For an insight into what load alleviation does and how it operates you will find a good primer here
http://www.freepatentsonline.com/4796192.html
The load alleviation, along with new metal alloys, is credited with saving some 8 tonnes of weight in the wing structure of the A380.
Used
first on a civil heavy jet transport...Lockheed TriStar, of course (-500 model)....long ago.
Lockheed...far ahead of everyone else.