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mad_jock
23rd Feb 2014, 05:57
Epic bird crashes threw planes windshield - YouTube

Can't remember seeing this before on here.

Pace
23rd Feb 2014, 08:11
MJ

Interesting clip but strange? Not saying its not genuine but what happened to the prop taking such a big bird through it? It came through the screen but no wind sound or vibration sound changes!
The amount of drag having a sizeable hole in the screen and the amount of wind in the cockpit yet the pilots cap does not move at all even when he looks right placing the peak of his cap across the hole.
Maybe genuine but odd to say the least.

Pace

mad_jock
23rd Feb 2014, 08:31
I have had them go through the prop and appear out the other side unsplattered and that was a 4 blade job, well it appeared to go through it

Also they can come in round the prop.

As for the cap ?

Would have thought because of the pressure increase inside the hull alot of the wind will get put over the top.

I got made to open our DV window below 140knts by a TRE and there was remarkably little wind blast.

Pace
23rd Feb 2014, 09:01
Having never had a Big Bird dive through the screen (or small one) I would not know :E but nevertheless I was surprised at the lack of change of sound or lack of air movement not even the second pilots very short hair moved yet there was a lot of activity with what looks like material (or bits of bird) flapping around near the roof over the screen.

I have wondered what the effects would be like loosing a complete screen with the huge level of increased drag such an event would create

Pace

mad_jock
23rd Feb 2014, 09:15
Its weird that one it depends if there is a hole right through to the back or not so the wind can get through.

A pressure bubble will form up and act like there is a window there, you can see the label off the belts flapping about a bit.

To be honest I have always been amazed how the yanks keep those hats on. We used to watch them play golf in Aberdeen on the links and they always had them on and didn't struggle. Pair of DC clamping them on as well probably helps?

Andy_P
23rd Feb 2014, 09:35
FWIW, the audio sounds like a gopro with the waterproof back on, so if you are listening for air noise I think you will be disappointed..

Pace
23rd Feb 2014, 10:20
MJ

The screen is part of the airflow profiling of the aircraft shape! Remove the screen and not only would the airflow change over the tail causing handling problems but the very fact that there is no way out for the air would cause massive drag!
Probably best way to look at it is dragging a bucket through water ( a lot of drag ) cut the bottom out of the backet and there would now be minimal drag!

I know I have lost two expensive Boss caps at sea on diving expeditions so they do blow off easily if the wind gets under the rim although I know there are ways of attaching them!

Not saying the film is not genuine and understand the point re sound recording on the Go Pro just surprised as the hole looks fairly large upfront

Pace

mad_jock
23rd Feb 2014, 10:43
I know what you mean, but when I opened the DV window it wasn;t a howling gale at 140knts.

And the difference between a bucket and a flat plate is pretty much negligible when put through water. BUt its slightly different because water is incompressible.

The air molecules will go to the area of least pressure which will be over the roof and round the sides when the cabin becomes pressurised with the dynamic air flow.

If the rear window popped out the pressure would then drop and there would be more flow through the cabin and more drag.

But I stand to be corrected.

maxred
23rd Feb 2014, 10:47
Looking at the video a couple of times I think its only part of the goose that went through the windshield after being chopped up by the prop. If the full bird had gone through in one piece it would have been sat on the rear shelf or worse continued into the rear fuselage.

And possibly taking the pilots head with it. I actually saw this on a US thread initially, and the debate assumed it was all genuine. It looks genuine IMO. It does appear to be only part of the bird that ends up inside, but lots of blood and goo splattered on the side window:sad:

mad_jock
23rd Feb 2014, 10:53
the goo goes everywhere.

And it really stinks.

If you do another 4 sectors or the plane sits for a couple of days waiting for a ginger to turn up to inspect it and it then drys on the engineers love trying to get it off.

Pace
23rd Feb 2014, 12:37
MadJock

If the Nose baggage compartment comes open on certain aircraft they can become almost un flyable.

While air and water are different we all know what happens when we stick your example of a plate (air brakes ) into the slip stream.

i am not an aerodynamic expert but know even a small change like Piper made fitting Lopresti air intakes improved cooling and speed to some of their aircraft namely the Seneca and Saratoga.

Aircraft designers spend ages in wind tunnels studying how one curve effects the airflow over another and then onto and over control surfaces.

The loss of a complete screen would in my guess create massive drag as well as disruption of airflow over vital control surfaces making the aircraft almost impossible to fly.

I do not know if there have been instances of complete screen loss or the effects of that screen loss

But I stand to be corrected too :ok:

mad_jock
23rd Feb 2014, 13:00
I am not saying there won't be drag but the reason why you won't see as much air movement inside is because they are in a high pressure relatively static bubble of air.


Most drag that comes off airbrakes is created by the back surface the blade creates turbulent flow and that gets rid of energy. In this case the back of the aircraft retains its shape so not as much drag as you might expect would occur.

this old thing

http://img209.imageshack.us/img209/4601/sphereairfoilcomparison.jpg

http://staff.civil.uq.edu.au/h.chanson/pictures/foil04.jpg

And this flw is from right to left and you can see the stagnation line in the middle.

If they had baggage bay door and it had popped open I don't think they would have survived to be honest the tunnelling of the cabin of the air would have made changing attitude quite hard.

abgd
24th Feb 2014, 00:00
OK... say yoou're doing 120 knots at 2400 rpm (just for some plausible figures) that makes about 60 metres per second with blades sweeping every 50 cm (40 revs per second & 3 blades).

Plausible if not probable that the prop will strike the neck or tail of the goose, without in all probability making a huge fuss about it.

Background Noise
24th Feb 2014, 08:59
They do get through the prop - even on a high performance prop. There is still more space between the blades than there is blade ie there is more gap than blade.

This was the RNHF Sea Fury at Margate in 2006:

http://www.royalnavyhistoricflight.org.uk/news%20images/Dent.jpg

abgd
24th Feb 2014, 09:36
And wasn't there a parachutist who fell unscathed through a helicopter rotor a while back?

mad_jock
24th Feb 2014, 09:45
Was his name lucky?

maxred
24th Feb 2014, 18:48
For the doubters, here's another hot off the press


Caught on Cam: Plane window breaks in mid-flight - ABC-7.com WZVN News for Fort Myers, Cape Coral & Naples, Florida (http://www.abc-7.com/story/24795525/caught-on-cam-plane-window-breaks-in-mid-flight#.UwlNYn-9KK0)

daxwax
24th Feb 2014, 22:13
I'm sorry about Goose. (Sniff). Everyone liked him. (Sniff). I'm sorry.







Hat
Coat
Taxi for 1

Heebicka
26th Feb 2014, 10:39
...that angry birds t shirt... lol :)


https://i.chzbgr.com/maxW500/8080922112/h856771CF/