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Steering a 2 out bi-plane

 

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DiverMike  (C 40024)

Nov 10, 2011, 1:16 PM
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Steering a 2 out bi-plane Can't Post

A separate post shows a roof landing with two out and some people indicate the skydiver should have steered away from the roof. Makes sense. I have never had a two out, so I am asking those who have how much is the steering impeded by the additional chute? Can you turn too much with the dominant canopy and create a wrap? Or does the biplane respond to inputs relatively normally? I'd hate to be asking these question when I am getting ready to land on a house.


wildcard451  (D License)

Nov 10, 2011, 1:24 PM
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Re: [DiverMike] Steering a 2 out bi-plane [In reply to] Can't Post

From 650ish with the toggles already out I was able to bring about a 180deg turn slowly to land in an open field. Could have likely stood it up, but PLF'd anyways. It flew like a big ass boat.

Sab2 170
I think a Raven 181. I don't remember the reserve exactly.


dragon2  (D 101989)

Nov 10, 2011, 1:30 PM
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Re: [DiverMike] Steering a 2 out bi-plane [In reply to] Can't Post

Steering in a 2out situation should be done gradually and only as necessary. Ie, avoiding that roof.

We have some video we show at our FJC that shows an intentional side-by-side where the jumper can steer quite a lot with the reserve canopy following the main around. OTOH I had a 2out biplane that after 1000ft downplaned on me all by itself - I did have the brakes of the main unstowed so it was flying a bit faster than the reserve, but I wasn't steering at the time. YMMV. Just do not flare or pump the brakes.


PiLFy  (A License)

Nov 10, 2011, 1:41 PM
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Re: [DiverMike] Steering a 2 out bi-plane [In reply to] Can't Post

An experienced jumper posted to unstow the brakes on the main. I was taught not to unstow either brakes. Both of them being in 1/2 brakes helps them fly/stay together. Or, so I was told. Why would I want to unstow the brakes? I was taught to steer by using the rear risers of the dominant canopy.


pchapman  (D 1014)

Nov 10, 2011, 3:27 PM
Post #5 of 46 (2567 views)
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Re: [DiverMike] Steering a 2 out bi-plane [In reply to] Can't Post

For reference, the SIM says:
Quote:
3. Stable biplane
a. Unstow the brakes on the front canopy and recover gently to full flight.
b. Leave the brakes stowed on the rear canopy.
c. Steer the front canopy only as necessary to maneuver for a safe landing.
d. Use minimal control input as necessary for landing.
e. Perform a parachute landing fall.

FWIW, the CSPA says to leave the brakes stowed.

I'm interested in the whole question too, although my current thoughts are to usually leave the brakes on the front canopy stowed.

The answer for me would vary if I think one canopy is a lot faster than another -- e.g., Fast main infront of slow reserve, keep brakes set. But if fast main behind slow reserve, maybe pop the front canopy's brakes.


(This post was edited by pchapman on Nov 10, 2011, 3:28 PM)


Krip  (Student)

Nov 10, 2011, 3:44 PM
Post #6 of 46 (2554 views)
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Re: [wildcard451] Steering a 2 out bi-plane [In reply to] Can't Post

In reply to:
From 650ish with the toggles already out I was able to bring about a 180deg turn slowly to land in an open field. Could have likely stood it up, but PLF'd anyways. It flew like a big ass boat.

Sab2 170
I think a Raven 181. I don't remember the reserve exactly.

We had a biplane at approx 1500' with a 7 cell cruiselight 220 sq ft, and a 5 cell swift reserve.

Winds were slow and steady, 3 gradual 90 degree turns downwind base and final so we could land close enough, with a easy stand up.

K-RIP


monkycndo  (D License)

Nov 10, 2011, 5:04 PM
Post #7 of 46 (2506 views)
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Re: [DiverMike] Steering a 2 out bi-plane [In reply to] Can't Post

I had two out and had main brakes unstowed before I realized my reserve was out. Sabre 170 and PDR 176 in a biplane, steered very gently having to make a 270 to get to a landing area. If I had a choice, would have kept brakes stowed.


iowa  (D 16855)

Nov 10, 2011, 5:06 PM
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Re: [Krip] Steering a 2 out bi-plane [In reply to] Can't Post

This may not click, but, good info.

Clicky: http://performancedesigns.com/docs/dualsq.pdf

There is also other testing on two outs somewhere on the net.


Krip  (Student)

Nov 10, 2011, 5:20 PM
Post #9 of 46 (2498 views)
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Re: [iowa] Steering a 2 out bi-plane [In reply to] Can't Post

In reply to:
This may not click, but, good info.

Clicky: http://performancedesigns.com/docs/dualsq.pdf

There is also other testing on two outs somewhere on the net.

Made it click for you I hopeWink

The golden knights made some test jumps about how to handle a two out situation, USPA ST&A may have a copy, or Like you said it it's some place else on the net.

K-RIP


sundevil777  (D License)

Nov 10, 2011, 7:44 PM
Post #10 of 46 (2449 views)
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Re: [DiverMike] Steering a 2 out bi-plane [In reply to] Can't Post

Usually the reserve is behind and slightly lower than the main. This is similar to what a CRW biplane (2 separate people) would be. Even if unstowing the brakes of the main is bad in that it causes it to fly much faster than the reserve, there is no reason that you can't bring it back to the stowed condition by holding some brakes manually. It really should, theoretically, steer much like a biplane, which can be done with gentle input from the top canopy alone. A biplane is best behaved when both canopies are flying similarly, so preventing the main from going too fast would be wise and as I said above can be done even if the brakes have been unstowed. I would still flare about half way at the end, with the main. The reserve would be pushing on the rear of it, so maybe a full flare would not be a great idea, but I'd give it something of a flare. Others will disagree.


Baksteen  (C 708753)

Nov 11, 2011, 4:46 AM
Post #11 of 46 (2383 views)
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Re: [sundevil777] Steering a 2 out bi-plane [In reply to] Can't Post

I teach students to leave the brakes stowed and to refrain from flaring, both for Biplane and Side by side configurations. Downplanes are to be cutaway immediately, irregardless of altitude.

They've got 500 square feet of fabric above their heads - why risk upsetting the stable configuration they are flying by flaring or by releasing the toggles?

Use very small rear-riser inputs to turn into the wind and to prepare for a PLF.


NovaTTT  (D 17887)

Nov 11, 2011, 1:10 PM
Post #12 of 46 (2286 views)
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Re: [Krip] Steering a 2 out bi-plane [In reply to] Can't Post

In reply to:
The golden knights made some test jumps about how to handle a two out situation

Here ya go
Attachments: PIA Two Out Report.pdf (27.8 KB)


pchapman  (D 1014)

Nov 11, 2011, 1:30 PM
Post #13 of 46 (2279 views)
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Re: [NovaTTT] Steering a 2 out bi-plane [In reply to] Can't Post

Thanks for posting the PIA dual square report here.

The report does say to leave the brakes set on the rear canopy of a biplane, and they back that up with statements about tests where for most but not all canopy combinations, they flew better with the rear canopy in brakes.

But for the front canopy, they suggest flying that in toggles, yet don't provide data or statements to back that up. They don't specifically mention flying the front canopy with the brakes in hand versus with the brakes set.

So the PIA study unfortunately doesn't provide any evidence about what to do with the front canopy, but seems to just assume that one would fly it with brakes unstowed.


(As for whether to flare or not for landing, they say not to flare, but say that part of the reason is that students may flare too high. We always have to distinguish between what the 'ideal' action is, that we as experienced jumpers may choose to do, versus the 'simplified' action that may be best to teach students.)


popsjumper  (D 999999999)

Nov 11, 2011, 4:21 PM
Post #14 of 46 (2242 views)
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Re: [pchapman] Steering a 2 out bi-plane [In reply to] Can't Post

In reply to:
Thanks for posting the PIA dual square report here.

The report does say to leave the brakes set on the rear canopy of a biplane, and they back that up with statements about tests where for most but not all canopy combinations, they flew better with the rear canopy in brakes.

But for the front canopy, they suggest flying that in toggles, yet don't provide data or statements to back that up. They don't specifically mention flying the front canopy with the brakes in hand versus with the brakes set.

So the PIA study unfortunately doesn't provide any evidence about what to do with the front canopy, but seems to just assume that one would fly it with brakes unstowed.

It specifically says flying canopy with the toggles. That tells me that, yes, use the toggles t fly the damn thing.


pchapman  (D 1014)

Nov 11, 2011, 4:34 PM
Post #15 of 46 (2233 views)
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Re: [popsjumper] Steering a 2 out bi-plane [In reply to] Can't Post

Let me try to be clearer about the PIA study:

They do indeed say to fly the front canopy with brakes unstowed, but never say WHY they conclude that. They never mention even trying to fly it with brakes stowed. They never claim any data from their test jumps to support the conclusion.

That's different than in the case of the rear canopy, where they report on trying it both ways, and from that data, come up with a conclusion.


DiverMike  (C 40024)

Nov 11, 2011, 4:55 PM
Post #16 of 46 (2228 views)
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Re: [NovaTTT] Steering a 2 out bi-plane [In reply to] Can't Post

Thanks for the link to the report. It makes sense. Do as little as possible to prevent making a bad situation worse.

If I am dumb enough some day to have a two out (and some of my instructors think I am) I will know to make as few minor corrections as possible.


riggerrob  (D 14840)

Nov 12, 2011, 8:16 AM
Post #17 of 46 (2167 views)
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Re: [pchapman] Steering a 2 out bi-plane [In reply to] Can't Post

In reply to:
... PIA study:

They do indeed say to fly the front canopy with brakes unstowed, but never say WHY they conclude ....

........................................................................

You are over-thinking the problem.

Look at who the report comes from: the United States Army.

Enlisted men (the Golden Knights who did the jumps) are discouraged from questioning WHY orders were given.
Officers ordered enlisted men to test several configurations and the enlisted men reported which configuration flew the best.
Period!
End of test program!
Write report!
Now let's get on with our next task.


(This post was edited by riggerrob on Nov 12, 2011, 8:18 AM)


riggerrob  (D 14840)

Nov 12, 2011, 8:37 AM
Post #18 of 46 (2157 views)
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Re: [pchapman] Steering a 2 out bi-plane [In reply to] Can't Post

I have only made enough mistakes to survive one two-out.
The canopies were a Manta 290 main and a Tempo250 reserve.
I had already un-stowed the toggles on the main before the AAD activiated the reserve.
I never touched any of the reserve controls.
With minor steering inputs - on the main - the reserve followed gently through gentle turns.
As soon as I applied more than 1/4 toggle input - on one side of the main - the two canopies started to diverge. Fear of a down-plane told me to quit making large control inputs.
For the rest of the canopy(s) ride, I only made very gentle (less than 1/4 deflection on one main toggle).
I did not flare, just slid out the landing on wet grass (read swamp). Rate of descent was so slow that I did not need to PLF.
If I had to do it all over again, I would not bother to un-stow the main steering toggles ... and just steer gently with main risers.

Which brings us to the (dumbed-down) version that we teach to first jump students. Since we have only talked about controlling canopies with toggles, it follows logically to tell FJC students to steer the main with toggles ... very gentle toggle inputs.

IOW If the two canopies are playing well together, then less you mess with them the better.


SwampGod  (D 27345)

Nov 12, 2011, 9:49 AM
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Re: [DiverMike] Steering a 2 out bi-plane [In reply to] Can't Post

With regards to using to using toggles or rear risers, I try to simplify it for students and fun jumpers alike with the, "If it ain't broke, don't fix it," approach.

That is, your canopies will most likely open with the brakes stowed. If they are playing nice together, there's nothing to fix, so go ahead and simply use the rear risers gently to steer. If they're fighting, it may be time to use the brakes on the dominant canopy, as it wouldn't make sense to try to push a dominant canopy around with a wimpy one.

This logical approach seems to... stick better than getting students to memorize a series of procedures.

-eli


Krip  (Student)

Nov 12, 2011, 3:27 PM
Post #20 of 46 (2068 views)
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Re: [pchapman] Steering a 2 out bi-plane [In reply to] Can't Post

In reply to:
Let me try to be clearer about the PIA study:

They do indeed say to fly the front canopy with brakes unstowed, but never say WHY they conclude that. They never mention even trying to fly it with brakes stowed. They never claim any data from their test jumps to support the conclusion.

That's different than in the case of the rear canopy, where they report on trying it both ways, and from that data, come up with a conclusion.

That PIA/GK atudy/report has been around for a while. Maybe even before steering with the rears became common knowledge. I know it was pre canopy coaching.

I;m not a instuctor rigger or coach, I just used the KISS principal.Shocked

I used my toggles because thats the only thing I knew, I did a stand up landing becuase I didn't want to fall down and then stand back up again.Wink

As you were, or carry on, and continue with your debateBlush

K-RIP


popsjumper  (D 999999999)

Nov 12, 2011, 5:35 PM
Post #21 of 46 (2042 views)
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Re: [riggerrob] Steering a 2 out bi-plane [In reply to] Can't Post

In reply to:
I had already un-stowed the toggles on the main before the AAD activiated the reserve.
I never touched any of the reserve controls.
With minor steering inputs - on the main - the reserve followed gently through gentle turns.
.
.
.
If I had to do it all over again, I would not bother to un-stow the main steering toggles ... and just steer gently with main risers.

So, using the toggles worked well for you. Why change what works?

To everyone:

Some guys in here are trying to re-invent the wheel.

Everybody has an opinion...away from what works.

You guys telling students to do something against what the USPA condones may just be facing a plaintiffs attorney explaining yourself on why.

Be careful with that. Don't let ego cloud your sensibilities.


JohnMitchell  (D 6462)

Nov 12, 2011, 7:43 PM
Post #22 of 46 (2008 views)
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Re: [PiLFy] Steering a 2 out bi-plane [In reply to] Can't Post

In reply to:
An experienced jumper posted to unstow the brakes on the main. I was taught not to unstow either brakes. Both of them being in 1/2 brakes helps them fly/stay together. Or, so I was told. Why would I want to unstow the brakes? I was taught to steer by using the rear risers of the dominant canopy.
We were flying biplane stacks long before square reserves. You can easily make a gentle turn and the back canopy will follow, like a trailer following a truck. I've even spiraled canopy stacks. If it does downplane, chop the main.


3. Stable biplane
.....................
d. Use minimal control input as necessary for landing.
........................


I disagree with "minimal input" for landing. I say do a normal, symmetrical flare. Why wouldn't you?

Most of these techniques for 2 out were developed and tested in the 90's by the Golden Knights CRW team. I learned most of this stuff directly from one of my friends who was one of the test jumpers.
Attachments: stack dead center.jpg (54.4 KB)
  two stack.jpg (24.6 KB)


drewcarp

Nov 12, 2011, 8:58 PM
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Re: [riggerrob] Steering a 2 out bi-plane [In reply to] Can't Post

Question...Will a 2 out with lightly loaded canopies respond to harness input?

It seems like harness input would steer both canopies much more equally than pulling risers or toggles on just one.

If its stable and you have a place to land that doesn't need sharp turns I'd say don't mess with it by releasing the toggles. If you overcompensated and yanked the breaks that could send the back canopy into the front one which sounds like bad juju. But guess I do see how you could maneuver faster with the front toggles if you needed to and were all smooth and skilled and shit, which I'm not.

Good discussion.


(This post was edited by drewcarp on Nov 12, 2011, 9:00 PM)


riggerrob  (D 14840)

Nov 13, 2011, 10:55 AM
Post #24 of 46 (1904 views)
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Re: [drewcarp] Steering a 2 out bi-plane [In reply to] Can't Post

"
In reply to:
Question...Will a 2 out with lightly loaded canopies respond to harness input? ...
"

.........................................................................

Ridiculously slowly.
So slowly that you may not notice the difference between a "built-in" turn and a harness input" turn.


riggerrob  (D 14840)

Nov 13, 2011, 10:59 AM
Post #25 of 46 (1901 views)
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Re: [JohnMitchell] Steering a 2 out bi-plane [In reply to] Can't Post

"
In reply to:
...
d. Use minimal control input as necessary for landing.
........................

I disagree with "minimal input" for landing. I say do a normal, symmetrical flare. Why wouldn't you? ...
"

.....................................................................

Because with 500 to 600 square feet of nylon (typical student canopies) overhead, you are descending so slowly that flaring does not make a difference.
The risk is that a student will flare too high and mess with something that is working.

IOW If it is descending slowly enough to walk away from the landing ... why mes with success?


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