Understanding the Lift and Drag Curves

A deep understanding of the lift and drag curves means a pilot can apply that knowledge to better, and safer, flying. The graphic or link below are for my document Understanding the Lift and drag Curves. Understanding each portion of the curves very well and correlating that information to specific decision making and/or actions is the goal.

Lift and Drag Curves

Understanding the Lift and Drag Curves

Maneuvering Speed (Va)

My experience has shown me that many pilot’s (including instructors) understanding of maneuvering speed is incomplete, at best.  The latest version of the Pilot’s Handbook of Aeronautical Knowledge (PHAK), chapter 4 (UPRT) has an improved description of Va, but it still does not cover the subject completely. With a fuller understanding of Va, that knowledge can be applied to some emergency maneuvering which will increase safety.

A key point to remember is that you can only move one control, in one direction in smooth air for Va to be sure to work. Think about unusual attitude recoveries. What I have seen with 99% of pilots I have flown with, is on a nose low recovery they execute a rolling pull (i.e. using 2 flight controls simultaneously). That means a hard and/or abrupt rolling pull could overstress the aircraft as you can only count on the G capability of the aircraft to be 2/3rds of its rated G in a rolling pull. This means your Normal category airplane rated for 3.8 Gs is good for approximately 2.5 Gs in a rolling pull. The best way to recover from a nose low unusual attitude is to roll to wings level first (and reduce power to idle), then pull to fix the dive. This is more efficient and allows you to safely utilize the full G capability of the airplane, if necessary.

  • See my page on Emergency Maneuvering for more on proper unusual attitude recoveries.
  • Boldmethod has a really nice article on Va. HIghly recommended reading.
  • Flying Magazine also has an article (2005) on Va.


Check out this video on stalls

A great way to really improve aerodynamics knowledge is with practical application, such as by learning to fly a tailwheel airplane and/or Upset Prevention and Recovery Training (UPRT). Specialized Aero Works can help with both. Either way, a good course on either subject will teach you a lot about the practical application of several aerodynamic and physics concepts beyond everyday flight training, making for safer and more competent pilots.