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Comment by MrBuddyCasino | Hacker News Reader

> While the unmanned aerial vehicles are small, drones can wreak incredible havoc. A collision with a wing, engine or any part of a larger aircraft can cause severe damage.

How so? Which part of a helicopter is so sensitive to the impact of a drone? They are not fast and they are not heavy.

> “A bird collision with a plane can cause a plane to go down,” said Jessica Gardetto, a spokesperson for the National Interagency Fire Center. “These are hard plastic items.”

Different scenario. Planes crash into birds with a huge speed, and they can get into the turbines, which obviously can damage them.

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This is seriously your argument? Alright, hold my red bull, it's math time.

Let's assume they're using a Boeing Vertol 234, a civilian model of the Chinook commonly used for firefighting. They're double rotor, and as such the rotors are slower than most single rotor helicopters, at around 225 RPM [1] at full throttle.

The rotors on a chinook are 60ft in diameter [2]. This means that the edge of the blade is traveling about 188.5 ft per revolution. At 225 RPM, that's 706.8 feet per second, or ~481 miles per hour, on par with a commercial aircraft at cruising speed.

So yeah, smacking a drone into a relatively thin and lightweight rotor blade at over 400 miles an hour may cause a wee bit of damage.

[1] http://www.chinook-helicopter.com/standards/areas/blade.html [2] https://en.wikipedia.org/wiki/Boeing_CH-47_Chinook#Specifica...

Just to be clear, I think the people flying drones are assholes. I'm not saying "don't make a such a big deal out of it". I'm just wondering what the actual danger is. Are the blades really that sensitive? I'd assume they would easily shred a drone to pieces and not be harmed in the process, because they already need to be quite tough to not tear apart under the centrifugal force during normal operation. But I have no idea, thats just my intuition.

The issue is a drone, or debris from a drone, getting sucked into the engine intake. This debris can effectively turn the engine into a large amount of shrapnel, crippling the aircraft and its mission.

https://en.wikipedia.org/wiki/Foreign_object_damage

First good reply, no hand-waving, with real proof, thanks. Theres an actual picture of the possible damage a small bolt can cause on a helicopter turbine.

> Which part of a helicopter is so sensitive to the impact of a drone?

Wow. Everything except the skids, if those are present. Foreign object damage to a turbine and fracture of a blade are the ones most likely to be catastrophic.

The very fast spinning blades, the engine intake, the windshield, the tail rotor. Pretty much the entire vehicle is composed only of critical parts, because any extra parts add weight and increase fuel costs. Helicopters, and especially their engines/blades, operate at high speeds as well.

The blades?

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