FLIES ON THE CEILING

Allow me for a moment to explore one of the great mysteries of aviation with a subject that has been around ever since Immelman rolled his Fokker rightway up at the top of a loop over the shell-holed killing fields of World War 1.

- GUY LEITCH

THE IMMELMAN turn may have fooled the Sopwith Camel flyer who thought he just about had the Hun in his sights. But was it really new?

Perhaps some insects have unknowingly being doing Immelman's for millions of years. And not only have they been doing advanced aerobatics, but they have been doing it with no brain to speak of and wings that appear to be ignorant of the requirements of Bernoulli.

The insect that is so well known for its consummate flying skills that even its name reflects this, is the fly.

After a few too many drinks fighter pilots have been known to end up flat on their backs looking up at the ceiling. And there they beheld flies running around, having happily landed - upside down.

How this feat was achieved has engaged the minds of many a fighter ace. Do flies land on ceilings after a half loop? Or do they simply roll inverted? And if they roll inverted, then is it off a straight roll or a barrel roll? The aerodynamic implications are profound.

Can a fly fly inverted?

For example, if a fly can land on the ceiling off a straight roll, does it need to, and can it fly inverted? The obvious place to start was with the aerobatic uber-pilots.

Scully Levin reckoned that, to answer the question, you have to first understand that flies are not born aviators and as such have no regard for balance and co-ordination. So in reality they fly along in a completely random and staccato fashion. Scully says that when they want to land on a ceiling they simply fling themselves upside down in a kind of barrel roll and then quickly clutch onto the surface before they fall off.

Dennis Spence is a firm believer in the straight roll.