Skydive SAFETY – The CRUX
Dan's Dan's Thought for the Day...
Learning to consistently achieve comfortable stand-up landings can be particularly challenging and frustrating for many new jumpers, especially on nil wind days. Even experienced jumpers who are usually satisfied with their landings may recognise that their zero wind landing skills need improvement.
You may get lots of information on this topic by listening to jumpers at the drop zone or looking on the Internet but you may not always find that advice easy to follow, or it may not be suited to your particular needs.
Here, we will examine some advice you may encounter while working to improve your landings, and see why it may or may not help you achieve the results you desire. Hopefully you’ll find some answers here – but the more important goal is to encourage you to continue asking questions.
Learn to relax and stay focused if you do flare high; keep flying the canopy and finish the flare
Many jumpers believe that flaring too high is one of the worst mistakes a person can make while landing. For some 'the game is over' the instant they realise they have made this mistake; they expect the worst, stop flying, and start panicking.
In an effort to avoid this mistake some jumpers develop a habit of consistently flaring too low. Another common problem occurs when people reach for the ground with their feet, trying to get themselves back on earth while the parachute is still holding them a few feet above it. People who suffer from these habits are often pleasantly surprised, and see a remarkable improvement in their landings, when they learn that it is not actually necessary to level off with your feet right at ground level. Many canopies are very forgiving of a high flare.
People can worry that their canopies might stall if they flare too high. Taking a closer look at the concept of a stall can help us understand why this is not necessarily as big of a problem as some might think.
‘Stall’ has a very specific meaning in aviation. It is a significant decrease in lift caused by a separation of airflow that occurs when a wing reaches its critical angle of attack. Understand?
No? Okay, imagine a car driving down the highway, heading toward a curve in the road. Most highways have gentle curves, for good reason, because cars tend to fly off the road if a curve is too sharp. Now think about the relative wind blowing in your face under canopy. Your canopy bends that relative wind to create lift. Pulling down on both toggles pulls the tail of the canopy down and bends the relative wind even more, creating even more lift. The further you pull the toggles down, the more lift is created, up to a certain point. The ‘critical angle of attack’ is the point where the curve becomes too sharp and the relative wind separates from the canopy like a car flying off the road. This separation results in a sudden and dramatic loss of lift. The term ‘stall’ refers specifically to the sudden loss of lift that occurs in this particular situation.
The test jumper puts the canopy into brakes, pulling the tail down and increasing the curve that the relative wind must follow. This continues into very deep brakes, but not yet into a stall.
With further pulling down of the brakes, the canopy reaches the critical angle of attack… the lift rapidly decreases as the canopy begins to stall… you can see the dramatic moment the canopy stalls.
Full stall demonstration, with toggles. Canopy is a PD Silhouette 210. Exit weight is approximately 220 lbs.
When flaring it is obviously important to have your feet on the ground before your canopy stalls. But let’s think about a student parachute. Student canopies are traditionally not supposed to stall when the toggles are held all the way down in a full flare. They are either designed that way or rigged with extra slack in the brake lines.
What about a slightly smaller canopy, one for a novice or intermediate? If the brake lines are set to the correct length specified by the manufacturer, many canopies in this category also will not stall when the toggles are held all the way down in a full flare.
They will simply maintain a slow forward speed and low rate of descent, just like we see in this image of a novice landing a canopy.
Even if they do stall, it might not occur until the toggles have been held all the way down for a number of seconds: sometimes five or six seconds, maybe even more. Jumpers who fly these types of canopies don’t really need to be too concerned about an accidental stall.
You may be surprised to learn that some small, high-performance elliptical canopies also will not stall with the toggles held all the way down, or at least not until they’ve been held there for a few seconds.
Whether a particular canopy will stall when it is held in a full flare depends on several factors such as the model and size of the canopy; the length of the brake lines; the length of the risers; and length of the jumper’s arms.
When held in a full flare a significant number of canopies will simply maintain a relatively low airspeed and rate of descent, at least for several seconds. This knowledge can be very helpful when we talk about flaring high. Look at the next video. In the beginning we see a jumper reaching level flight with his toes about six feet above the ground. Tragedy? Not really. There are only three things he needs to do:
The jumper starts flaring high, but he responds properly and finishes with a good landing. Canopy is a PD Sabre2 170.
‘Wait’ means stop pulling the toggles down as soon as you realise you’ve started flaring too high. Save the rest of the flare for later. ‘Keep it straight’ is important. Look at a point on the ground out in front of you and keep the canopy flying straight toward that point.
When the canopy starts to drop you back toward the ground, just before your feet touch down, push the toggles down and FINISH your flare, as we see in the video.
In most cases doing this will result in a reasonably soft, stand-up landing. Even if you don’t land softly, look at the jumper's body position when he finishes the flare. Looks like he's ready for a PLF, doesn’t it?
Granted, you’ll achieve softer landings on nil wind days if you level off just above the ground but that skill must be developed through practice. Learn to relax and stay focused if you do flare high, keep flying the canopy and finish the flare. This will improve your landings in all conditions.
We can see the importance of knowing whether or not your canopy will stall when held in a full flare. How can you find this out? Yep, you guessed it: under canopy! In your holding area, above 2,000 feet, after checking thoroughly for other canopies, push those toggles all the way down and see if that baby stalls. If you’ve never stalled a canopy before ask some advice from an instructor or coach before trying it.
So… Did your canopy stall? No? Makes flaring seem a bit less intimidating, doesn’t it? Or was the canopy easier to stall than you expected? If so, you may want to have it checked out by a rigger. Some canopies are relatively easy to stall, even with the brake lines set to the correct length. If you are jumping one of these canopies then hopefully you’ve already perfected your landing technique under something more forgiving.
If you can’t stall your canopy just by holding the toggles down, does that mean you won’t be able to get enough stopping power at the end of your flare? Some people believe so but in reality there usually isn’t anything wrong if your canopy does have a bit of extra slack in the brake lines.
Even with the brake lines ‘de-tuned’ on a student canopy, we still expect students to learn how to stand up their landings. In fact, many popular canopies used by experienced jumpers will also slow down enough for a comfortable landing even if you cannot reach the canopy’s absolute slowest flying speed. Plenty of people achieve soft stand-up landings in calm winds under canopies that will not stall when the toggles are held in a full flare. Even jumpers who have intentionally lengthened their brake lines for swooping can still achieve comfortable landings in calm winds.
Is there anything wrong with shortening your brake lines? In some cases, yes! Especially if they are shortened so much that they pull the tail down when your toggles are in the full glide position. As an example, look closely at the tail of this canopy.
It seems like the jumper is pulling the toggles down slightly, but a closer inspection shows his hands are all the way up. Having a canopy’s brake lines set too short like this can significantly reduce the flare power on some canopies and make them noticeably more difficult to land, particularly on nil wind days. Excessively short brake lines are more common than many people realise and frequently go unnoticed. The brake lines shrink during the canopy's life, so they can gradually become too short. It is a common mistake for someone to shorten a canopy’s brake lines because it appears that the canopy ‘doesn’t have enough flare at the bottom end,’ when the real problem is that the brake lines are already too short!
If you’re really convinced that your brake lines are too long, there are a few steps you should take before having them shortened. On your next jump, after you’ve released your brakes, put your toggles all the way up against the guide rings and look up at the tail of your canopy. Remember to watch where you’re going and look out for other canopies. If your canopy looks like the one above then forget about having the brake lines shortened. They probably need to be lengthened instead.
If your canopy seems difficult to land you can also have a rigger measure the suspension lines and compare them to the manufacturer’s specifications. It’s possible that your canopy has simply gone out of trim and is due for a reline.
Once these steps have been completed then get some of your landings videotaped and see if you are finishing your flare properly. Look at the jumper in this video, just as he is touching down.
Flaring Problem - Raising Toggles on landing. The jumper lifts his toggles just before touching down, resulting in a harder landing than necessary. This is a common problem, caused by a natural reflex: the tendency to reach our arms up and out for balance when we jump off something. Many jumpers do this to some degree when landing. You might have no idea you are doing it until you watch yourself on video!
Does he need shorter brake lines to get a better flare? No, he needs to push his toggles all the way down and finish flaring before he touches down. Most jumpers finish their flares at least slightly better than this jumper, but not finishing completely is one of the most common flaring problems.
Not finishing completely is one of the most common flaring problems
If you are still absolutely convinced that you need shorter brake lines then they should only be shortened by an inch or so at a time. Make several jumps, preferably in different wind conditions, before shortening them any more. And remember that you can significantly reduce a canopy’s flare power by shortening the brake lines too much.
There is usually some excess brake line left over when the toggles are tied onto a canopy – and there are front row seats in purgatory for people who cut this excess brake line off! That excess line should be finger-trapped back into the brake line or secured in a similar fashion in case the brake lines need to be lengthened later on. A qualified rigger should know how to do this correctly.
Banking or turning at some point during the flare is a common problem that can be exaggerated on nil wind days. Banking or turning during the flare is most commonly caused by reaching for the ground with one foot. You can usually see yourself doing this on video and might even feel yourself doing it while it’s happening. This problem can easily be avoided if you focus on looking straight ahead, keeping your body straight, and flaring evenly. The jumper in this photo is reaching for the ground with his right foot, pulling down his right hand and inadvertently initiating a turn. He probably thinks he was caught by a side gust.
Some people worry about exactly what their feet should be doing while they flare. If you feel the need to think about your feet, it can be helpful to just think about keeping them together as you get into level flight, and continue keeping them together while you fly the canopy in a straight line across the ground as far as possible. If everything is going smoothly then as the canopy sets you down you can stand up as if you were getting out of a chair. Your feet know what to do!
Look at this video. We see a jumper flaring his canopy with his feet and knees together, knees slightly bent. Looks like he’s simply maintaining a good PLF position, doesn’t it? As he finishes his flare and the canopy sets him down, his feet come apart slightly to accept his weight.
Good Flare Technique. The canopy is a PD Spectre 190, exit weight approximately 160 lbs, jumper has approximately 60 jumps.
There is often discussion about the benefits of leaning forward in the harness. Is this really a crucial part of flaring? Look at the video again. The nose of the canopy tilts up at the beginning of the flare, known as a change in pitch. This pitch change is what puts the canopy into level flight, and the change is actually created by the movement of your body under the canopy. In fact, it can be extremely helpful to view your body as an integral part of the parachute system.
Keeping things simple, letting yourself relax, and focusing on good basic flaring techniques will go a long way to improving your landings in all conditions
For example, feeling your body swing in conjunction with the canopy’s movement is an important part of doing effective practice flares. If you like to lean forward in the harness and it seems to help your landings, that’s fantastic. It feels nice and looks cool. But it’s also not a problem if you simply sit still in the harness and let your feet swing out slightly in front of you as you flare. Your body will rock up onto your feet as your feet touch down and accept your weight. Whichever one feels more comfortable is the best technique for you.
In general, it might help to stop thinking about a ‘nil wind' landing as being significantly different from a ‘normal’ landing. The basic skills that you use to land in stronger winds will also help you land softly in calm winds. Any bad habits you develop might not hurt your landings too much when there is some wind to slow you down, but those habits are usually still present and affecting your flare to some degree and can be eliminated by practising proper techniques.
Eliminating those bad habits by keeping things simple, letting yourself relax, and focusing on good basic flaring techniques will go a long way to improving your landings in all conditions. Soon you’ll be just as confident landing on calm day as you are on windier ones, and you may even start to prefer nil wind landings.
The most basic principles of aerodynamics can be used to describe the flight of any wing, so some of the things you learn about one canopy will certainly apply to others. However, specific performance characteristics can vary greatly with size, and from one model of canopy to another.
Experienced skydivers, including instructors and coaches, develop their own opinions, philosophies, and teaching methods – as in any sport. The advice you get from one person may be quite different from what someone else tells you. Although potentially frustrating, this can be a good thing, because the advice that helps one person may not be equally helpful to others.
When discussing canopy performance and flying techniques the most important piece of advice is this: don’t passively accept anything anyone says, (including me). Think about it and, if it doesn’t make sense to you, keep asking questions until it does. More importantly, experiment in the air and see for yourself if it’s really true.
Article, videos and uncredited photos by Scott Miller