Riding On Air: Ridge, Wave, & Convergence Lift
Author:  Rolf Hertenstein, Ph.D., Meteorology, Triple Diamond Glider Pilot
From Bob Wander's "Gliding Mentor" series
Paperback, 104 pages, many illustrations
Dimensions: 8.43 x 10.87 inches (214 x 276 mm), Released in 2011, 1st Edition

The latest addition to the Gliding Mentor series is Rolf Hertenstein's brand-new opus Riding on Air: Ridge, Wave, & Convergence Lift.

Overview by Bob Wander
We think the title says it all. As a long-time airplane pilot and gliding pilot who first learned to fly in mountainous country, I am amazed and delighted at all of the things that Rolf explains in this book that have been a mystery to me for many years.  Most soaring pilots have some appreciation of ridge, wave and convergence lift; I wish EVERY soaring pilot had the depth of knowledge and experience with these types of lift that Rolf has, and that he reveals in this book.  We would all be the safer for it!  Riding On Air contains what you need to improve your soaring performance in ridge, wave, and convergence lift.  Furthermore, you'll learn why these types of lift sometimes disappear, seemingly without warning to the under-prepared pilot; and that in turn can lead to close scrapes (at best), or to disaster (at worst). 

Another thing that surprised me about this book was how often convergence lift is present, even when far away from mountains or oceans or other large-scale geographic features. I now see convergence events in the atmosphere almost-daily frequency, because I have learned what the physics of these convergences are, and how to recognize them by visible signposts in the air.

Table of Contents
The Gliding Mentor Series, 2
Author’s Notes, 3
Author’s Introduction, 4
Chapter 1: Ridge Lift, 8
Ridge Lift Basics, 8
Complex Terrain, 14
Other Considerations, 22
Techniques, 24
Cross-Country Flight Using Ridge Lift, 29
Other Hazards, 30
Footnotes for Chapter One, 35

Chapter 2: Mountain Wave, 36 
Wave Basics – How Waves Form In The Atmosphere, 37
Mountain Waves: The Two-Dimensional Conceptual Model, 39
Other Wave Forms, 48
Complex Terrain, 52
Rotor And Other Hazards, 59
Forecasting Mountain Waves, 65
Using Wave Lift, 70
Cross-Country Soaring Flight Using Wave Lift, 79
Footnotes for Chapter Two, 80

Chapter 3: Convergence, 82 
What Is Convergence?, 82
Convergence Happens On Many Scales, 83
Examples Of Convergent Wind Fields, 84
Sources Of Convergence, 85
Finding And Using Convergence, 89
Footnotes for Chapter Three, 91

Chapter 4: Combinations & Miscellaneous Sources Of Lift, 92 
Thermals And Ridge Lift, 92
Thermals Under Wave, 93
Ridge And Wave Lift, 96
Diurnal Mountain Winds, 96
Other Lift Sources, 98
Footnotes for Chapter Four, 99

Appendix, 100 
Numerical Weather Prediction Models, 100 
Technical & Weather Websites, 102 
For Further Reading, 103 
The Soaring Society of America, 103
The Gliding Mentor Series, 104 
The Gliding...Made Easy! Series, 104