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-   -   Drone delays Westpac helicopter rescue (https://www.pprune.org/rotorheads/613976-drone-delays-westpac-helicopter-rescue.html)

layman 3rd Oct 2018 07:19

Drone delays Westpac helicopter rescue
 
Had a quick search and didn't find this posted elsewhere

Drone delays air rescue of fisherman stranded on rocks in Gold Coast Seaway - ABC News (Australian Broadcasting Corporation)

"Helicopter rescuers have had to wait for a drone to leave the skies above a boat accident before an injured fisherman could be winched to safety on the Gold Coast."

"CASA spokesman … [said] … "This is an absolute textbook example of what not to do with your drone"

"The pilot of the drone involved has not been found."

Hopefully he(?) will post on social media enabling police / CASA to go after them

I wonder if it would be possible for rescue (and?) aircraft to be fitted with short-range jammers/disrupters to diminish the chance of this sort of thing happening in the future?

Bell_ringer 3rd Oct 2018 07:57

The downwash would be sufficient to put it into the drink, provided they can keep it visual on the way.

chopjock 3rd Oct 2018 09:09

It was not the drone that delayed the rescue, it was the helo crew. Would the crew have delayed the rescue if a seagull was seen in the area? It could be the drone operator saw the helicopter had landed so didn't need to back off yet. Could be the drone operator was waiting for the helo to lift and would then know it's time to buzz off...

havick 3rd Oct 2018 12:27


Originally Posted by chopjock (Post 10264743)
It was not the drone that delayed the rescue, it was the helo crew. Would the crew have delayed the rescue if a seagull was seen in the area? It could be the drone operator saw the helicopter had landed so didn't need to back off yet. Could be the drone operator was waiting for the helo to lift and would then know it's time to buzz off...

please...... you’re kidding right?

chopjock 3rd Oct 2018 12:58


please...... you’re kidding right?
It makes me concerned when a rescuer would let someone risk death because they "saw a drone". Particularly if they can still see where the drone is.

GrayHorizonsHeli 3rd Oct 2018 13:10

I love drone videos


chopjock 3rd Oct 2018 13:51

Here's another...

http://www.facebook.com/thehelicopte...6162750406696/

aa777888 3rd Oct 2018 19:01

Not so different from a bird strike. Actually, I'd be much happier hitting a 1 lb DJI drone made out of plastic vs. a nice, solid, 8 lb Canada goose. Actually, I'd be much happier hitting nothing, but you know what I mean!


casper64 3rd Oct 2018 19:31


Originally Posted by aa777888 (Post 10265170)
Not so different from a bird strike. Actually, I'd be much happier hitting a 1 lb DJI drone made out of plastic vs. a nice, solid, 8 lb Canada goose. Actually, I'd be much happier hitting nothing, but you know what I mean!

https://www.youtube.com/watch?v=YPzrnbr7snE

And there, you are completely wrong! An 8lb Canada goose is big and heavy, but made up of feathers, blood, fat, intestines and a little bit of bones…Yes, it will make a huge mess, might end up on your lap, hell might even knock you out for a little bit but that's about it, unless you are very, very unlucky.
The battery and engines of a DJI (or any other drone) is made of very high dense material that won't bulge or splatter when it hits the first layer of protection (your windscreen)… but will penetrate right trough and hit you, let's say, in the face. Imagine that happening with, say, 100kts.... the battery will probably end up somewhere in the back end of your skull…….

If it hits a critical part of the helicopter… same story. A bird will be sliced to pieces and do some Damage. A part like the battery will most likely destroy the part of the helicopter it hits.

The video damage you show is of a fixed wing, that was most likely travelling about twice or three times the speed of a helicopter if not more...

Regards,
Raymond

krypton_john 3rd Oct 2018 19:51

Goose into a MRB seems like it would be a catastrophe - - I'd be very interested to know what would happen if a drone hit one. .

aa777888 4th Oct 2018 02:15


Originally Posted by casper64 (Post 10265192)
And there, you are completely wrong!
...
The video damage you show is of a fixed wing, that was most likely travelling about twice or three times the speed of a helicopter if not more...

I'm not so sure I'm completely wrong. The first video of the drone shown above was at 238MPH, according to this link:

https://www.udayton.edu/blogs/udri/1...in-the-sky.php

So the two videos are roughly comparable if we assume the Cessna in video I posted was doing a typical Cessna Conquest speed.

However, I will agree that your argument about the density/compressibility of a typical LiIon battery has some merit. It would be interesting to see a more definitive study of the relative dangers of greater mass vs. higher density vs windscreens, rotor blades, etc.

GrayHorizonsHeli 4th Oct 2018 03:29

Regarding a goose hitting MRBs and being a catastrophe, heres my story...

the pilot of an AS350 was setting seismic bags. Noticed something catch his eye. Glanced up to see a ruffled grouse on short final for his rotor disk.
uneventful return to staging area where the carcass was removed from the cooling air inlet and some stringy gut materials peeled off the roof and trans cowl. Some morbid streaks on the blades worthy of a B rated horror flick.

back to drones...

if this fisherman wasnt critical, there was no rush to pick him up. Why fly with the potential hazard if that was the case?

[email protected] 4th Oct 2018 06:11


The video damage you show is of a fixed wing, that was most likely travelling about twice or three times the speed of a helicopter if not more...
and the tip speed of an average helicopter will be in the region of 400kts - in the hover - add in a cruise speed of 100 kts and the impact speed (on the advancing side) could easily be 5 -600 kts.

GrayHorizonsHeli 4th Oct 2018 13:38

and the damage sustained on that MRB at the tip will be dependant on the type and contruction. Which varies drastically.

Non-PC Plod 4th Oct 2018 15:45


Originally Posted by krypton_john (Post 10265210)
Goose into a MRB seems like it would be a catastrophe - - I'd be very interested to know what would happen if a drone hit one. .

I would also like to know what would happen if a drone hit a goose!

krypton_john 4th Oct 2018 21:01


Originally Posted by Non-PC Plod (Post 10265921)
I would also like to know what would happen if a drone hit a goose!

Sounds like a fun project - should see if I can get some funding... maybe if I phrase the application along the lines of "impact of gender neutrality in modern context of drone - goose interaction" or such like.

[email protected] 4th Oct 2018 21:51


and the damage sustained on that MRB at the tip will be dependant on the type and contruction. Which varies drastically.
at 500kts, I think the result will be the same, regardless of construction

GrayHorizonsHeli 4th Oct 2018 23:42

I disagree.
lets compare R22 and 214....and go.

[email protected] 5th Oct 2018 06:07

You go and fly them both into a drone and let us know how you get on #fascilecomparisons

You might be able to cut through small trees with the big Bell blades but, as already discussed, a lithium battery at 500 kts is going to be very different - but do feel free to try....

duke996 5th Oct 2018 08:15

Hi guys,

For the record, I was the pilot for this and thought I would clarify a few things. We landed about fifty metres away on the rock wall to access the situation as all we were told over the radio was that a boat was being smashed on the rocks with an elderly gentlemen on board. He was unable to be moved by local surfers and rescue jet skiers due to both the waves on the rocks and his bad hip (hip replacement and the fact he was 78 years old). Our rescue crew was able to climb over rocks onto the boat and secure him in a rescue harness on the bow whilst myself and the aircrew waited for his radio call to let us know he was ready for a winch retrieval back into the chopper then to an ambulance (he had deep lacerations on his legs as well). Anyway, whilst we were on the ground waiting for the call with blades still turning, a drone was sighted above us approximately 20 metres ahead. It continued flying around us videoing as close as ten metres from the disc. We had to wait another five minutes for it to leave and I actually filmed it above us on my personal phone. It did hinder our operational response time and we were lucky the patient was secure with our crew and we were told the boat was fairly stable on the rocks at the time. If anyone here thinks I should have risked the crew, myself and the rescue boats and jetskis in the vicinity by becoming airborne whilst it flew within ten metres of our disc, then thats their opinion. Personally, I don't want to be the test pilot hitting a drone to see what happens, regardless of size and weight. I have already had a near miss with a phantom at 100 knots that passed under the rotor disc. The drone pilot who has yet to be identified has contacted the media to let them know he has 'awesome footage' of us sitting on the wall waiting to do the rescue. I will let the authorities that are 'very interested' in chasing that one up! I also refuse to get in a slinging match with drones vs helo's so don't bother if thats what you see here. I just thought people should know a few more of the facts about this job.

Regards,

Luke O'More (duke 996)

John Eacott 5th Oct 2018 10:27

Good call, Luke; well done :ok:

[email protected] 5th Oct 2018 10:38

Good job Luke, plenty here don't understand the process of SAR.:ok:

However, you have made the error of introducing facts into the speculation which won't impress some posters...........

GrayHorizonsHeli 5th Oct 2018 13:08

wanna talk about those batteries?


sure, they're a subject mass and the energy transfer would do some damage, but hardly catastophic. they aren't solid by any means. Most lithium batteries aren't.
and they only weigh under 500grams.

[email protected] 5th Oct 2018 15:35

Get someone to throw one at your head and then tell me they aren't solid..............................

Back of a fag packet calculation would give Kinetic Energy of a 500g battery at 500kts (257 m/s) as 16,500 Joules - still think that won't hurt a Bell blade?

abgd 5th Oct 2018 18:49

Out of curiosity, are birdstrikes whilst maneuvering slowly or hovering in a helicopter common?

I can understand how a bird and a 150kt aircraft may meet before the bird has had time to get out of the way, but am guessing a goose or swan or for that matter a blue-tit will keep out of the way of a hovering helicopter? I suspect that in this mode of flight a drone is far likely to collide if they're anywhere near each other (i.e. filming or assisting at the same event).

PPRuNeUser0211 6th Oct 2018 08:48


However, I will agree that your argument about the density/compressibility of a typical LiIon battery has some merit. It would be interesting to see a more definitive study of the relative dangers of greater mass vs. higher density vs windscreens, rotor blades, etc.
Already done, the publicly released report is below. I don't think it has all the details in of comparison to birds but the results are fairly straightforward.

https://www.gov.uk/government/publications/drones-and-manned-aircraft-collisions-test-results

Non-birdstrike Certified Helicopter Windscreens
5.2 The non-birdstrike certified helicopter windscreen proved to have a low resistance to
all the classes of drones tested, with penetration through the windscreen shown to
occur at speeds well below the normal cruising speed of a helicopter of that type. For
the fixed-wing drone, which is itself capable of a significant speed in flight, it was
found that the drone could penetrate a helicopter windscreen of this type even if the
helicopter was stationary.
5.3 As general aviation (GA) aircraft do not have a requirement for birdstrike certification,
the result from the non-birdstrike certified helicopter could be read across to GA
aircraft with comparative severity in the result of a collision.
Birdstrike Certified Helicopter Windscreens
5.4 The birdstrike certified helicopter windscreen was found to be much more resistant,
but it was found that the quadcopter drones could penetrate these windscreens when
the closing speed was similar to the helicopter’s typical cruising speed. The speed
the fixed-wing drone can itself reach meant that it could penetrate the windscreen if
the helicopter was moving at a speed significantly below the normal cruising speed.
When the helicopter was stationary, however, it was shown that a fixed-wing drone,
when flying at its maximum speed, was unlikely to penetrate this windscreen.
Helicopter Tail Rotors
5.5 The modelling of helicopter tail rotors showed that they would be vulnerable to
impacts with all types of drones. Due to the very high speed of a rotating tail rotor
blade, it could be critically damaged by an impact with any drone.
5.6 Again, it should be noted that although the most accurate properties available were
used, the helicopter tail rotor results were based on modelling only, with no live
testing to calibrate the model.

[email protected] 6th Oct 2018 09:35


Out of curiosity, are birdstrikes whilst maneuvering slowly or hovering in a helicopter common?
I have had a couple in the past but that was operating on an estuary where the sea bird concentration was quite high. One seagull flew down through the disc as we approaching dispersal which was rather terminal for the gull but only left smears of blood and feathers on the blade.

Some of the worst are the big soaring birds which tend to be less easy to see as they can be almost stationary and then suddenly get very big in the windscreen - there are plenty of stories about them ending up in the cockpit, some still alive and quite pi**ed off.

Fareastdriver 6th Oct 2018 10:37

Two of my innumerable birds strikes of note.

Germany, mid seventies, low level over Germany. A flock of starling or sparrows erupt from some trees and I go IFR in birds. Lots of banging and crashing so I decide to proceed to the nearest RAFG airfield to, if nothing else, clean the blood off the windscreens.

The base is a Harrier base and as soon as I told them I had had a birdstrike they went into full emergency mode because it was a Harrier base and apparently they are allergic to birds. On shutdown I had a lot of important people surveying the damage. I took the most important up to the top deck, opened the intake and pointed out the mass of feathers and bits attached to intake struts and compressor with the normal statement that the Turmo IIIC merely converts birds to fuel. Meanwhile my crewman was levering out carcasses from the rotor head assembly.

We washed the windscreens, fired it up and punched off back to base.

The other was in China where I ran into a cormorant flying illegal IFR at 2.500 metres. It collected the radar radome and dented in so badly that it jammed the scanner which was quite inconvenient because I was dodging cu-nimbs at the time. However we survived and landed safely.

The cost of a new radome was horrendous and would have taken a couple of days to arrive.

The local car repair shop had it as new in an afternoon.

nonsense 6th Oct 2018 12:45

As a student engineer I was told a (probably apocryphal) story about British Rail borrowing a "chicken cannon" normally used to test jet engines, to test the windshield of a high speed train. A chook was shot at the train, and not only penetrated the windshield, but the rear wall of the driver's cabin, doing quite a bit of damage to the machinery behind.

Upon discussing this unexpected result with the supplier of the cannon, the famous words were uttered:

"You did thaw the chicken, didn't you??"

Mass alone, momentum (mass x velocity), and even kinetic energy (1/2mv^2), is not the whole story; hardness is very relevant.

GrayHorizonsHeli 6th Oct 2018 12:58


Originally Posted by [email protected] (Post 10266728)
Get someone to throw one at your head and then tell me they aren't solid..............................

Back of a fag packet calculation would give Kinetic Energy of a 500g battery at 500kts (257 m/s) as 16,500 Joules - still think that won't hurt a Bell blade?



Not as much as you think it would. I'm not denying damage, i'm disputing catastrophic damage. practice your reading comprehension

[email protected] 6th Oct 2018 16:42


I'm not denying damage, i'm disputing catastrophic damage.
No, you are just splitting hairs for the sake of it.

havick 6th Oct 2018 17:53


Originally Posted by GrayHorizonsHeli (Post 10267339)
Not as much as you think it would. I'm not denying damage, i'm disputing catastrophic damage. practice your reading comprehension

either way would still ground a helicopter for inspections.

ShyTorque 6th Oct 2018 19:03

I've known birds come through the windscreen and hit the front seat occupants in the upper body/head, causing injuries. If a drone did so, and hard parts hit the pilot in the face, I doubt he would survive.

I've also known birds come through and hit the engine levers, shutting down the engines.
I've also had a sea eagle take great objection to the helicopter I was hovering in "his" territory (SAR training with a winchman out on the cable) and he circled us a few times before attempting to attack us and almost flew through the disc. Those birds are very big..... so we cleared off! It wouldn't have been so easy if it had been a real rescue.

Seagulls don't seem to see helicopters as a threat to themselves. They don't have airborne predators and if you watch a large flock of them they often bump into each other in flight. I've had a few fly lazily into the rotor disc over the years, they made no effort to avoid us.

During a rescue there is enough to concentrate on without having to worry about some idiot flying a drone in close proximity.

212man 6th Oct 2018 21:31


They don't have airborne predators and if you watch a large flock of them they often bump into each other in flight.
i think that’s true of most large birds. Buzzards/vultures seemed totally oblivious to us - almost like they can’t see us and their brain says “computer says no”. Took out two while hover taxiing to land. First one exploded (a 212 blade will do that), buddy was amputated at the wing root and catapulted into a storm ditch. It appeared a few minutes later, hopping around looking very unhappy.

[email protected] 7th Oct 2018 08:35


Mass alone, momentum (mass x velocity), and even kinetic energy (1/2mv^2), is not the whole story; hardness is very relevant.
I guess that would depend on whether you were simply considering impact damage/penetration or shock loading to rotating components as well.

abgd 7th Oct 2018 10:19

Thanks, I had expected birds would be more sensible. Seems I was wrong.

GrayHorizonsHeli 7th Oct 2018 20:27

Crab, Here I thought you were splitting hairs commenting on a big bell blade cutting trees yet being so disturbed structurally hitting a meagre 500g multi packed lithium battery encased in plastic.
Lemme take my camping hatchet to the tree and then the battery and see which one takes more force to get thru.

[email protected] 7th Oct 2018 21:40


Crab, Here I thought you were splitting hairs commenting on a big bell blade cutting trees yet being so disturbed structurally hitting a meagre 500g multi packed lithium battery encased in plastic.
Lemme take my camping hatchet to the tree and then the battery and see which one takes more force to get thru.
Que? I haven't a clue what you mean by that! What relevance does a camping hatchet have to this thread???

GrayHorizonsHeli 8th Oct 2018 01:04

As in hardness. Do you read anyones post?

John Eacott 8th Oct 2018 05:45

Interesting comparison of birdstrike vs drone strike:
https://www.ainonline.com/aviation-n...airplane-wing#


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