I pulled these images out of the pile...
Way back when Lockheed hooked up with NASA to do a wake-turbulence alleviation program.
We mounted 8 smoke generators supplied by Frank Sanders, who made them for aerobatic airplanes, underneath the Tristar wing..
4 per side.. one immediately on the side next to the landing gear cover, one at the inboard flap outboard edge; the outboard flap outer edge, and underneath the wing tip.
The test was to fly a T-37 into the smoke trail behind the Tristar in landing configuration.. everything down..
It was discovered the turbulence at 5 miles behind the L-1011 was sufficient to kick the Tweet out of the smoke path.
Then the "alleviation" was tried, which consisted of full cycles left and right on the control wheel in the Tristar.
This had an enormous effect on the wake strength.. the T-37 could in much closer.
Of course the manuver would be completely unacceptable in a commerical plane. But it did work.
I took these images.. note how the tip flow almost goes away with down aileron...
There's a NASA report on the test, I'm sure... author should be Joe Tymcyzm.. something odd like that..
Pilot in the Tristar was Fitz-Fulton, and Bill Dana in the Tweet.
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Model aviation tie-in: To see if the most inboard generator was -on fire-, I had a sheet of Chrome Monokote pasted to the inboard side of each wing engine. Not that we had any way putting out a fire....