Mystery of flat spin

[phoenixlpr 0]

How can you get into flat spin?

[hjumper33 0]

backfly, cock one arm wing up, the other down behind you, and extend your leg wing maximally to tip head down a little. That usually works for about 2 rotations a second for me.

[phoenixlpr 0]

How would that be a flat spin? It sounds like a head down spiral.

[pattersd 0]

Its a "Flat Spin" because the wingsuiters definition of a flat spin seems to be any uncontrolled tumble or really fast rotation. Ignore any other definition of flat spin that might have been in use in general aviation for nearly a hundred years that you might have learned from numerous credible sources.

[lurch 0]

I can sort of relate to the sarcasm here... Had a guy once start enthusiastically telling me he got into a flat spin under canopy. This just made him sound like he had no idea what he was talking about, I told him thats a wingsuit thing and whatever rotation he was doing, it wasn't a "flat spin" if he had a canopy over his head. Misuse of technical terms bugs me.
To the original poster:
A flat spin is rotation around your center, as if you were belly down on a creeper and someone spun you. Its hard to get out of because in a true flat spin all your control surfaces are being hit with wind at 90 degrees to normal airflow and almost none of it is flowing in the usual way from head to tail so none of the usual control inputs work. Like trying to fly a plane sideways with the left wingtip leading like the nose is supposed to, or trying to steer a skidding car. Car can't steer at all, if the steering wheel is centered and its skidding SO totally sideways that the tires aren't even turning.
To deliberately get into one, try doing a barrel roll while keeping your tail completely open, and your armwings as well, so you stay head-high throughout the roll. If it doesn't spin you during the roll to your back, the second half of the roll, about at the 270 degree mark when the control inputs are reversed both upside down and backwards, will. Because thats the place where the control inputs are going to be least familiar and and you're not likely to have an instinctive muscle memory for the airflow at that time. I did that once by accident while trying for an under-the-flock video shot, and when my tail caught air at a 45 degree angle it applied a strong sideways input, spun me like flicking one end of a pencil on a table with your finger. WEEEE! My head and tail abruptly switched places and just kept going. I didn't pitch over head-down...stayed level, but head and tail kept switching places every half a second or so. Took me a couple seconds to get it stopped and half the remaining flight time to catch up to the flock after.
Fly long enough and eventually flat spins just won't happen to you anymore, if they ever even did, because anytime you even get close to getting into one you'll instinctively compensate with a preventive/recovery move, counterinput. Cocking your tail in the opposite direction, for example, or digging in with the trailing armwing to act as one-sided brakes. Its all about the ninja tricks and muscle memory... build a big enough library of em and get so familiar with weird flight modes that you use the ninja tricks without even thinking about it and you'll never spin unless you intend to. No mystery in flat spins, once you understand exactly what is happening and why.

Live and learn... or die, and teach by example.

[phoenixlpr 0]

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To deliberately get into one, try doing a barrel roll while keeping your tail completely open, and your armwings as well, so you stay head-high throughout the roll.

I did barel rolls with leg wing open. It gave me a diving roll only. How can I stay head high if I have a full leg wing flying?

I have found this.

It looks like an Mach1 or SM1 on the video flown on the back with narrow leg wings, than spin start with asymmetric leg position.

[mccordia 73]

http://www.flylikebrick.com/playmovie.php?id=24

This one also has a nice flatspin about halfway in, someone trying some aerobatic stuff and not closing the legwing properly.

A transition to the back, combined with the initiation of a 180 degree turn seems to 'sorta' put you in a chance-zone in becoming a human properblade..

I know Perry did some experimenting with that stuff as well..

JC
FlyLikeBrick
I'm an Athlete?

[VectorBoy 0]

That looks like a downward augering spiral not an unrecoverable flat spin.

[mccordia 73]

I think in most cases, thats what people mean when talking flat-spin.
If its really 100% what a flatspin entitles in an airplane. I dont know..

Call it whatever you will. But on suits with low wing attachments (big armwings) and a huge legwing, the risk of getting into these, and having severe recovery issues...its there..

JC
FlyLikeBrick
I'm an Athlete?

[phoenixlpr 0]

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That looks like a downward augering spiral not an unrecoverable flat spin.

He recovered so it was not unrecoverable.

[lurch 0]

Like I said, arm wings open wide. The conditions necessary to produce the effect are
1: being head-high or at least flat and level
2: asymmetrical tailwing applying a strong sideways force to just the lower half of your body

This is why real flatspins are fairly rare and most spins are diving spirals. Usually with tailwing wide in the middle of a roll, you don't have enough wing open up top to stay level and be spun on your center axis, so most such maneuvers immediately turn into the diving roll you spoke of. This is also why flatspins tend to occur during acrobatic maneuvers. Lets say you just did a steep headdown dive and are now flaring out of it. As you flare out of it your head comes up and feet go down, your "rotation" is that of an aircraft lifting the nose to take off. Pitching up. Once the pitching up is underway, you have enough momentum to stay head high even if you fold an armwing or two for a second. And if you happen to get just your feet kicked sideways at -just- that particular moment, BAM, you spin out.

Cops use this in pursuits all the time, bumping a car's rear end sideways, its called a PIT maneuver. Best police chase I ever saw, was a guy in a Mustang who knew what he was doing. The cops PITted him, and he anticipated it, steered with it to catch the car on the far side of the spin, did a neat 360 at highway speed. The spin stopped on-heading with the car facing forward and the guy kept right on going. This is also why you seldom see the more experienced pilots get knocked spinning. They recover inside of one rotation even when taken out by someone that just flew into their burble and landed on them.

Around my home DZ we've got enough highly experienced pilots to play games with taking each other out on purpose when we're in a rough-and-tumble sort of flying mood. Reed's still trying to figure out the angle he's gonna have to tackle me from to bag me, and the last time I tried to take out Justin with an unexpected scary roll, he took the surprise shock loading to one wing without a wobble, I lost my grip on his wing and the only thing I took out was myself, to everyone's amusement.

Do enough acro so you flip and spin without getting disoriented and the much-feared specter of the Flat Spin just sort of vanishes like an illusion. It just won't happen to you because you stopped it before it started without even having to think about it. If you've already built up enough experience to recover automatically, it may -never- happen to you, and since you compensate automatically, it can be hard to try to get into one deliberately. Its like trying to deliberately lose your balance and fall over-once you've got the reflexive recovery instinct hardwired to the muscle memory of the act, its difficult -not- to stop the spin in half a twist.
-B

Live and learn... or die, and teach by example.

[SuperGirl 0]

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I have found this.

is that JSho over Zhills in 2007?
teeheee