A news helicopter was struck by a suspected drone, causing substantial damage | Hacker News Reader

A news helicopter was struck by a suspected drone, causing substantial damage

cnn.com

46 pointsprostoalex56 comments

As a drone owner I think it’s only a matter of time until enough stupid and reckless things like this happen before it’s ruined for everyone who is safe and thoughtful about their drone use. DJI has gotten better as has the FAA in making it easier to decipher where you can and can’t fly, but the fact of the matter is that they have a lot more they should be doing. Why not limit flights in the US to the FAA mandated 400ft ceiling? There are enough high altitude videos on YouTube to indicate that people still like to test the limits and don’t think of the possible consequences.

While I'd understand if such a limit was implemented, for me it'd kill the hobby. Not because I like going high above the terrain -- that's illegal, after all -- but because I do my photography somewhere very hilly, with grades averaging 45 degrees in most of the places I fly.

"120 meters above the launch site" would also mean "120 meters away from the launch site", and then only in two possible directions. The other two have cliffs.

Before you ask, it's pretty deserted. It's also really pretty.

I don’t like restrictions as well. I am quite capable of working within the law without mandated restrictions. It seems weird as well since from about 8yrs old I would go to my local hobby shop myself and buy model rockets capable of reaching several thousand feet easily.

At least some states require notification of local authorities before launching model rockets (such as California). Some states also put out altitude ceiling regulations for them. When I lived outside Chicago in the first half of the 00's, you had to get approval for launching above 2500 ft. You were also required to cease launching if any low flying aircraft were visible. You could get in some real nasty trouble if you violated those rules.

You could phrase it as distance from nearest terrain rather than altitude.

That's how it's already phrased in the law, but it isn't a practical rule for DJI to implement. Maps aren't detailed enough, so they'd have to put ground radar in the drones, which wouldn't work...

Or they'd just reduce the max altitude above launch site limitation already in their firmware. An easier-to-implement limitation that stays within the legal restrictions.

> Maps aren't detailed enough,

Yes they are. All of the US is mapped to 3m horizontal resolution and 1m vertical resolution, the world to 15m. This is grossly overkill. A 30m lossless compression dataset will run you about 1GB, which is plenty for this purpose.

It's free too.

https://terra.nasa.gov/news/aster-digital-elevation-model-ve...

I think we'll see more flight restrictions on drones, and enhanced structural requirements for resisting drone strikes for low-speed, low-altitude aircraft such as helicopters.

Eventually all aircraft are low altitude.

There are valid use cases to fly over 400’. I believe the FAA even allows this with the correct permit/license/whatever. The drones have this capability so it can be used in the correct circumstances. The problem is people disabling that existing 400’ limited mode without FAA approval.

Would mandating ADS-B on drones provide enough warning to other aircraft?

>The problem is people disabling that existing 400’ limited mode without FAA approval.

>Would mandating ADS-B on drones provide enough warning to other aircraft?

I assume the same type of person might just disable the beacon..

No. Most aircraft don’t have ads-b receivers and TCAS doesn’t use it.

I’m not sure what the percentage is, but at least some aircraft will have to have ADS-B Out in 2020, per https://www.faa.gov/nextgen/programs/adsb/faq/#g2

I like the idea of requiring ADS-B Out on drones. For those aircraft with ADS-B In, it introduces the possibility of seeing drones sending ADS-B Out. And others with ADS-B receivers will be able to see and identify them.

As an additional step, drones could be required to use ADS-B in for aircraft avoidance.

Well there’s a button on the drone to disable the altitude restrictions, I’m not sure why you’d disable the ADS-B transceiver unless you are just trying to cause trouble.

It's intriguing, even as a drone owner myself, how the general attitude seems to be "what? no way, couldn't have been a drone". When you look at the damage, it certainly wasn't a bird.

The general attitude also seems to be "there was something unidentified up there, it must have been a drone".

What else is small, isn't a bird, and flies? It certainly wasn't a birthday balloon.

Baby Superman?

To be accurate:

"A news helicopter was struck by a UFO..."

While technically accurate the general public associates UFOs with aliens

To be fair, it seems rather unlikely an hobbyist drone would do that particular damage to the tail considering both objects velocities. The article mentions "a pop", "a bang", "a light". Uh, a flare maybe?

Where does the article say their velocities, and how does a flare get up to 1,100 feet?

Wouldn't you get smearing of blood and other remains with a bird?

I've never heard of a drone proper (vertical lift, multiple motor R/C) operating at 1100', which is well above the legal limit. Without proof, they're both speculating by not presenting factual news, and scapegoating drones. That's why the NTSB doesn't jump to conclusions before the facts are in.

PS: Here's another, better article with the news station involved and video interview:

https://abc7.com/federal-agencies-investigating-drone-collis...

Do drones really move fast enough to puncture a helicopter? If that's what happened, should they not have found at least some of the drone inside the helicopter afterward?

Well the heli was moving too. Plus, the damaga is not that crazy looking. Totally believable

The damage is on the side of the tail. How fast can a helicopter move sideways?

Not as fast as they move forwards, but still pretty quickly[1]. I think 50mph is doable.

[1]: https://www.youtube.com/watch?v=WGp2okWpyJg

it can rotate, and thus sweep the tailaround, quite fast

It looks like it's the leading edge of the horizontal stabilizer, but it's not totally clear from the photo. A leading edge impact is definitely indicative of a forward flight collision.

Edit: Much better photo: https://cdn.abcotvs.com/dip/images/5734793_120419-kabc-11pm-...

Yes it's the h-stab. Upper surface of leading edge corresponds with a nose-down pitch of the helo in forward flight.

Tail rotors on helicopters move fast enough such that anything that touches it can puncture it.

Is that what was punctured?

The article says that it was the tail of the helicopter that was punctured; they don't say anything about a rotor. I was assuming by "tail" they mean the narrowest (fixed) part of the body toward the rear, not one of the rotating blades. The article includes a picture of the damage, but that's not clearing up the ambiguity to me -- it's not tapered like a tail, and it's too fat to be a rotor.

Looks like it hit and punctured the horizontal stabilizer rather than the tail rotor. Since this is a front-facing part of the helicopter it is quite feasible that the helicopter was moving faster than the drone, adding to the energy of collision.

There is a secondary vertical rotor on the tail, for yaw.

I would think the object touched a rotor blade and got converted into shrapnel.

I find it hard that a drone could puncture and dent a 3mm thick sheet of metal. Racing drones can move up to 100 km/h or so, but good luck hitting the moving tail of a helicopter at that speed.

Racing drone owners are generally very responsible, in my experience, and don't fly that far/high anyway. Photography drones don't go anywhere near that fast, and have altitude limits.

Photography drones have regulatory altitude limits. Nothing stopping somebody from flying higher than that other than the threat of a fine if caught. It's the relative speed of the two objects colliding that matters, not just the speed of the drone.

> Nothing stopping somebody from flying higher than that other than the threat of a fine if caught

And the built-in software limit that physically prevents the drone from flying higher.

And what ubiquitous built in software would that be?

You're aware there are myriad non DJI options for drone photography platforms yea?

"Software limit." On Hacker News. Used unironically. These are truly the end days.

Luckily that hasn't stopped people who know nothing about a subject from opining.

The closest example that comes to mind was done by the University of Dayton

https://giphy.com/gifs/48LkLrgh9AKmcFUVxe/html5

That simulated an aircraft's wing vs a drone at 238 mph. I was actually kinda surprised by the amount of damage inflicted.

If only the skin was damaged, what effect would that have on the ability to land a typical passenger jet?

Also, did that simulation mostly damage just the skin, or did it also get the machinery inside the wing?

Machinery inside. They simulated a bird strike too and found that to damage the internals less, so they suggested that future drone development might take that in to account and crumple closer to a bird strike.

Ever seen a bird strike? And a drone is heavier than most birds.

Helicopters regularly cruise at over 120 mph, and the skin is around 1.27 mm thin. The stuff gets SHREDDED in a crash [1], it's generally not load bearing and acts as an aerodynamic fairing for the rest of the helo. The tail boom contains a truss space frame to do the literal heavy lifting. You see those "NO STEP" marks on commercial jet wings, because a human walking on some spots can cause damage. It's very plausible that a 5 lb rigid object (which is also how much a brick weighs), could do significant damage when striking skin at 100+ mph.

Add.: A better photo shows it's the leading edge of the horizontal stabilizer that was damaged: https://cdn.abcotvs.com/dip/images/5734793_120419-kabc-11pm-... The puncture location on the upper surface of leading edge corresponds with a nose-down pitch of the helo in forward flight.

[1] This is something I notice wrong in CGI aircraft crashes, where it breaks into big solid chunks that bounce. In reality, aircraft crumple, disintegrate, and smear into tiny pieces on impact, leaving a long trail of small debris.

> [1] This is something I notice wrong in CGI aircraft crashes, where it breaks into big solid chunks that bounce. In reality, aircraft crumple, disintegrate, and smear into tiny pieces on impact, leaving a long trail of small debris.

I recently came across a very good example of this, barely anything left. Scroll for photos: https://avherald.com/h?article=495997e2

On a semi-related note... News helicopters: why? How are they justified at this point?

It's crazy to me that we're flying entire people on fragile, noisy, polluting machines over dense urban areas so the 7 people still watching TV can look at... traffic?

I think this should go away entirely or be done with (drum roll) drones.

Cost will very likely move in the direction of drones and not human-powered helicopters. Or, looking at another way, once Police departments are flying drones everywhere, and if that footage were accessible to citizens, then news orgs would for sure stop paying for the current system. That's a big "if", though. It just as easily might be the drones come, but the footage is locked up behind legal departments.

Thank god for them: https://youtu.be/Em8C6AvD4sk

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