Posted by: Alex | January 10, 2011

Golf Sierra Lima: Lessons Learned

[With minor edits, this is an article I wrote for New Zealand’s Soaring NZ gliding magazine, published in the December 2010 / January 2011 issue.  I’ve added a link to the GPS record of the flight in IGC format at the end of the article.  You can read my first person account of the flight here.]

I’ve repeatedly defended the safety of gliding to my non-pilot friends, and I also believed that I was a safe and conservative pilot.  I fit none of the characteristics of a stereotypical risk-taker.  Highly analytical, trained as an engineer, I’m a strong believer in planning and procedure as ways to reduce risk.  I regularly read two different aviation safety publications, and most would describe me as thoughtful, careful, and certainly mindful of minimizing risk.

There’s nothing extraordinary about these characteristics.  With very few exceptions most people I’ve met in the sport fit this description, and there’s no doubt that we all highly value our own life.  Yet, if all of the above is true, how did I end up crash landing a Discus in an unforgiving valley?  Is our sport ultimately more dangerous that we publicly state — and perhaps more sinisterly — actually believe it to be?

With two broken feet, I won’t regain my prior walking fitness for at least another six months and will be on crutches for half of that time.  I can expect early onset of arthritis in my right ankle by the time I reach my mid-40s.  While I am very fortunate that my injuries were not more severe and that I didn’t pay the price of this lesson with my life, the entire episode was preventable and a direct result of my own decision-making.

I’ve analyzed the accident in my mind countless times, and I believe there were three primary factors that influenced the ultimate outcome.

  1. I was in a competition. I’m nothing if not highly competitive, and this was the first competition I’d flown in, but I don’t believe this was the primary factor in the accident.  However, I was flying with a smaller altitude margin of safety than I would on a non-competitive cross-country flight.  In this situation it is even more critical to know precisely what your actions will be if you don’t find lift where you expect it.  With less altitude in reserve, there is much less time to react and safely get to a reliable landing area.
  2. I wasn’t 100% confident of my precise location. This, in combination with the next factor, was decisive.  With approximately 80 hours of flying out of Omarama, I was familiar with the region, but I’d never been in the Ahuriri valley at ridgetop height.  Cotters Hut was the next turnpoint, and I was happy to cross a few hundred feet over a ridge because I believed I would be entering the Dingle Burn valley — with its known landing strips — and not, as it turned out, Timaru Creek.  Had I known that I would be flying into a valley with no landable areas, I would either have increased my altitude margin of safety or chosen to cross at a different point.
  3. I was following another competitor, effectively outsourcing my decision-making to a non-consensual third-party. This was a fundamental mistake.  I wasn’t communicating with him, but seeing another glider crossing the ridge within 50ft of my own altitude gave me a false sense of security, particularly since the other pilot has far greater mountain flying experience than I do.  There’s a single word that describes this situation: complacency.  Although following and learning by example is a very natural behavior, trusting your own safety in the assumption that someone else isn’t risking their own is a dangerous mistake.
    The stakes are high when flying an aircraft, and you must take extra precautions against this behavior as the risks involved are often deceptive.  My situation is summed up neatly by Prof. Martin Hellman’s description of a 99.9% safe maneuver (see “Complacency: What Me Worry?”, June/July 2010, SoaringNZ).  In subsequent discussions with the other pilot, he was extremely concerned about crossing the head of Timaru Creek valley.  As a result, he was mentally prepared to manage and plan for the 0.1% or 1% risk involved and intended to make the crossing as quickly as possible.  I, on the other hand, was ignorant of the risk the other pilot was taking — however small — and as a result was completely unprepared for the heavy sink I found on the other side.

I still believe that gliding can be a very safe sport, but I’ve learned the hard way that the mountains can be a dangerous, unforgiving place.  For the glider pilot, this means adopting decision-making that is mountain-specific and takes these specialized risks into account.  If the majority of your experience has been in a very different environment, such as the flatlands of the UK in my case, you need to be particularly careful.  You may be a perfectly safe and competent pilot, but are you mountain-safe?

In crisp contrast to the rigidly procedural conduct of scheduled commercial flights that make them the safest possible form of transportation, glider pilots are under a much greater burden to be continually evaluating changing conditions and making safe decisions.  An accurate perception of risk is critical.  I have a few recommendations to make, and I encourage you to discuss this subject further within your own club.

  1. Always get a briefing. If you plan on flying into a new area, need a reminder, or will be entering the area in an unfamiliar weather pattern, it’s up to you to take 5 minutes to get a briefing from someone with greater experience.  An excellent rule of thumb is that if the cost of not doing something greatly outweighs the cost of doing that thing, you should always do it.  This is one of those cases.
  2. Clubs should specifically highlight unlandable areas on charts. It would be helpful for new, visiting or foreign pilots to see all unlandable areas visually represented on local charts.  A red border or light cross-hatch would serve as a keen reminder, particularly in the mountains where it is easy to quickly become trapped, even at relatively high altitude.  Seen altogether, it might initially be quite surprising how many of these areas exist that we regularly fly over.
  3. There is no substitute for training. I’ve read seemingly countless accident reports, but not once has one of these accident reports come to mind while flying.  In an emergency situation there is no time to think, and in my case, all of my decisions came back down to basic training and actions I had practiced countless times in the air.  I would encourage clubs to incorporate mountain-specific drills into their training programs.  For example, setting up a glider in a 1,000ft/min descent and asking the student to land the aircraft would emphasize how little time there is to react if caught in heavy sink.  I can imagine various exercises that could be set up in a motor glider on a calm day in the mountains to illustrate marginal or unsafe situations on a soaring day.  Compared to passively reading an accident report and nodding in complacent agreement, these types of drills drive home the message to the student and become an active part of their decision-making process.
  4. Update your glider’s safety kit. One unexpected factor in my landing is that no one knew whether I was alive.  My radio wasn’t able to transmit and because of my injuries I was limited in my signaling options.  Other glider pilots weren’t able to descend low enough to see me sitting on the wing of the glider without ending up in the valley themselves.  A set of flares (red, green, white) would have been extremely useful.  A signaling mirror would be another useful addition.  Leave these items in your glider’s first aid kit next time you go flying.

[You can download a GPS record of the flight in IGC format here.]


  1. […] Golf Sierra Lima: lessons learned –  Latitude 44 reflects on a gliding accident. […]

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