Dealing with 2 Squares Out and Double Sided RSL
All users of any RSL should be taught and should practice the following: After confirmation of a good canopy over your head Disconnect the RSL! This prepares the jumper for high ground winds and a cutaway after landing without activating the reserve. Additionally, this procedure prepares the jumper for in flight canopy involvement with other canopies, as well as for dealing with the two canopy out scenario. If, in the event both canopies deploy, the following is a guideline for dealing with them.
The need for a clean deployment of the second canopy is becoming more and more apparent. Do not try to stop it. This is a good time to undo your RSL. If anything, try to assist it through a clean, no line twist inflation. You might release the brakes of the first canopy to give more speed for the second canopy’s deployment.
During this time you should, as always, keep “one eye on the ground” but recognize that your rate of descent has been abated and that you have time for analysis and action. Cutting away, in this situation, is considered an advanced procedure, and should only be executed by experienced jumpers. It should not be taught to students. There are too many variables. Analyze your situation. Try to keep the two canopies in a bi-plane. They may go to a side-by-side, but you can steer them. Just do it gently. Manipulate the outside toggles of a side by side. Steer with both sets of toggles in a bi-plane, do not allow the canopies to separate, keep them together. Make all turns slow and flat and with plenty of altitude. A student can be talked through this situation.
Now to the advanced procedure of cutting away the main. The best configuration for cutting away, is from the down plane. Keep the toggles and risers and bridles and pilot chutes of the two canopies as far away from each other as possible. Some folks have found that it is OK to cutaway from a side-by-side, but more caution is advised from this mode.
If you experienced line twists of the second canopy during deployment, it might dip and dive, momentarily enter a down plane, and pass right on through it as it tries to untwist and equalize suspension tension. It might twist up into an unsteerable, uncontrollable mess which goes into a downplane. This is the most dangerous time and the most difficult situation to deal with. Timing is the secret. This process of unwrapping, if it occurs, is redundant for each wrap or twist of lines. Observe your altitude and by pulling gently on a toggle of the line twisted canopy, you may effect the cyclic speed of the untwisting. Be careful to pull the toggle that will untwist, to accelerate the cycle, and the toggle that will twist and tighten to slow the cycle. Hopefully, we will be untwisted before landing. If not, we will hopefully be in either the side-by-side or bi-plane phase upon landing. If you are having a real bad day and you find yourself approaching a landing with a personal down plane, FLAIR the steerable canopy. This is, as of yet, an unproven procedure, but at this point you are better off doing something than nothing. Again, an experienced jumper might elect to cutaway during the down plane phase of the cycle. Check your altitude first, experience has taught you what the altitude requirement will be to oscillate down to a vertical orientation.
Selection of canopies seems to play a part in the low propensity to down plane. Major departures in the size differential of the main and reserve seem to be more unstable. Mains and reserves should be matched as closely as possible. This is difficult for the accuracy rig jumper as there are not many reserves that big and using a similar sized reserve makes for a prohibitively large rig. Student rigs should also be fitted with similar size canopies.
Please note that I have used the identifiers of “first” and “second” canopies instead of main and reserve. This is because either one could be first. Also note that the larger canopy will usually dominate. It is a good idea to determine what each canopy’s tendencies are before touching them, i.e., which canopy is bigger, which canopy is in front at the harness attachment point and which canopy is in front at the canopy level. These two configurations are generated each in turn by which canopy comes out first. For example, if you pull your main at 1500 feet, you sit in at 1200 feet and your Cypres fires (Which seems to be the most common occurrence). You now have proper orientation of your main reserve risers as well as the respective canopies.
If the reserve fell down in back of and below you and the lines twisted up during inflation, say three turns, the reserve canopy would probably initially orient to a bi-plane or side-by-side. If it should open with the nose facing the earth, it will initially fly in that direction. However, the tension of the line twists, if they are asymmetrical, will force the untwisting. The canopy will always fly in the direction it is pointing. As it untwists, the direction the nose is pointing changes. Therefore, it will change locations as it cycles about the axis of the other canopy.
In the above scenario the main canopy could be cut away during the cycled down plane orientation of the reserve canopy. This could be done without disconnecting your double-sided RSL. However as we stated above, and for the sake of consistency on all rigs with RSL’s the RSL should have already been disconnected before we released our brakes. Incidentally, if you did cutaway your main in this situation it would leave you under a reserve with line twists, which might not untwist before you land.
The potential for a Double-Sided RSL to lanyard choke the reserve risers (THIS IS THE ONE EVERYONE LIKES TO TALK ABOUT) can only occur when the main is in back of the reserve canopy and in front at the riser attachment. That would mean a deployment of the reserve occurred before the deployment of the main. You might not want to cutaway the main canopy even without an RSL in this situation because of the twisting of the main lift web and the involvement of the main and reserve risers and toggles with each other. Much of the variance in this scenario has to do with the amount and location of the twists of the lines, if any, on the main.
All in all the choices are too complex for students and must be resolved upon a case by case basis. Therefore, students should be taught like every one else but without the option of cutting away. Many DZ’s don’t want to teach releasing the RSL as they don’t teach cutaway for relief of ground drag. They teach pulling a toggle and keep pulling. Having to remember to release the RSL is more than they wish to burden the student with. If that is the case they certainly can’t expect them to make an evaluation of the above described conditions and then decide whether to cut away or not.
We must therefore keep all students from being exposed to these dangers. After the jumper has progressed to a level where they can understand this complexity then we can add the option of cutting away with or without an RSL.
This document is but one of three documents which must be read and understood. In that some of the data is commercial I feel that posting it on a newsgroup forum would not be proper. I am therefore posting them to the Jump Shack Web page. Please read:
What you should know about RSL’s
Your response is solicited. Before you respond I ask that you read all three of the documents and think about all of the possible scenarios. Remember, not all failure modes are possible to solve in this sport. We must select our emergency procedures and configure our gear to accommodate those situations which occur most frequently.
I will gladly respond to any and all intelligent questions. I encourage open discussion, it is how I learned…