Feb 16, 2006, 12:07 AM
Post #1 of 65
Stalling my canopy
OK, so I search through the forums and found a little info but not the answers I want. so I thought that I would just ask you all. first things first, I intend to talk to my instructors about this but I would still like to get your answers.
1. is it safe to stall the chute? when I learned to fly airplanes we stalled the plane alot to learn what an approaching stall felt like. is it ok to stall the chute up high to learn?
2. I'm currently flying a saber 2 210 and I'm 175lbs + gear. How will this canopy stall? I've read that some bow in the middle others end cells colaspe.
3. how high would you recommend that I be to try stalling? I normally pull at around 5000. mostly because I like to play under canopy. should I plan to pull even higher?
Stall practice is part of most canopy control classes. It certainly was in Scott Miller's class. Some high performance canopies he would recommend you not do stalls, but a sabre2 is fine for stalls. I recommend you do it, but I'm a nobody. Get some coaching on the details.
When it stalls, don't let your arms fly high immediatly. That will cause the canopy to surge forward and dive, and you'll eat up a lot of altitude to recover control and the canopy may do funky things(During a demo on a S2 190, to center cells collapsed due to this for 5-7 seconds and started a medium turn). Raise your toggles up a few inches to when you feel you get the same control as on deep brakes. Your instructors can fill you in on the details, since I'm not an instructor and my english is crappy.
As an instructor if I had a student with 15 jumps come up to me and say he got advice on how to stall a canopy on the internet I’d be mortified.
Scott Miller (who’s class I suggest to everyone) has a 5 step progression in learning about a canopy. Toggle and rear riser stalls are part of that progression.
Do you know the effect on flight of front and rear risers, do you know what surging the canopy does? Have you finished all the canopy control items on you “A” license card? If not than your ahead of yourself with wanting to stall a canopy.
You should be getting canopy coaching as part of your “A” license. Tell your instructors your desire to stall your canopy and let them build a progression path for you.
My first jump on my pilot 150, I pulled really high to put it through the ringer. I gave it a deep stall and coming out of it, it spun up on me about 6 or 8 times. I had major line twist to kick out of.
Thanks guys, I know that I am most likely getting ahead of myself. I guess I want to find out more about stalling because I don't know how the chute will react to a stall, so in turn it scares me a little. (insert tuff guy cover up here) it was the same way when I was learning to fly airplanes. stalls were very unnerving, till I did one and realized that when the wing stops flying it is manageable. I'm getting the Idea that it is simaler in parachuting. I am planing to take more advanced canopy control classes. so not to fret I am taking this advice as nothing more then advice I will talk to my instructors (today hopefully) and build a plan. I just want to learn this not to just play with it but so I feel safer under the canopy. and your experience is a great learning tool.
If you can pull your toggles down as far as you can reach, and the canopy does not stall, you're pretty safe from an unintentional stall, and may not be getting 100% of the flare performance. So it's good and maybe a little bad (just maybe, and only a little).
That, said, you jump at one of the top DZ on earth. Ask for some help there. Maybe book a canopy coach for an hour, and get some ground training. Do a hop n pop, try some stalls, and have the coach critic your landing. It should be cheap and well worth the price.
Thanks guys, I know that I am most likely getting ahead of myself. I guess I want to find out more about stalling because I don't know how the chute will react to a stall....I am planing to take more advanced canopy control classes. so not to fret I am taking this advice as nothing more then advice I will talk to my instructors (today hopefully) and build a plan.
This is very good to hear.
As for the stall, what you will feel is that you will stop moving forwards. You'll feel a loss of weight on your leg straps and begin to fall backwards...and it will probably scare the shit out of you.
Your canopy will do one of several different things depending on chute type and size, air currents, how quickly you stall it, and just plain chance. Some of those things are bad - your instructor will explain.
The first time I did a stall, I released slam-bang quick because it scared the shit out of me and the canopy surged and I saw the horizon WAY above the tail of the chute - and this was on a 190 Triathlon.
After you get the hang of it, it becomes fun but really not something you want to do an a daily basis tempting fate.
You may need to wrap the steering lines several times around your hands to get that canopy to stall. Be sure to talk to your instructors about how to do this (or not do it) safely.
Wrapping the steering lines around your hands several times may make it very hard to release them if you need to cutaway. You might need to cutaway if you let the toggles up too fast after stalling, this can cause such a quick turn that you can get severe line twists.
...I did my first intentional canopy stall at about 15 jumps. To get an A licence in Australia, you need to complete a canopy handling table, which includes static & dynamic stall recovery.
Congrats, Dave. I'm sure there's someone out there who has done it in less jumps - not good IMHO. I would not recommend everybody doing so at 15 jumps. I am part of the "slower progression" school of thought.
In reply to:
.If properly briefed...
I think that has already been addressed with several comments about "talk to your instructor." 15 jumps is not a magical number for anyone to start anything. It is an indicator of inexperience, though.
You will get a more definitive answer from Brian Germain, if that's what you are looking for.
(This post was edited by popsjumper on Feb 16, 2006, 4:01 PM)
Could be...so what do you want to hear? Something like, "I will lower my standards on safety?"
is it really a lowering?
BTW, Brian has people try to do that on their first jump in his weekend course, if only to see if it would stall or not. As might be expected, my rental was happy to fly slowly at full toggle (w/o wraps).
Before we discuss how to find the stall point of a parachute let's define Stall Point and what happens to a parachute when it stalls.
The Stall Point of a parachute can be described as the point when the parachute is no longer producing Lift. This is caused by an excessive Angle of Attack. Angle of Attack is often defined as the angle between the cord line (a straight line between the leading edge and the trailing edge of a parachute)and the Relative Wind.
When a Standard Ram Air Sport Type Parachute opens properly its shape is typically rectangular or elliptical. The cells of the parachute are inflated with air. These cells will normally remain inflated as long as the Angle of Attack has not been exceeded.
A simple way to Stall or exceed the Angle of Attack of a parachute while airborne is to Pull Down on Both Steering Toggles at the same time till the Parachute Deflates or Collapses.
It is important that Skydivers be able to recognize when a parachute is approaching its Stall Point, How to Stall, and How to Recover from a Stall.
To find the point where a parachute is approaching its Stall Point:
1. Check to see that the parachute is working properly
2. Check that you are clear of other traffic
3. Check that your location and heading will allow you to land safely
4. Check that your altitude (2500 feet the first time) is sufficient to recover
5. With steering toggles in each hand, pull them smoothly down together while looking up at the bottom skin of the parachute. As you approach the Stall Point, the bottom skin of the parachute will start to wrinkle.
6. Look to see where your hands are, this position should not be exceeded for the Landing Flare, to do so may cause the parachute to Deflate or Collapse
To Stall the parachute ( refer to above 1 thru 5 on approaching the Stall Point), then continue to pull down both steering toggles till Collapse or Deflation occurs. Standard 9 Cell parachutes when Stalled will normally turn initially, then with further deflation the corners of the tail will touch each other and the parachute will descend at a higher than normal rate. It is Important to note that Skydive The Ranch sets the Steering Toggles on the Main Parachutes so they are difficult to Stall, while the Reserve Parachutes are set to manufactures limits and will normally Stall if the Steering Toggles are pull down too far.
To Recover a Stalled Parachute, smoothly return both steering toggles to the half brake position (Some high performance parachutes may have difficulty reinflating properly once stalled due to severe self induced line twist. Always check the manufactures operating instructions before attempting to stall a parachute.) If Stall recovery techniques are done too quickly, it increases the parachutes tendency to surge forward ahead of the skydiver. If this happens close to the ground, the parachute and the skydivers body can hit the ground at approximately the same time. This type of landing is normally refereed to as a Face Plant or Full Body Slam.