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Comment by Animats | Hacker News Reader

Look at the picture. Something punched a sizable hole in the nose. That plane hit something much harder than a bird.

Nonsense. At 300-500mph, hardness doesn't really matter, mass is the killer. There's no reason to suspect from the damage alone that it was a drone.

https://duckduckgo.com/?q=jet+bird+strike&t=brave&iar=images...

The plane was on landing approach, during which it isn't traveling 300-500mph.

Also, notice how in every single one of the pictures in your link there are blood streaks. This is pretty much universal in a bird strike, as a strike hard enough to damage aircraft skin is also hard enough to severely injure any bird, leaving at least some feathers behind. The photo in the OP doesn't have either blood or feathers. That doesn't totally rule out a bird strike, but it does make it less likely.

For anyone else. The landing speed of a 747 is around 166mph-172mph [1].

[1] http://lmgtfy.com/?q=747+landing+speed

Approach speed is anywhere between landing speed and cruising speed. They don't slow to 170mph before descending or entering a landing approach, for example.

They have to be at or below 250 knots below 10,000 ft unless they're in a special control zone.

Here's a bird strike with no blood or feathers: https://www.upi.com/Top_News/US/2016/04/28/Bird-strike-leave...

High or moderate speed would even blow the blood, like spraying windshield fluid on car at 70 MPH

If they flew through rain it might wash the blood away.

Feathers may not be seen on damaged surfaces, relative wind speed on nose(after hit) would mostly blow the feathers away from surface, however feather may be found deep inside of broken places where wind could not take feathers on escape.

Birds can cause the same damage. Here are just two examples, the second creating a much bigger hole than the supposed drone strike:

https://www.aviationcv.com/aviation-blog/2016/bird-strike-de...

EDIT: Here's one with a "drone" still hanging from the nose cone: https://www.miamiherald.com/news/local/community/miami-dade/...

There is some previous of a bird hitting a 737 on the nose and doing a lot of damage [1]. As well as the speed factor mentioned by sibling comments, the nose cone is typically made of thinner and lighter material to avoid blocking, well, RADAR.

1: https://www.telegraph.co.uk/news/aviation/12192721/Bird-stri...

> That plane hit something much harder than a bird.

Something like a drone? That's what the article says. It's even what the headline says.

Must have been a big ass drone. That's a huge hole.

That said, the headline is speculation. All we know is that the pilots heard a loud bang and there is a hole in the nose. It might be a drone or it might be something else.

> Must have been a big ass drone. That's a huge hole.

Small things at (relative) high velocity make big holes. It's physics.

This is theoretically the entry hole though, it typically does not get larger with velocity.

When you see bullet impacts on a target the entry hole is typically bullet size while the exit hole can be much larger.

I'm not saying I'd expect the perfect outline of a drone like on a cartoon, but the hole should be roughly the size of whatever hit it unless something subsequently exploded inside or collapsed the support structure and allowed the airflow to further damage the skin.

It does, but to a point (as you pointed out), but no commercial plane is going to hit a bird as fast as a bullet impacting a target. Aircraft skin is relatively thin and easy to tear, and may fragment leaving a much larger hole than the object that hit it.[0][1][2]

0. https://www.telegraph.co.uk/travel/news/Bird-strike-rips-blo...

1. https://www.nydailynews.com/news/national/bird-bash-leaves-g...

2. https://www.dailymail.co.uk/travel/travel_news/article-34900...

Speed can cause outsized damage. Meteor Crater in Arizona (1200 meters in diameter) was caused by a relatively small meteorite (50 meters across).

No need to get aggressive. The article also says that we don't actually know yet what hit the plane; OP was simply saying they agree that a drone strike is plausible.

Three months ago, a military jet fighter Saab JAS 39 Gripen crashed here in Sweden after a mid air collision with a flock of large birds.

The Swedish military has five to ten of such incidents per year, through almost all ends with the pilot doing an successful emergency landing. The crash sparked discussion that a bird warning system should be in place in order to prevent accidents in the future.

Those crashes are often caused by engines ingesting birds.

Here's one that happened to a BAe Hawk in Moose Jaw, Saskatchewan a while back:

https://www.youtube.com/watch?v=GuLcVkW4YVg

The on-board video shows it crashing into a corn field not long after the crew ejects.

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