![](https://hackadaycom.files.wordpress.com/2016/11/droneexplode_feat.png?w=800)
From Hackaday:
Ignore the article, watch the video at the top of the page. The article is about some idiot, likely not even a hacker, who bought a drone somewhere and nearly rammed it into a plane. He managed this with concentrated idiocy, intention was not involved. While these idiots are working hard to get our cool toys taken away, researchers elsewhere are answering the question of exactly how much threat a drone poses to an airplane.
https://hackadaycom.files.wordpress.com/2016/11/droneexplode_thumb.png?w=250&h=250 250w, https://hackadaycom.files.wordpress.com/2016/11/droneexplode_thumb.png 714w" sizes="(max-width: 400px) 100vw, 400px" />Airplanes are apparently armored to withstand a strike from an 8lb bird. However, even if in a similar weight class, a drone is not constructed of the same stuff. To understand if this mattered, step one was to exactly model a DJI Phantom and then digitally launch it at various sections of a very expensive airplane.
The next step, apparently, was to put a drone into an air cannon and launch it at an aluminum sheet. The drone explodes quite dramatically. Some people have the best jobs.
The study is still ongoing, but from the little clips seen; the drone loses. Along with the rest of us.
Perhaps the larger problem to think about right now is how to establish if a “drone” has actually been involved in an incident with a passenger aircraft. It seems there are a lot of instances where that claim is dubious.
Comments
James the time of exposure to the risk is the basis of likelihood. Despite this, the consequence for most airline components, of the "residual risk" of the impact energy from a Phantom, is insignificant. The resulting overall risk is negligible, for a Phantom, which is also the base case for this study and this discussion thread.
We can redefine the sample scope to include other "drones", but with that we also need to redefine the likelihood of such an occurrence, which means that the time of exposure to this type of risk would be orders of magnitude less than that of a Phantom. (which is why the study presumes that the highest likelihood of an incidence is with the most popular Phantom). This means that there is a even smaller chance of a heavier, stronger, "badder" drone impacting an airliner. (let alone that these cost more, aren't typically flown by unskilled Joe public, especially around airports etc etc)
The same applies for the period of exposure to the risk of drone impact, as well as the likelihood of unrecoverable drone impact, that would apply to takeoff and landing procedures. If the number of drones are limited in a airport zone, which many are btw with DJI airport flight restriction zones etc, then the likelihood is also reduced of a unintentional accidental impact, which directly results in a lower risk overall. On top of this an airliner is flying at at half speed in these areas resulting in less impact energy as well.
From what I can tell the study is intention agnostic. An intentional impact of a drone with an airliner throws all the studies presumptions out the window, and another sample dataset would apply, which would need to incorporate the ability of the user to intentionally modify or target the drone to the intended impact (aka add an explosives or IR tracking). This is not an "accident", this could be a slow guided missile! There are many ways that fatalities can result from such intentions, regardless of the safeguards set in place by regulation or safety controls. Such ill intent can also occur by just hiring a moving truck and finding a crowd, a drone is not immune from such evil intent, but it is most definitely beyond the scope of this study (or the results presented).
To be clear, I'm not advocating a free for all, rather that the data needs to be carefully analysed and the best safety and control approach identified. In my opinion a sub 2kg platform limit for pubic use should offer a significant level of safety for both airliners and GA alike, as well as a usable size for drone consumers, and also so happens to be the opinion of the Australian Aviation authority CASA too.
While the test might show a phantom the rules aren't phantom specific. They apply to any UAV including heavy walled carbon fiber / aluminum lawnmowers. The concern is mostly within control areas when commercial aircraft are descending and ascending and at their most vulnerable.
I think the extent of damage, and the likelihood of an indecent with an airliner is being exaggerated here in the comments.
The argument for airliner is not the same as for smaller General Aviation aircraft, that fly slower, lower and with a lot less people on board. It's time for a reality check people.
1) Airliners do not operate at low altitudes for extensive periods, nor in low altitudes at high speeds. Takeoff, landing, approach and climbout within the first 3-6000ft is typically at under 400kmh. Their cruise altitude, where they also spend 95% of their flight time (apart from being safely parked on the ground out of harms way of pesky flying drones) is way beyond the reach of 99.99% of public drones/UAV's, and 1000% out of range of a Phantom (unless it's fusion powered of course!). Let alone the pilot would have to be as lucky as winning the lottery to actually exactly hit a critical location, where it could potentially cause a fault that leads to an uncontrolled airliner landing. Airliners are not that weak...and birds are much bigger and structurally superior to dinky toy Phantoms. There's comparatively little impact energy from a Phantom.
2) Despite the low likelihood of incident explained above there are not many "flight critical" components that are exposed to damage from the front of an airliner. Cockpit windows, pitot sensors etc are all not flight crucial components. Relatively small 747 cockpit windows are 3" thick and weigh 50kg, they are comparable to ballistic glass (think of the pressure area of a bullet at x time mach, and then a Phantom motor etc at maybe 450kmh) and even if a Phantom could penetrate a glad wrap windscreen, and decapitate a pilot, there would still be another pilot! Control surfaces are also protected by the entire surface of the wing, because they are mounted on the rear, not the front.
3) As for engine damage this is a red herring as well. Turbine intake blades, like the composites used on the 777 are 3x stronger than titanium, and spin around at an incredible Mach 1.5. These things are designed to survive such a 50lb blade coming off, at that velocity, without bringing down the aircraft. A 2kg ABS Phantom, will barely even nick the paint on one of those things, let alone that there would be some 4-5 turbine blade strikes per Phantom (so 1/5 of the impact energy too), which would chop it into bite sized bit's that can easily go through the rest of the turbofan or even turbine. It's 4lb Phantom vs 127,000 lb thrust blender, and we're worried who will win?? (btw the blade is producing 450lb of thrust per surface area of the 4lb Phantom)
4) As for GA aircraft, the risk of injury is lower due to fewer people being exposed to the risk, and the significantly reduced velocity of impact, and impact area. Passenger miles in airlines are orders of magnitude greater than GA, and birds order's of magnitude more likely to hit an airplane, and common, than Phantoms! (they don't sell as well as birds lay eggs! ;-) )
Check out this video of a standard car windscreen hitting a bird at 300kmh (which is faster than a Cessna btw).
What I thought was interesting is that they didn't even shoot a complete Phantom out of their test cannon, only parts...despite that it seems everyone thinks that the Phantom disintegrated on impact, leaving nearly no damage, and yet the discussion ensues that Phantoms are dangerous to airliners? Talk about chasing ghosts.
Kind of a crazy debate. Even if 10 phantoms went through a jet engine without a catastrophic failure nobody here wants to be flying in the 11th. Beyond that there is a huge variety of construction materials and geometries in drones so the variables is just too varied to every be able to properly know the risks. Anybody that is flying around an airport or at altitudes that risk an aircraft should be charged with attempted murder. Kind of feels like the stupidity required to drop cinder blocks off a highway overpass.
@ Giovanni,
It is definitely my expectation that a Phantom getting sucked into the intake of a big jet would at least shut down the engine with internal damage and possible, depending on the throttle state of the engine at the time result in a spectacular and rapid self disassembly.
But a simulation is not the same thing.
At some point somebody actually needs to do it for real on purpose maybe even a few times at various throttle settings just to illustrate what will really happen and to clarify for the public why it really is necessary to keep these things away from aircraft.
The other things really worth knowing is the effect they would have on wind screens and props.
The other stuff may cause some damage, but those are the ones that might kill you.
The people on this site are actually serious about the value of "drones" and want to see them made use of effectively and safely and the biggest threat we have is going to be from uninformed consumers doing stupid things that will get restrictions and regulations nobody wants.
A good clear video of a jet engine exploding at high performance take off throttle at maximum plane weight from a Phantom going in the intake should make it clear to even the dumbest "drone" user that aircraft and "drones" don't mix.
(Come on Boeing donate an engine to science!)
Best Regards,
Gary
@Marc It has been simulated: http://diydrones.com/profiles/blogs/simulation-of-8-lb-drone-being-...
It's not a surprise that a typical quadcopter sucked into a jet engine it will probably lead to catastrofic engine failure.
The test craft used in the air cannon video it's clearly not a drone.
Intriguing video, at least we've learned something : not sure if it proves that a drone can damage a 747, but it surely proves that a 747 can damage a drone :)
Um in that "actual test" it says they fired "drone components" to "simulate" an impact...
So they spent many $10k's on modelling and simulating a drone strike on the computer, but could only afford to shoot some of the drone parts through the air cannon for a real test?? From the looks they actually shoot the components individually and not mounted together in any way (or does the cannon acceleration separate it before impact?)
Either way it's not really any kind of test IMHO....at least not the parts that are shown in the video.
I am currious as to the speed used for tests. Take off speed or high altitute cruise speed.
Gary: Hint. You can fly the Phantom remotely at the engine. ;)
I believe this "news" is about 6-12 months old. I know I saw it some time ago.
I suspect the reason why we are not seeing results from these tests, is because nothing happens. They don't want to burst the regulatory bubble by admitting there is no real issue.