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What should I do when rope breaks at 220-360 ft [75-120m] when there is not sufficient runway to land ahead and not sufficient altitude to make a return manuover and land with the wind direction?

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    $\begingroup$ Do your best not to injure yourself, there is no one answer for this. Basically comes down to choosing a landing spot that gives you the best chance of survival. You've only got a few seconds to decide, make it quick. $\endgroup$ – Ron Beyer Jun 19 '17 at 14:09
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    $\begingroup$ 75m are enough to make a 180° turn and land at the airfield in opposite direction. So push the stick to gain enough air speed, pull the yellow knob to release the remaining rope, turn 180° and do a rear wind landing. $\endgroup$ – Timothy Truckle Jun 19 '17 at 14:41
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    $\begingroup$ What type of terrain is past the end of the runway? Where I flew gliders, there were paddocks ahead that were suitable to land on in an emergency. $\endgroup$ – Greg Hewgill Jun 19 '17 at 20:18
  • $\begingroup$ 200ft should be sufficient for a return. We practiced aerotow rope breaks at about 200' and returned with room to spare. $\endgroup$ – acpilot Jun 20 '17 at 4:07
  • $\begingroup$ Had it happen once, even lower. glider had next to no forward air speed and crashed into the ground. Luckily nobody got hurt, and the damage to the aircraft was minor. $\endgroup$ – jwenting Jun 20 '17 at 6:02
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Depends on the wind and the surrounding area. If there is enough headwind, you will be surprised how short your approach will be in a proper sideslip. Practise sideslipping at altitude, so you know what to do in an emergency! Otherwise, look around for an open field where to land; gliders are easily disassembled and carried back to the airport.

When the cable breaks, push the stick forward. Be prepared for dirt flying up and into your eyes if you push hard enough! Then stabilise at the minimum sink speed, release the remaining cable and look around for your options. There should be some:

  • Land straight away if headwind plus sideslip allow for a steep descent.
  • Fly straight a bit, then turn around 180° and land opposite to your direction at take-off. Do this only when there is no or almost no wind! 100m of altitude is plenty enough for this trick.
  • Keep flying straight and land on an open field near the airport.
  • Fly a triangular, shortened pattern and land in the regular direction.

If the airport is surrounded by forest or houses on all sides, try to land on the glider port - normally, the altitude bands required for the landing straight on, the 180° return landing and a landing from a proper pattern overlap enough so that there is never an altitude that would not allow to land on the airfield.

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  • $\begingroup$ Minimum sink speed is too close to stall speed! I would recommend at least 15 kn over stall speed in modern glass glider (in our club we fly approach with 55 kn on ASK 21). $\endgroup$ – Sławosz Aug 3 '17 at 16:07
  • $\begingroup$ @Sławosz: I agree, with a high aspect ratio wing the minimum sink speed can only be flown if the c$_{L_{max}}$ of the airfoil allows it. But gliders are designed to spend quite some time at that speed, and speed stability is great at low speed. Once you have a couple hours thermalling behind you, minimum sink speed is safe to fly. $\endgroup$ – Peter Kämpf Aug 3 '17 at 16:40
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    $\begingroup$ Kampf: I would never recommend flying minimum sink speed during emergency, when you are close to the ground. Even if you are good with thermaling, workload so low is so high, that you might easily stall. And since you probably want to do step bank turn, your minimum sink speed becomes stall speed (think 35-45 degree bank). Any misuse of controls can provoke spin, and during windy conditions you might easily stall because of gust and wind shear. I recommend this page: members.gliding.co.uk/bga-safety-management/safe-winching $\endgroup$ – Sławosz Aug 3 '17 at 19:15
  • $\begingroup$ @Sławosz: The minimum sink speed goes up with the load factor. Yes, you need to speed up for a turn. But you thermal with a load factor >1 as well. Again, after a few hours of thermalling you should be proficient, and flying at minimum sink speed gives you much more time to react. This decreases work load. A lot! $\endgroup$ – Peter Kämpf Nov 13 '17 at 22:53
  • $\begingroup$ I would not compare thermalling and emergencies here. During thermalling you have much better feeling of glider, you know how it behaves, and besides, you have lot of space to perform recovery. Flying with minimum sinking speed during cable break emergency is dangerous and you should never ever do it and never recommend it to anyone, especially on internet. Low level stall/spin accident is one of most popular accidents that kills glider pilots. Cable break emergency requires training and automation (at least on small airfields), you should never launch without clear plan in mind. $\endgroup$ – Sławosz Nov 14 '17 at 12:18
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It depends very much on your field which is why (in the UK at least) you list Eventualities (usually cable breaks) as part of the CBSIFTCBE pre-flight checks.

Usually you have Low level - land ahead, higher level - part turn and cross field landing, higher again-turn and reciprocal landing and higher still-run a truncated circuit and land as normal.

My main field has crops or turf fields ahead depending on wind direction so I have a lot of scope for a forward landing, it is a wide field with two main strips and a short diagonal strip so a cross field landing is possible and it is a long field so a reciprocal landing is straightforward.

Your best bet is to ask advice on your specific field from the CFI.

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    $\begingroup$ Your post could really do with some formatting, I found it quite hard to read, otherwise it's a good answer. $\endgroup$ – Notts90 Jun 20 '17 at 10:01
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    $\begingroup$ Much better with some line breaks, thank you! $\endgroup$ – FreeMan Jun 20 '17 at 12:22
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when there is not sufficient runway to land ahead and not sufficient altitude to make a return manuover and land with the wind direction

If this is really case, I would not launch in such site. But since you have winch there I assume its fine - maybe its just your feeling?

~90m alt when cable was broken, with return option, with 10 m/s wind - downwind landing, and I ended up 25cm before a fence on the end of an airfield

10 m/s is a lot ( 20knts, 36 km/h), if you manage to do tailwind landing, it means you probably could land ahead as well...

Anyway, BGA has great sources about safe winch launch: https://members.gliding.co.uk/bga-safety-management/safe-winching/

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