What’s Your Wind Limit?

Gusty winds are common at Spaceland and many other dropzones. As an experienced jumper, I have thought a lot about what my personal wind limit is–in other words, when I will sit down even though the dropzone is not on a wind hold. Recently, I made the decision not to jump after watching other fun jumpers and tandems land. Later in the day, the tandems went on a wind hold. I was surprised to see that many newer jumpers flying larger canopies with lighter wing loadings than I have continued to jump that morning and afternoon, even after the drop zone put the tandems on a hold.

Once you graduate from the Skydiver Training Program, you are responsible for determining your own wind limit. What is safe for someone with 100-200 jumps flying a canopy loaded around 1.0 is very different from what is safe for someone with thousands of jumps on a crossbraced canopy. To quote Brian Germain,” …until your skills and knowledge are ready to fly smaller, faster parachutes, you should stay out of the sky until the winds come down. I still haven’t been hurt by a jump I didn’t do.”

There are many questions you can ask yourself and ways to observe the conditions at the DZ that will help you make a safe, informed choice. I often ask myself the following:

  • Are people with more experience than me sitting it out? 
Particularly, are people with thousands of skydives standing down?
  • How are the landings of other people jumping canopies loaded similarly to yours?
  • Are they coming straight down or landing backwards?
  • Are their canopies “breathing” a lot or do you see their end cells folding under?
  • What is the spread between the peak gust and lowest reading on the wind-meter at manifest?
  • Is the wind sock standing straight up and then going limp, or whipping up and down?
  • What is the wind direction, and is it consistent or changing?
  • Are there obstacles near my target landing area that are likely to cause turbulence?

Just because you can jump, doesn’t mean you should. What is your personal wind limit? What do you consider when you decide whether or not it is safe for you to jump?

Factors You Should Consider

How your canopy’s groundspeed will affect your accuracy and landing

Consider the speed of the uppers and the speed of the winds on the ground. If you are on a lightly loaded canopy, you may not “penetrate” into the wind—this means that it may be harder for you to make it back to the drop zone. You will want to pay close attention to your heading on opening so you do not unintentionally fly your canopy downwind of your targeted landing area.

Strong winds also mean that you may have to “crab” the crosswind leg of your pattern, because you will experience a push away from your target while flying this leg of your pattern. You will also need to be ready to see some different sight pictures under canopy: your canopy may be pointing one direction and moving another. Then, on your final approach you may come straight down or go backwards. You will want to be able to plan your pattern in light of these conditions. You will want to avoid flying over any obstacles. If you are getting very little penetration into the wind, you will also want to make sure that you are flying your canopy in full flight—without any pressure on your toggles—until you begin your flare. Preserving as much forward speed as you can will improve your flare, and flying in full flight will reduce your vulnerability to turbulence.

Strong winds will also affect how you land your canopy. When you start your flare, you may start to go backwards. You will need to be prepared to deal with how this may change the speed and depth of your flare—you still need to flare after all—and be confident in your PLF.

As you land and begin to unload your canopy, you will need to be prepared to collapse your canopy quickly using your risers or a steering toggle. Otherwise, your canopy could continue to fly and drag you (and your beautiful rig) across the landing area. Many experienced jumpers have different tricks that help avoid them from getting dragged. Some examples are stepping on your d-bag or canopy and “running around your canopy”. Your mileage may vary, so be sure to develop a method that works well for you. If you make a mistake and your canopy drags you quickly and violently, you may need to disconnect your RSL and cut away your main.

Finally, in the event that you have a bad spot or experience a malfunction, how comfortable are you dealing with all of the above while landing off? You should always be sure to know the outs at the dropzone where you are jumping and consider your ability to land your canopy accurately and safely in an unfamiliar area.

The above are only some of the considerations and skills that go in to deciding if you can fly and land your canopy accurately and safely. Even if the winds are not gusty—just strong—you should be sure to consider whether or not you have the skills and confidence you need to land your canopy in those conditions.

To summarize, here are some questions you should ask yourself before jumping any day where the winds are strong.

  • Will I make it back if the spot is less than perfect?
  • Am I comfortable landing off the drop zone in less-than-ideal landing conditions where I may not be able to see a windsock?
  • How strong is my ability to fly a proper, accurate landing pattern? Am I likely to misjudge the conditions and land on an obstacle if I come straight down? Do I have the skills and awareness necessary to avoid obstacles?
  • Will I be able to pay attention to and account for canopy traffic while landing in strong winds?
  • Are the winds strong enough relative to my wing loading that I could land backwards and if so, do I really want to land backwards?
  • Can I collapse my canopy quickly and effectively or am I likely to get dragged by my canopy?

How turbulence will affect your ability to fly your canopy safely

Many of the factors discussed above are things you can learn to control with canopy coaching and the appropriate level of experience. You may feel that once you have 200 jumps and fly a canopy at a non-student wing loading, you can jump in any conditions you want. If you feel this way, you may either be overconfident or have forgotten the effect that turbulence has on your ability to fly and land safely.

Turbulence created in gusty conditions may cause your canopy to collapse or your end cells to fold under. Obviously, this will impact your ability to fly and flare your canopy. If the “spread” between the peak gust and lowest lull in the wind speed is high, many canopy pilots experience a bumpy ride. Typically, jumpers consider anything over about a 10 mile an hour difference between the average wind speed and the peak gust to be high enough to cause trouble. So, if the winds are 10 gusting to 21, many jumpers will choose to sit down because the air feels “dirty” or “bumpy”. If you watch the windsock and it whips up and down, it is a good indication that the conditions are gusty and bumpy. Often, the best way to determine if the conditions are bumpy on a particular day is to watch other jumpers land. If you are concerned, ask the jumpers who just landed what the conditions were like.

You may also have a bumpy ride if there is mechanical turbulence caused by obstacles near the landing area. As a student, you learned that mechanical turbulence exists directly above, upwind, and downwind of large obstacles. On the downwind side, turbulence may be encountered at a distance equal to at least ten times the height of the obstacle. If you catch mechanical turbulence that causes a rotor, your canopy may speed up and increase its angle of attack. You could experience a sudden drop or surge that makes it feel like your canopy has lost lift. If you experience turbulence close to the ground, you may “drop” out of the sky and you need to be ready to take whatever countermeasures are necessary (if you are at flare altitude, typically stabbing out a flare) to stay under your canopy and also be prepared to PLF.

At Spaceland for example, the hangar is a source of turbulence in the D license landing area when the winds are out of the north and the landing direction is toward the hangar. It’s really easy to catch turbulence off the building if the winds are strong and there is even a slight northern component to the wind—I have made this mistake, been deposited on my butt, and had trouble sitting for weeks. Not worth it!

Finally, gusty or inconsistent winds may also affect your accuracy because your penetration into the wind can change unpredictably throughout the course of your canopy flight. Remember not to fly over anything you do not want to land on and to err on the side of caution when evaluating where to land.

To summarize, here are some questions you should ask yourself before jumping any day where the winds are gusty or the conditions appear “bumpy” for other jumpers. For an excellent technical discussion of the different kinds of turbulence, take a look at this article from Performance Designs.

  • Does my canopy ride feel typically feel “bumpy” on windy or gusty days?
  • Are other jumpers with canopies loaded similarly to mine either sitting out or, if they are jumping, are their end cells rolling under?
  • What direction is the wind out of? Is it out of the North or another direction that is likely to create turbulence near my intended landing target?
  • Am I comfortable jumping in conditions where it may be more difficult to accurately predict where I will land?

Who sits down and who stands up

Watching other canopies land and asking jumpers about the conditions is one of the best ways to evaluate whether or not you feel safe jumping. Of course, you have to ask and observe the right people. Consider the following.

1. Experienced jumpers sit down because they know they can jump on a better day

Many experienced jumpers have jumped in not-so-pleasant conditions. As a result, many of them are totally over it and are much pickier about the conditions they choose to jump in. This usually because they have experienced turbulent conditions either felt unsafe or just determined that it is no fun to land in sketchy conditions. When long-time jumpers are sitting down, it is typically a good sign that the conditions are bad enough that they are not worth the risk of jumping.

2. Experienced jumpers might stand up because they are very experienced canopy pilots on high-performance wings

Some experienced jumpers, however, may choose to jump in a wide range of conditions because they feel it has very little effect on the canopy that they fly. For example, people with thousands of jumps jumping tiny cross-braced canopies are, speaking broadly, less vulnerable to turbulence. They are also very experienced canopy pilots. If you are a beginning or intermediate skydiver on a larger canopy, do not decide you should jump because these kinds of jumpers are still skydiving. If, however, even very experienced pilots are sitting out—take note! The conditions are very likely not the kind you want to be jumping in.

3. Experienced and inexperienced jumpers might stand up because they are very eager to jump on a particular day

Jumpers who are team training or at the drop zone for a record event might choose to jump in conditions that they would sit out if they were fun jumping. Someone who hasn’t jumped in a long time may also choose to jump in borderline conditions. And many inexperienced jumpers may choose to jump in sketchy conditions because they do not know any better or are still experiencing the initial rush of a new hobby. Jumpers of all levels of skill will experience peer pressure to jump when their friends make the decision to jump.

You can make positive safety decisions that will affect your friends. Often, if one jumper on a load decides they do not want to jump in certain conditions, other jumpers who are too afraid to speak up will join that jumper in sitting down. That decision may impact another group’s decisions about whether to jump or not. Choose to be a positive role model. Choose to be conservative. As many an experienced skydiver will tell you, it is best to be on the ground wishing you were in the sky than in the sky wishing you were on the ground.

By Meredith Regan
Reprinted with permission from FlyLikeaGirl.com