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narfi

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You get them often, it's just that you call them hurricanes, and there is no physical difference between them, or the 3rd name used for the same storm: cyclones, as we say in Australia.
To get pedantic, he was right..... :p
By definition you will have cyclones in Australia and we will have hurricanes in the US.....


In the North Atlantic, central North Pacific, and eastern North Pacific, the term hurricane is used. The same type of disturbance in the Northwest Pacific is called a typhoon. Meanwhile, in the South Pacific and Indian Ocean, the generic term tropical cyclone is used, regardless of the strength of the wind associated with the weather system.
(I'm no meteorologist, I just google stuff)
 

pictsidhe

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I once had a tornado come over me so low that I could smell it. I wasn't very happy about that as I was standing on a partially built roof.
 

MaydayMayday

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Can someone please explain the rain induced nose drop on canard aircraft?

What is a Sparrow Strainer and why is it added to a canard elevator and not to other aircraft types? Is the Sparow Strainer the large device attached to the trailing edge of the left canard on Proteus? Is the one on Proteus movable like a trim tab?

Also, what happens to a canard when it flies through a bunch of bugs? Would not vortex generators on the wing and canard reduce the issue of disrupted airflow due to surface contamination?
 

Hephaestus

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Can someone please explain the rain induced nose drop on canard aircraft?

What is a Sparrow Strainer and why is it added to a canard elevator and not to other aircraft types? Is the Sparow Strainer the large device attached to the trailing edge of the left canard on Proteus? Is the one on Proteus movable like a trim tab?

Also, what happens to a canard when it flies through a bunch of bugs? Would not vortex generators on the wing and canard reduce the issue of disrupted airflow due to surface contamination?
Nose drop - the airfoil looses lift with contamination, get bugs or water drops - you loose lift, therefore you need more up elevator to maintain. VG strips can help with this, but you still loose some.

Sparrow strainer is a patch used most often on the quickies to give a neutral elevator trim. You can fly without, it's apparently a bear, you're using your arm to hold the elevator down the whole time with little/no feel otherwise.
 

BBerson

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Probably use a turbulator tape strip (not VG ) for eliminating laminar trim issues in rain.
The VG might increase the canard stall angle which is not wanted.
 

wsimpso1

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Saline Michigan
Can someone please explain the rain induced nose drop on canard aircraft?

What is a Sparrow Strainer and why is it added to a canard elevator and not to other aircraft types? Is the Sparow Strainer the large device attached to the trailing edge of the left canard on Proteus? Is the one on Proteus movable like a trim tab?

Also, what happens to a canard when it flies through a bunch of bugs? Would not vortex generators on the wing and canard reduce the issue of disrupted airflow due to surface contamination?
Sparrow strainer was covered rather thoroughly above, including pictures. Page back and look.

Summarizing on contaminated canards. Original canards would trip the boundary layer pretty easily with things like drops and bug exoskeletons, and stagnation point would move, which then shifts the Cl vs alpha curve. Required an increase in delta and alpha. The solution was a new laminar flow airfoil by John Roncz that did not shift its Cl vs alpha curve, so while the airplane might have a touch more drag with contaminated foils, it would still fly well that way. John's new foil included an elevator shape that was pretty close to zero Cm about its hinge line, so it also did not need a sparrow strainer - just nominal balance springs adjustable for trim. It had one other benefit - span and thus wetted area were reduced with the new foil. John Roncz pulled off a win-win-win for Burt...

Billski
 
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Scheny

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Vienna, Austria
For those people who think that contamination is a myth:

I once flew a DA42 (first gen with smaller Thielert) between spring and summer, when I encountered a heavy storms in FL70 and above. First adventure was, that climb suddenly increased to 2650fpm at economy settings, followed by sinking at 1500fpm at max emergency power...

During approach to Linz (Austria), I heard a 737 and an A320 divert and got nervous (they have weather radar, I got a Stormscope only). The wings accumulated a small wedge of 1/3 inch of slush at the tip (barely noticeable) with the remainder looking perfectly fine.

In the end I needed 85% thrust just to maintain altitude at best endurance speed!!! Normally it would do that on less than 50%. In case you don't know, the aircraft has TKS anti-icing (glycol) and it was running on full speed! Luckily it was hot below the storm and the ice melted away within minutes while in approach.



This aircraft is not very susceptible to contamination. I heard stories of gliders who barely make it back when the first drops strike the wing.
 

pictsidhe

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There has to be a good chance his stick forces are wrong at TO speed. I seriously doubt he calculated or tweaked the control
design for them.
Now he is trying to fly it, he is finding out that "I can fix that later" may not have been such a wise strategy.
 

hammer

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Sep 6, 2020
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7
I had a look at the new video - looks like 30s acceleration to 90kts - jetguy should be able to give us a reasonably accurate HP value from this.
 
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