On Fri, 6 Nov 2015 22:27:54 -0500, Jerry Sauk wrote:

Mr. Luddite wrote:
On 11/5/2015 7:38 PM, Jerry Sauk wrote:
Mr. Luddite wrote:
On 11/5/2015 1:30 AM, wrote:
On Wed, 04 Nov 2015 18:18:20 -0500, John H.
wrote:

On Wed, 04 Nov 2015 15:56:06 -0500, wrote:

On Wed, 04 Nov 2015 14:45:37 -0500, John H.
wrote:

On Tue, 3 Nov 2015 17:01:24 -0500, Keyser Söze
wrote:

...eagle takes down annoying drone:

https://www.youtube.com/watch?v=Hr-xBtVU4lg

Hope this happens everywhere...



No you don't, dumb****. What happened to the eagle (if that's what
it was). Those
propellers will easily take off a finger, let alone cut up an
eagle, or hawk or any
other bird, very badly. You'll note the drone is still
transmitting, which means the
owner can easily retrieve and repair it.

No one knows what happened to the bird. I hope it made it.

And I hope you learned something.

Myth busters tested drones. All but the biggest were pretty much
harmless. Some of the big commercial ones with carbon fiber
blades can
leave a mark ;-)

I've seen the damage a plastic airplane propeller going at a much
slower rpm can do
to a leather covered ottoman corner. Ate right through it to the
stuffing. My wife
was very unhappy. I'm thinking your 'myth busters' test is bull****.
Although small
and plastic, those props are going several thousand rpm, and they're
very sharp.

Here's a view of some of the damage caused with the airplane/drone
that caused the
problem, in some cases. It's in French, but you get the idea.
Imagine if those cuts
were in an eagle's neck? Or a foot joint?

http://chrismeme11.over-blog.com/article-36258812.html

Dunno. They were using a few different small hobby drones hitting a
ballistic gel dummy and watching it on a high speed camera.

This really comes down to this being a very light propeller driven by
a pretty weak motor. You can't compare that to the old 2 stroke model
airplanes.



Based on what I've read (and heard), the lithium/ion batteries used
in these hobbyist quads are more dangerous than the spinning
propellers.


Many are the lighter Lithium Polymer now which is supposed to be safer.

Supposed to be but lithium is lithium and it reacts violently to water
vapor ... just the humidity in the air can set it off. The safety
factor is in the packaging it's contained in. If it is compromised,
you have a problem.

I visited a lithium battery manufacturing plant once. The assembly
was done in a clean room where the humidity was maintained at 5
percent or less. As we were putting on our "monkey" suits in the lock
before entering the guy I was with warned me about how hard it would
be to breath when we entered the clean room. He wasn't kidding. When
we entered I gasped for air at first. 5 percent humidity is extremely
uncomfortable.




Interesting. The humidity in an airplane at altitude is also very low
and every seat has at least one lithium battery in their possession. I
wonder who, if anyone, regulates the packaging. Some lithium batteries
I have seen are in a very soft-sided package - almost like a ketchup
packet.

All of my lithium polymer batteries are 'soft sided'. They can expand and contract,
but they're a bit stronger than a ketchup packet. I've had one expand quite a bit
when severely discharged. Luckily I was able to salvage it following a tip in a
forum.
--

Ban idiots, not guns!