On Tuesday, July 14, 2015 at 10:40:51 AM UTC-5, Tango Eight wrote:
On Tuesday, July 14, 2015 at 1:37:39 AM UTC-4, Bob Kuykendall wrote:
On Monday, July 13, 2015 at 8:19:25 PM UTC-7, Jim Lewis wrote:
If Reynolds Number is the ratio of inertial forces to viscous forces where does aircraft weight come in?

What was the inertia part again?

Inertia of the *fluid*.

Re hasn't anything to do with the mass of the glider.

Evan Ludeman / T8

Yep. Rho Vee Elle over Mu. Fluid Density times velocity times chord divided by viscosity. But as the glider gets heavier, it flies faster at the same lift coefficient, so Vee gets bigger.

And, Jim. I am not seeing the "Performance Enhancement Through Airfoil Shape Correction" series in the Johnson Flight Tests section of the SSA Website. Might have to search an issue at a time from about 1977 through 1981. Dick got his Ventus in 1981, so the PIK went away then.

Steve