High diurnal rates in the desert and mountain west create high winds and strong thermals most summer afternoons. Attempting to maintain altitude in strong thermals by pulling back in downdrafts and by reducing power or pushing forward in updrafts is extremely inefficient. We are leaned and usually at full throttle in low powered airplanes. Attempting to maintain altitude will not maintain altitude but will cause us to fly slow in downdrafts and fast in updrafts for a net loss in ground speed and altitude efficiency.

With practice, we can feel ourselves going up or down after the bump of hitting different air. In the meantime, we can use the tack to diagnose updraft or downdraft. The rpm will decrease when we are in a downdraft. We simply push over to fly fast through the downdraft. The VSI will peg down. There will usually be a bump at the bottom. If however, it just peters out, the VSI will wiggle on the peg indicating we are no longer in the downdraft. We level the airplane and watch the rpm for the next indication while waiting on the VSI to catch up. Conversely, the rpm will increase when we enter an updraft. We pitch up to fly slow in the updraft. The VSI will peg up. When we are no longer going up significantly, the VSI will wiggle on the peg.

Either by feel or instrument indication, we want to fly fast through downdrafts and slow through updrafts for a significant increase in ground speed and altitude efficiency.

If we are more than 3,000' AGL and under the hemispheric rule in the mountains, we are flying an airplane too powerful to appreciate the greater power and inexpensiveness of God's free natural energy.

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There is one potential problem with this method.

The method is quite correct, the right term is "Speed to Fly Theory" which was developed by Dr. Paul MacCready who was US National soaring champion at the time. MacCready was using this to maximize cross country speed in a sailplane, and involved the predicted or expected strength of the next thermal or series of thermals you were going to encounter. The "expected thermal strength" (respectfully called the "MacCready setting" to this day in sailplane competition) is not of any real use in a powered aircraft.

However, MacCready's concept of speeding up in sinking air and slowing down in rising air, is very relevant to making the most out of thermals no matter what you are flying.

The problem is, that rising air is very frequently right next to sinking air, and density altitude wreaks havoc with true airspeed. So you're bombing along in the mountains at max cruise, which is a lot higher than your ASI reading at altitude. You encounter sinking air, so you speed up to get through it quicker. Just as you get into your yellow arc, which means the plane is near redline in true airspeed, you kit that rising air right next to the sink.

You can easily be going as fast or faster than your Vne, and get hit with a hard edge gust. Now the really unsafe part:

Since you were in sinking air, your rate of descent while "diving through the sink" might be 2000 feet per minute down. If you fly ingot a 1000 feet per minute thermal, which is common where I come from, you just hit your wing structure with a net vertical gust of 3000 feet per minute. Near or perhaps at TAS redline and ASI yellow arc. That's in addition to the speed, which makes the jolt much sharper and instantaneous.

The sailplanes we flew in competition had long and flexible wings, which very very effectively absorbed these gusts like a pair of diving boards on each side of the plane. A strut braced or light metal cantilever aircraft could very easily be damaged or hurt someone.

My dad had me in gliders at a young age. Foam blocks on the rudder pedals of the Blanic. Best training for my business. Working on checking out a pilot at my Ranch but I expect too much from new pilots. I find out that I am paying for short field proficiency and Engine operation theory / management training. Im afraid I do not have the patience to also train a pilot how to find and use lift. Since we do not need to maintain heading I do explain the importance of getting out of sink.

Yes it is rough in the 2,000' ups and downs, but when your little airplane will not make the pass in cool, calm morning air, you have to find energy elsewhere. 500 fpm climb at sea level does not compare with the 2,000 fpm available from thermals and/or orographic, ridge, hydraulic lift. God is bigger than even many big engines. If you have to watch the airspeed indicator to know what is going on, you are way behind the relative wind noise, relative feeling of buoyancy, stick pressure and position (don't look down,) relative horizontal nose speed of movement for angle of bank in a turn, and dirt and other loose items coming by your face. The airplane will tell you how its doing long before the airspeed indicator will.