Hot answers tagged

7

The Boeing 737 predates the use of supercritical airfoils at Boeing (which again predate the work of Whitcomb, but I digress). In order to keep changes to a minimum, the 737 wing airfoils only got the equivalent of a "nose job" over the years to bring their drag divergence Mach number up. Note that regional airliners fly a bit slower than ...


5

Answer to the implicit question: Yes, the more recent airliner airfoils are indeed secret. Look for reports like this to see what is out there. Answer to question 1: Try the linked NASA Technical Paper 2969. Answer to question 2: Your viscosity is for sea level. Try to use the value for the tropopause and it will be only ⅓ as large.


2

See what the L/D curve for NACA 0012 is at 15 degrees AoA, and calculate the Reynolds number for that chord and airspeed. That estimates the maximum lift, i.e., force at right angles to the duct. Then you know, by leverage, the max force exerted by the servo on the vane, and from the servo arm's length, the max servo torque. But that estimate of lift will ...


Only top voted, non community-wiki answers of a minimum length are eligible