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by dzeanah 3958 days ago
If drones acted like birds and actively got the hell away from the big, loud, flying thing approaching them then I would agree with your assessment.

And it's not my position that this is anything other than a marginal increase in risk; my position is simply that the risks associated with drone strikes can be quite significant.

3 comments

You might know more as a pilot but I was under the impression that birds don't get out of the way of big loud flying things. I found a source about birds not getting out of the way for cars once the cars are beyond a certain speed, but I couldn't find anything for airplanes.

http://rspb.royalsocietypublishing.org/content/282/1801/2014...

> If drones acted like birds and actively got the hell away from the big, loud, flying thing approaching them then I would agree with your assessment.

As you yourself said you're flying ground relative speed of 130 MpH, there's no way in heck a bird can get out the way. They won't even see you until you're right on top of them approaching at that speed.

It is extremely wishful thinking to believe that bird strikes don't have more often because birds avoid them.

This is simply not true in my experience. I have personally seen birds perform significant aerial maneuvers to avoid collision with my aircraft, going very close to 130MPH. By the time I see the bird it is often in a very steep dive, the bird saw my plane long before I saw the bird.
Once, while flying a glider, I shared the top of a thermal at 5,000 ft. with hundreds of swallows, darting all around me. I guess they were there to feed on the insects carried up there by the thermal, while I was up there because I needed the altitude to get home. Admittedly, I was only flying at 55 mph., and not making much noise.

I have also had a model airplane pull up in front of me, and that scared the crap out of me for a second, until I realized it wasn't the real thing - though, on reflection, it might have done serious damage if it hit the canopy or the horizontal stabilizer.

I'm surprised, not that they do something to avoid airplanes, but that it makes the situation better. Maybe birds are better at this than animals on roads, who often make the situation worse with their actions?
I think birds might just be better adapted to making highspeed course corrections than deer, squirrels, etc. Plus, they have the advantage of another dimension (and gravity) to use for getting out of the way.

Consider also that if a deer is spooked and freezes on the highway, you hit it. If a bird is spooked and freezes in mid-air, it falls to the ground.

I totally agree. It seems birds are not dumb enough to do this: https://youtu.be/F4ml61jI5ow?t=207 (at 3:42)
SpacemanSpiff is correct. This happens all the time. Wishful thinking or not.

I've personally seen it with ducks (6,500' on my first cross-country solo), hawks, vultures (or buzzards - can't tell the difference), seagulls, and those swarms of birds that like to fly close to the ground around airports.

The birds that are a greater hazard to small piston-powered planes are those that curl up into a ball when they sense a predator as they can drop right into you.

Still, many things that are both significant and marginal are not worth making a big deal out of.