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What Happens When a Drone Hits an Airplane Wing? [video]

102 points by protomyth 8y ago

ars 8y ago
It made a hole and caused internal damage. But would not have taken down the plane. Recommendation to make drones "frangible", so they break on impact and do not penetrate into the wing. In comparison a bird crushed the wing surface but did not cause internal damage.
- fermienrico 8y ago
  Wings also hold fuel, so it can catch on fire.
  - lolc 8y ago
    We're looking at a collision between a big kerosene-tank and a fist-sized Li-Po battery.
    - jtbayly 8y ago
      Sounds like a fun time.
    - karlkatzke 8y ago
      Yeah... the fuel in many GA aircraft is usually inside of a relatively thin rubber bladder inside the wing. It does not self seal. If it leaks, it’s going to run down the back of the aircraft and may drain into the cabin. In some aircraft with engines mounted on the rear of the aircraft it can run towards or into the engine. Now, on top of dealing with an emergency that has disabled control surfaces like ailerons and flaps that pass through the inside of the wing, damaged the leading edge which is critical for generating lift, and potentially having a wing come off if you hit a rough patch of air with a damaged spar, the pilot may have to deal with a fuel leak that would endanger the people in the cabin or cause a midair fire. Not good.
    - sokoloff 8y ago
      Most piston aircraft run on gasoline, which is far more flammable than Jet-A/kerosene.
  - deleted 8y ago
    [deleted]
- splurge100 8y ago
  Now also imagine the drone hit the windscreen, and not the wing. Or went into the prop / engine. Or hit the tail and damaged the rudder. The leading edge of the wing is likely the best case scenario. All others probably result in far more serious consequences.
- AmVess 8y ago
  The drone penetrated the wing and broke spars. It is very easy for such an impact to also destroy control surface cabling, wiring, or hydraulics which certainly can cause a plane crash.
  - JasonFruit 8y ago
    Dented the front spar and some compression members. It probably reduced the wing's margin for maneuvering, but should still have been manageable to get down safely. Not to downplay the danger, but let's not exaggerate it either.
    - murukesh_s 8y ago
      What if the drone was heavier or impacted somewhere else more critical? Drone is pretty much a mini aircraft so it has to be regulated somehow.. which i believe is being done already!
    - AmVess 8y ago
      I am not exaggerating. Several years ago, a bird strike in Alaska resulted in a fatal crash of a 172. Does it happen often? Probably not, but a large heavy drone can easily take down a small civilian aircraft.
      - JasonFruit 8y ago
        I'm just pointing out your exaggeration of the result of this test, not the danger in real life, which I believe you assess accurately.
- CPLX 8y ago
  That was enough to take down a plane easily. Wings don't just sit there on the ground like in the video, they support the fuselage of the plane against serious aerodynamic forces. They are under load, it's like taking out a bunch of columns at the ground floor of a building. Not to mention that wings are full of fuel, as well as the cables or hydraulic lines connected to the control surfaces.
  - jetrink 8y ago
    The engineer that conducted the test concluded that the plane would have been able to survive the impact. However, he said that if the test were conducted on a faster aircraft like a business jet, the results could be worse.
    - geoelectric 8y ago
      Realizing I should go watch the video, did he say at what height it would be recoverable? For example, there's been at least one high-profile plane crash in the past (Lauda Flight 004) where a thrust reverser (diverts the jet output forward instead of backwards, used to slow you down quick during landing) deployed mid-flight. That should have been recoverable, but turns out Boeing only projected outcome at low speeds and altitudes. The outcome at cruising speeds/altitudes turned out to be far different and the plane went down. While cruise wouldn't be an issue (don't think they get up that high!) I'd expect the outcome of a drone hitting a flight control surface might vary between takeoff, landing, and lowish-altitude holding.
  - bronco21016 8y ago
    You’d be shocked how little of the wing is actually supporting the entire structure. Typically there is one main spar that holds up the entire wing and the skin and ribs only hold a fraction of the load which is distributed to the spar. As you might imagine the spar is going to be a pretty heavy duty piece of aluminum and not easily damaged by something like this. A wing can sustain a fairly large hole as long as the spar isn’t damaged. Control cables would be a concern but hydraulics and fuel aren’t typically going to be a concern. Fuel isn’t as combustible as everyone likes to think. There are also additional tanks. Hydraulics offer redundancy on aircraft that use hydraulic control surfaces. I’ve seen a Cirrus SR20 hit a deer at takeoff speed and leave a 2.5 ft hole in the skin of the wing the went as deep as the reinforced fuel tank. The aircraft continued flight and came back around and landed just fine. Even flew to the repair airport after cleaning up some loose fiberglass. Personally what worries me more is what would happen if they fired this thing at the plexiglass windscreen. In a GA airplane that would likely be fatal.
jessaustin 8y ago
This type of incident seems unlikely to happen by accident.
- SteveNuts 8y ago
  Against a commercial airliner you'd pretty much have to be flying right near the runway of the airport, but for a GA Cessna those can be flying pretty much anywhere. I can easily see how a small plane could accidentally hit a drone.
  - xstephen95x 8y ago
    yeah and on 9/11 they had to fly right near the twin towers.
    - pavel_lishin 8y ago
      That's a good point - you don't even have to kill anyone to effect a pretty significant scare. How much would it cost to buy enough drones to shut down an airport by having them hover in front of the runways? And how quickly could they be taken down?
      - kungtotte 8y ago
        Unless the drones have onboard AI, all you'd need is to jam the signal. It can't be that hard to shut down drone frequencies seeing as how they have gear to shut down cell phones (to prevent them being used to set off IEDs).
        pavel_lishin 8y ago
        In my particular movie theater plot, I'm assuming they've been loaded with firmware to just keep station at a particular location in space. Plus, how long would it take to get signal jamming equipment to the runway? Can it be used safely around an airport? Etc, etc. Novel-research stuff.
JoblessWonder 8y ago
Interesting experiment. Looks like a lot of fun to use that air cannon to blast things at things. That aircraft doesn't have any de-icing equipment so it is basically just sheet metal where it hit. I'd be curious to see what would happen if it ran into a wing with than just a thin skin.
sbradford26 8y ago
The sheer amount of airplanes in the sky at anytime is incredible. Also designated no fly zones can change and users may be unaware. So to avoid this issue I think we need to do more than just depend on users knowing where they can fly and not. Drone collides with helicopter in a temporary flight restrictions (TFR) zone: https://arstechnica.com/tech-policy/2017/12/drone-collides-with-us-army-helicopter-puts-1-5-dent-in-rotor/ https://arstechnica.com/tech-policy/2017/12/drone-collides-w... Map of all airplanes currently flying: https://www.flightradar24.com/40.21,-88.24/6 https://www.flightradar24.com/40.21,-88.24/6
- inevitable2 8y ago
  The sheer volume of the sky at all times is even more incredible!
- rootusrootus 8y ago
  That's really an ADS-B map, which is not actually all planes flying, at least not yet. It's especially sparse for small private planes, which are probably the most likely to find themselves tangling with a drone.
  - sokoloff 8y ago
    Prediction: There will never be a time when all air traffic is ADS-B out equipped. It's certainly not a current mandate, and is only mandated for aircraft desiring access to some select airspace after Jan 1, 2020. I will equip, because I own a hangar inside the mode C veil of Boston, but if I were 6 miles farther out, I may very well choose to avoid class B/C airports and not equip. Lots and lots of traffic will certainly make that choice.
- prawn 8y ago
  There is a lot of air up there. I fly drones in Australia (https://serio.com.au/ https://serio.com.au/) and it's easy to stay well out of the way of large aircraft (don't launch anywhere near airports, and restrict your maximum altitude) and helicopters (you can hear them from a long way away). DJI's software enforces a survey with local regulations before you can fly. The default settings are all very restrictive too. The authority here provides an app that quickly indicates the flight rules in a particular location - airports and approach paths, non-controlled aerodromes, etc. It's quick enough that it's easy to check as part of your setup procedure. The riskier situations I think are cropdusters (fly very low and launch from rarely used airfields) or sightseeing planes/choppers (operating close to the ground despite launching from a fair distance away). I often fly at this location (https://serio.com.au/media/20180171.jpg https://serio.com.au/media/20180171.jpg) and on weekends there can be vintage sightseeing planes coming down the beach in that bay, definitely below the 120m (400') drone limit.
secabeen 8y ago
I don't know that much about air dynamics. How likely is it that a drone would strike exactly on the leading edge of a wing, as opposed to passing just over or just under the wing?
- gist 8y ago
  Also (along the lines of air dynamics) I am wondering about whether an airplane has a force in the direction it is traveling in and if that force does push anything small out of the way. As a small example if I have a pot in my hand and I move it in the direction of a tissue the tissue will move. So we have a very large airplane wing moving in the direction of a much smaller drone and the test does not simulate that at all.
  - deleted 8y ago
    [deleted]
  - dreamcompiler 8y ago
    Two things: 1. Airplane wings are designed not to "push" forward on the air in front of them. That's drag and airplanes are designed to minimize it. 2. What little air is pushed forward is only going to be affected by the oncoming wing a few inches in front of the wing, and at 230 mph closing speed that doesn't provide nearly enough time for the force of the oncoming air to move the drone out of the way.
    - gist 8y ago
      Thanks. But one question. What is the chance that a drone in the path of an airplane will not be impacted by the force of some other object on, or design of, the plane that is not the wing? For example the engine or the landing gear (small plane) or the fuselage? So we hover a drone in front of a small plane and will the small plane hit the drone? And if a larger jet will the drone remain in place or move out of the way by some force (not the wing). And remenber that the drone has to exactly strike in a particular way. As an example (of 'in a particular way') think of a nail on the road. The nail needs to be in exactly the right position to puncture a modern tire. That only happens in a very small amount of cases (or with a screw). Normally if it doesn't randomly happen the nail or screw gets pushed aside and does not puncture the tire. [1] This is not a statement based on expertise I am just offering another point to consider and am curious. [1] This I think is what happens with a paper cut sharp edge and precise angle.
pmilla1606 8y ago
I think 230mph is unrealistic for such tests. A quick google search shows something between 70mph - 100mph on approach [1]. I doubt drones are found at altitudes of aircraft at cruising speed. I'm not saying that this isn't a concern but can somebody with actual aviation knowledge (I have none) chime in and explain the 230mph figure? 1: http://www.mooneyland.com/how-to-land-a-mooney-properly/ http://www.mooneyland.com/how-to-land-a-mooney-properly/
- tlb 8y ago
  Landing speed for a loaded 737 can be up to 203 mph [0]. Among general aviation, a Gulfstream 450 landing speed can be up to 186 mph at full weight and high altitude. The drone itself can have some speed opposite to the airplane. 230 mph is only a little conservative. [0] http://www.b737.org.uk/vspeeds.htm http://www.b737.org.uk/vspeeds.htm Note that numbers are in knots. [1] http://www.code7700.com/g450_vref.htm http://www.code7700.com/g450_vref.htm
  - pmilla1606 8y ago
    But surely a 737 wing is completely different to the one tested here? I'd be very interested to see a 737 wing being tested like this.
    - falcolas 8y ago
      Completely different? No. Still mostly aluminum sheets riveted to spars with a big ol' gas tank in them. Biggest difference is the control cables would be mostly replaced with hydrolic lines.
    - deleted 8y ago
      [deleted]
  - bronco21016 8y ago
    Your referenced speeds for the 737 are for an overweight landing at the lowest allowable flap setting. 186 mph for the G450 would also occur at a weight above max landing weight. An incredibly low likelihood.
dsfyu404ed 8y ago
This is not all that much more than the damage done by a Canadian goose. I guess makes sense. The drone has to fly so it can't be built like a tank.
mrguyorama 8y ago
I wonder how easy it would be to make drones have a stronger radar signal? It's probably not nice to clutter up the displays of ATC, but it would be I think a more direct solution for controlled airspace
- GaryNumanVevo 8y ago
  It's fairly straight forward to implement this. Some modern USAF missiles are built to mimic various planes' radar signatures to suss out any ground-to-air missile defenses before actual planes move in. [0] [0] https://foxtrotalpha.jalopnik.com/the-pentagons-flying-decoy-super-weapon-is-about-to-get-1669729445 https://foxtrotalpha.jalopnik.com/the-pentagons-flying-decoy...
- philip1209 8y ago
  Radar reflectors are common on certain aircraft or even boats: https://www.gaelforcemarine.co.uk/en/GB/Trem-IOR-Radar-Reflector/m-3603.aspx?PartnerID=22&utm_source=google&utm_medium=shopping&utm_campaign=UnitedKingdom&gclid=EAIaIQobChMIw8Sn6fvq3QIVCpPtCh3ArgWNEAQYASABEgKoefD_BwE https://www.gaelforcemarine.co.uk/en/GB/Trem-IOR-Radar-Refle... They used to equip some stealth aircraft during training with them so they could be more easily tracked.
  - Scramblejams 8y ago
    Stealth aircraft deploy them whenever they’re operating in civilian airspace so they can integrate into the existing radar-based ATC infrastructure. They’re called Luneburg Lenses: https://en.m.wikipedia.org/wiki/Luneburg_lens https://en.m.wikipedia.org/wiki/Luneburg_lens
cde-v 8y ago
I'm honestly surprised we haven't seen anyone try to take down a plane by flying a drone into an engine on takeoff.
- neuralRiot 8y ago
  It turns out, the risk of terrorist attacks are much lower than some agencies want us to believe.
- stordoff 8y ago
  I was discussing this with someone a few weeks ago, and swarms of drones (flying in formation) are a concern, and the only thing really stopping it is that no one has tried (as neuralRiot says). Unfortunately, I don't really know how you would prevent it.
  - baddox 8y ago
    I’m sure it could be done, but I’m also willing to bet there are even easier ways to threaten airplanes that don’t involve relatively new consumer products.
ejo4041 8y ago
My brother actually hit a deer on takeoff a few years ago in Charlotte. It was all over the news that day. It did not do as much damage as this drone did. Mostly just dented in the face of the wing which caused fuel to leak out. It was a little closer to the fuselage. That prompted an emergency landing.
- berbec 8y ago
  Delta v for the deer was likely significantly lower. The video says impact increases with square of velocity.
- bufferoverflow 8y ago
  How does a deer hit the wing? Aren't they rather high? A small plane that's much slower on takeoff/landing than a commercial airliner?
- rasz 8y ago
  >It did not do as much damage as this drone did. probably wasn't shot out of air cannon at 230mph
zokier 8y ago
I guess it would depend on if it is this sort of drone: https://defensesystems.com/articles/2017/05/02/~/media/GIG/Defense%20Systems/22mq25aboardaunnavyaircraftcarrier%201.jpg https://defensesystems.com/articles/2017/05/02/~/media/GIG/D... or this sort https://api.ning.com/files/LxgTrYw8IckDE2ljSVm61iv7MVev4tELr4SQs5fDfPCCGgJEr8F6wV9IgLRaqzvX8Yr8UMSmcYPmgNHxSTWad*1y1neY7WEV/DSC_8004.JPG https://api.ning.com/files/LxgTrYw8IckDE2ljSVm61iv7MVev4tELr...
mothsonasloth 8y ago
A year ago I saw someone flying a drone from the top of the Shard building in London. The person was promptly told to land his drone immediately by the security. However the scary thing for me is that the smaller business planes and commercial plane that fly into London city go really close to the Shard on their approach. So definitely a collision is now a real risk
DominikPeters 8y ago
I enjoyed that the expert's recommendation was not "regulation", but to change drone design so they more easily break apart on impact. More likely to be implemented and does not need enforcement on the consumer level.
- mxuribe 8y ago
  Well, there go my plans to build an adamantium drone! :-p (I know, i know, adamantium is not real...)
  - StavrosK 8y ago
    Even if it were real, you'd get a ~3 minute flight time, so eeeeeh.
- cco 8y ago
  I would also support drone manufacturers self regulating via GPS deadzones in designated no fly areas. Nearly all drones of a meaningful size are GPS enabled and could be disabled in range of a no fly zone. Yes it could be spoofed, yes it would require some effort from manufactures, but self inflicted regulation as an industry here could pay dividends if the alternative is ham fisted regulation following a drone/airplane catastrophe.
  - NiekvdMaas 8y ago
    That's exactly what all major drones do. DJI has a market share of about 75% [1] and you cannot take off any of their success in a restricted flight zone. Flight zone updates are also mandatory and forced to the users. Same for Yuneec, which has another 5% market share. 1. http://thedronegirl.com/2018/09/18/dji-market-share/ http://thedronegirl.com/2018/09/18/dji-market-share/
    - cco 8y ago
      Ah interesting, I didn't know!
- 8y ago
airuser0 8y ago
It's similar to the question asked here before: "Can a dog kill a man with a cane?". I personally accepted the answer:"Depends on the dog, depends on the man, and depends on the cane".
- saalweachter 8y ago
  “How is the dog holding the cane?”
foxylad 8y ago
I'm concerned that the test uses a static wing. If you drop a fishing float directly in front of an obstacle in a river, it will be moved with the water around the obstacle, not hitting it. Air is a lot less dense than water, but my instinct is that unless the drone hit a very narrow sweet spot it would simply be swept around the wing. And even in that sweet spot, there will be a buffer of compressed air that would substantially slow the impact. Could someone with more knowledge of fluid dynamics comment on the applicability of static tests like this to actual aircraft damage?
- Splines 8y ago
  I do not have a fluid dynamics background, but my hunch is that at the speeds involved, and the fact that there is a column of air from the cannon already surrounding the projectile, that this makes this simulation close enough.
  - foxylad 8y ago
    Ah, good point about the air column.
- grogers 8y ago
  Does a baseball move out of the way of the swinging bat? There might be some small effect, but it's not the dominant one. In this scenario the wing is just a slightly bigger bat, and the drone is a slightly bigger ball. It would of course take a very (un)lucky strike to collide dead on like this, but not that unreasonable. I do hope they test indirect strikes too though.
  - jessriedel 8y ago
    I think you're probably right, but note that even for a powerful hitter, bat speed is ~80 mph. This is significantly less than 238 mph used in the video as a typical airplane speed.
- raquo 8y ago
  Air movement is a rounding error in this test. Suppose the curvature of the wing's airflow could in fact push the drone 15cm up or down in the time it takes the wing to advance 30cm forward (a tiny fraction of a second). That would require such a high G load exerted on the drone, it would disintegrate even if it didn't hit the airplane. But of course, the air density and curvature is not nearly enough to affect a drone so dramatically. Mooney M20's wing generates only about 15 pounds of lift (down force) per square foot of the wing at cruise speed. If instead of the drone we had a feather (small low density item) and the speed was 5 knots then yes, that might have worked.
k_sze 8y ago
I'm just glad they used gelatin to simulate a bird. As soon as I heard the guy say he wanted to compare the impact of a drone vs the impact of a bird, I was mentally gasping. XD I wonder if the results would have been different if they moulded the gelatin into a bird shape (it's moulded as a cylinder in the video, if I'm not mistaken) because then the pressure would have been different. Of course it would probably have been harder to fire from the air pressure cannon. The block of gelatin also didn't seem to have any hard bits embedded inside. Real birds have bones. While small birds' bones aren't particularly tough, I'm pretty sure the beaks of raptors and some nut-eating birds are tough stuff.
- PaulKeeble 8y ago
  Initially plane parts (engines, wings, cockpits) were tested against dead birds but nowadays we have so many live strikes every year that in practice we know what the proxy based on gelatin is for a variety of birds. Gelatin is harder than flesh but softer than bone and the overall effect is that on average it has the same effect as birds because it is more like an average representation. While parts of birds are relatively tough they aren't in sufficient volume or weight to penetrate any more. That isn't to say a bird strike isn't pretty dangerous because they can be. Jet cockpits get severely damaged by them as do engines and you can see in the video the effect on a wing.
- stevenwoo 8y ago
  Supposed they have used a pneumatic cannon with bird carcasses for testing purposes and Mythbusters tried it with a frozen and non frozen IIRC, though this says clay works just as well. https://www.snopes.com/fact-check/catapoultry/ https://www.snopes.com/fact-check/catapoultry/
arwhatever 8y ago
We need to set about reinforcing the leading edges of airplane surfaces. :-)

102 points by protomyth 8y ago

ars 8y ago

It made a hole and caused internal damage. But would not have taken down the plane. Recommendation to make drones "frangible", so they break on impact and do not penetrate into the wing. In comparison a bird crushed the wing surface but did not cause internal damage.

fermienrico 8y ago
Wings also hold fuel, so it can catch on fire.
- lolc 8y ago
  We're looking at a collision between a big kerosene-tank and a fist-sized Li-Po battery.
  - jtbayly 8y ago
    Sounds like a fun time.
  - karlkatzke 8y ago
    Yeah... the fuel in many GA aircraft is usually inside of a relatively thin rubber bladder inside the wing. It does not self seal. If it leaks, it’s going to run down the back of the aircraft and may drain into the cabin. In some aircraft with engines mounted on the rear of the aircraft it can run towards or into the engine. Now, on top of dealing with an emergency that has disabled control surfaces like ailerons and flaps that pass through the inside of the wing, damaged the leading edge which is critical for generating lift, and potentially having a wing come off if you hit a rough patch of air with a damaged spar, the pilot may have to deal with a fuel leak that would endanger the people in the cabin or cause a midair fire. Not good.
  - sokoloff 8y ago
    Most piston aircraft run on gasoline, which is far more flammable than Jet-A/kerosene.
- deleted 8y ago
  [deleted]
splurge100 8y ago
Now also imagine the drone hit the windscreen, and not the wing. Or went into the prop / engine. Or hit the tail and damaged the rudder. The leading edge of the wing is likely the best case scenario. All others probably result in far more serious consequences.
AmVess 8y ago
The drone penetrated the wing and broke spars. It is very easy for such an impact to also destroy control surface cabling, wiring, or hydraulics which certainly can cause a plane crash.
- JasonFruit 8y ago
  Dented the front spar and some compression members. It probably reduced the wing's margin for maneuvering, but should still have been manageable to get down safely. Not to downplay the danger, but let's not exaggerate it either.
  - murukesh_s 8y ago
    What if the drone was heavier or impacted somewhere else more critical? Drone is pretty much a mini aircraft so it has to be regulated somehow.. which i believe is being done already!
  - AmVess 8y ago
    I am not exaggerating. Several years ago, a bird strike in Alaska resulted in a fatal crash of a 172. Does it happen often? Probably not, but a large heavy drone can easily take down a small civilian aircraft.
    - JasonFruit 8y ago
      I'm just pointing out your exaggeration of the result of this test, not the danger in real life, which I believe you assess accurately.
CPLX 8y ago
That was enough to take down a plane easily. Wings don't just sit there on the ground like in the video, they support the fuselage of the plane against serious aerodynamic forces. They are under load, it's like taking out a bunch of columns at the ground floor of a building. Not to mention that wings are full of fuel, as well as the cables or hydraulic lines connected to the control surfaces.
- jetrink 8y ago
  The engineer that conducted the test concluded that the plane would have been able to survive the impact. However, he said that if the test were conducted on a faster aircraft like a business jet, the results could be worse.
  - geoelectric 8y ago
    Realizing I should go watch the video, did he say at what height it would be recoverable? For example, there's been at least one high-profile plane crash in the past (Lauda Flight 004) where a thrust reverser (diverts the jet output forward instead of backwards, used to slow you down quick during landing) deployed mid-flight. That should have been recoverable, but turns out Boeing only projected outcome at low speeds and altitudes. The outcome at cruising speeds/altitudes turned out to be far different and the plane went down. While cruise wouldn't be an issue (don't think they get up that high!) I'd expect the outcome of a drone hitting a flight control surface might vary between takeoff, landing, and lowish-altitude holding.
- bronco21016 8y ago
  You’d be shocked how little of the wing is actually supporting the entire structure. Typically there is one main spar that holds up the entire wing and the skin and ribs only hold a fraction of the load which is distributed to the spar. As you might imagine the spar is going to be a pretty heavy duty piece of aluminum and not easily damaged by something like this. A wing can sustain a fairly large hole as long as the spar isn’t damaged. Control cables would be a concern but hydraulics and fuel aren’t typically going to be a concern. Fuel isn’t as combustible as everyone likes to think. There are also additional tanks. Hydraulics offer redundancy on aircraft that use hydraulic control surfaces. I’ve seen a Cirrus SR20 hit a deer at takeoff speed and leave a 2.5 ft hole in the skin of the wing the went as deep as the reinforced fuel tank. The aircraft continued flight and came back around and landed just fine. Even flew to the repair airport after cleaning up some loose fiberglass. Personally what worries me more is what would happen if they fired this thing at the plexiglass windscreen. In a GA airplane that would likely be fatal.

jessaustin 8y ago

This type of incident seems unlikely to happen by accident.

SteveNuts 8y ago
Against a commercial airliner you'd pretty much have to be flying right near the runway of the airport, but for a GA Cessna those can be flying pretty much anywhere. I can easily see how a small plane could accidentally hit a drone.
- xstephen95x 8y ago
  yeah and on 9/11 they had to fly right near the twin towers.
  - pavel_lishin 8y ago
    That's a good point - you don't even have to kill anyone to effect a pretty significant scare. How much would it cost to buy enough drones to shut down an airport by having them hover in front of the runways? And how quickly could they be taken down?
    - kungtotte 8y ago
      Unless the drones have onboard AI, all you'd need is to jam the signal. It can't be that hard to shut down drone frequencies seeing as how they have gear to shut down cell phones (to prevent them being used to set off IEDs).
      - pavel_lishin 8y ago
        In my particular movie theater plot, I'm assuming they've been loaded with firmware to just keep station at a particular location in space. Plus, how long would it take to get signal jamming equipment to the runway? Can it be used safely around an airport? Etc, etc. Novel-research stuff.

JoblessWonder 8y ago

Interesting experiment. Looks like a lot of fun to use that air cannon to blast things at things. That aircraft doesn't have any de-icing equipment so it is basically just sheet metal where it hit. I'd be curious to see what would happen if it ran into a wing with than just a thin skin.

sbradford26 8y ago

The sheer amount of airplanes in the sky at anytime is incredible. Also designated no fly zones can change and users may be unaware. So to avoid this issue I think we need to do more than just depend on users knowing where they can fly and not. Drone collides with helicopter in a temporary flight restrictions (TFR) zone: https://arstechnica.com/tech-policy/2017/12/drone-collides-with-us-army-helicopter-puts-1-5-dent-in-rotor/ https://arstechnica.com/tech-policy/2017/12/drone-collides-w... Map of all airplanes currently flying: https://www.flightradar24.com/40.21,-88.24/6 https://www.flightradar24.com/40.21,-88.24/6

inevitable2 8y ago
The sheer volume of the sky at all times is even more incredible!
rootusrootus 8y ago
That's really an ADS-B map, which is not actually all planes flying, at least not yet. It's especially sparse for small private planes, which are probably the most likely to find themselves tangling with a drone.
- sokoloff 8y ago
  Prediction: There will never be a time when all air traffic is ADS-B out equipped. It's certainly not a current mandate, and is only mandated for aircraft desiring access to some select airspace after Jan 1, 2020. I will equip, because I own a hangar inside the mode C veil of Boston, but if I were 6 miles farther out, I may very well choose to avoid class B/C airports and not equip. Lots and lots of traffic will certainly make that choice.
prawn 8y ago
There is a lot of air up there. I fly drones in Australia (https://serio.com.au/ https://serio.com.au/) and it's easy to stay well out of the way of large aircraft (don't launch anywhere near airports, and restrict your maximum altitude) and helicopters (you can hear them from a long way away). DJI's software enforces a survey with local regulations before you can fly. The default settings are all very restrictive too. The authority here provides an app that quickly indicates the flight rules in a particular location - airports and approach paths, non-controlled aerodromes, etc. It's quick enough that it's easy to check as part of your setup procedure. The riskier situations I think are cropdusters (fly very low and launch from rarely used airfields) or sightseeing planes/choppers (operating close to the ground despite launching from a fair distance away). I often fly at this location (https://serio.com.au/media/20180171.jpg https://serio.com.au/media/20180171.jpg) and on weekends there can be vintage sightseeing planes coming down the beach in that bay, definitely below the 120m (400') drone limit.

secabeen 8y ago

I don't know that much about air dynamics. How likely is it that a drone would strike exactly on the leading edge of a wing, as opposed to passing just over or just under the wing?

gist 8y ago
Also (along the lines of air dynamics) I am wondering about whether an airplane has a force in the direction it is traveling in and if that force does push anything small out of the way. As a small example if I have a pot in my hand and I move it in the direction of a tissue the tissue will move. So we have a very large airplane wing moving in the direction of a much smaller drone and the test does not simulate that at all.
- deleted 8y ago
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- dreamcompiler 8y ago
  Two things: 1. Airplane wings are designed not to "push" forward on the air in front of them. That's drag and airplanes are designed to minimize it. 2. What little air is pushed forward is only going to be affected by the oncoming wing a few inches in front of the wing, and at 230 mph closing speed that doesn't provide nearly enough time for the force of the oncoming air to move the drone out of the way.
  - gist 8y ago
    Thanks. But one question. What is the chance that a drone in the path of an airplane will not be impacted by the force of some other object on, or design of, the plane that is not the wing? For example the engine or the landing gear (small plane) or the fuselage? So we hover a drone in front of a small plane and will the small plane hit the drone? And if a larger jet will the drone remain in place or move out of the way by some force (not the wing). And remenber that the drone has to exactly strike in a particular way. As an example (of 'in a particular way') think of a nail on the road. The nail needs to be in exactly the right position to puncture a modern tire. That only happens in a very small amount of cases (or with a screw). Normally if it doesn't randomly happen the nail or screw gets pushed aside and does not puncture the tire. [1] This is not a statement based on expertise I am just offering another point to consider and am curious. [1] This I think is what happens with a paper cut sharp edge and precise angle.

pmilla1606 8y ago

I think 230mph is unrealistic for such tests. A quick google search shows something between 70mph - 100mph on approach [1]. I doubt drones are found at altitudes of aircraft at cruising speed. I'm not saying that this isn't a concern but can somebody with actual aviation knowledge (I have none) chime in and explain the 230mph figure? 1: http://www.mooneyland.com/how-to-land-a-mooney-properly/ http://www.mooneyland.com/how-to-land-a-mooney-properly/

tlb 8y ago
Landing speed for a loaded 737 can be up to 203 mph [0]. Among general aviation, a Gulfstream 450 landing speed can be up to 186 mph at full weight and high altitude. The drone itself can have some speed opposite to the airplane. 230 mph is only a little conservative. [0] http://www.b737.org.uk/vspeeds.htm http://www.b737.org.uk/vspeeds.htm Note that numbers are in knots. [1] http://www.code7700.com/g450_vref.htm http://www.code7700.com/g450_vref.htm
- pmilla1606 8y ago
  But surely a 737 wing is completely different to the one tested here? I'd be very interested to see a 737 wing being tested like this.
  - falcolas 8y ago
    Completely different? No. Still mostly aluminum sheets riveted to spars with a big ol' gas tank in them. Biggest difference is the control cables would be mostly replaced with hydrolic lines.
  - deleted 8y ago
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- bronco21016 8y ago
  Your referenced speeds for the 737 are for an overweight landing at the lowest allowable flap setting. 186 mph for the G450 would also occur at a weight above max landing weight. An incredibly low likelihood.

dsfyu404ed 8y ago

This is not all that much more than the damage done by a Canadian goose. I guess makes sense. The drone has to fly so it can't be built like a tank.

mrguyorama 8y ago

I wonder how easy it would be to make drones have a stronger radar signal? It's probably not nice to clutter up the displays of ATC, but it would be I think a more direct solution for controlled airspace

GaryNumanVevo 8y ago
It's fairly straight forward to implement this. Some modern USAF missiles are built to mimic various planes' radar signatures to suss out any ground-to-air missile defenses before actual planes move in. [0] [0] https://foxtrotalpha.jalopnik.com/the-pentagons-flying-decoy-super-weapon-is-about-to-get-1669729445 https://foxtrotalpha.jalopnik.com/the-pentagons-flying-decoy...
philip1209 8y ago
Radar reflectors are common on certain aircraft or even boats: https://www.gaelforcemarine.co.uk/en/GB/Trem-IOR-Radar-Reflector/m-3603.aspx?PartnerID=22&utm_source=google&utm_medium=shopping&utm_campaign=UnitedKingdom&gclid=EAIaIQobChMIw8Sn6fvq3QIVCpPtCh3ArgWNEAQYASABEgKoefD_BwE https://www.gaelforcemarine.co.uk/en/GB/Trem-IOR-Radar-Refle... They used to equip some stealth aircraft during training with them so they could be more easily tracked.
- Scramblejams 8y ago
  Stealth aircraft deploy them whenever they’re operating in civilian airspace so they can integrate into the existing radar-based ATC infrastructure. They’re called Luneburg Lenses: https://en.m.wikipedia.org/wiki/Luneburg_lens https://en.m.wikipedia.org/wiki/Luneburg_lens

cde-v 8y ago

I'm honestly surprised we haven't seen anyone try to take down a plane by flying a drone into an engine on takeoff.

neuralRiot 8y ago
It turns out, the risk of terrorist attacks are much lower than some agencies want us to believe.
stordoff 8y ago
I was discussing this with someone a few weeks ago, and swarms of drones (flying in formation) are a concern, and the only thing really stopping it is that no one has tried (as neuralRiot says). Unfortunately, I don't really know how you would prevent it.
- baddox 8y ago
  I’m sure it could be done, but I’m also willing to bet there are even easier ways to threaten airplanes that don’t involve relatively new consumer products.

ejo4041 8y ago

My brother actually hit a deer on takeoff a few years ago in Charlotte. It was all over the news that day. It did not do as much damage as this drone did. Mostly just dented in the face of the wing which caused fuel to leak out. It was a little closer to the fuselage. That prompted an emergency landing.

berbec 8y ago
Delta v for the deer was likely significantly lower. The video says impact increases with square of velocity.
bufferoverflow 8y ago
How does a deer hit the wing? Aren't they rather high? A small plane that's much slower on takeoff/landing than a commercial airliner?
rasz 8y ago
>It did not do as much damage as this drone did. probably wasn't shot out of air cannon at 230mph

zokier 8y ago

I guess it would depend on if it is this sort of drone: https://defensesystems.com/articles/2017/05/02/~/media/GIG/Defense%20Systems/22mq25aboardaunnavyaircraftcarrier%201.jpg https://defensesystems.com/articles/2017/05/02/~/media/GIG/D... or this sort https://api.ning.com/files/LxgTrYw8IckDE2ljSVm61iv7MVev4tELr4SQs5fDfPCCGgJEr8F6wV9IgLRaqzvX8Yr8UMSmcYPmgNHxSTWad*1y1neY7WEV/DSC_8004.JPG https://api.ning.com/files/LxgTrYw8IckDE2ljSVm61iv7MVev4tELr...

mothsonasloth 8y ago

A year ago I saw someone flying a drone from the top of the Shard building in London. The person was promptly told to land his drone immediately by the security. However the scary thing for me is that the smaller business planes and commercial plane that fly into London city go really close to the Shard on their approach. So definitely a collision is now a real risk

DominikPeters 8y ago

I enjoyed that the expert's recommendation was not "regulation", but to change drone design so they more easily break apart on impact. More likely to be implemented and does not need enforcement on the consumer level.

mxuribe 8y ago
Well, there go my plans to build an adamantium drone! :-p (I know, i know, adamantium is not real...)
- StavrosK 8y ago
  Even if it were real, you'd get a ~3 minute flight time, so eeeeeh.
cco 8y ago
I would also support drone manufacturers self regulating via GPS deadzones in designated no fly areas. Nearly all drones of a meaningful size are GPS enabled and could be disabled in range of a no fly zone. Yes it could be spoofed, yes it would require some effort from manufactures, but self inflicted regulation as an industry here could pay dividends if the alternative is ham fisted regulation following a drone/airplane catastrophe.
- NiekvdMaas 8y ago
  That's exactly what all major drones do. DJI has a market share of about 75% [1] and you cannot take off any of their success in a restricted flight zone. Flight zone updates are also mandatory and forced to the users. Same for Yuneec, which has another 5% market share. 1. http://thedronegirl.com/2018/09/18/dji-market-share/ http://thedronegirl.com/2018/09/18/dji-market-share/
  - cco 8y ago
    Ah interesting, I didn't know!
8y ago

airuser0 8y ago

It's similar to the question asked here before: "Can a dog kill a man with a cane?". I personally accepted the answer:"Depends on the dog, depends on the man, and depends on the cane".

saalweachter 8y ago
“How is the dog holding the cane?”

foxylad 8y ago

I'm concerned that the test uses a static wing. If you drop a fishing float directly in front of an obstacle in a river, it will be moved with the water around the obstacle, not hitting it. Air is a lot less dense than water, but my instinct is that unless the drone hit a very narrow sweet spot it would simply be swept around the wing. And even in that sweet spot, there will be a buffer of compressed air that would substantially slow the impact. Could someone with more knowledge of fluid dynamics comment on the applicability of static tests like this to actual aircraft damage?

Splines 8y ago
I do not have a fluid dynamics background, but my hunch is that at the speeds involved, and the fact that there is a column of air from the cannon already surrounding the projectile, that this makes this simulation close enough.
- foxylad 8y ago
  Ah, good point about the air column.
grogers 8y ago
Does a baseball move out of the way of the swinging bat? There might be some small effect, but it's not the dominant one. In this scenario the wing is just a slightly bigger bat, and the drone is a slightly bigger ball. It would of course take a very (un)lucky strike to collide dead on like this, but not that unreasonable. I do hope they test indirect strikes too though.
- jessriedel 8y ago
  I think you're probably right, but note that even for a powerful hitter, bat speed is ~80 mph. This is significantly less than 238 mph used in the video as a typical airplane speed.
raquo 8y ago
Air movement is a rounding error in this test. Suppose the curvature of the wing's airflow could in fact push the drone 15cm up or down in the time it takes the wing to advance 30cm forward (a tiny fraction of a second). That would require such a high G load exerted on the drone, it would disintegrate even if it didn't hit the airplane. But of course, the air density and curvature is not nearly enough to affect a drone so dramatically. Mooney M20's wing generates only about 15 pounds of lift (down force) per square foot of the wing at cruise speed. If instead of the drone we had a feather (small low density item) and the speed was 5 knots then yes, that might have worked.

k_sze 8y ago

I'm just glad they used gelatin to simulate a bird. As soon as I heard the guy say he wanted to compare the impact of a drone vs the impact of a bird, I was mentally gasping. XD I wonder if the results would have been different if they moulded the gelatin into a bird shape (it's moulded as a cylinder in the video, if I'm not mistaken) because then the pressure would have been different. Of course it would probably have been harder to fire from the air pressure cannon. The block of gelatin also didn't seem to have any hard bits embedded inside. Real birds have bones. While small birds' bones aren't particularly tough, I'm pretty sure the beaks of raptors and some nut-eating birds are tough stuff.

PaulKeeble 8y ago
Initially plane parts (engines, wings, cockpits) were tested against dead birds but nowadays we have so many live strikes every year that in practice we know what the proxy based on gelatin is for a variety of birds. Gelatin is harder than flesh but softer than bone and the overall effect is that on average it has the same effect as birds because it is more like an average representation. While parts of birds are relatively tough they aren't in sufficient volume or weight to penetrate any more. That isn't to say a bird strike isn't pretty dangerous because they can be. Jet cockpits get severely damaged by them as do engines and you can see in the video the effect on a wing.
stevenwoo 8y ago
Supposed they have used a pneumatic cannon with bird carcasses for testing purposes and Mythbusters tried it with a frozen and non frozen IIRC, though this says clay works just as well. https://www.snopes.com/fact-check/catapoultry/ https://www.snopes.com/fact-check/catapoultry/

arwhatever 8y ago

We need to set about reinforcing the leading edges of airplane surfaces. :-)