April 30, 2013

Flying the ASH-25 with Kempton Izuno



Getting the chance to fly dual cross country with an experienced pilot in a real XC machine like an ASH-25 is a rare opportunity, so when I got the call from Kempton Izuno asking if I was available to attempt a XC mission from Williams Soaring Center to Crater Lake, OR, the only answer possible was, “Yes!”.  The weather was predicted to be very good Friday thru Sunday in the Eastern Sierra, where I normally fly; Kempton was planning the flight in a slightly different air mass to the west over the coastal ranges in Northern California.  I could have made the 6 hour drive to Williams on Friday during the day, but I decided to take advantage of the great local soaring weather instead and made a 400km racing flight from California City.  It made the drive that evening tough, arriving at Williams at 11:30pm, but the bunk house was ready to go when I arrived and I was asleep before my head hit the pillow.

I woke up the next morning to the wonderful smell of pancakes, bacon, and coffee emanating from the bunkhouse kitchen.  I got dressed and found Kempton; we discussed the plan for the day and weather forecast  over breakfast.

The forecast had been drying out all week leading up to the flight, decreasing the probability of making the jump from the coastal range to the Cascades, taking Crater Lake out of possible turn points.  However the weather would still support a nice flight up the Mendocino Mountain Range and give me a chance to pick up tips on techniques and tactics from Kempton.

The following is a summary of the key points I picked up from Kempton’s flying that others may find useful.  A little background, Kempton is not a racing pilot; he is a very experienced and exceptional distance pilot and has developed his techniques and tactics over more than 30 years of starting early, coming home late, and flying for distance.

1)      Kempton makes small and aggressive corrections when centering thermals.  When asked which thermal centering technique he uses, i.e. Decrease Bank as Lift Increases, he responded by saying he doesn't have a well-defined mechanical technique, he relies on feeling the lift and making the necessary corrections.

2)      Kempton emphasized staying to the high ground; if you fall off the upper ridge get to the next lower ridge as fast as possible.  What was interesting to me was how much this rule dictated the path we took, we made fairly large off heading deviations to follow all the little ridges, spines, and plateaus.  This allowed us to press further along our course earlier in the day.  Kempton mentioned that these techniques were taught CNVV at St. Auban, France.

3)      When we were >300’ over a ridge Kempton took a path that favored the upwind side of the ridge over the sun side.  It seemed to work and allowed for good protection from getting low on the lee side.

4)      Kempton was always reminding me to look up.  The Cu were small, wispy, and cycling quick; often we were in a thermal climbing in good lift only to find a Cu forming slightly to one side of our climb, a little adjustment and we found a better climb. Kempton developed these techniques throughout the years and were confirmed through conversations with Brian Spreckley and Peter Alexander.

5)      On our way home, Kempton discussed using the outlets of all the little valleys along the mountain range as potential sources for a late evening thermal.  Thermal triggers, caused by catabatic winds creating a mini convergence ‘finger’ extending into the flatlands from the outlet of mountain valleys can often be the key to getting home. A note from Kempton: This technique was picked up from Stefan Leutenegger, a top Swiss pilot.  Stefan said this is a common occurrence in the Swiss Alps.
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Here are Kempton’s thought on our flight:
In regards to finding a 7 knot thermal east of the peak at Yolla Bolla, “I found it puzzling why the cu was over the bowl, not the peak. The winds had been basically zero, so I concluded that with nothing to push the thermals one way or the other up the sides of a bowl, they would pop from inside the bowl. “
T15 (peak) had lift right over it, but after that, and in the low ridge area north of T15 to Hayfork Peak and Buckhorn, the shreds were not over the peaks, but rather on the sun side slope about half to one mile away from the peaks.  We saw a shred east of Hayfork peak so went for that and climbed up to 9k, then saw another shred at Buckhorn (S of the peak) and went for that. By this time it was 3:10p, and it was time to turn around. On the return leg the lift was in about, but not exactly, the same spot, supporting the light wind random trigger source theory.

Overall the experience was fantastic.  Kempton and I had lots of great discussions regarding in-flight decisions and he was willing to try out my theories by deviating from the path he would have taken.  We supported each other while the other was flying by calling out cu’s in the distance, timing cu cycle time, looking up, tracking other gliders, calling altitudes, etc.

I would also really like to thank Rex and Noelle Mayes, and the rest of the crew at William Soaring for some of the best hospitality in Soaring.  The atmosphere is amplified by a top notch group of local pilots and amazing accommodations.