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

[kelpdiver 2]

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

so how serious a concern is it?

I did both the 5.5 trial and the 3.5 A checkoff HnPs doing a rear facing dive out of a 182. On the low one I simulated an urgent GET OUT and just flung myself out into a forward loop, arch and pull.

Am I better off changing this to a rotate 180 degrees to be head up? (A forward facing exit would take time out of these tiny planes)

[billvon 2,991]

>If the relative wind is from your back during deployment the PC will
> blow forward or toward the nose of the canopy.

?? No it won't. The PC will go in the direction of the relative wind. It will pull the canopy. The canopy will go in the direction of the relative wind too. They will both stay in line until the canopy inflates enough to 'burble' the PC, at which point it will start bopping around on the top of the canopy, its job done.

Sometimes, especially if there's a spring in the PC, it will manage to bop over the front or rear edge of the canopy, occasionally causing trouble. Facing away from the wind won't cause it; facing into the wind won't prevent it.

[phoenixlpr 0]

It so nice to see you so agreed on that.

[JohnMitchell 16]

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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.

It sounds like you kinda tracked back at him, using your delta. What was the time separation between you?

[phoenixlpr 0]

I don't know/Ican't remember.

[pilotdave 0]

I might have misread the situation, but here's something that has happened to me that sounds similar.

Plane went up to 14000, couldn't find a hole over the DZ, so we went back down to 4000 or so for "hop n' pops"... but from 4000, you can still do a 10 second delay or more if you want to. Different delays, exit order determined by seating in the plane (not the other way around), etc can lead to lots of... ummm... fun.

So my turn comes. I waited about 3 seconds and exited, pulling right out the door. Guy before me took about a 5 second delay. My canopy opens much slower than his, especially subterminal. So there I was, snivelling, looking straight down at his canopy as it opened. Mine ended up opening just fine with plenty of (vertical) separation. But it was definitely too close for comfort.

I THINK what happened is just that he got a lot more forward throw than I did, since he took a delay and I didn't. That put me almost right over top of him, pulling slightly before him. And since his canopy (PD 9-cell) didn't snivel much and mine (sabre2) snivelled a lot, I was coming almost straight down toward his open canopy.

Could something like that have happened here?

Dave

[Scrumpot 1]

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Facing away from the wind won't cause it;

Maybe with a non-collapsible though, it might??
At that point where the main has mostly inflated, but not "found" its full forward momentum into the relative wind? ...I dunno. Just trying to picture this and wondering.

Interesting you mention spring-loaded/launched main PC's. Seems I remember a fairly "regular" occurance of PC's over the nose back in the days of using those, and nearly none now with hand-deploys. A correlation there, or just coincidence?

coitus non circum - Moab Stone

[billvon 2,991]

>A correlation there, or just coincidence?

There was definitely a correlation. The additional mass meant that the PC responded more to deceleration (i.e. the canopy's deceleration from 120mph) and less to drag (which tended to keep it above the canopy.)

[mjosparky 4]

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?? No it won't.

I have seen it happen time after time on tests and have it happen twice myself. Once on a
demo.

If you dive out of the plane, head down, back to the tail and pull immediately, you canopy will open, you will swing under it. The will still be horizontal relative wind and it can blow you PC over the nose of the canopy.

Sparky

My idea of a fair fight is clubbing baby seals

[billvon 2,991]

>I have seen it happen time after time on tests and have it happen
> twice myself.

I've seen it happen perhaps 20 times. Some of those times were during SL with a springloaded PC, before we went to direct bag. The jumpers who faced forward had it happen at about the same rate as those that screwed up and turned as they left the aircraft. I actually saw it more often during AFF - which is one reason we switched to throwouts.

>If you dive out of the plane, head down, back to the tail and pull
>immediately, you canopy will open, you will swing under it.

Agreed.

>The will still be horizontal relative wind . . .

Not once you have swung under your canopy; at that point you will just see the normal relative wind. Your canopy cares only about relative wind, not about where down is. That's why downplanes and dragplanes work.

[mjosparky 4]

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>I have seen it happen time after time on tests and have it happen
> twice myself.

I've seen it happen perhaps 20 times. Some of those times were during SL with a springloaded PC, before we went to direct bag. The jumpers who faced forward had it happen at about the same rate as those that screwed up and turned as they left the aircraft. I actually saw it more often during AFF - which is one reason we switched to throwouts.

>If you dive out of the plane, head down, back to the tail and pull
>immediately, you canopy will open, you will swing under it.

Agreed.

>The will still be horizontal relative wind . . .

Not once you have swung under your canopy; at that point you will just see the normal relative wind. Your canopy cares only about relative wind, not about where down is. That's why downplanes and dragplanes work.

I'll note your views on the test flash report next time it happens.

Sparky

My idea of a fair fight is clubbing baby seals

[azureriders 0]

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during deployment the relative wind can take your P/C and blow it over the nose of your canopy

Is this realy that big of a problem. In my FJC I was taught that a PC over the front is NOT a malfunction and NOTHING to worry about. "has happened to me several times" was what my coach said.

I think if I had this happen that I would keep a very close eye on it until my hard deck (and even after for what good it would do) but my question, without intent to further highjack this thread, is how big a deal is a PC over the front?

[NWFlyer 2]

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is how big a deal is a PC over the front?

Like any malfunction or potential malfunction you should look at it and evaluate it carefully above your hard deck. I had this malfunction as a student, jumping ripcord gear with a spring-loaded pilot chute. When I first looked at the canopy it looked like a line-over, and another jumper observing me said it looked like one from his vantage point as well. It wasn't a line-over, but the PC was heavy enough and had gotten wrapped around the lines a bit and was dragging the corner of the canopy down and had the canopy in a slow turn.

I considered it a "big deal" and I chose to chop it given the gear I was using and the configuration that it ended up in. Your situation/gear may be different.

"There is only one basic human right, the right to do as you damn well please. And with it comes the only basic human duty, the duty to take the consequences." -P.J. O'Rourke

[AggieDave 6]

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I considered it a "big deal" and I chose to chop it given the gear I was using and the configuration that it ended up in. Your situation/gear may be different.

I've had PCs and tandem drogues over the nose, in the lines, in the control lines, wraped with my C-lines (still haven't figured out how that one happened), but I've yet to have to chop any of them. I'm not saying that it couldn't be a chop-able offense, just that there's not a hardfast rule. If the canopy flies and flies correctly, then meh, if its not flying correctly, then you've got a decision to make.

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

[NWFlyer 2]

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if its not flying correctly, then you've got a decision to make.

Precisely my point. I hope that's the kind of decision-making ability his instructors are helping him to develop.

"There is only one basic human right, the right to do as you damn well please. And with it comes the only basic human duty, the duty to take the consequences." -P.J. O'Rourke

[udder 0]

why such a short delay?

"In one way or the other, I'm a bad brother. Word to the motherf**ker." Eazy-E