For anyone who finds their F28 will not airstart and the butterly on the last valve will not open and allow the air to flow - take one dumb airport manager - place hin on a set of refuellers stairs - open the hatch at the bottom of the turbine housing and have him place his nice warm paw around the valve housing. The body heat causes the casing to expand an release the vale allowing airflow and scaring the living suitcase out of the person hanging on to the turbine as it leaps to life. A cold weather tip for those still working with the wonderful ladies.
EWL.