Wing Ballast Distribution

On Dec 10, 9:23*am, n7ly wrote:
On Dec 10, 8:31*am, jcarlyle wrote:
Weight in the wing is load relieving. Try it with a paper airplane.
Tape coins around.



When you water ballast the four wing tanks of an LS8a you fill the
inner tanks first, and when you dump the water there’s provision for
the inner tanks to drain last. With a RS LS8-18 (and the newer DG LS8-
s) this procedure is reversed - the outer tanks are filled first and
there’s provision for the outer tanks to drain last. This was a
deliberate decision, because mechanical changes were made to the two-
handled dump system levers.

Why would aircraft desgigners want to keep weight towards the wing
tips? Does it have something to do with going from a 15m to an 18m
span? Wouldn’t the increased moment of inertia and wing spar bending
negatively affect performance?

-John- Hide quoted text -

- Show quoted text -

The weight toward the tips provides an interial resistance to roll.
That means the ride is a little smoother as the wing has greater
resistance to differential vertical gusting across the wingspan. It
is the same principle that tightrope walkers use by carrying a long
heavy pole.