.
Thanks, i agree with you about the airbrakes. Maybe i try that one day! :-)
nope. sticking to the design VNE would help.
@@TheFlyingPlectrum Assuming he went past that.
@@garrykennedy5484 by 50%. VNE for that airframe is 90 km/h.
@@akkudakkupl OH dang. I didn't even check. Scaaaaary!!!!!
When did hang gliders get ailerons?
2:05 huge wing flutter! Keep watching thru the 3 minute mark!
Thank you Phil
user ddigglersbcglobal is spot on with his comment: This is the effect from the flaps not holding firm their reflexed position (on the Atos the flap's upflex (reflexed) position is helt up only by bungy, while down flap is pulled by rope).
Given the speed and thus aero forces big enough, the flaps will start initiate a flutter and the wing will just pick it up to a lesser extend and hopefully not go resonant.
I have observed this very same effect once while truck testing a tandem hang glider with too weak batten material on the inner (reflexed) batten sections. The section the gets pulled up from the flow around the reflex point, then drops and gets picked up again. The frequency is 5-10 HZ, very nasty. It was so virulent that the truck had to go hard on the brakes to not wreck the test rig itself.
The effect here seems still within bounds, though due to the fact of it happening inflight it was sure plenty scary for the pilot.
Good on you Tony, now you are a true test pilot :-)
Hoi Gerolf
Genau so habe ich das auch gesehen oder gespürt, dass die Schwingungen von den Bremsklappen ausgelöst wurden.
Erschrocken bin ich schon ein wenig ;-) , etwas Tempo wegnehmen und schon fliegt es wieder!
Gruss tony
@@tonymarty4500 I hatte da ja schon mehrmals am Boden draufgedrückt auf solche Klappen, und war immer erstaunt, daß diese Gummizüge dem Druck eigentlich so wenig Widerstand entgegensetzen. Dabei könnt man ja leicht doppelt so starke Gummis nehmen. Das "VG-System" mit dem Du die Flaps runterstellst hätt ja locker die Kraft es noch immer leicht einzustellen - eventuell braucht es noch eine Seil-Umlenkung mehr.
GREAT VIDEO, Wing has potential. Please sort out that shudder, Let us know. Music sucks!
Mark it on your AS indicator you test pilot you!!👍
2 Min 07 Sek: danke für die Video-Aufnahme = sehr interessant da ich dies bei einem Starrflügler noch nie vordemonstriert gekriegt hatte.... :-) // was ist die Vne (= max erlaubte Geschwindigkeit bei ruhigen Verhältnissen) gemäss Atos-Hersteller ? // ach ja: Deine Video gefallen mir meistens sehr. // Was die Musik betrifft: das ist vermutlich immer eine Geschmacksache jedes Einzelnen // viele Grüsse aus der Zentralschweiz
Danke Dani, ja die Vne liegt laut Hersteller bei 90 km/h! Wen man die Bremsklappen um 5 Grad anstellt treten die Vibrationen etwas später ein. (Habe ich gehört).
Aber ich glaub das probiere ich lieber nicht mehr aus. Bin mich halt noch vom Flex gewohnt, schnelle Überflüge zu machen...aber beim Flex gibt es immer mehr Bügeldruck und bei 120 -130 km ist auch Schluss.
Gruss Tony
Pull that bar back. You gotta push through that shit
:-D Right!!
Oops! Aber geile flug! :) Han denkt atos bringt nüüd us de rueh. Aber ebe xD
Salü Andri, jo, das han ich au denkt. Das sind anscheinend Eigeschwingige...mer söt de Atos jo sowieso nöd schneller als 90 km/h flüge. :-)
D'Musig macht auwes echli kabot, schad🥺
Ja, Musik ist halt Geschmacksache ;-) und immer etwas schwierig auszuwählen, es darf ja nur copyright freie Musik verwendet werden. Was meinst du zu der Musik im neuesten Film? ua-cam.com/video/fd7Zj6-gMTE/v-deo.html
Gruess Tony
Drop the music.
flutter.
what does "sagogn" mean?
Sagogn is the name from the little village I landet.
looks nice and natural! beautiful nature. does the village name, the word “sagogn” have some meaning, does it mean something? like “behind the woods”, “over the fields” or something similar?
Almost killed himself with wing flutter, didn't even know what it is... That airframe needs to be checked out, because flutter can cause cracking.
I'd say it's still a good landing... just not as stylish 👍🌤️
Thank's Massimo, yes, that's true!
Any landing you walk away from is a good one!.😎
Too bad youtube forces you to use music that chases away viewers.
Nice Clip but real crap music.