Well thats interesting. However, the cooling effect of airflow in flight MIGHT keep the intake cool enough to allow ice formation in the right humidity, temp. conditions. . Why it should happen in clear air though is a mystery.

There were several unexplained flameouts last year at Winter jets, again in clear air. I dont have any more suggestions !

After the Ansett colla[se theres a surplus of engineers here !
BRG, David Gladwin