Regarding whether it is a parachute flare or lens flare, Mick, I wonder if you could try a supplementary experiment? Use a thermal imager in black-hot mode to capture a descending flare at an appropriate distance (where the spot size is similar to the one in PR38). See if the color of the parachute matches what is seen in PR38 (assuming it is a flare), or if a similar lens flare effect occurs (assuming it is a flare). Additionally, I am very curious to know if the smoke trail of a flare in black-hot mode appears light-colored as it does in PR38 (though this might be influenced by the ambient temperature at the time)