24 November 2015

Catch the Dive!

Old lessons, new manoeuvres, assessing wings and skills... I was delighted when Toby Colombé at Passion Paragliding said he had space for me on his wing control course in Oludinez in October. As ever it was great to learn in a group and Toby’s special talents, helped by the impressive Mike Agnew eased us all along.
I am indebted to Sigmund Aamodt for allowing me to use some photos and footage from the course. Sigmund is a fast developing Norwegian pilot on a high EN B glider who flies cross country whenever he can and entered his first competition this year.
Sigmund showed impressive skills in the early part of the course but was keen to push harder into dynamic manoeuvres to fine tune his timing and learn just how aggressive control inputs sometimes need to be. The core exercise for this bit of the training is to do rapid exits from spiral dives. During the exit the pilot needs to manage pitch and roll in a high energy situation. Rather like what can be experienced with a big collapse and recovery in strong XC conditions.

The picture shows a dramatic consequence of mistiming inputs!
Sigmund working the Rush 4
Sigmund's video gives us a chance to explore further. 
0:00 to 0:10 - A nice hard spiral to build up the energy.
0:11 - An intentional quick exit from the spiral by going hands-up. As opposed to bleeding off the speed over several revolutions this allows the glider to come out of the spiral quickly and climb with lots of energy.
0:14 - The glider is now well behind Sigmund and not quite level to the horizon. His weight is towards the high side of the glider and he might be pushing himself over with the opposite risers to try and even things up.
0:15 - The glider is now starting to come back overhead, but with an "oblique attack." Lots of brake is being applied.
0:16 - The glider is still shooting but Sigmund has let his hands up.
0:17 - Oops!
So how could the glider be managed better through the stages?
  • A cleaner exit can be achieved by a brief application and release of opposite brake at 0:11 - the "piff-paff." On some glider/harness combinations the spiral will continue without opposite brake input.
  • After a dramatic exit it is likely that the glider or pilot will still have some rotation so it probably won't be nice and level with the horizon. This is the opportunity to briefly use one brake to steer the the glider back into a level position  - the "compensation." The ideal time would be at 0:14. At this stage the pilot should be sat back symmetrically in the harness, looking up and back at the glider. This helps in two ways: it loads the glider evenly; the pilot can judge the size and duration of the compensation input. Get this right and the recovery dive will start symmetrically instead of obliquely as at at 0:15. At this point the hands should be right up to the pulleys. Braking now introduces camber and removes reflex and can actually make the dive worse.
  • Once the glider is accelerating hard past the vertical at 0:16 it is time to brake the dive hard. The further past the vertical the glider has come before brake input, the deeper and faster the input will need to be. At 0:16 the hands should roughly at hip level or what ever is required to brake the aggressive dive.
  • Once the glider has stopped its forward shooting it is time for hands-up and the pilot will swing under the glider and fly away calmly! For more about pitch control have a look at Toby's article.
Many thanks to Sigmund for sharing - it certainly reinforces the value of training to develop your reactions. Sigmund is a positive and bold pilot and really went for that spiral. Most pilots will gradually build up through a wing control or SIV course to high-energy maneuvers and avoid such a drama. Kudos to Sigmund for pushing hard when he had a life jacket and Toby in the rescue boat. He didn't need him anyway.
When I met him, I suspected Sigmund to be made of stern stuff and when I learnt what his name means in Old Nordic: "Victory man from where the rivers meet," any doubt was removed!

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