from the "red arrows" HP:

>How is the coloured smoke made?
Strictly speaking, it is not smoke but vapour. If you look closely at the underside of thr Red Arrows' Hawk, you will see an extra fuel tank bolted on to the lower fuselage. This tank contains ordinary diesel fuel. At the back of the aircraft, immediately above the jet exhaust pipe, there are three tubes. The diesel is pumped out of these to produce the vapour. Many people ask if it is one for each colour. The simple answer is no. Due to the quantity of diesel and dye required, it is pumped out of all three at once to produce the fantastic trails that you see. When the diesel from these pipes meets the extremely high temperatures found in the jet exhaust (over 550 degrees Celcius), the diesel immediately vapourises creating an intense white cloud. With separate switches on his control column, the pilot can chose to add either red or blue dye to the diesel and produce the two other colours. If you stand close enough to a Red Arrows display, or the wind is in the right direction, you will be able to smell the vapourised diesel but the experts tell us that it is completely harmless to health and environmentally friendly. Certainly, there are no cases of anyone's health being affected by inhaling the fumes. The company that manufactures the dyes has a website, and more information can be found at:
www.rohmhaas.com/businesses/chemspecs/dyes.html,
or you can e-mail:
[email protected]
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i sent an email, but never got an answer.
maybe you have more luck.
mec




http://www.raf.mod.uk/reds/faqs.html#faq8