Birds versus Aircraft
 

Ok, this one is pure curiosity. I went flying today for what turned out to be a rather pleasant nav-ex with a student. On our way home near a ridge, a hawk or kestrel came very close to our aeroplane, darted across the nose, and swooped up behind us and then proceeded to chase us. Now I know a Cessna 152 isnt very intimidating, but can anyone explain why these birds are attracted to aircraft? It seems to happen quite regularly.

I have heard from pilots of microlights and gliders, stories of how such hunter-birds formated on them, and often circled around them and appeared to 'play' with the aircraft.

Perhaps they are curious? Perhaps they are attracted by reflections off aircraft surfaces? Will having landing lights and strobes on prevent them from getting too close (seagulls and other birds seem to get out of the way of these lights ok).

Your thoughts would be much appreciated. Any bird experts out there (the feathery kind)?

Kermie :)

Kermit,
From the far dark recesses of the junk closet that is my memory. Years ago I read somewhere that birds of prey are very territorial. I think it was an article concerning a glider club where a bird was actually attacking aircraft. Seems that the bird involved thought that the gliders were trying to muscle in on his territory. The close passes and circling are part of a display to scare the intruder off. Powered aircraft usually move faster and beetle off so the bird takes this as a victory on his part and goes back to what it was doing. Gliders on the other hand move slower and circle so stronger action is taken. Fabric wings can suffer quite badly at the claws of our feathered friends, less of a problem with tin and plastic kites but still quite a shock to all concerned when one thumps into you at a rate of knots. Don't know if lights etc will keep them off. I know that the bird-scarers on the ground have to change tactics periodically as they get used to the various methods employed.
Regards
WM. :)

Double barrel Purdy + Eley Kynoch No5 will sort it!! :D

It's never arisen in my limited powered flying career to date, but many years ago I used to glide off Sutton Bank (a prominent ridge soaring site in the UK) and we often shared the airspace with birds. I have read reports of gliders being assaulted, but they've always seemed to be happy to share the space when I've been around. Perhaps there, soaring in a relatively narrow bad of lift at a popular gliding side of several decades' standing has acclimatised the local fauna. I also used to fly radio controlled model gliders at various slope sites, often with hawks in the same block, and one or two people had models attacked (but only if they made moves that the bird might reasonably have considered aggressive).

Cheers people, thats answered my query quite well indeed. I had never even considered the natural territorial aspect. And I suppose ridges are excellent places for these big birds because they can glide around looking for prey and other birds (or aircraft) infringing their 'airspace'.

Well at least I can sound like I know why they do ut when students ask me now. :D

Kermie