>> Home >> Coaching >>

---

---

Article sourced from google group originally writen by Simon (Safety Officer) Aberdeen Handgliding and Paragliding Club with comment at bottom from Dave Thomson (Head Coach PG) - LLSC:-

---

There has been a lot of comments about flights in strong winds recently (especially at Formal) and the committee members think we should put out some practical thoughts.

Some of the more experienced pilots in the club have had some interesting experiences in strong wind conditions. From my memory bank:

• Myself, Leadlich, strong wave and rotor, pushed into the gully to North of the ridge multiple collapses
  
• Myself - nasty conditions and rotor having to land in the Glenshee valley in a southerly increased by the tight valley.
  
• Matt and Adrian, pinned on front of Leadlich in rough air and took some time (20 mins) to get out front and able to land, barely going forward at the landing field due to the wave.
  
• Ian Downie, flew Leadlich in strong wind conditions, had to use speed bar to punch out whilst low, took a big collapse while low and hit the ground - broken pelvis, ankle and wrist, long recovery.
  
• Paolo - flew Pressendye, wind escalated, had to turn and run, land on the downwind part of the hill about 1 km behind the ridge
  
• Several pilots in the Killarney open in 2005 - got pushed behind a spineback in strong conditions, several cascades and tree landings witnessed by myself and Matt
  
• A bunch of us on Fichell last year, gagging for the first early spring flight, nearly took off and wind went from nothing to 30 mph plus in about 6 or 7 mins
  
• A southern club pilot I know who got blown from the ridge at Famara to the permieter of Lanzarote airport before he could get down.
  
• Matt landed 1 field away form a cliff edge on the North Coast, more or less going backward on bar (OK he'd flown from Pressendye or Morrone but was definitely running out of land).
  

Hope I am not labouring the point, but strong wind conditions can be dangerous - margins get reduced and the situation you are in can change quickly - you need good situational awareness and may need to make some rapid deicsions!

Therefore if considering strong wind flying I suggest:-

• Check the forecast wind speeds at several heights - e.g. Weatheronline shows speed at ground level, 950 hPa level and 900 hPa level (about 3000 ft). Be aware if there is a dramatic increase in wind with height. My personal rule of thumb is if the wind is 20 knot at 3000 ft forget any flying in the high hills. 10-15 knot is a better window to aim for and 15 kt / 3000 ft forecast conditions aren't always flyable for PGs.
  
• Check how the weather forecast will change - is the wind expected to be constant or is it increasing through the day. If its increasing, how long will the possibly flyable window be?
  
• When you get to the hill, go to the top and check the wind speed at the top of the ridge. Take a wind meter and don't be embarrassed to use it. Asess how gusty it is.
  
• Be honest about your launch capability. My personal rule of thumb is 18 mph when I am current.
  
• Assess the conditions for a while - say 15 mins at least to see if wave is affecting the site (especially Leadlich).
  
• In Scotland its my experience that wind at sheltered sites may be Ok but once you poke your nose above the topography (about 4000 ft in the big hills) there are no mountain barriers to stop the wind - often there is an increase at this height This seems more prevalent at the end of a cycle of high pressure weather (wind typically form S, SE, E) . This is especially true at Craiglich where we've had many days where HG have launched and flown wave to the N Coast, but its been too funky for PGs. For this reason beware of low sites where you can go downwind into high mountains in these conditions e.g Runvey crag near Spittal of Glenshee.
  
• Look for a benign high wind launch area with no downwind obstacles and space to dump the canopy if the launch goes wrong.
  
• You can consider launching further down the slope out of the compression BUT ONLY if you have made a full assessment at the top of the ridge first, and preferably have good experience of the site on which to make a judgement.
  
• Make sure your speed bar is fitted and you are competent at using it actively - i.e. putting it on/off according to the glider feedback, not just holding it locked on at one position. If the bar is on, don't apply your brakes until the bar is released. (Use a little pressure on D risers instead). In windy or turbulent conditions I fly my speed bar continuosly adjusting the pressure - same as active flying on the brakes.
  
• While flying, do plenty of penetration checks. Point into wind and assess your forward motion over the ground. Try it with a little bar on to see the difference, and feel the conditions. Notice how quickly you and other gliders go downwind when you turn. On a ridge do S-turns before full 360s if concerned about the downwind groundspeed. If you have an integrated vari-GPS, keep a check on the into wind groundspeed.
  
• If you are in the air and it is getting too windy, the safe thing is to find an area free of topography and obstacles to land in.
  
• Option 1 is applying some bar and pushing out to the front of the hill and out of the lift band, then out to a nice large flat field. Build up the amount of bar slowly, feeling the conditions. Putting higher amounts of bar on is OK if you are high enough to recover from a BIG tuck if it goes wong. Hint - if its getting windy, push out sooner rather than later - the lift band will be further out form the hill, you can stay up further out form the hill and it will be easier to escape if it gets worse.
  
• If you are not high enough to recover from a big tuck, use a little speed bar to stay in the lift band and gain more height. Then either push out more agressively to get away from the hill, or turn and run downwind to find a safe landing spot.
  
• If you are high enough and less confident about bar, or have a low performance glider, consider going downwind straight away - especially if the downwind terrain is free of obstacles.
  
• If you are not confident handling speed bar and recovering from big tucks, you shouldn't fly in windy conditions. (You can build up this skill bey practicing in more benign conditions).
  
• Some sites are more benign for leaving the ridge low and running downwind - e.g. a nice round flat topped mountain like Pressendye.
  
• If you do have to run downwind, move to the most benign part of the hill before you do - i.e the roundest flattest bit.
  
• The decision of when to run downwind versus push out front is a safety one (i.e. not a "where the car is" decision) - go with your assessment of the safest option depending on the terrain, the wind conditions, your glider and your capability.
  
• On landing approach, aim for the upwind side of the field. If its turbulent and windy low down you will want to come off the speed bar so you don't want to be aiming for the downwind edge and have to use bar all the way. Monitor the wind speed and penetration carefully - often the wind reduces low down and you may suddenly find you will over-run the upwind side of the field. If this happens, come off the bar and change your ground track to change your approach. If its windy all the way to the landing field, then when coming in to land, reduce the bar smoothly and if possible come off the bar. Better to land going slightly backwards than take a big collapse low down with no room to recover. Fly the glider actively all the way to the ground. Be ready to PLF.
  
• For an XC out landing in windy conditions, lose height over the upwind end of the field and then make a J approach. Preferably have another field or 2 downwind that you can also run to if its really windy.
  
• If in doubt - don't fly. Watching others in marginal conditions (and talking to them about it afterwards) can be a great way of learning.
  
  Stay safe everyone.
  
  Regards
  
  Simon (Safety Officer)
  
  

  ---

  
  I would consider 20 knots (37 kph ) at any height as indicating not flyable conditions, in any terrain. Even at base, a windspeed higher than the trim speed of the glider is not my idea of fun.
  
  Strong wind at base can seem tolerable, but sooner or later you'll come down and often without a lot choice where. That's where wind and mountains becomes an issue. I've had a few experiences I don't want to repeat, on the lee side of Munroes. Maybe I'm just wuss, but I wouldn't plan to fly big hills with 3000' forecast wind of more than 12 knot (22 kph).
  
  Turbulence is roughly proportional to the square of windspeed so the last few kph make a big difference.
  
  Stability of the airmass is equally important - An inversion at around 3000 can cause seriously unpleasant conditions in our big hills with lighter winds.
  
  David