Saturday, June 5, 2010

When Things Go Bad - Part 2

“Climb if you will, but remember that courage and strength are nought without prudence, and that a momentary negligence may destroy the happiness of a lifetime. Do nothing in haste; look well to each step; and from the beginning think what may be the end”.
(E. Whymper, 1865)

In my last post I emphasized the importance of 'pre-thinking' about your reactions to abnormal and emergency situations. I continue that theme in this post. Again, these are all situations that are avoidable. Do your best to use good judgement to avoid the necessity to employ these procedures.
SCENARIO 4 - Off-field landing
Due to circumstances, (blown back, climbed into a position where you can’t make the ‘normal’ LZ, malfunction that requires a quick landing, etc.) you are going to land in a LZ that is not familiar to you. Congrats! You just went XC!
Your decision to choose an LZ should be made at an altitude that allows time to assess the LZ and plan your approach. When you are making your first few out-landings, please give yourself lots of margin. Plan your approach while fairly high. Use large fields. Long and runway shaped (into the wind) is preferable to short and square. Plan to make a pattern similar to the one you are used to. Once your decision to land out has been made, choose the best field you can safely reach using the following criteria:

• Wind direction – Pick a field that allows a landing into the wind.
• Obstructions and crops – Consider rotors downwind of obstructions. Also choose a field without nasty vegetation and expensive crops. If you must land in crops, attempt to minimize the damage you cause by landing near the edge of the field, or on a road within it.
• Slope – This is secondary to wind direction since it is possible to side-hill land or even land uphill. Landing downhill can be problematic and create an ‘overshoot,’ so pick as level and large a field as possible.
• Wires – Assume the field has wires in it and around it. Look for structures adjacent to the field and look for wires to the structure. Also consider fences when evaluating the field. Barbed-wire fences tend to attract wings after a safe landing.
• Livestock – Ideally, you want to choose a field without any animals in it. Failing that, land as far away from the livestock as possible. Horses are particularly skittish so talk to them as you make your approach and make an attempt to avoid over-flying them.
• Extraction considerations – Look for alternative fields if, for example, you notice a river without bridges between you and the road.

While you are looking over your options, consider a secondary field that you may opt for if your primary choice proves, later, to be unsatisfactory due to wires, crops or other factors.

All factors, short of getting yourself down safely, are of little importance. Land safely and then deal with extraction problems, negotiating with angry land owners etc
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If you discover on short final, that your field has wires across your path, you must react quickly to avoid hitting the wires. If the electricity doesn’t kill you, the fall will certainly hurt. Consider these alternatives. Land X-wind or downwind to avoid the wires. B-line stall to increase your descent angle into the remaining space prior to the wires. Pick the softest looking trees, bushes, etc. rather than fly into wires. If necessary, consider your gear as expendable. It is better to shred your wing or harness than to wreck your body trying to save your gear.

Landing ‘off-field’ should become something that is not intimidating at all. I consider it to be a valuable skill that needs to be practiced by everyone. Consult your instructor for the first few, though.
SCENARIO 5 - Knot in your Lines
You launch and soon notice a tendency of the wing to turn to the right. Counter steering and wt. shift are sufficient to fly straight, but you have some serious controllability issues.
First, fly away from the hill to provide ground clearance and time to resolve the issue. Use minimum brake inputs since you may be very close to the stall point. Next, remind yourself (by looking and touching) the location of your reserve handle – If you need to toss your reserve this quick review will serve to minimize your response time. Consider flying over an area that is ‘friendly’ to coming down under your rescue canopy. Also consider that your glide ratio may be degraded by the drag created by the deformation of the wing.   Head directly for your LZ while you assess and try to remedy your situation.
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Now let’s assess the situation. Look at your wing and notice any obvious dimpling of the lower surface. Look for lines that are snagged. Look at your risers to see it the carabiners and speed system are all normal. Use the eyes of your mates to indicate any noticeable defects from above.

You probably have a knot in your suspension lines. Often you can clear a knot by carefully pulling the affected lines and letting them (‘twang”) loose. It may take a few tries – but be cautious, you may cause the wing to spin if you are pulling enthusiastically on one side. Another possibility is that your speed system is hung up on one side. This should be evident by looking at the risers. You might try to activate your speed system (gingerly) to see if that clears the problem.  Another possibility is that your brake line has fouled.  It isn't uncommon to launch with the brakes wrapped in the 'D' lines and this can cause a restriction of the brakes at the pulley.  If controllability to a safe landing is in doubt, consider using your hook-knife to cut the offending brake-line, speed-bar line or rear suspension line.   If clearing the cause of the asymmetry is unsuccessful, then I recommend landing in the largest LZ available. Make your approach as conservative as possible and consider that your controllability may change when slowing for touchdown – even stalling much earlier than normal. Consider landing in a large field without a flare.

An advanced ‘last resort’ technique, which one should only attempt if controllability is really in doubt, and you have a healthy clearance from the surface, is to execute a full stall to release tension on the lines and then pull them tight. If the knot doesn’t come out, the result may be an abnormal recovery/cascade event that will result in a reserve toss.
SCENARIO 6 - Tree Landing
Due to a gross miscalculation, you are going to land in the trees.
Plan your approach so that you impact near the central trunk of the tree. Ideally you should impact with the tree with your legs crossed at the ankles and slowed with a full flare 4-10 feet above the tree branches. Once the noise stops and you complete your string of expletives, assess your situation.

If you are hanging above the forest floor, get secured to the tree. Grab a good branch, then tie on to it as quickly as possible using whatever is available. If there is a possibility of your wing being re-inflated by wind, then do what’s necessary to secure it. I recommend carrying a tree kit (which is accessible while strapped into your harness). It will contain enough webbing to attach your harness to the tree. If you are secure, you might consider waiting for rescue as the safest course of action. If you decide to exit the tree, be sure that you have sufficient equipment to go all the way to the ground - if not, stay put. Some recommend using the reserve parachute lines and bridle to climb down from the tree – I wouldn’t recommend using this method higher than you care to fall.

You can decide your options based upon the gear you have accessible, your situation in the tree, and the distance to the surface. Options to consider are: rappelling from the tree (anchor) while in your harness; rappelling from the harness (anchor) using a separate climbing harness or diaper harness; or even climbing down the tree.

HERE is a great article that explains the hazards and methods of extracting yourself from a tree.
At the very least, have a spool of dental floss in your pocket to lower to the rescue crew. It can be used to pull up a climbing rope.

I highly recommend practicing with your tree kit under controlled conditions. It is trickier than it looks to rappel from the tree and rig the harness for rappel.
SCENARIO 7 - Water Landing
Due to a gross miscalculation, you are going to land in the water.
Just as is a ditching in my airliner, this is a nightmare scenario. The following applies to any water landing, but is particularly true in any type of surf. Your chances of death, when landing in the midst of 30sq. meters of sail and 300+meters of spectra lines, is quite high. You should do everything in your power to avoid a water landing - almost any other scenario is preferable to landing in surf.  This includes crashing in an unsavory place and risking injury. Bear in mind that I am a strong swimmer and this scenario is still VERY intimidating because the gear you are wearing; helmet, boots, multi-layers of clothing - all soak up many pounds of water and will effectively exhaust and drown you. . .

That said, you can do a few things to improve your chances of survival:
  • Carry a hook knife and keep it readily accessible.
  • Once it is obvious that you will be landing in the water, plan your approach so you will hit close to the shore in a (preferred) downwind direction. 
  •  By flying downwind, you are assured that the wing will overfly you and not come down on top of you.  
  • Prior to landing, at an altitude of about 50’, you should remove the brake loops from your wrists, disconnect your leg straps and chest strap, and remove any cockpit attachments (if you think they will hinder your evacuation of the harness). 
  • Plan to fly into the water with no flare, to allow the wing to overfly you. Simultaneously rock forward out of the harness, dive down and escape laterally (towards shore) so as to avoid any lines.
  • Rid yourself of clothing and footwear as soon as you are clear of your lines - You are going to be exhausted in an amazingly short time. 
  • Forget about saving your gear until your safety is assured and you have help. It is amazing how heavy a wing full of water is. If you don’t believe these cautions, watch the video below.



More scenarios at When Things Go Bad Part 3 -
Fly Safe out there.
Tim

7 comments:

happyidiot said...

... nice tips and good reminders.

FYI ... in high wind landings I have SOMETIMES found a high, strong pull on the "As" works to kill the wing, while pulling on the Cs will tend to pop the glider and force a run back to some place you don't want to go, say, the edge of the bluff. Again ... high wind only ... wing's pressurized ... maxed angle of attack ... little room for run ... and brake/Cs will quickly increase lift before stalling.

Wingnut
Santa Barbara, CA

Tim O'Neill said...

Thanks for the note - H.I.
I forget sometimes that other wings don't respond like mine does. Killing with a frontal; Killing with an 'A' on on side and 'D' on the other also can sometimes be effective. Fly safe -
Tim

Dizzy said...

Here is a table with efficiency for different methods:

http://expandingknowledge.com/Jerome/PG/Skill/All/J_Tips/English.htm#Wing_Kill

Kurt said...

Tim,
Great to see you collecting thoughts on safety. I think many pilots can benefit from access to this sort of information.
Some notes on water landings, especially into surf: -Helmets often have cloth linings that quickly become waterlogged and prevent one from lifting one's head above water. Get that helmet strap undone before you go in.
-Clothing stretches when wet and so gloves will hinder movements of fingers, jacket and sweater sleeves will extend over the hands rendering them clumsy, and all wet clothing will be difficult to remove.
-Those great ankle-protecting boots you are wearing will quickly become cement shoes when you try to swim.
-At the coast your definition of 'surf' should include wet sand and rocks along the shore. Pilots have been killed by having their wing pulled in by a wave with them still attached, and this scenario unfortunately repeats all too often.

This info is gleaned from observations of those who have gone in the surf and lived to tell about it.
Another thought: Not many situations are going to give you enough time (50') to 'get ready' to go in the water. You will be spending that altitude trying to avoid the water landing, and you should. When you mention avoiding "at all costs" people should realize that means that crashing into just about anything else will likely be safer that the waves.

In winter of 2009 we had a pilot drown at the Dump in Pacifica. No one witnessed the incident so we will never know exactly what happened, but when the body was found the boots and helmet were off and the pilot was fully out of the harness, entangled in lines. That information paints a very scary and grim end to his life and it's tough to think about, but it highlights the point I'm trying to make, which is that landings in moving water are really NOT an option to be considered in the same way tree landings are, or being blown over the back. They are more in the same category as crashing into high voltage electric lines. Best to prepare for how one will never let it happen.
My $0.02

Tim said...

Good stuff Kurt. I'll edit the post a bit to reflect your inputs.
Thanks!

Claudia said...

Hi Tim, I’m revisiting this blog topic coming from your recent post @ pgforum. Great read for the second time. A note on the knot topic: we had an accident this year when a pilot launched with a knot/cravat, flew out very carefully to the LZ without problems, but when he turned (gently) to land the wing spun and he broke his back. It may be a good idea to avoid turns close to the ground if a big area of the wing is affected by the knot/cravat.

Tim said...

Hi Claudia - Sorry to hear about the accident. Thanks for your reminder.

It's very easy to stall/spin when the lines are fouled. Any approach should be made with minimum inputs and consider making a no flare landing.
Tim

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