I am sure that at one time or another, eventually your chemtrail research will lead you to satellite images of the telltale plumes over coastal waters. Often they are described as "ship-tracks" in marine cloud research papers as well as by the "highly regarded" - sarcasm - debunking community. In most cases I would not argue that ocean transport ships would be capable of creating sulfur laden soot plumes, which draw moisture from the highly humid environment at ultra low altitude.
However, it would seem that researchers of the E-PEACE campaign wanted to juice things up a bit.

[Linked Image]

The experiment does mention the use of:

"(1) Controlled release and atmospheric distribution of three different size ranges of particles in flight (Albrecht) and on or (does this mean - in addition to?) by a dedicated ship (Russell)
(2) Large Eddy Simulations (LES, Seinfeld) and Aerosol-Cloud Parcel (ACP, Russell) modeling studies constrained by the observations to test our ability to quantitatively predict the dynamical response to increases in particle concentrations in the natural atmosphere
(3) Satellite analyses (Sorooshian) of marine stratocumulus to constrain the radiative properties of the natural, perturbed, and regional cloud systems"

E-PEACE campaign Scripps Inst.

The Bridge - w/ sat images of shiptracks

May not be the "hand in the cookie jar" moment for a chemtrail aircraft, but! Anyway, they were kind enough to provide photographic evidence that there are open air releases of "test chemicals" being conducted off of our coastal regions. In this instance, the photo is labeled on the right as product: Shell Diala AX, which is refined mineral oil normally used in electrical transformers.
I guess we should be glad that it isn't the old PCB oil they used to use in transformers! You would think that the dude in the picture would be wearing some type of filter mask (at least that is what the MSDS recomends) - just goes to show you what you can get for low budget geoengineer researchers at present.