pulling out of a track

[guest]

Referring to: Knowledge BASE/technique/subterminal tracking

Hi Lukas,

I just read your article about subterminal tracking. You point out not to "flare", i.e. not to stop forward motion before the pull to obtain better openings.
Obviously you have good results with it, but still I have to disagree with you on that technique.
- If you pull in a really strong track, the canopy doesn't leave the pack-tray in the direction it is supposed to and might be misdirected by the lower corners.
- I imagine that because your body is swung around a lot more when you pull with lots of forward motion, it is likely that the effects of the smallest asymmetry in body-position are intensified.
To minimize the swing of the body and to slow down forward motion I actually transition from a hard track into a 45° uphead position during the slow-down / pull sequence.
In this context don't forget the forces working on your body:
A couple of years ago I were almost knocked unconscious by an opening while standing on a 4 ft-board (pretty fast) with probably lots of forward motion.
It is a known fact that you get slamming openings when pulling out of a track when using canopies like the Sabre (like I did on the above mentioned opening) - just ask any experienced skydiver. Because newer designs like the Stiletto, Velocity etc. open so softly anyhow, you can actually do it with them, but it still speeds up the opening considerably. But here we are talking about Base-canopies which are already packed for fast openings (I usually use a mesh-slider also on terminal jumps).

Why do you think it is a good idea to pull out of a track?
Any comments from other readers?

Obi

[guest]

I would have thought that the low track speed at sub terminal would be of no significant effect to the deployment...at say 8-10 seconds it may make a difference...it should however make cell 3 sit up into the airflow and inflate nose first...in PRO style...bearing in mind that the pull on the canopy will be running chordwise through cell 3...depending on what style of slider up pack job you have it will make for a harder opening then for sure...just a thought or three

[guest]

I pull pretty much in full flight with my wingsuit (classic, Gti and Skyflyer) and the openings are fine. I tend to tuck my legs a little when I go to pull, so that's a bit of a "flare," but I pull without waiting for that flare to have any signigicant effect.

The main thing is to make sure your shoulders are even because, as one poster said, the higher speed magnifies the effects of slight differences in shoulder position.

As for off-heading and line-twisted openings, I found it much better to just keep on tracking after the pull because then everything stays in alignment and I have very consistent clean compeltely straight openings now on the wingsuit, and they aren't especially hard, even though the combined horizontal/vertical speed is probably in the 150mph range.

As for the different deployment angle, it would be pretty hard for that to affect anything, especially with BASE rigs that have essentially no corners anyway.

[guest]

:o maybe I meant cell 4.Doh!

[guest]

Something else I noticed in there was the recommendation to wear a tight, slick suit for max track.

> It might be possible to get there with a low pull from Kjerag #5 if one wore a very slick speed skydiving style suit.

Is this the received wisdom? Will a tight, slick suit give a better glide ratio than a loose (i.e. freefly) suit? Or will it just give a faster forward track (with corresponding faster fall rate)?

Does anyone have any info on the best clothing to wear for tracking (to achieve best glide ratio, as opposed to max speed)?

Obviously, the best answer is a wingsuit, but what's the second best?

Clearly, my lack of airplane jumping is showing...

--Tom Aiello
tbaiello@ucdavis.edu

[guest]

The best trackers at Kjerag usually use suits with booties.

/Micke

[guest]

Hi Obi,

On skydives I have a very real dislike of getting smacked from my Velocity so I always flare before pull to reduce my airspeed. Besides the Velocity opens really very quirly and requires a completely different mindset than a Mojo. You can't really compare the scenarios. From Kjerag I jump a sail slider (it now has a mesh zone in the middle of it) and I have yet to get a painful opening, so airspeed isn't the problem.

My mantra definitely contains alot about body position, and anybody who knows me (Swedish BASE scene), knows that I preach it. So the other poster who mentioned body position is definitely correct. More airspeed, more critical. But it is very easy to solve,
1.) Think symmetry.
2.) Don't look at your deployment over your shoulder, pitch it hard 'n' good and look straight ahead again.

Besides the airstream is a lot smoother behind a max track than behind a head high position and a small horizontal distance advantage is gained as well. Could be the make or break between reaching the water from number 6 at Kjerag. Smooth air makes smooth openings.

I know that many experienced wing suiters (I am NOT one yet) are pulling in full glide and returning to full glide during canopy extraction rather than collapsing wings, although some are also concentrating on cutting away the wings as well.

As for the corners of my Perigee Pro obstructing deployment, I really doubt it. I would welcome info that points out the contrary. PLaying with the rig on the ground and watching it (wrist slap!) almost incline me to say that the corner pockets are benificial, they stage deployment a little. The corner pockets on my skydiving Micron Vector really hold the bag in, something which I think is detrimental to wing suit skydiving, but as for the perigee Pro I think they work good.

The slick suit enables higher airspeed, ask any skydiving speed diver. The slick suit in question is something that long distance skiers wear, its really tight. Higher airspeed means more lift, flatter glide. Wing suiters have more wing, ie more lift, ie more glide. Freefly suits are just drag, they are meant for sit & upside down flying. They are detrimental to gaining forward speed in tracks, although they do feel easier to control.

My thoughts sisters & brothers. Please be careful out there.

Lukas Knutsson.

PS What is the total fall height of Half Dome, ie to the valley floor.

[guest]

The Dome is 2000' to the top of the talus, 5500' to the valley floor. Norway doesn't have a monopoly on all the big stones...

Care to come and play?

--Tom Aiello
tbaiello@ucdavis.edu

[guest]

Sounds fun, but I got busted there in 1990. I paid my fine and all, but still it feels weird to entertain the idea of going there after that grief at the Rostrum.

As for 5500' thats good, real good, but there are plenty of bigger walls being opened in Norway. One minute wing suit glides will soon be commonplace.

<lukas/>

[guest]

Sounds like a case of "Mine is bigger than yours, na na na na na" or "Aything you can do I can do better".

Well at least it's more fun than reading cat fights between squabbling bitches

[Yuri]

Robin,

I absolutely agree that pulling in a full track/flight is the best option on any BASE jump, with or without a wingsuit. According to my personal statistics, max horizontal speed IMPROVES openings considerably.

More importantly, "flaring" out of a track is a mortal sin of WASTING ALTITUDE! Usually it is embarassing, sometimes it's lethal.

Regarding hard openings: if you track well, your total airspeed is still around terminal or even slower.

Sleek suits will definitely give you the best glide ratio: faster horizontal and slower vertical speed. Freefly suits are specifically designed to create drag and succeed at that.

Finally, on a wingsuit deployment: even in a full flight on Skyflyer, your true airspeed is probably BELOW terminal. According to GPS my combined horizontal/vertical speed is around 90mph. Classic is even slower.

bsbd!

Yuri.

[guest]

Don't it just ! I think as the size of a community grows it can contain more and more fringe members who make a disproportionate amount of noise. Here is Sweden we have a big party every year for just BASE jumpers (non jumping friends are not allowed) and everybody knows and jumps with each other and the mailing list serves as a good information dispensing forum. Since we have so few relatively good objects we have to take care of them co-operatively. We noticed when we were 9 standing at the exit of 400' bridge one night.
<lukas/>

[obi]

Hmm,

I'm surprised to read that so many experienced people like to pull out of a track and therefore glad to have brought up the discussion. Another very experienced friend of mine told me not to do it, but I allways like to hear different oppinions and then make up my own.
So how do you guys do it exactly (I'm not talking about wingsuits)? Do you grab the PC in full track, throw and prepare for grabbing the risers? Or do you return into track after the throw?
Don't worry, I'm not into getting a theoretical instruction here... I'm just interested since I think one should never stop learning.
Obi

P.S. Yuri, you're right, me too I find it embarrassing to "waste" "trackable" altitude during the flare. I just thought it is good for the opening and therefore not wasted.You just have to start early enough :-)
P.P.S. Lukas, I totally agree with you that the design of the Perigee Pro makes it easier for the canopy to leave the pack-tray, especially when it is pulled backwards. I just thought about optimising everything.

[space]

Somethings to think about. A good hi-lift track is some what unstable due to the fact there is no positive arch that increases stability. The better your track, the more unstable you are due to the fact the aerodynamic control envelope is very narrow at this manuver. Just as you have to fly the track, you have to fly the in-track deployment sequence. Going unstable at deployment time is nasty and has resulted in one known fatality recently from the inability to get out of linetwists before striking the object. I know of around a half dozen incidents of jumpers going unstable while pulling in a track. All were new or beginners to the sport of Tracking BASE jumps. I think all of them had line twist, and some had injuries mostly from their head interacting with the risers and some lost one shoe or both.
So I guess the Moral to the story is to practice pulling in a track with simulated pulls from an aircraft before pulltime.
I always pull in a hi-lift track on trackable jumps, and never gave it much thought, until watching and hearing about these incidences.
It all goes back to plan the dive, dive the plan, but make certain you have the skills for the dive first.
Take care,
space