How are the coloured vapour trails made?
The vapour trails begin life as diesel fuel, contained in an extra fuel tank bolted on the underside of the Hawk fuselage. At the back of the aircraft, immediately above the jet exhaust pipe, there are three small tubes through which the pilot can pump small quantities of this diesel. When the diesel meets the extremely high temperatures found in the jet exhaust (over 500 degrees Celsius), the diesel immediately vaporises creating an intense white cloud. With separate switches on his control column, the pilot can add red or blue dye to the diesel and produce the other two colours. During a 30-minute sortie each aircraft can produce vapour for a maximum duration of 7 minutes. Depending on wind direction it is sometimes possible to smell these coloured vapour trails. All independent checks carried out since the Team first started using vapour trails in 1965 have indicated that there is no discernible hazard to health, that only microscopic particles of residue reach the ground and that t
