The 2021 Aviation thread

Swaying

New member
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DC, USA
Good video, on the greatest hits rotation at every safety standdown. 

For a flyover at an NFL game, there's decent chance flight lead was someone fairly senior. Flights like that can be the kind of thing where a senior guy who doesn't get to fly much any more says, "yeah, put me on that one." 

 
The old guys in my neighborhood scratch built a JN4D Curtiss Jenny.  It flew this summer.  There is a video of that on face book but I refuse to join that.  Here is a video from a year ago.




 

Winston29

Member
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SF Bay Area
Being a huge fan of helicopters, this was a fun day in early 2007.  

A powerful storm had knocked down some high-tension towers in Redwood City the night before.  

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Two copters.jpg

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Rain Man

Super Anarchist
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Wet coast.
chum said:
I thought it was posted last year? Ive been watching it. Looking at the picture, they must have some kind of synthetic display forward, how can he see the runway (along with everything else out front)? I may have missed the reference.

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Apparently it has a laminar flow wing.  How will they keep the bugs off?

https://www.researchgate.net/publication/261100623_Impact_of_Insect_Contamination_on_Operational_and_Economic_Effectiveness_of_Aircraft_with_Natural_Laminar_Flow_Technology

 

Zonker

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Looking at the fuselage it's also a laminar flow shape. Gliders are very fussy about laminar flow.

They have wipers that clean off the wings in flight. I think in perfect condition it could work. But maybe not every day.

I think rain fucks up laminar flow on wings.

 

chester

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Looking at the fuselage it's also a laminar flow shape. Gliders are very fussy about laminar flow.

They have wipers that clean off the wings in flight. I think in perfect condition it could work. But maybe not every day.

I think rain fucks up laminar flow on wings.
isn't laminar flow the goal for any shape that moves through air or water for that matter?  isn't the opposote of laminar flow turbulence? 

 
Looking at the fuselage it's also a laminar flow shape. Gliders are very fussy about laminar flow.

They have wipers that clean off the wings in flight. I think in perfect condition it could work. But maybe not every day.

I think rain fucks up laminar flow on wings.


Doesn't their weight throw off the gliders stability when they go out on the wing to wipe it?


My former SGS 1-35 had a metal wing.  It was laminar enough.  I think the airplane in question would mostly be flying above bug altitude, but on the way up it would collect some.

Rain definitely messes with glider wings - higher stall speeds and more drag.  That would probably be the bigger problem in an airplane that is meant to travel, which implies flying in weather.

 

Zonker

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isn't laminar flow the goal for any shape that moves through air or water for that matter?  isn't the opposote of laminar flow turbulence? 
Let's put it this way - it's a nice goal. IF you have a dry sailed race boat you can probably keep laminar flow over the keel, rudder and most of the bulb. Hulls are too long and it will trip before it gets too far. (Depends on boat speed)

If there is not too much plankton in the water (seriously, it trips the flow) you can stay laminar.

A typical rough antifouling paint surface that isn't sanded to 400 grit won't be laminar, thus no point in using laminar flow sections on cruising boat appendages.

 

Rasputin22

Rasputin22
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I have a small single place sailplane with a laminar flow wing. I do notice the adverse effects of even light rain such as when I fly into Virga, the light rain that originates at altitude when a thunder head anvil cloud just sort of wrings itself out. The cloud disappears and you can see a falling column of rain falling,





     Far worse for ruining laminar flow on a sailplane wing is bugs and grass that gets kicked up by the towplane propwash and deposited on the leading edges of those long skinny wings. Once launched bugs aren't really a problem at altitude. The fancy 'wing wipers' seen above are usually activated once the tow rope in released and then stowed it little recesses in the wing root. Pretty pricey option only on top end craft. My simple little 13.5 meter plane does not have such amenities. 

    One April Fools Day when I was a student sailplane pilot, I brought a roll of toilet paper with me and waited until I had rolled my plane out to the launch queue to await my towplane launch. There is usually a few club members hanging around the launch area so I made sure everyone saw me pull out a hand sprayer from the gold cart and carefully mist just a light spray of water on the leading edges of my wings, rudder and elevator. They all thought I was going to do a final clean and wipe my wings off and an old timer told me not to bother because on the takeoff roll the grass, dirt and bugs would just get back on the wings. I told them to wait for it... and then grabbed the roll of toilet paper and carefully centered the paper on the leading edges and then rolled out to the end of the wing while folding and patting down the TP into the still damp surface. It only took a couple of minutes and my crowd of observers grew as their curiosity as to what the 'new guy' was up too. They thought I might have been spraying a teflon compound but that didn't explain the TP application. The tow plane landed and spun around to offer the tow rope as I did my final pre-flight inspection and climbed in the cockpit and buckled up. The tow pilot cut the engine as the safety launch officer had told him I was up to something with my plane and he had to come see what all the fuss was about. He was also one of my instructors and knew what a jokester I could be and he didn't want to miss the hullaboo. Other members were telling me that I had forgotten the TP on the wings but I just winked at the tow pilot/instructor and told him I was ready for launch.

    He sort of grinned and got back in the old cropduster that we towed with and off we went into the wild blue yonder. As we cleared the fence at the end of the grass strip and accelerated I looked and sure enough the dampness that had kept the TP plastered to the wings was drying out and at about 300' AGL it all started peeling off when I dipped down into the direct propwash of the towplane and took all the grass, dirt and bugs (lovebugs as this was in Florida) with the paper. Once we reached release altitude I announced my release and the tow pilot radioed, "I saw what you did there..."

    It was a great day for lift and I went on to have a three hour flight and upon landing I found that back in the hanger the towpilot had kept my secret about the toliet paper peeling off and everyone just assumed that the TP was the reason for my exceptionally long flight (for our near coastal flatlands area). They all figured that it must be some specially treated paper that promoted laminar flow as I had been talking a couple weeks earlier about a professor over at the University of Mississippi who had invented a special tape called a 'de-turbulator' that did indeed re-attach laminar flow further back on the wing yielding considerable Lift/Drag improvement and highest glide slope ratios. Everyone except the towpilot was impressed with the new students cleverness and said I would answer any questions about the method behind my madness after I had filled out my flight log. I opened my logbook and asked the towpilot across the hanger what day of the month it was and he played along with my joke and said, "Oh lets see, it is April First today..."

    It took a minute or to for that to soak in and someone finally figured out I was having a good old April Fool's Day Joke on the club.

http://www.deturbulator.org/

http://www.deturbulator.org/LowerSurfaceTape.pdf

 

NaClH20

Super ciliary
Surprised that you aviationists haven't discussed the possibly revolutionary Celera 500L.  The claimed specs look almost too good to be true.  We'll see, I guess.
Gotta admit I’ve been real curios about this one, too.  I’ve got a healthy skepticism for anything, aviation or otherwise, that includes the words “groundbreaking” “game-changing” “new paradigm” or any variation thereof.  This one seemed a bit different… They kept things under wraps pretty well, rather than the usual screaming press releases “New flying car will change the world!  Only two years away!” with slick digital renders before there is even one bit of functioning hardware.  They’ve been careful to say that the concept doesn’t scale, rather than leading one to believe that this would work for every possible use case. They’re not grifting deposits on YouTube with ridiculous over-promises.  I dunno… maybe that’s the ploy…. Play a little hard to get.  I guess I wish them well, as they seem pretty genuine and sincere, but I certainly don’t know enough about it to judge.

 

billy backstay

Backstay, never bought a suit, never went to Vegas
Gotta admit I’ve been real curios about this one, too.  I’ve got a healthy skepticism for anything, aviation or otherwise, that includes the words “groundbreaking” “game-changing” “new paradigm” or any variation thereof.  This one seemed a bit different… They kept things under wraps pretty well, rather than the usual screaming press releases “New flying car will change the world!  Only two years away!” with slick digital renders before there is even one bit of functioning hardware.  They’ve been careful to say that the concept doesn’t scale, rather than leading one to believe that this would work for every possible use case. They’re not grifting deposits on YouTube with ridiculous over-promises.  I dunno… maybe that’s the ploy…. Play a little hard to get.  I guess I wish them well, as they seem pretty genuine and sincere, but I certainly don’t know enough about it to judge.


You forgot "disruptive technology", or something like that?... :D

The Celera is definitely very different, and I wish them success!!

 

RedTuna

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What really caught my attention early on was the engine.  It kept being referred to as a diesel engine.  And I thought, "no way diesel fuel can work at those altitudes."  But the Red A03 is simply an advanced compression ignition (diesel cycle) piston engine running on aviation kerosene and, just recently, certified for biofuel.  I was irritated at myself, as I should know better.

 
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