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14. Emergency Situations, Avoidance & Solutions |
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Author: Jerome Daoust
Homepage: www.expandingknowledge.com (includes pics and movies)
Dragged by your wing. If you get dragged on the ground by your wing in strong wind, grab only one riser (ideally a "B") and reel it in towards you until the wing becomes like a flag. To prevent being dragged in the first place, see Wing Kill.
Water Landing. This is not an exact science; don't listen to those who pretend it is. If there is a current, without quick release buckles, a Tree Landing is preferable. If you want to jump out of your harness : - It is not recommended because it is very difficult to judge your altitude over the water (to help : Don't look down, look instead at the horizon). See Image: Water landing - Pilot jumps out of harness.
- 3 m (10 ft) is an ideal jump height.
- Resurface and look to see if your wing and lines are falling over you, in which case, dive and swim away.
If you remain in your harness : - Unclip the chest strap(s) and one leg strap in preparation. The remaining leg strap will prevent you from falling out by accident. Quick release buckles are encouraged, as square buckles are difficult to undo under tension.
- In light winds, try to fly downwind and do not flare, so the wing overshoots and keeps lines stretched. The leading edge will hit the water first and remain air filled, standing on the water like a wall and be a signal for those at shore. The wing will catch the wind and drift away from you.
- Back protector influence :
- 12 cm foam : Only small pilots will have difficulty keeping their head above water.
- 22 cm foam : Difficult to keep your head above water.
- Airbag : Nearly impossible to keep your head above water. Unzipping airbag for activity over water is recommended.
Adapt your equipment to your typical flight conditions. Once tangled in lines it is nearly impossible to become untangled. If caught in the lines and under your wing, use your hook knife, look for an air pocket. Try to avoid kicking motions to reduce further entanglement. For rescuers : Don't jump in the water before putting on a lifejacket.
Tree Landing. So you could not make it to you normal landing zone and you are over a forest. Don't aim for that narrow road in the forest with tall trees because your wing tips will catch the branches, Collapse (Asymmetric, Recovery) your wing and you will fall to the road. Also, beware of power lines next to mountain roads. Instead, pick the biggest, softest looking tree, face the wind, cross you legs (to avoid cutting a vein) and close your arms, then flare to land right in the center of it, reducing your forward speed to zero. Keep braking until you can hold on to something. If this goes well you will end up suspended in the tree by your wing resting on the forest canopy, but you will not have a big fall to the ground. It will take time to untangle and maybe some repairs (at least an inspection), but you will have saved your bones from a fall. You can use your reserve as a "rope" to help you down. Look into your Emergency Kit. To get you wing out of the tree, detaching the lines from the risers can make it easier. Consider leaving the wing in the tree to return with climbing equipment and free the wing using boths hands while being secured to the tree. If the wing is caught in 2 trees, have a friend simultaneously free it from the other tree, just cutting down one tree could rip the wing. If your weight was partially or totally supended from your wing while in the tree, have the wing and lines inspected.
Fixed point method. Will you make it over that crest , river, power line or to the landing zone ? Look at the scenery ahead of you as if it was a painting. As you are flying into it (look at it for at least 15 seconds) pick a point ahead of you like a house or a tree on the crest you hope to pass. If that point is moving down (in your imaginary painting) then you will fly over it. Repeat this process until you identify a point that is neither going up nor down. That "fixed point" is where your glide will bring you. Try to average out any temporary sink or lift along the way.
Airplane on Collision Course. If an airplane is heading in your direction, do a high bank turn to show him you're there and head in the direction that gives the greatest chance of a miss. If you are close to a ridge, stay there.
Twisted Risers (Harness Flipped). Maybe because of a bad Wing Examination at Launch, you end up having both risers twisted in flight because your harness is rotated one full turn. Your wing is probably stable and stearable (although brake lines are rubbing on the risers). Go land (safest thing to do). The following is if you decide to untwist the risers in flight (only in stable air), and if you have either a front or shoulder-mounted reserve deployment handle, since side-mounted handles have a 50% chance of getting caught by a riser while rotating (see Reserve Handle Position). Visualise which way to rotate (pitch axis) the harness to untwist the risers. Fly to a place where there you have sufficient ground clearance. Let the wing fly at trim speed for a few seconds, let go of the brakes, and hope for no Collapse (Asymmetric, Execution). If a backwards flip is required, push on the risers while sending your feet (leg extended) upward and over the top, and for a forward flip, first get your legs extended and close to vertical before starting your rotation. Stretch out your arms so they will encounter the risers and stop the rotation after one turn, then grab your brakes.
Twisted Risers (Recovery). Your wing has spun around and left your risers twisted. This will also happen to pilots who reverse the wrong way during launch (only one twist turn). Your brakes are probably of no use at this time because they are caught up in the twist. If you need directional control, you can steer by reaching the brake lines (or D/C risers) above the twist. If the twist is not already coming undone by itself, grab the risers above the twist and un-twist yourself.
See also : Spin
Wake Turbulence - Another pilot just passed close upwind of you. If he is at the exact same altitude or above, there is no problem. If he is a little lower, you will feel the wake of his wing. The amplitude of the turbulence (wake) behind an aircraft increases with the load and how slow he is flying. The worst scenario is a tandem flying with lots of brake. This is one turbulence you can anticipate for.
Knot (Stable, Recovery). You have a knot in some of your lines (usually just after launch) but your wing remains stable. Maintain your direction by adding some brake to one side if necessary. Pull on the lines (if you can reach them) that lead to the knot, one at a time. If you can't undo the knot, go and land.
See also : Knot (Unstable, Recovery).
Signs of Growing Overhead Cloud.
Signs that the cloud you have glided under may be getting bigger : - A blue hole forms next to your cloud.
- The base of your cloud is getting darker.
- Your climb rate and the lift area (volumetric upward flow) is growing beyond expectations.
See also : Escaping Cloud Suck, Cloud Shape.
Cloud Suck (Theory). When a cloud's width reaches a certain size, air rushing from the side will not satisfy its air draw, and cloud suck occurs. So a cloud's horizontal size is the dominant factor, not height. Conditions that promote this effect : - Moist layer at cloud formation level, as the cloud will evaporate slower
- Low pressure system, or a heat low.
Detecting the condition : As you get near cloudbase, widen turn and if lift is widespread, expect this effect. See also : Escaping Cloud Suck, Cloud Shape.
Escaping Cloud Suck. You are at cloud base and still going up at 2+ m/s (400+ fpm). Before you lose visibility, use the Big Ears technique.If the air is rising at more than 8 m/s it is better to keep a constant heading to exit the lift, possibly combined with Big Ears (Execution) and using the Accelerator (Usage).
See also : Cloud Suck (Theory), Signs of Growing Overhead Cloud, Cloud Shape, Don't Fly into Clouds.
Airsickness.
Remedies, by order of effectiveness : - Eat Ginger :
- About 1 hour before you plan to fly, take 2 ginger pills (available from any drug store or health food place).
- Drink ginger ale all morning, all you can stand.
- Eat ginger biscuits in the morning.
- Acclimatization. Fly regularly and often.
- Elasticated sea bands worn on the wrist.
- Avoid watching the ground too much. Fly with a vario.
- Don't tilt your head up and down as you turn. Move eyes rather than head.
- Don't drink too much beer the night before.
- Get a good night's sleep the night before.
- Stay relaxed. Lower your shoulders.
- Eat a good, solid meal before flying.
- Urinate frequently prior to launch.
- Learn to stay in the thermal to get a smoother flight. See Centering the Thermal (using a Vario).
- Downgrade to a wing that dampens the turbulence. Other information:
Chewing gum does not help.
If you start to feel bad, land before you get too sick as your judgement becomes impaired with the progression of the nausea.
In-Flight Urination.
Options: - Use an adult diaper.
- Men : Use a condom-catheter.
- Men : Hang in the leg straps, lean far forward. Hold the brakes in one hand (behind you), use the other hand to urinate.
See also : In-Flight Drinking. Fixation - Instead of looking at the place we are afraid to crash into (this is called fixation), look where you want to go to. Some pilots end up in a field's only lonely tree for this reason.
Crash Landing & in Need of Assistance - You have made an emergency landing and you think you are hurt. Leave your wing unfolded as much as possible so people can find you easier and understand you are hurt. If you are alright, fold up your wing.
Snow/Sand in the wing. If you have scooped up snow/sand into your wing (while ground handling), it is likely to build up in the trailing edge during flight. This in turn, will weigh down the trailing edge, acting as additional braking input (your brakes will feel soft). With enough snow/sand (over 5 kg in a side of the wing) this can induce a Stall (Full, Recovery).
Loss of altitude causing pain in ears. This results from a higher pressure outside the ear in comparison to inner ear pressure (inside your head). Use the Valsalva manoeuvre to equalize pressure: Close your mouth, pinch your nose and blow gently. Avoid blowing too hard and over-inflating the middle ear space. Note that differential ear pressure automatically equalizes during altitude gain.
Hypoxia. Hypoxia originates from the lowering of air pressure with altitude, which lowers the partial pressure of oxygen, causing less oxygen to pass through the membrane of the lungs and therefore in the blood. Major factors which determine how one will beaffected by altitude induced Hypoxia : - Physical fitness is beneficial.
- Regular smokers and pilots having consumed alcohol or narcotics (experiencing a hangover) are disadvantaged.
The symptoms appear in this order : - Faster breathing and feeling tired. For pilots in bad condition, for a flight lasting a few hours, this can occur between 2000-3000 m (6500'-10000').
- Feeling of extreme well being.
- Delirious feeling. You will not be aware of this. Try to keep track of cognition by counting down.
- Loss of feeling in extremities. Cold temperatures will accelerate this beyond just the lack of oxygen.
- Loss of alertness, difficulty in making decisions. Side effects are nausea and headaches.
- Loss of consciousness.
- Death.
When these symptoms hit, you should get low fast. A flight over 12000' (3660 m) requires oxygen if more than 30 min, and 15000' (4570 m) requires constant oxygen flow if you want to keep your normal brain function. Using oxygen will :
- Warm you up quickly. The way our body produces heat is to oxidize our food/fuel we ingest.
- Improve your vision : Everything looks washed out and dull when hypoxic, and the contrast returns with oxygen.
Grunt breathing (forcing air in your lungs and pressuring it) can buy you some seconds of clear thought when you need it the most, but is not suitable for extended flights without oxygen.
Flying in Rain.
You are caught flying in the rain. The following is dependent on the intensity of the rain and your exposure time. - The fabric may stick together during recovery from a Collapse (Asymmetric, Recovery) or Frontal Collapse (Recovery).
- When flying in the rain your sink rate may increase because of disturbances to the laminar air flow over the wing.
- The soaking of the fabric (throught microcuts in the coating) increases the weight of the wing which causes the trailing edge to "drop", adding unwanted braking and increasing the angle of attack. This may lead to an irreversible Deep/Parachutal Stall (Recovery).
- Note that a wet wing will Stall (Full, Recovery) at a higher speed.
- do not perform manoeuvres that require strong braking like Wing-Over (Execution) or Spiral Dive (Execution),
- only do a "B" Line Stall (Execution) if absolutly necessary, and be light on the brakes during your landing approach.
- Do not do Big Ears (Problems).
- Make sure you maintain visibility for the rest of your flight.
- You may get cold.
See also : Landing near/in Rain, Line Length Change, Wing Degradation due to Humidity.
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