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Posted
Of greater interest to the light plane pilot is the kinetic energy to be dissipated as a result of the collision. And the kinetic energy is found by KE = 1/2 mv 2 (sorry, that's supposed to be v squared) So the speed of the drone has a greater effect than its mass, and I'm guessing most drones are fairly slow.

Bruce

 

But it is the closing speed that matters, not the drone's speed.

Actually the effects of collisions are explained by the Law of Conservation of Momentum. The total momentum of a system after a collision is equal to the total momentum of the system before collision.

 

Momentum = mass * velocity

 

Therefore:

 

m1v1 + m2v2 = m1v1' + m2v2'

 

where

 

m1 and m2 are the masses of the bodies

 

v1 and v2 are their respective velocities before the collision

 

v2' and v2' are their respective velocities after the collision.

 

This is for an inelastic collision where no energy is dissipated through distortion of the bodies; sound generation, or heat of friction.

 

In a collision, the velocities of the bodies is changed (v1 - v1'). A collision occurs over time, t. Therefore, in a collision the bodies are accelerated (or decelerated depending on the post impact velocities).

 

If a mass is accelerated by the action of a force on it, so the force one body exerts on the other body by a collision is {m1 *(v1 - v1')}

 

Say a grasshopper weighs 10 grams (0.001 kg) and flies directly at a 1000 kg mass car at a velocity of 2.77 (10 kph) metres per second. It has a momentum of (o.001 * 2.77) kg m/sec = 0.00277 kg m/sec.

 

If the car has mass of 1000 kg and is travelling at 100 kph (27.7 metres per second), it has a momentum of (1000 * 27.7) kg m /sec = 27700 kg m /sec. That's a 10 million times difference in momentum.

 

The kinetic energy of the grasshopper before the collision is 0.5 * (0.001 * 2.77^2) = 0.5 * (0.001 * 7.67) = 0.0038 kg m^2/s^2 = 0.0038 Joules.

 

The kinetic energy of the car before collision is 0.5 * (1000 * 27.7^2) = 0.5 * (1000 * 767) = 0.5 * 767000 = 383645 Joules.

 

OME

 

Too much brain work! I'm going off to have dinner!

 

 

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Posted
a 1.5Kg drone will do no more damage than a 1.5 kg bird... its called physics. force =mass x speed. also, the hundreds of thousands of drones already flying.. as still, not one actual recorded event of a drone strike. i have been doing a uni research assignment on this very issues. and all i can find in official reports, and investigations, is there isnt an issue.. so, if everyone has seen them, or had a near miss, why are you NOT reporting it? all whinge and carry on about the drone problem, but pilots are making no effort to report, so real data can be gathered to do something about it. or we just continue making laws based on emotion and un substantiated fear.

 

in my well over 1000 hrs flying, i have had more close encounters with small balloons than anything else.

Mmmmm, have a look on YouTube. Carbon winglets come off quite easily.

 

 

Posted
Virtually all current drones have the equipment and capability built in to restrict its operations. DJI recently enacted some of that in the US and parts of Europe.

You're being very selective in your meaning of the word drone.

 

Drone does not just mean latest quadcopter. It also encompasses fixed wings, helicopters ( I mean by this standard main rotor and tail rotor type helicopters ), multi rotors with absolutely no guidance systems at all, multi rotors with minimal guidance systems right through to the ones with full GPS autonomous capability. The old style model airplane is a drone.

 

I doubt very much that "most" in a statistically correct sense have systems that have a capacity to be limited. Certainly some have but I'd bet "most" don't.

 

 

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Posted
Mmmmm, have a look on YouTube. Carbon winglets come off quite easily.

have a look further into that video, and you might find it was a viral video made by a special effects company to sell its special effects skills.

also wouldnt you think that taking a winglet off a B737 would have made the real news pretty quickly, or at least, resulted in an ATSB investigation or report?

 

 

  • Agree 1
Posted

Did not look that closely. I know how much mess a bird can make.

 

A recent one had the engine disappearing on a Maverick.

 

A Bantam last year may also had one. Fatal.

 

Yes a light drone could do it.

 

A spinner comming off will take a blade off a prop.

 

Chas

 

 

Posted
You're being very selective in your meaning of the word drone.Drone does not just mean latest quadcopter. It also encompasses fixed wings, helicopters ( I mean by this standard main rotor and tail rotor type helicopters ), multi rotors with absolutely no guidance systems at all, multi rotors with minimal guidance systems right through to the ones with full GPS autonomous capability. The old style model airplane is a drone.

I doubt very much that "most" in a statistically correct sense have systems that have a capacity to be limited. Certainly some have but I'd bet "most" don't.

That is a very pedantic response. It is evident that the theme of the thread is in regard to recreational craft, as depicted by the sensationalist media, not the broad range you suggest.

 

 

Posted

It seems to be an expensive selfie stick without the lightning rod effect.

 

 

Posted

the kids love them, no idea what happens with them when they lose contact with the pilot

 

imagine hitting this monster in your drifter *ouch*

 

 

 

Posted

On the bright side.....you don't get good selfies above 500 agl.

 

Or....maybe I could get it to follow the Drifter....suck on that CASA, no GoPro mounts.

 

 

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Posted
Virtually all current drones have the equipment and capability built in to restrict its operations. DJI recently enacted some of that in the US and parts of Europe.

Mate of mine was just telling me, has a DJI drone (a good drone and only $2300 retail here in Oz) and lives within a kilometre of our international airport. His drone just stopped working a few weeks ago at his home and turned out the aforementioned limitation had been embedded in the software upgrade he did.

 

After a bit of snooping on the internet he ( very non-techy guy) and his 12 year old son found the cause, found a fix and uploaded it and he is back in the air. For free, within a few minutes, he's flying again - within controlled airspace, not far off the glide slope and completely illegally. 12 year old son happily flies it as high as he can get it. But he doesn't see a problem. Just an inconvenience to him that he had to disable the safety limiter software.

 

So much for that!

 

 

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Posted
Mate of mine was just telling me, has a DJI drone (a good drone and only $2300 retail here in Oz) and lives within a kilometre of our international airport. His drone just stopped working a few weeks ago at his home and turned out the aforementioned limitation had been embedded in the software upgrade he did.After a bit of snooping on the internet he ( very non-techy guy) and his 12 year old son found the cause, found a fix and uploaded it and he is back in the air. For free, within a few minutes, he's flying again - within controlled airspace, not far off the glide slope and completely illegally. 12 year old son happily flies it as high as he can get it. But he doesn't see a problem. Just an inconvenience to him that he had to disable the safety limiter software.

So much for that!

So then, can we all assume that you've informed your mate of the error of his ways, the legal and physical consequences of not just being caught, but potential danger to aircraft and human lives?

 

 

Posted

Yep of course I did. Especially given that I fly in and of that airport - although a bit less now than I used to.

 

But like a lot of non-aviation people he sees no justification in the rules. He happily said he never flies it over 500 ft. (Even though the law says 400 ft but has only the GPS altimeter as a way of establishing that altitude anyway) Then in the next breath agreed that if it malfunctioned it could climb to any height and also that his son likes to make it climb straight up as high as he can get it.

 

His attitude is definitely common.

 

 

Posted

Ozrunways has new app which attempts to let users know if they are in area suitable for drone use

 

 

Guest Howard Hughes
Posted
Ah, you have opened a can of worms here!!! My husband is both a instrument rated pilot and a drone pilot (UOC licensed). CASA is about to bring in some new laws for drones in Australia which will not only endanger pilots, but the general public as well. Check out his video, it explains it really well.

That should have come with a rant warning!

Yet again another person trying to promote their own self interest without any substantial evidence, nor knowledge of physics. The new regulations are for sub 2kg drone and he demonstrates with a 2.8 kg drone. The most popular drone (DJI Phantom) actually weighs in at around 1.2kg, so less than half the weight of the drone pictured. Drones are made of very breakable material, they virtually explode on impact, even in a very low speed collision.

 

While the risk of a drone colliding with an aircraft is not insignificant, the risk of it bringing down a commercial aircraft is miniscule to nonexistent!!

 

The new rules proposed by CASA are the most sensible piece of legislation that CASA have ever imposed on the general public. With regard to those who will flout the new laws, they will do so regardless of what the laws say at the time. The only thing I would have like to have seen added would have been shielded operations for operations within 3nm of airports/helipads.

 

 

  • 1 year later...
Posted

Their is a lot of hysteria about drones on ch 7 there was a program The battle for Mosul where they claimed quads were dropping bombs on people. The producers clearly had no idea about the the subject they showed a dji phantom with a 'steel bomb it could never lift. Not to mention how difficult it would be to know when you are over the target.

 

 

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Posted
Their is a lot of hysteria about drones on ch 7 there was a program The battle for Mosul where they claimed quads were dropping bombs on people. The producers clearly had no idea about the the subject they showed a dji phantom with a 'steel bomb it could never lift. Not to mention how difficult it would be to know when you are over the target.

Media Rule #1: Never let facts spoil a good story.

 

Media Rule #2: See Rule #1

 

 

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Posted

I've just completed my CASA drone survey. The summary I gave was they they should use a measured risk assessment and management approach, without looking at what others have done (and made a mess of).

 

 

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  • 2 weeks later...
Posted
Simple fix all drones sold to carry GPS and limited by GPS to 300ft. Many ways to fix the problem for over the counter toys, but it has to be done now or they cant be imported or they become illegal. Why do we need a plane to crash first to stop what WILL happen.

It's not hard to hack firmware. Most of the drones already have those features.

 

 

Posted
It's not hard to hack firmware. Most of the drones already have those features.

That was also a comment I made to the CASA survey, which was that human ingenuity will inevitably overcome many engineered solutions. The original post highlights the problem we have currently with the media, i.e. people without the necessary technical knowledge or experience in the subject matter making generalized comments.

 

 

Posted

Jus

 

That was also a comment I made to the CASA survey, which was that human ingenuity will inevitably overcome many engineered solutions. The original post highlights the problem we have currently with the media, i.e. people without the necessary technical knowledge or experience in the subject matter making generalized comments.

Just as an aside. . . .

 

A bloke I know ( nothing to do with flying nor drones ) told me that he had one fly very low over his family barbecue party last Saturday. ( !9th August )

 

It circled his garden, he could not estimate how high t was, as he had no knowledge of flights and heights. . . .His mates 'Geed him up into getting out his high power comptetition .22 air rifle and having a pot shot at it, which he apparently did.. .

 

Whether his pellet caused it to crash, is not known, but, when it then circled and then hovered above his garden, he took another shot at it and apparently hit the drone camera. . . .it spun around and crashed into the trees across the road from his house and he showed me the 'Trophy' wreckage. No one has claimed it thus far, and he has decided to keep it. . . .Unless he hears from the owner and does a deal. He hit the camera lens and screwed that up completely, which was probably why the owner lost it., he found Two .22 pellets, one in the cam lens, and one in the control circuitry so this would explain why the thing descended over his garden and was lost to the owner, as these units normally have a 'Return to base 'function when things go awry.

 

I dunno who was in the wrong here,. . .the Drone owner for fecking about spying on a private party, or Him, for having an over powered air rifle. . . .there's one fir the legal eagles innit ?. . .

 

This was a very expensive looking machine, with five rotors and a diameter of around five feet OH. Sorry,. . .150 cm. . . .

 

 

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