#### geosnooker2000

##### Well-Known Member

Design Cruising Speed (Vc) = 33 * Sqrt (wing loading)

Design Dive Speed (Vd) = 1.4 * Vc

Never Exceed Speed (Vne) = 0.9 * Vd

Then it says to flight test to expand the envelope further.

So am I correct in assuming that to increase Vne, that you MUST test to find a Vd, and then multiply that by .9 to establish a new Vne?

Example: FAR calcs yield for a hypothetical -

@2200 max TOw

Vc = 32' span’* 4.5’ chord = 144 sf (wing loading = 15.28) Sqrt = 3.9

Vc = 33* 3.9

Vc = 129 knots (148mph)

Vd = 1.4* 129

Vd = 180.8 (208 mph)

Vne = 0.9 *180.8

Vne = 163 (187mph)

If one wanted to increase the Vc to 170mph, one MUST put the plane in a dive to 238mph during a flight test? I mean, I realize the E-AB world theoretically has no "must", but ... best practices?