Can a UAV bring down a plane?

[oldcelt]

In my opinion, there is little doubt that cheap availability combined with the easy flying characteristics of modern drones has contributed to the current dangers being experienced or anticipated both to air traffic and ground based installations and people.

Commercial aircraft carry a ‘black box’ which, I’m sure, all you wise folks out there know about. It must be possible to create a miniature, simplified ‘black box’ to be fitted to every drone. It would need only the following functions:-

1. The drone will not fly without it being activated. On purchase its identity, together with the owner’s details, must be recorded with the CAA; the FAA or whichever is the responsible authority in each country to trigger activation (this could be automated via the internet). It would mean that the owner/pilot can be traced in the event of a serious accident. If sold to a third party, the new owner’s details must be notified by the seller to the authority. Nobody is going to be so stupid as to leave themselves responsible for a drone after selling it.
2. It would emit an identifiable short-range signal transmitted at all times when airborne. This signal (like a transponder in commercial aircraft) would simply be intended to enable the craft to be identified if it infringes controlled airspace.

Such a device would, of course, increase the price of every drone. Maybe not such a bad thing since it might deter some of the most irresponsible buyers from ever owning a drone.

There will never be a perfect solution of course. However, this idea may go a long way towards improving air safety and, incidentally, the public image of drone flying.

As things stand there have been some very scary and dangerous near misses in the last year or so. As drone ownership increases so must the risks so perhaps this idea is not so draconian as may first appear.

 

[AnzacJack]

Correct. If you consider a kite an aircraft? At most a drone would take down another drone of similar size.



You know no such fact! "Imagine" being the operative word. May I refer you to Newtons Third Law and ask you to consider a drone similar in size to the mavic pro flying at full speed towards a bus traveling at 60km-100km/hr towards the mavic - you're not suggesting the mavic would penetrate the windscreen glass of that bus?? There are simply to many variables in favour of the moving bus.



With a due respect, being 'pretty sure' from witnessing bird strikes over 40 years of aviation has no factual baring on the issue and is merely speculation.

Tired of the scaremongering.

I think my experience with bird strikes and other aircraft incidents gives me the credibility to have an educated opinion.
I’m not interested in scare mongering, just commenting on a post that asks a question.
You sir seem to be a fool. This is also my opinion based on the fact that I have spoken to fools before and I am pretty sure you are one.

 

[Classic flyer]

Just another point... anyone who thinks a drone can't bring down a plane and that this is scare mongering is delusional. Just see the result of bird strikes on cockpit windows or on a engine.
Losing power on one engine during take off can be disastrous.
I really dont get the ignorance!

Read about US Airways flight 1549 if you dont believe it, or how about reading : Bird strike - Wikipedia

Try to be informed and dont give ignorant answers, Thanks!
Raphael

Some of these guys apparently have no aviation background...I also have been in the business 36 yrs as a structural mechanic and have many hrs of repairing aircraft that suffered heavy damage do to birdstrikes

 

[Classic flyer]

I'm intrigued. Is this a serious post or are you just having some fun here?

Sounds like a pinhead to me...just saying

 

[Classic flyer]

In my opinion, there is little doubt that cheap availability combined with the easy flying characteristics of modern drones has contributed to the current dangers being experienced or anticipated both to air traffic and ground based installations and people.

Commercial aircraft carry a ‘black box’ which, I’m sure, all you wise folks out there know about. It must be possible to create a miniature, simplified ‘black box’ to be fitted to every drone. It would need only the following functions:-

1. The drone will not fly without it being activated. On purchase its identity, together with the owner’s details, must be recorded with the CAA; the FAA or whichever is the responsible authority in each country to trigger activation (this could be automated via the internet). It would mean that the owner/pilot can be traced in the event of a serious accident. If sold to a third party, the new owner’s details must be notified by the seller to the authority. Nobody is going to be so stupid as to leave themselves responsible for a drone after selling it.
2. It would emit an identifiable short-range signal transmitted at all times when airborne. This signal (like a transponder in commercial aircraft) would simply be intended to enable the craft to be identified if it infringes controlled airspace.

Such a device would, of course, increase the price of every drone. Maybe not such a bad thing since it might deter some of the most irresponsible buyers from ever owning a drone.

There will never be a perfect solution of course. However, this idea may go a long way towards improving air safety and, incidentally, the public image of drone flying.

As things stand there have been some very scary and dangerous near misses in the last year or so. As drone ownership increases so must the risks so perhaps this idea is not so draconian as may first appear.

Sounds like a solid idea to me

 

[BigEegit]

I think my experience with bird strikes and other aircraft incidents gives me the credibility to have an educated opinion.

Please do not get me wrong. I don't doubt your credibility and apologies if you believed so. But you must accept that bird strikes are not the same as drone strikes.

I’m not interested in scare mongering, just commenting on a post that asks a question.

I accept that you are not interested in scaremongering. But when one erroneously presents what they believe to be worst case scenarios as fact, it serves no purpose other than to create fear. That is scaremongering in my opinion.

You sir seem to be a fool. This is also my opinion based on the fact that I have spoken to fools before and I am pretty sure you are one.

Please keep to the thread.

 

[BigEegit]

Just another point... anyone who thinks a drone can't bring down a plane and that this is scare mongering is delusional. Just see the result of bird strikes on cockpit windows or on a engine.Losing power on one engine during take off can be disastrous.
I really dont get the ignorance!

Read about US Airways flight 1549 if you dont believe it, or how about reading : Bird strike - Wikipedia

Try to be informed and dont give ignorant answers, Thanks!
Raphael

You wish for one to be informed on drone strikes by informing them on bird strikes??

 

[Classic flyer]

You wish for one to be informed on drone strikes by informing them on bird strikes??

There is really no difference ...just that one is a bird and the other a drone... end result is the same

 

[sar104]

There is really no difference ...just that one is a bird and the other a drone... end result is the same

And what difference there is - primarily the rigidity and density of the components - then at least weight for weight it makes the drone a significantly bigger threat, exerting much higher forces at impact for equivalent changes in momentum.

 

[oldcelt]

There is a lot of data relating to bird strikes but little, if any reliable data, relating to drone strikes. As a professional engineer and retired military flying instructor, I suggest that damage resulting from a mid-air strike, whether bird or drone, would not be too dissimilar. A mute swan, for example, has, in my opinion, more potential energy than a Mavic Pro (mute swan average weight: 23-26lbs: Mavic Pro. weight 1.62lbs). It has been reported that a mute swan can fly at up to 50mph!!

Bird strikes have been experienced by commercial jet aircraft in relatively large numbers over several years and successful recoveries made. Much would depend on the aircraft (commercial jet or, for example, Cessna 152) and where the impact actually occurred in the event of a strike. Any solid object smashing through the windscreen of a light aircraft could be fatal if it disabled the pilot. Commercial aircraft have two pilots and a great deal of redundancy built into the systems. Even ingestion into a jet engine is unlikely to cause more than emergency procedures being implemented because of the safety factors built in. Total failure of the engine concerned is likely to be the worst scenario and commercial jets can be flown on the remaining power units. Consequential damage is unlikely, although I have to admit not impossible.

Any sensible development to control irresponsible flying is to be welcomed. However, we do need to be careful not to go overboard and create impossibly restrictive practices for all who enjoy every aspect of aviation.

 

[sar104]

There is a lot of data relating to bird strikes but little, if any reliable data, relating to drone strikes. As a professional engineer and retired military flying instructor, I suggest that damage resulting from a mid-air strike, whether bird or drone, would not be too dissimilar. A mute swan, for example, has, in my opinion, at least as much potential energy as a Mavic Pro. Bird strikes have been experienced by commercial jet aircraft in relatively large numbers over several years and successful recoveries made.

Much would depend on the aircraft (commercial jet or, for example, Cessna 152) and where the impact actually occurred in the event of a strike. Any solid object smashing through the windscreen of a light aircraft could be fatal if it disabled the pilot. Commercial aircraft have two pilots and a great deal of redundancy built into the systems. Even ingestion into a jet engine is unlikely to cause more than emergency procedures being implemented because of the safety factors built in. Total failure of the engine concerned is likely to be the worst scenario and commercial jets can be flown on the remaining power units. Consequential damage is unlikely, although I have to admit not impossible.

Any sensible development to control irresponsible flying is to be welcomed. However, we do need to be careful not to go overboard and create impossibly restrictive practices for all who enjoy every aspect of aviation.

It's true that there have been few studies of drone impact but the broader field of impact studies across a wide range of applications provides much useful information, both theoretical and experimental.

In terms of energy available to deposit on impact, the swan you mention (≥ 10 kg) has over an order of magnitude more kinetic energy (I assume that you meant kinetic, not potential energy) and momentum in the collision frame of reference. That makes the swan a more energetic and higher impulse (momentum change) impact, but total energy and/or impulse are not good parameters with which to characterize many of the relevant damage mechanisms. While there will be a threshold energy needed, rate of deposition of energy (power) and rate of change of momentum (force) are much more important. That's why, for example, a small, light stone can break a windshield while a much heavier bird will just bounce off with no damage. Rigid objects have much higher compressional strength and modulus and therefore, during an impact, exert much higher forces for a shorter duration than softer objects, which exert lower impact forces of longer duration.

So in this comparison, it's not obvious which will be worse, a 10 kg swan or a 0.75 kg Mavic, but that's not much consolation because a 10 kg swan is a very serious impact to any part of an airframe. However, I can say with complete certainty that a Mavic will cause much more damage than a 1 kg bird.

The other thing that I would say is that it's not a useful argument to say that a drone impact probably won't bring down an aircraft, or will probably only lead to an engine failure and emergency landing. That applies equally to all the "it's not the worst thing that could happen" arguments that are regularly trotted out in these discussions.

 

[oldcelt]

I pretty well agree with all you say. I avoided using the term kinetic energy because that varies with velocity. I deliberately meant the potential energy which is inherent in each object due to its configuration or position. Kinetic energy is more difficult to assess since we have no idea of the velocity of either object at impact, although the swan (for the sake of argument) will have greater kinetic energy than a drone (of the type under discussion) at equal rates of motion.

Your point about rigidity is of course exactly right. However, I'd like to see some empiric data obtained from actual tests to support your assertion:- "I can say with complete certainty that a Mavic will cause much more damage than a 1 kg bird", although I suspect you're right. However, a 10 kg bird is a completely different kettle of fish. We are, of course, at the moment ignoring the point of impact on the manned aircraft and the different configurations and stresses within it. That could be of some significance.

There were some tests carried out at Farnborough many years ago using chickens which produced the most unexpected results if I remember correctly. Unfortunately, as I approach my 84th birthday, my memory is not up to remembering the specific data or where to research for it.

I have to take issue with your final paragraph. My comments were not intended to be used to draw any conclusions about whether or not it matters if there happens to be a bird or drone strike. I was merely stating a fact: i.e. commercial airliners can fly safely with an engine out - fact!

The other bit is my personal opinion in that I think it unlikely that a strike through the engine intake would cause any collateral damage to adjacent engine(s) or to the airframe. Again, I know of no experimental data to support the view and it is, as I said earlier, merely my opinion. An observation; not intended to be used to try and prove anything.

It's a fascinating subject and I do believe there has been some work done in testing for just this eventuality. If I get some time, I'll try to contact some of my old friends from my RAF days to see what we can dig up.

 

[sar104]

I pretty well agree with all you say. I avoided using the term kinetic energy because that varies with velocity. I deliberately meant the potential energy which is inherent in each object due to its configuration or position. Kinetic energy is more difficult to assess since we have no idea of the velocity of either object at impact, although the swan (for the sake of argument) will have greater kinetic energy than a drone (of the type under discussion) at equal rates of motion.

Your point about rigidity is of course exactly right. However, I'd like to see some empiric data obtained from actual tests to support your assertion:- "I can say with complete certainty that a Mavic will cause much more damage than a 1 kg bird", although I suspect you're right. However, a 10 kg bird is a completely different kettle of fish. We are, of course, at the moment ignoring the point of impact on the manned aircraft and the different configurations and stresses within it. That could be of some significance.

There were some tests carried out at Farnborough many years ago using chickens which produced the most unexpected results if I remember correctly. Unfortunately, as I approach my 84th birthday, my memory is not up to remembering the specific data or where to research for it.

I have to take issue with your final paragraph. My comments were not intended to be used to draw any conclusions about whether or not it matters if there happens to be a bird or drone strike. I was merely stating a fact: i.e. commercial airliners can fly safely with an engine out - fact!

The other bit is my personal opinion in that I think it unlikely that a strike through the engine intake would cause any collateral damage to adjacent engine(s) or to the airframe. Again, I know of no experimental data to support the view and it is, as I said earlier, merely my opinion. An observation; not intended to be used to try and prove anything.

It's a fascinating subject and I do believe there has been some work done in testing for just this eventuality. If I get some time, I'll try to contact some of my old friends from my RAF days to see what we can dig up.

Thanks for clarifying your comments. On the kinetic vs. potential energy issue, potential energy in this context only arises from position in the earth's gravitational field, described by the well-known form mgh where m is the mass of the object, g is the acceleration due to gravity (9.81 m/s²) and h is the height above the ground. That doesn't have any relevance to such an impact since the impact does not immediately change h.

The kinetic energy term (½mv² or more accurately ½mΔv²) is the available energy since v changes rapidly on impact. One can take the velocity, v, in question, to be the impact velocity which is going to be close to the speed of the aircraft since that will typically be much greater than the speed of the bird or drone.

I agree that it would be very desirable to have some direct experimental data comparing impacts of drones (or representative structures) with the impact of birds on various surfaces as a function of drone and bird mass. That would allow a more quantitative assessment than my qualitative "weight-for-weight, drones will do more damage".

 

[oldcelt]

I have no argument with your statements. I was simply trying to keep the discussion on a level which could be understood by our friends here who may not be qualified in physics or engineering to that standard.

Enjoyable discussion, thanks!

 

[Classic flyer]

I have no argument with your statements. I was simply trying to keep the discussion on a level which could be understood by our friends here who may not be qualified in physics or engineering to that standard.

Enjoyable discussion, thanks!

You guys a r e friggin Awsome

 

[AnzacJack]

Please do not get me wrong. I don't doubt your credibility and apologies if you believed so. But you must accept that bird strikes are not the same as drone strikes.



I accept that you are not interested in scaremongering. But when one erroneously presents what they believe to be worst case scenarios as fact, it serves no purpose other than to create fear. That is scaremongering in my opinion.



Please keep to the thread.

Keep to the thread, by answering the OP’s question?
As long as you agree on the comments?
I am wondering on the basis of your vast knowledge, where you feel you can refute the opinions of others that have real world experience with aircraft structures.
The question is not about probability, it’s about possible outcomes

 

[Classic flyer]

Keep to the thread, by answering the OP’s question?
As long as you agree on the comments?

You are correct sir

 

[Obi~wan]

You guys are going deep.

 

[Classic flyer]

You guys are going deep.

Lowe got the "HEAVY HITTERS" INVOLVED NOW

 

[BigEegit]

"You sir seem to be a fool. This is also my opinion based on the fact that I have spoken to fools before and I am pretty sure you are one"

Keep to the thread, by answering the OP’s question?

Keep to the thread by not calling people fools for disagreeing with your baseless assertion.