Suggested opening direction for hop'n'pop(subterminal)?

[phoenixlpr 0]

Is there any? It has happend with me some months ago:

I was leaving the plane got some delay,watching the plane fly away and going against the relative wind in a kindda delta position and popped my PC. My canopy was about to open when a saw the next jumper flying against, but over me. He was flying over me in 15-20m meters. I felt it was a close call. Any ideas?

Edit: subterminal added

[AggieDave 6]

If I'm following people out for a clear and pull or a hop-n-pop I'll face into the relative wind head up (facing the front of the AC). If I'm first out or there is a significant delay involved between the previous jumper and myself, I tend to dive the relative wind and ride the opening down the hill (facing the tail of the AC). On occasion I'll do the flip and throw PC during the flip thing, but that puts me back facing the tail.

Its easy to get too close to each other during clear and pulls or hop&pops, but its also easy to wait a LONG time and screw up the spot for those behind you or delay the rest of the load from continuing their climb to altitude. At anypoint though, its just like deployment at the end of a group skydive, you have to be aware of those around you and ready to get on your rears/toggles to fly around/away from others.

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[dragon2 2]

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Is there any? It has happend with me some months ago:

I was leaving the plane got some delay,watching the plane fly away and going against the relative wind in a kindda delta position and popped my PC. My canopy was about to open when a saw the next jumper flying against, but over me. He was flying over me in 15-20m meters. I felt it was a close call. Any ideas?

If you take a delay, it's not really a hopnpop. But the other jumper should have given you good separation, and not fly backwards over jump run. However an off heading opening can always happen, therefore the separation is important.

ciel bleu,
Saskia

[phoenixlpr 0]

Ok. Low altitude (~1000m) and subterminal jump where multiple jumpers in the same line.

[Reginald 0]

It's not an opening direction issue it's a separation issue.

"We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP

[Anvilbrother 0]

Does it matter which way you face the relative wind for a faster sub terminal opening? I.E. into the wind the canopy will open faster b/c the wind is rushing into the nose of the canopy. If you exit towards the tail a slower opening due to the wind blowing over the tail of the opening canopy.

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[billvon 2,991]

>Is there any?

Facing forward. That way you can see the next guy to exit. The guy who gets you is the guy you don't see.

[ryoder 1,590]

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Does it matter which way you face the relative wind for a faster sub terminal opening? I.E. into the wind the canopy will open faster b/c the wind is rushing into the nose of the canopy. If you exit towards the tail a slower opening due to the wind blowing over the tail of the opening canopy.

The canopy deploys directly downwind of your body with respect to the relative wind. It is irrelevant which way you happen to be facing.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[mjosparky 4]

On a sub-terminal opening, face the relative wind. That is facing the aircraft, head up. If you dive out, head down, during deployment the relative wind can take your P/C and blow it over the nose of your canopy. It can then get tangled with the "A" lines.

And before someone says it won’t reach, how many people know how long their bridle is and what is the distance from the bridle attachment point of their canopy to the nose?
Without checking!

Sparky

My idea of a fair fight is clubbing baby seals

[Anvilbrother 0]

It will reach I have it happen once and it stayed until i landed, and the second time after I released the brakes it flipped back over and started trailing me again.

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[phoenixlpr 0]

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On a sub-terminal opening, face the relative wind. That is facing the aircraft, head up. If you dive out, head down, during deployment the relative wind can take your P/C and blow it over the nose of your canopy. It can then get tangled with the "A" lines.

How come? IMO the canopy is always infalting against the (relative) wind.

[mark 107]

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On a sub-terminal opening, face the relative wind. That is facing the aircraft, head up. If you dive out, head down, during deployment the relative wind can take your P/C and blow it over the nose of your canopy.

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(I)nto the wind the canopy will open faster b/c the wind is rushing into the nose of the canopy. If you exit towards the tail a slower opening due to the wind blowing over the tail of the opening canopy.

Bill Von --

Thanks for the video proof that the 45-degree angle method doesn't work. Now we have this variant. What education and proof technique would you recommend?

Mark

[billvon 2,991]

>What education and proof technique would you recommend?

Doesn't matter. No one is going to get hurt if they think they have to face into the wind during a hop and pop. Heck, it's a useful belief, like the belief that the plane will climb faster if the CG is forward. It generally doesn't, but it's a good way to get people to keep the CG forward.

[phoenixlpr 0]

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Heck, it's a useful belief, like the belief that the plane will climb faster if the CG is forward. It generally doesn't, but it's a good way to get people to keep the CG forward.

I've seen some example where the pilot had some problem is climbing to altitude, because some guys were laying in the tail section of a turbine 207 and it was back to normal when they did move their ass as front they could.

[FrogNog 1]

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On a sub-terminal opening, face the relative wind. That is facing the aircraft, head up. If you dive out, head down, during deployment the relative wind can take your P/C and blow it over the nose of your canopy. It can then get tangled with the "A" lines.

How come? IMO the canopy is always infalting against the (relative) wind.

In any deployment there are two forces that could act on system components: aerodynamic and gravity. When we are falling straight down these are in-line with each other. When we deploy while tracking or in a hop-and-pop while facing the relative wind, head-up, then the acute angle between them is toward the rear of the canopy.

This may be important because at first the major force on determining where a PC goes is aerodynamic. Once the airspeed decreases, or the airspeed decreases and the PC is collapsed by its kill line, gravity will play a larger role in determining where the PC goes.

If "down" in gravity terms is toward the front of the canopy, it is possible that when the canopy starts inflating and the PC finds itself in an "air shadow", the PC could fall toward the front of the canopy and slip off. At that point it might find itself out of the "air shadow" and get blown back under the canopy.

For systems that deploy with spring-loaded pilot chutes, the weight of the PC is significant and periodically leads to these sorts of weirdnesses. And the randomness of every deployment means weird stuff happens in various directions.

Another interesting issue is where the jumper's body is relative to the canopy when the relative wind and gravity are in different places. I believe this leads to a fun "swing forward" effect when deploying on a hop-and-pop with the belly into the relative wind but head toward Earth. I'll try to keep an eye on my PC when I do this.

-=-=-=-=-
Pull.

[FrogNog 1]

It's interesting to note that if the angle described between the relative wind and gravity represents the most likely place for the PC to travel during canopy inflation, and if we prefer the PC to travel backward on the canopy vs. any other direction, then technically opening in a track should be less likely to allow the PC to wrap around the front of the canopy, which could be called "safer". Weird.

I'm not really worried about where my PC goes after inflation, though. It'll either get into trouble or it won't. (This sort of thing does make me happy about reserve freebags, though.)

-=-=-=-=-
Pull.

[FrogNog 1]

Regarding the real problem the poster asked about, separation:

varying delays can have a lot of difference for separation. I try to ensure on my loads the longest delays go first. I also try to ensure the highest wingloadings go first, too. Sometimes this means lightly-loaded terminal hop-and-pop lovers with nevr-spin canopies (knock on wood) like me have to do things differently to be compatible with heavily-loaded folk who want maximum canopy time and want lots of altitude in case they spin up.
But I'm talking about little 182 / 206 loads here. If people are hop-and-popping out of big planes, you'll either have to organize your loads a lot harder or come up with some other plan.

-=-=-=-=-
Pull.

[ryoder 1,590]

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Heck, it's a useful belief, like the belief that the plane will climb faster if the CG is forward. It generally doesn't, but it's a good way to get people to keep the CG forward.

I've seen some example where the pilot had some problem is climbing to altitude, because some guys were laying in the tail section of a turbine 207 and it was back to normal when they did move their ass as front they could.

More likely, the pilot was making an excuse to get the jumpers to move to put the CG back where it should be. In general, any a/c that has manually actuated controls, is deliberately designed nose-heavy. During level flight, the wing is generating upward lift, and the tail is generating downward "lift". Since the tail is pushing downward, the wing must generate not only enough lift to support the plane, but additional lift to counteract the downward force on the tail. Moving weight toward the tail will lessen the need for downward aerodynamic force, and in fact make the plane fly more efficiently. BUT...

...the reason the a/c is designed nose-heavy is to cause the nose will drop in a stall, ensuring the a/c can recover from a stall or a spin. Operating with the CG aft of where it was designed to be means the a/c may enter an unrecoverable stall or spin. In a spin, forces may easily be so high that a jumper couldn't exit even if he was located right next to the door.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[mjosparky 4]

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How come? IMO the canopy is always infalting against the (relative) wind.

Do you deploy on your back? If not, how come? Think about it.

Sparky

My idea of a fair fight is clubbing baby seals

[phoenixlpr 0]

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Do you deploy on your back? If not, how come? Think about it. Crazy

???

If you open from terminal, your canopy opens vertically.

Have you seen a high speed static line? Canopy opens almost horizontally.

[davelepka 4]

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If you open from terminal, your canopy opens vertically.

Have you seen a high speed static line? Canopy opens almost horizontally.

This whole discussion is retarded. Wind this, gravity that, the angle of your dangle.

Your canopy will open downwind of you in the relative wind. Period. The PC will be downwind of the canopy in the relative wind. Period.

If your canopy should stall, or surge on opening, and generates relative wind toward the nose, you may get your PC up there.

You could launch yourself skyward with a giant catapult, and dump on the way up, and your canopy will open underneath you (what happens after inflation is another story).

[Scrumpot 1]

Can't relatively decent separation be gained even with a rapid succession of hop-n-pop's occurring, by simply:

1. Having a "plan" and that ALL the exits are going to be TRUE HOP-N-POPS (that 3rd guy out taking a delay instead NOT throwing a wrench into those works! )? ...ie: head high, "forward facing" CLEAR & PULLS?

2. 1st guy out upon deployment turns right of line of flight, 2nd guy left (45-90' MAX) and evenly alternating from there?

3. KNOW your "assignments" then, go, go, go, go, go...

I could envision under such (even in an "emergency exit" scenario calling for such) being able actually to put people out in a rather rapid succession, -no?

coitus non circum - Moab Stone

[billvon 2,991]

> Can't relatively decent separation be gained even with a rapid succession of hop-n-pop's . . .

Yes. Even a short delay is generally sufficient; one second between jumpers ends up as about 160 feet of separation, which is enough if you keep the next jumper in sight and open immediately.

[mjosparky 4]

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Do you deploy on your back? If not, how come? Think about it. Crazy

???

If you open from terminal, your canopy opens vertically.

Have you seen a high speed static line? Canopy opens almost horizontally.

(speaking real slow) If the relative wind is from your back during deployment the PC will blow forward or toward the nose of the canopy.

Yes I have seen static line deployment up to 180 KEAS. The one thing I noticed was there was no pilot chute. As I said in my first post "think about it". If it is over your head, forget it and exit and deploy any way you want.

You asked a question, got an answer, end of discussion.

Sparky

My idea of a fair fight is clubbing baby seals

[phoenixlpr 0]

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You asked a question, got an answer, end of discussion.

AYE, Sir!