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Comment by tswartz | Hacker News Reader

I think it's good that the FAA is documenting close calls with drones, however the press is a little overblown. This long time pilot views drones less of threat then geese or other large birds. That may change if drones get bigger and heavier, but all things point to drones getting smaller.

A pilot's view on drones: https://jethead.wordpress.com/2015/08/08/airliners-vs-drones...

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That's the view of an airliner captain. There are lots of us out there flying planes whose gross weight is well under 3,000 lbs, with a windshield that's made of plastic one eighth of an inch thick.

You're not necessarily wrong - I suppose it depends on how you define "overblown." Personally I have no desire to fly into a 12 lb drone at 130 miles per hour when the only thing protecting me is a thin piece of plastic. Or to have my prop destroy said drone while spinning at 2,400 RPM (which will require an engine tear-down, or possibly a 5-figure engine replacement). Or have one hit my horizontal stabilizer.

All of these may lead to a crash, which can lead to 1-4 deaths. Which may be inconsequential in the grand scheme of things, but it feels significant to me.

The point made by the airline captain, that birds outnumber drones by a vast number, applies no matter what aircraft you fly, though. Unless you're certain that your canopy will survive a birdstrike fine, it seems that the marginal risk increase is minimal.

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.

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.

My biggest question is what is a 'close call'? Is it something that a layperson would also agree is a close call? Some of the examples in the article don't sound too scary.

"Whizzed underneath aircraft as it approached a runway" leaves a lot of room for interpretation. Other examples in the article do sound more scary, but is that just cherry picking or typical?

Technically, the FAA defines a "near mid air collision" as an incident where there was a possibility of collisions with a proximity of less then 500 feet.

Keep in mind that's an airbus A380 is approx. 240 ft. long, 260 ft. wide and 80 ft. tall.

In that context, 500 ft. is actually quite close.

Though in the context of drones being limited to 400 feet of altitude, the whole flight could be considered a near miss with the ground...

The way some people fly, it is.

I don't see signs of drones getting smaller. It seems to me they will only get bigger and heavier especially if companies like Amazon are going to be using them to deliver products.

I'm an anecdata point for the "my drones are getting smaller" side here: My first couple of quadcopters were 10 and 12 inch prop sized, weighing in around 2 or 3 pounds - all me recent ones are _much_ smaller - 6 and 5 inch props with my "light" one being just under 200g (under half a pound) and the other three in the 1 to 1.5 pound range (depending on battery size and how much gear it's got on board - gps/video adds extra weight)

Tiny drones are much more common now as well - I've got a drawer full of Cheerson CX10s which weigh all of 30g or so (about an ounce). I strongly suspect the bulk of the "700,000 drones sold" are made up of devices closer to my CX10s than they are to "washing machine sized" ones capable of getting to 10,000 feet.

In reality they will most likely go down both paths. Amazon and others looking to ship goods via drones will want something bigger, while sports enthusiasts will wants something smaller.

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