0
northcave

Jump the Jet - opening heights

Recommended Posts

I was watching the video of everyone piling out of the back of the DC one after another with about half a second gap inbetween each one.

It made me wonder wouldn;t they have problems over opening times and people flying into others canopies or opening and then having collisions.

Its easy when u have a 4 way for example and can track in opposite directions but when you havw so many at different levels.

Whats everyones else thoughts and has anyone done it that can talk from experience?

:P

Share this post


Link to post
Share on other sites
The jet flies much faster than your standard jump planes. There is a lot more horizontal separation than you might think.

When I jumped it at the WFFC last year there was plenty of separation and we exited one right after another as you described.
__

My mighty steed

Share this post


Link to post
Share on other sites
Quote

The jet flies much faster than your standard jump planes. There is a lot more horizontal separation than you might think.

When I jumped it at the WFFC last year there was plenty of separation and we exited one right after another as you described.



For the half second northcave mentioned to be enough separation, the jet would have to flying really fast. Not sure I would want to exit at those speeds. B|
Dave

Fallschirmsport Marl

Share this post


Link to post
Share on other sites
Quote

Quote

The jet flies much faster than your standard jump planes. There is a lot more horizontal separation than you might think.

When I jumped it at the WFFC last year there was plenty of separation and we exited one right after another as you described.



For the half second northcave mentioned to be enough separation, the jet would have to flying really fast. Not sure I would want to exit at those speeds. B|


I'm thinkin that it was more like 1 or 2 seconds, and jump run was somewhere around 150 mph
__

My mighty steed

Share this post


Link to post
Share on other sites

Haven't jumped the DC9 yet but when we did the 727 it was the first time I exited an airplane and immediately started to slow down. Pretty cool sensation. Also, if you exit facing the relative wind and hit a hard track you can almost hold altitude with the airplane for a few seconds. Very cool. B| A good wingsuit flyer could certainly gain altitude on it.



Skydive Radio

Share this post


Link to post
Share on other sites
when i had jumped the jet, i was uncomfortable, they said that there was plenty of seperation, but from what i saw, people were close. groups trying to get together had people popping into the wrong group. It did not help that it was my 2nd time jumping at perris, first one was off of chopper so had sky to self.
CLICK HERE! new blog posted 9/21/08
CSA #720

Share this post


Link to post
Share on other sites
Quote

Can you feel the 150mph wind hit you? Does it just send you all over the place?



Super Connie did at 155 mph, when I exited through the smaller door.

However, the Casa offers 200 mph exits when there is enough interest, with one caveat, NO GRIPS on launching groups! B|
"Mediocre people don't like high achievers, and high achievers don't like mediocre people." - SIX TIME National Champion coach Nick Saban

Share this post


Link to post
Share on other sites
When you mention opening height, are you talking about using pull altitudes as a measure of separation?

In most instances relying on vertical separation is shady at best!!
"The restraining order says you're only allowed to touch me in freefall"
=P

Share this post


Link to post
Share on other sites
>For the half second northcave mentioned to be enough separation, the jet
>would have to flying really fast.

Well, it runs it at 140kts, which is about 185mph groundspeed on a no-wind day, or 271fps. If you have all four-ways, and everyone exits .5 seconds apart (which is hard to do; that's fast) then you have 2 seconds between groups, or 1085 feet between groups, which should be OK. If people screw up and end up all going after the first/last person you could see trouble; an extra second between groups could help alleviate that.

Share this post


Link to post
Share on other sites

It made me wonder wouldn;t they have problems over opening times and people flying into others canopies or opening and then having collisions.

Its easy when u have a 4 way for example and can track in opposite directions but when you havw so many at different levels.

Whats everyones else thoughts and has anyone done it that can talk from experience?:P



Actually, for starters the jet flies a jump run that's perpendicular to the normal line of flight, so everyone's making a crosswind approach to the center of the dropzone. That helps.

The other thing is that they explain at the briefing, about half an hour before flight time, that since the jumprun (at Perris anyway) will be east to west, you're expected to track either to the north or south. It's up to you which way you want to go, but it needs to be north or south (both are parallel to the Perris runway).

So in the end you have around 40 people exiting on each pass, plenty of horizontal seperation due to the high speed of the plane and half the people tracking one way, half going the other. I found it wasn't much worse than the average midsize RW load, though I also found there was a lot more vertical seperation, perhaps because some people were freeflying and falling faster (I'm a belly flier).

A friend of mine with barely fifty jumps at the time made a jet jump and felt completely comfortable with the traffic issues.

Your humble servant.....Professor Gravity !

Share this post


Link to post
Share on other sites
Quote

how long is the ride to alltitude, is their a/c

The ride to altitude was about 4 or 5 minutes when I jumped. I remember it being quite pleasant on a hot day, so I assume there was some sort of adequate ventilation.
I really don't know what I'm talking about.

Share this post


Link to post
Share on other sites
Quote

Can you feel the 150mph wind hit you? Does it just send you all over the place?



If it's anything like a C-130 at 130kts, then I say yes...:)

It's not impossible to fly through it, but yeah, it can toss you if you're not prepared. ;)
So I try and I scream and I beg and I sigh
Just to prove I'm alive, and it's alright
'Cause tonight there's a way I'll make light of my treacherous life
Make light!

Share this post


Link to post
Share on other sites
Quote

The jet flies much faster than your standard jump planes. There is a lot more horizontal separation than you might think.

When I jumped it at the WFFC last year there was plenty of separation and we exited one right after another as you described.



That was definitely NOT my experience on the first WFFC jet load. Way too close for comfort. The plane goes 50% faster on jump run than normal, but if people follow each other as quickly as possible (as instructed by the jet's staff), it more than cancels out the extra separation provided by the additional air speed.
People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

Share this post


Link to post
Share on other sites

Hi Cliff

Quote

That was definitely NOT my experience on the first WFFC jet load. Way too close for comfort. The plane goes 50% faster on jump run than normal, but if people follow each other as quickly as possible (as instructed by the jet's staff), it more than cancels out the extra separation provided by the additional air speed.



Quote

Your experience Might be due to the difference in your position in the stick, We were at the ass end of the next to the last stick and by the time we got to exit there was plenty of seperation.

Did you land on the airport? We landed WTF off, next to the road. Quincy folks were real nice:) No walkingB|

Me bad:S difference in seperation could be due to 727 vs DC-9[:/]

Share this post


Link to post
Share on other sites

I should have made it clear that my jet jump wasn't really the first WFFC jet load, it was the first jet load of the '06 WFFC :D.

I was about the 10th person out, so it was still easy for people to exit very quickly after each other. The spot was good.

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

Share this post


Link to post
Share on other sites
Quote

I should have made it clear that my jet jump wasn't really the first WFFC jet load, it was the first jet load of the '07 WFFC :D.

I was about the 10th person out, so it was still easy for people to exit very quickly after each other. The spot was good.



Hi Cliff

The sport is growing:)
The "jet" with or without windows ? :)
No complaining about our spot:)

Share this post


Link to post
Share on other sites
I remember jumping the jet at the wffc, My group were sitflying right past a group on their bellys and then we saw people passing us head down.

We never really gave it a second thought with exit spots as i guess everyone one on the jet was too excited that it must have just passed all our minds.


.Karnage Krew Gear Store
.

Share this post


Link to post
Share on other sites
Does anyone besides me remember doing 727 jumps at Quincy in 99? I recall that the exit speed on the last pass for the jet was approaching 240, and they were doing 10-way speed-star competitions out of it...It was a kick-ass ride!!!



If you are not living on the edge, you are taking up too much space.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

0