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I overshot a target in Gran Canaria last year; ended up flying thru a gap in some trees and down a small track where I crash landed into some bush; no damage/injuries. My mate did a bit better in that he also overshot the target, flew down the same track but managed a stand-up.

It was dark, hardly any wind and the LZ was tight but not that tight and I should have sunk it in vertically (BJ280) but I bottled out mainly because I haven't practised steep, vertical deep brake landings enough. My bad!

So I've been thinking about getting a good deep brake canopy with Slats i.e. OSP etc. but then I was wondering if anyone other than Accuracy Jumpers ever really sink their canopy all the way in? Obviously over the years I've watched tons of our Base movies and I can't remember ever seeing anyone sinking their Base canopy all the way in to the ground.

I'm not in so much touch with main stream jumpers so I want to ask:

1 - Do any of you guys actually touch down in deep brakes (when the LZ is super tight)?

2 - How are your landings because even competition accuracy jumpers use a Pea Gravel Pit and they still rock & roll; they don't do the tippy toe landings that I often hear about. So how are your landings when you touch down in deep brakes?

3 - Does anyone have any Base videos of these types of landings?

Thanks in advance…

John

> 1 - Do any of you guys actually touch down in deep brakes (when the LZ is super tight)?

Yes. And flaring from deep brakes gets pretty tricky.


> 2 - How are your landings because even competition accuracy jumpers use a Pea Gravel Pit and they still rock & roll; they don't do the tippy toe landings that I often hear about. So how are your landings when you touch down in deep brakes?

In my experience, canopies with slats give much better deep brake flare (probably because the slats maintain more lift generation at lower airspeeds). I'd look at those canopies if you think you'll need this characteristic a lot.


> 3 - Does anyone have any Base videos of these types of landings?

I'll see if I can dig some out for you. We practice these landings in our Landing Skills Course, so I should have some on the classroom computer.

Tom,

Typically how are your landings when you touch down on a slated canopy in super deep brakes? PLF, Stand-up?

(Ive just had a hip replacement)

I'd say in deep brakes, straight to flare, you are standing up less than 50% of the time. If you are trying to protect your hip, I'd recommend just PLFing every time to reduce the chance of injury.

A lot of the "trick" to getting the flare from deep brakes is just to punch it all the way out and hold it.

If you are looking for the absolute softest landing from deep brakes, I'd rate the best deep brake flare in order (by canopy, from best) as Vision, Hayduke, OSP, Outlaw, so in your case I'd say you ought to try to demo a Vision and see how that flares for you.

I know it's unlikely, but if you're in Twin Falls at some point I can get you on all four of those slatted canopies to try them out.

I've had to sink it in on occasion, and for a while I was purposefully sinking it in on sandy/soft LZ's for practice. (And 'cause it's fun). Usually I don't flare and just sink it.

I'm a huge fan of the PLF, and use it, or a modified roll, as a default landing whenever things aren't going to plan. However, I have a round canopy background that included 2 weeks of ground school, with 100's of PLF's.

My advice would be a slatted canopy, lots of practice rolls on the ground, and armour up for practicing under canopy. Sturdy boots or PAB's (Parachute Ankle Braces), and hip pads.

For a straight down, to slightly forward PLF, Keep your feet and knees together, slightly bent, with your toes pointed at the ground, and twist at the waist to expose your side. Keep your arms in, don't crumple at the knees, and stay tight, roll over your hip and back.
If I have excessive forward speed, I land feet apart, tuck, and do something like a parkour roll or somersault.

Here's my compilation of interesting landings, with a few PLF's on there: https://vimeo.com/200280319

This^
The lift we generate in a flare is due to the fact that as the canopy slows our weight pendulums forwards which increases the AOA of the parachute which provides the temporary increase in lift necessary for a soft landing.
This is obviously tougher from deep brakes as the canopy and suspended load are both already flying very slowly without much toggle stroke left to create the pendulum. So from very deep brakes you really need to punch out the last of the remaining flare to get the benefits of AOA change.
My personal approach is always deep brakes into a stall surge if possible. That way you are always practicing the "sight picture" of the deep brake approach without having to land from deep brakes every time.

I often flare from deep brakes, I punch it hard. Stand them up most of the time, it feels like jumping off of a 3' bench. Also, having a light wingloading helps

 
My body weight is 175ibs therefore Rays Rule suggests a 280 sq ft canopy but when I tried sinking vertically on my BJ 280 I could not stop the forward speed without stalling.

What ratio of suspended weight to canopy square footage do accuracy jumpers reccommend?
(perhaps I should ask Sky-Dive .com)

Can the new slatted canopies Sink Vertically like this?

https://youtu.be/Fbhg9clQWPk

Do Accuracy Canopies use slats and flaps?

They still use frap hats?

A lot of us here in the land of tight landing areas use OSPs and if you practice enough we can get our canopies to almost drop straight down using the 'teabag' method of which is stalling the canopy then letting it drive for a split second. Keeps inflation and stability while basically on the stall point.

Last week we were messing around and were able to make both the Outlaw and Vision fly backward (PC was toward the nose and pressurized, indicating canopy with negative airspeed) while maintaining pressure.

We also have Haydukes and OSPs available, but I imagine the results will be achievable with all four canopies.

 
What wing loading do you guys advocate nowadays for Vertical Deep Brake landings?

Tom if my memory serves me I think you mentioned you had upsized for such jumps to somewhere around a 0.6 wing loading?

Any luck with the videos Tom ?

Thanks !

Honestly, I'd go with the lowest possible wing loading for those kind of tight, technical landing areas. I have never wished for a smaller canopy over my head, but I've often looked down at a bad LZ and wished for a bigger canopy.

shorehambeach,

https://youtu.be/Fbhg9clQWPk

They are not Base videos but they really gave me a good idea of truly sinking it in and the significant impact forces reflected back into the jumper. In Base of course we are not over pea gravel/accuracy pads, rather we land on concrete roads and hence endeavour to do the final "Punch" type flair as advocated above.


On a seperate note - I've now got all the answers to my questions proving that this forum really can be a very useful resource.

Thanks to all the above contributors,

John

Not that I know of. The most common modern classic accuracy canopies being used these days are the PD Zero, the Parafoil Gold and the Parafoil 2000. None of these have slats or flaps. One of the brands has two vents on the bottom skin but I can't remember which one. The Parafoil Gold comes with the option of easily hot-knifing part of the sewn-in stabilizers where they connect to the canopy. It's only about 12 inches long and I believe it's to make deep brakes a little lighter on the arm muscles.

Is it that Slats and Flaps are relatively new to mass produced Base canopies and the Accuracy canopy manufacturers haven't caught up as yet or is it that we really don't need them to achieve vertical landings as are being achieved in the Accuracy world?

Tom,

I understand that lower wing loads yield a reduced ability to penetrate wind but actually how sluggish is a canopy loaded at 0.65 or does that depend on Wing Type ie OSP vs Vision?

It depends _a lot_ more on canopy type than on wing loading.

A Vision loaded at .55 is still going to penetrate better than an OSP loaded at .75. I'm using those as examples, but it's generally true for high and low glide canopies.

Aerodynamically (in theory--reality is slightly more complex), glide is not changed by wingloading. You just proceed down the same glide slope at a faster rate.

The other thing to remember when trying to achieve penetration on a low wing loading is that front risers will increase your airspeed, and therefore your penetration. You can achieve a lot more penetration (on any canopy at any wing loading) with skillful piloting. It's not just a case of picking the canopy and then accepting whatever it gives you.

Also remember that some canopies are a lot less responsive to front riser input (I seriously feel like I can do pull ups on the front risers of the Outlaw without substantially changing it's flight), and some are more so (the Hayduke, by contrast has very aggressive front riser response and can pick up a lot of extra speed/penetration if the pilot demands it).

Thanks Tom,

As always its complex.

I currently jump a BJ280 with a WL of 0.71 which on the odd occassion I find a tad too fast especially when its a tight, night, windless LZ.

A ton of people, you included, have recommended an OSP as quite a bit of my jumping is on solid objects but I'm in a quandry on WL.

The OSP is a slower wing so perhaps I stay at 0.71 on a 280 or should I get a 300 with a 0.65 WL.

You mentioned you prefer more rather than less fabric over your head but do you think that 0.65 on an OSP is going to be too sluggish?

What would you do?

Personally I'd take the OSP loaded at .65, especially if the intended purpose is tight landing areas in zero wind.

That's especially true if you are keeping the Blackjack, which has very good glide and penetration. The two (BJ at .71 and OSP at .65) will complement each other nicely.

I'm sorry I don't know the answer to that.

I've only seen accuracy canopies come down vertically when there is enough wind, never in NZ. We always have a tuffet or pea gravel pit so it doesn't matter if you hit hard, as long as you land on the tuffet or pea pit.