'Sinking in' a canopy...

[Yossarian 0]

During a general conversation about downsizing and canopy choices and was receiving some advice about getting the most out of ones canopy and being able to handle it well in all situations before even considering downsizing (good advice i believe!). One thing that was mentioned was knowing how to sink a canopy into a tight spot. Then the load went on a call and the font of knowledge had to go kit up. so my question is, how is this done? obviously ill go and talk to an instructor before i try this, but as far as i can gather its flying an approach on half to deep brakes in order to reduce forward speed and come down a little faster, the point being to land in a perhaps confined space.
by the way i fly a pilot 168 loaded at just over 1

thanks for any explanation, and like i said ill always go to an instructor first...

[phoenixlpr 0]

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obviously ill go and talk to an instructor before i try this, but as far as i can gather its flying an approach on half to deep brakes in order to reduce forward speed and come down a little faster, the point being to land in a perhaps confined space.
by the way i fly a pilot 168 loaded at just over 1

I did the same with Navigator 220. I got an ankle surgery. Good luck!

[wmw999 2,116]

It's a skill to learn, like any other. Some canopies lend themselves to being sunk in better than others, and most landings are going to be harder. Expect to PLF.

But it's a good emergency skill; the occasion where you HAVE to swoop doesn't really occur. But you might just end up in a situation where, on a bad spot or a reserve, you do need to sink a little bit into a tighter spot.

But accuracy training in general will also reduce the need to sink. So talk to someone about canopy training in general, not just for standups and swooping.

Wendy W.

There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown)

[Yossarian 0]

yeah, will do. ive just been told its something you should do a few times, like landing on risers (havent tried that yet either)

[davelepka 4]

Sinking a canopy in is an old, old term that came about when most canopies were seven cells, and accuracy was the 'in' thing to do.

Many large seven cells have very low forward speed. What this means is that when you have a headwind that equals the forward speed of your canopy, your ground speed is zero, and you are sinking your canopy straight down.

This related to accuracy because the technique in competition accuracy is to come in high, and once over dead center, sink down on top of it. The reason being that you can come in 100 ft high, and sink straight down onto the target, but if you come in even 5 ft low, you'll never make the target.

Another factor at work here is the size of the cells, and how far the topskin overhangs the bottm skin at the nose. Some of those old canopies had so much overhang that even in still air they could almost fly backwards. The overhang of the topskin could catch enough air to maintain some inflation with no forward speed at all.

All of the above explains why accuracy competitors still jump canopies desinged 25 years ago. All of the improvements to canopies would not help them with the techniques they use. This is also a good time to point out that accuracy competitions use a giant pad, called a tuffet, to land on. While sinking the canopies in, even a 240 sq ft canopy will drop you pretty hard with this technique, and it is not the way to get the softest landing.

On to the present day, you will never sink a modern canopy in anywhere in an emergency. The reason being is that the high stall speed of a modern canopy means that you would need a strong steady wind to be able maintain a clean sink. When jumping in these kinds of winds, the last place you want to be is landing in an area where you cannot simply let the canopy fly, and use a normal approach.

Heres the important part - whatever is causing your chosen landing area to be so tight that you want to sink it in, is also working with that strong steady wind to cause object turbelence, and when your canopy hits this turbulence, bad things will happen. The problem is compounded by the fact that you're in a braked configuration which puts your canopy closer to the stall point.

When jumping in higher winds, landing in a area free of upwind obstructions is key. Additionally, with all that wind the accuracy of the spotting becomes less and less important. If you can get open within a mile upwind of the DZ, your modern canopy, though bad for sinking, is great at floating you back home, so you can land at the DZ.

You can fly a braked approach with your canopy if need be, which will get you into an LZ with less forward speed, but you'll trade off that speed for less lift during the flare, and you'll come down harder than ususal.

Most modern canopies can be landed in a very small area from a full flight approach. Many people use a two step flare, in which the first step levels out the canopy and gives them a little surf, and the second step will slow it down before they put their feet down. This is fun, but it takes up 20 or 30 feet of real estate.

You can use a single step flare, in which you flare a touch higher, and touch slower, which will kill a bunch of your forward speed, but still offer you reasonable arrest of your descent for a soft landing.

I think the overriding concept here is that old canopies could sink right into a tight area surrounded by trees. They also couldn't glide very far, and it was common to open them at or below 2000ft.

Take advantage of your newer canopy, with it's excellent glide capabilities, be smart and have it open by 3000ft, and you'll have the luxury to usually just land on the DZ. When you can't, your canopy can fly you to such a large range of options for places to land, that you can select one that will allow you to fly a standard, full flight approach.

[Yossarian 0]

that was all very interesting, thanks very much!

[Zenister 0]

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most landings are going to be harder. Expect to PLF.

being confident you can do so without hurting yourself helps alot...

Practice these until you are confident in your ability to do them... its only dirt.. it washes off easier than blood...

____________________________________
Those who fail to learn from the past are simply Doomed.

[riggerrob 558]

... its flying an approach on half to deep brakes in order to reduce forward speed and come down a little faster ...

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Correct about forward speed, but incorrect about vertical speed.
When you apply brakes, you normally reduce the vertical descent rate more than horizontal speed, ergo the canopy glides at a steeper angle.

This technique can be used with any canopy a couple of hundred feet up. However, canopies should only be "mushed in" if they are huge accuracy canopies (i.e ParaFoil or Eiff Challenger Classic) if they are specifically designed for precision landing competition.
With modern sport canopies, use a braked approach up high, but "let it fly" for the last couple of hundred feet. Let's face it, if you are not aimed directly at the target - by 200 feet - you are never going to hit it. And getting all toggle-monkey will not salvage a bad approach ... so just do a regular flared landing.

In conclusion, discuss braked approaches with a local instructor and practice them up high, in preparation for landing "out" in a tiny back yard. Just be mentally prepared to "let it fly" the last couple of hundred feet, and do a normal flared landing.

[davelepka 4]

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Correct about forward speed, but incorrect about vertical speed.
When you apply brakes, you normally reduce the vertical descent rate more than horizontal speed, ergo the canopy glides at a steeper angle.

This is correct, however I want to make it clear that your descent rate in partial brakes will be higher than it would be at the end of a normal flare. If you were to fly in half brakes straight into the ground, the impact would require a PLF.

Additionally, your descent rate at the end of a flare that started in half brakes will also be higher than if you had flared from full flight.

Ideally though, the rest of the post is correct, and you should have your canopy flying straight and at full flight well before begining your flare.

[pilotdave 0]

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When you apply brakes, you normally reduce the vertical descent rate more than horizontal speed, ergo the canopy glides at a steeper angle.

I think it's important to point out that you only get a steeper glide when you have some wind. In no wind or downwind conditions, brakes will make your glide shallower on a modern canopy. I think people sometimes hit their brakes on final when they think they're going to land long... in light wind, this can make them go farther. You can't steepen the glide of a modern canopy in no wind conditions by using brakes... until you stall.

Dave

[DrewEckhardt 0]

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One thing that was mentioned was knowing how to sink a canopy into a tight spot.

By the time you get a big F111 seven cell to 2/3 brakes the glide ratio has dropped to 1:1. At a good wingloading (arround .7) you can come in at 3/4 brakes, flare a bit, and have a comfortable standup landing. Furthur brake application will bring you nearly straight down although the landing will be harder.

By the time you get a modern canopy to 2/3 brakes it's got its best glide ratio above 2:1 and there's a fine line between worse glide and stalling. While a half brake approach will give you enough airspeed to produce a decent landing from a well-timed flare, it's going to be hard.

The equipment has changed.

It _is_ a good idea to fly a braked approach. You can come in steeper with a head-wind, have more time to think about things, it's easier to make flat turns, etc; but you aren't going to get a classic sink out of a modern canopy.

[riggerrob 558]

We seem to be confused about the notion of how much brakes to apply.

Most of my comments - about "sinking in" were related to flying in 3/4 brakes, in a classic accuracy competition approach. Admittedly a mode that many modern canopies are not comfortable with.

You - on the other hand - seem to be talking about flying in 1/4 brakes.
Yes, 1/4 will flatten the glide on some canopies. Heck! 1/4 brakes flattened the glide on my Cruislite 220.

[billvon 2,380]

>but you aren't going to get a classic sink out of a modern canopy.

Well, you can, but:

a) you'll be so close to stall that you won't dare flare

b) your descent rate will be very high and

c) you canopy will not be that stable (read: hard to control)

That being said, there's a method I've called a "jennifer landing" that's often used to land tandems that can be used to pull off a steep approach. In this sort of landing, you get in deep brakes and sink the canopy into the landing area. At X feet you get off the brakes smoothly. The canopy drops and surges and tries to recover its forward speed; during this time the canopy is descending very steeply. At the bottom of the arc you have recovered your original speed (plus a bit more) and land normally.

I discovered this accidentally while trying to land in a forest clearing years ago. It was quite tight, so I set up a pattern coming as close as possible to the trees on the near edge. I miscalculated and it looked like I was going to hit the trees. I flared just enough to clear the trees, then went back to full flight. The canopy dropped like a rock, and barely recovered before I had to flare for the landing.

When I looked around, though, I realized I had landed very close to the near side of the trees. Had the clearing been smaller I still would have been OK.

Problems with this are:

a) finding that X feet is tough

b) if you do it too low, you're royally screwed. Your canopy is now diving at the ground at a vertical speed with a low airspeed, so you've got no flare power to arrest your descent.

c) if you do it too high you're also screwed because you will recover with _more_ airspeed than you started with - this will give you a better glide angle (momentarily) at the exact moment you need a steeper glide angle.

All in all I don't recommend it without a LOT of practice.

[pincheck 0]

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that was all very interesting, thanks very much!

speak to Mike Gorman at your dz and get on a canopy course

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[pilotdave 0]

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You - on the other hand - seem to be talking about flying in 1/4 brakes.
Yes, 1/4 will flatten the glide on some canopies. Heck! 1/4 brakes flattened the glide on my Cruislite 220.

No, I'm talking about deep brakes. You'll flatten the glide of most canopies right down to near the stall point. Like billvon said, you won't reach a point where your canopy is sinking (in no wind/downwind) until it's really close to stalling. Flying nicely in 3/4 or even full brakes on some canopies is not that point.

It's all taught in Scott Miller's Essential Skills Course, and he makes you prove it to yourself on a long spot.

He teaches braked approaches in the advanced course... using brakes to steepen or shallow your approach. The effect is opposite in higher winds than in light wind (or no wind or downwind).

Dave

[Yossarian 0]

yeah ive spoken to him about getting on a course, didnt have the money in time for the august one though. was thinking of doing it through the autumn when sometimes a low lob is all there is to be had anyway