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airship
24th Jan 2015, 12:26
More accurately, at the precise moment just before the last wheel left the ground...

Would the aircraft have a faster climb rate, if only momentarily?

This article (http://www.economist.com/news/science-and-technology/21639436-new-tool-quest-understandand-co-optnatures-secrets-flying-flight) from the Economist newspaper might bring a fresh perspective to such important considerations. And perhaps of interest to the residents here including conveyor-belt afficionados?

http://cdn.static-economist.com/sites/default/files/imagecache/290-width/images/print-edition/20150117_STD001_0.jpg

PS. I've heard of whole plane-loads of chicks being flown across the globe in cargo (jumbo) jets, so the subject may have some implications for aviation professionals in this sector...

chksix
24th Jan 2015, 12:34
This conundrum was tested by Mythbusters. No change to total weight unfortunately.

OFSO
24th Jan 2015, 12:42
Might make a difference if it was a Ryanair load of SLF's.

I was on an Air India 747 once where at least half the passengers were walking about talking to other passengers during take off /rotation. Didn't seem to make any difference....

airship
24th Jan 2015, 13:07
WOW chksix, the 2 parrots have appeared on Mythbusters?! Parroting the article: Gaga and Ray created lift equivalent to twice their body weight on the downstroke and virtually none on the up. Were they to flap in synchrony, then, the apparent weight of the birds in a lorry could briefly double.

Um... lifting...
24th Jan 2015, 13:54
And if the parrots flapped at the natural resonance frequency of the aircraft?

I think we should be told.

Hempy
24th Jan 2015, 14:12
The Earth rotates at 1,675 km/h, so how come if I jump in the air for one second I don't land 465 meters to the west?? :}

airship
24th Jan 2015, 14:19
Hmmmmmm...

http://upload.wikimedia.org/wikipedia/commons/thumb/1/16/Archilochus-alexandri-002-edit.jpg/800px-Archilochus-alexandri-002-edit.jpg

Wikipedia (http://en.wikipedia.org/wiki/Hummingbird): ...rapid wing flapping rates, typically around 50 times per second,[1] but possibly as high as 200 times per second...

50-200Hz is more than I could ever hope to achieve in my wildest dreams hands-only.

MadsDad
24th Jan 2015, 14:26
The Earth rotates at 1,675 km/h

At the Equator. If you happen to be at the North/South Pole the rotation speed will be zero km/h. Somewhere in the middle gives anywhere from 464 to 1 metre to the left.

meadowrun
24th Jan 2015, 15:35
Perhaps similar to the elevator cables snapping at the 40th floor and plunging. Can jumping up at the split second before it hits earth save you?


Nope...still a meat bomb.

airship
24th Jan 2015, 15:52
henry wrote: Strange that folk here don't know schoolboy physics. Oh well, it is jb......

What part of: Gaga and Ray created lift equivalent to twice their body weight on the downstroke and virtually none on the up. Were they to flap in synchrony, then, the apparent weight of the birds in a lorry could briefly double.
do you fail to comprehend?

You've completely ignored the point that the pax (2 parrots in this case) effected their initial downstroke (and when the wheel/s were still on the ground). Forgetting the basics (Ie. MC²) and the additional energy (produced by the pax / parrots) available to the aircraft during climb... :}

Loose rivets
24th Jan 2015, 15:56
'Fine' the man answered as he fell past the first floor. :\



(or second floor in US)

airship
24th Jan 2015, 16:54
henry, OK:

http://upload.wikimedia.org/math/4/6/d/46d9fd53de36a1fc22d818633b0b18b9.png

Happier?! Anyway, you've been on here long enough to know that:

http://www.pprune.org/images/3flypigs.gif

OFSO
24th Jan 2015, 17:48
You should try turning in circles with a magnet held in each hand:

http://i656.photobucket.com/albums/uu287/ROBIN_100/Locke%20Derivation_zpsjn6irysu.jpg

Where P = magnetic moment, C = velocity of light, B is a constant of 0.25 (don't ask me why) and U is the angular momentum. G is gravity.
Spin fast enough and you'll rise in the air....


(Locke Derivation)

(A prize of one wooden euro for the first person to tell me in which novel this equation plays a major rôle).

airship
24th Jan 2015, 17:56
Ahh yes, Beachy Head. So many mixed memories of those days. Playing truant to escape all those innocent and harmless taunts from my fellow school-goers. A can of Coca Cola cost less than 10 (new) pence. Watching a few Chinese and other shell-fish gatherers out on the beach during low-tides. Sleeping the care-free days away under the warm summer sun until time to cycle home to Lower Willingdon (or was it Upper Willingdon?). Only rarely climbing up the slopes to the top of the cliff-face. Perhaps wondering how far one could glide. Or Pakis fly. An opportunity to enjoy the real (at least momentary) sensation of Einstein's theories, even if not actually learning about them in any classroom. Now, hardly 40 years later, here in this classroom...?! :(

OFSO
24th Jan 2015, 18:05
until time to cycle home to Lower Willingdon

Passing, as it probably happened, my dad returning from walking on the Downs to his home in Willingdon Park Drive.

Small world.

Windy Militant
24th Jan 2015, 18:20
Is the aircraft, passengers or both on a conveyer belt? We need to know! :p

(A prize of one wooden euro for the first person to tell me in which novel this equation plays a major rôle).
I claim my Wooden Euro
The relevant equation is the Locke derivation of the Dirac-Blackett equation
Which was claimed to be the Principle behind The Dillon-Wagoner Graviton Polarity Generator, known colloquially as the spindizzy, and the Novel was James Blish's Cities in Flight. ;)

oxenos
24th Jan 2015, 22:05
"The Earth rotates at 1,675 km/h, so how come if I jump in the air for one second I don't land 465 meters to the west?? "

You do. But the earth has rotated by the same 465 metre, so you land in the same spot on the earth.

It's all relative.

Harvard1964
24th Jan 2015, 22:17
Just to complicate jumping in a falling elevator a bit more. Relative to the falling elevator one would be weightless. As such it would be difficult to swim in the air to get to the floor of the elevator, I think.... Too late, I'm a goner, took too long to think about it......

Fishtailed
25th Jan 2015, 00:36
I've heard of whole plane-loads of chicks being flown across the globe in cargo (jumbo) jets,


Was that the 60s man, or just modern human trafficking!!




Sorry, hat, coat etc.

ruddman
25th Jan 2015, 03:38
This thread is as baffling as the mounted, turning crow one.


Here's one:

If one put a slip and slide down the aile of a 747, and you sat at the front end of the slide when it rotated, what speed would you reach as you neared the end of your slide journey approaching the rear galley? And how long would it take? Assuming wearing a regular pair of board shorts and typical soap sud usage and using regular 747 SOP with ISA+10 slip and slide performance charts.





Work that one out, maths (math*) nerds. :8






*for those amongst us that delite in the alternate version of English.

meadowrun
25th Jan 2015, 03:50
Need more data...
B742 or B748?
Interior configuration and any doglegs?
Angle of rotation?
Vr speed?
Interior temperature?
Maker and material of slip and slide?
Your weight?
Do you have your wallet in the right rear pocket?
How many fat bastards legs overflowing into aisle?
Anyone throwing bags of peanuts at you as you pass?
Any galley carts in the aisle?
How high can the flight attendants jump?
Can you see up their skirts?

OFSO
25th Jan 2015, 07:57
Er - a wooden Euro for ol' henry ?

Just waiting until it gets a bit smaller to save postage to you......although I suspect by the time it gets there you will need a magnifying glass !

Hobo
25th Jan 2015, 08:23
On a T3 from LHR to PWK for some base training with about 20 on board. When we arrived at PWK and by the start of the downwind leg on the first circuit all 20 of us had, one by one, moved as far forward in the cabin as possible. Half way down the leg when it was all nicely stable and trimmed out we all rushed, as one, right down to the back. Quite a trim change followed.

Tankertrashnav
25th Jan 2015, 10:01
In the back of a fully laden Victor K1 on a hot day there was a definite temptation to pull up on the edge of your seat as you waited (interminably it seemed) for the co-pilot to call out "rotate"!

airship
25th Jan 2015, 17:08
What if each passenger / chick also had a suitably-sized helium-filled balloon to either wholly (or partially) reduce their real weight inside the cabin / hold etc.?

Is their a gas even lighter than helium which the boffins might one day invent?

Maybe airlines operating the A-380 (or future double-deck 747s) could use the whole upper-deck for helium-filled balloons on some flights...?! Maybe the USAF could also use these balloons to fill the void space when transporting Abrams tanks in C5s?

G-CPTN
25th Jan 2015, 17:37
Nuffink is lighter than hydrogen, Shirley (and it's cheap, too).

airship
25th Jan 2015, 18:13
Oh henry: innuendo? When said with a Japanese accent, sounds like... :zzz:

You're a smart chap. You'll eventually work it out.

ruddman
26th Jan 2015, 12:09
Need more data...
B742 or B748?
Interior configuration and any doglegs?
Angle of rotation?
Vr speed?
Interior temperature?
Maker and material of slip and slide?
Your weight?
Do you have your wallet in the right rear pocket?
How many fat bastards legs overflowing into aisle?
Anyone throwing bags of peanuts at you as you pass?
Any galley carts in the aisle?
How high can the flight attendants jump?
Can you see up their skirts?


Ok. Let's try this out.

B742 or B748? 747-200 YR : Vintage Airline Seat Map: United Airlines Boeing 747-200 YR - Frequently Flying (http://frequentlyflying.boardingarea.com/vintage-airline-seat-map-united-airlines-boeing-747-200-yr/)

Interior configuration and any doglegs? See above diagram. We will position the slide so the beginning point is near row 20C to avoide that little dogleg just before that row. Looks like a straight run all the way to the rear.

Angle of rotation?
Vr speed? Let's say 10 degrees which I think would be more then enough to achieve a reasonable speed down the slide. Vr? Well, say a less that max TOW. Bit of googling...600,000lb. What would a flap 10 Vr speed be? 150-160? Help 747 drivers.

Interior temperature? I'm not taking my shirt off for anything less then 30C. Yeah a little steamy, but it's just a short experiment.

Maker and material of slip and slide? check this sucker out : 50' long 10' wide PVC, the Super Sweet Slide inflates the fun for summer with a giant slip and slide with families and friends. Huge lawn water slide! (http://www.funair.com/SUPER-SWEET-SLIDE-Giant-Slip-n-Slide-p/ssss300.htm)
Absolutely made to fit the aile of a 747-200 from row 20.

Your weight? How dare you. Hmm...ok....gulp. 87kg. 192lb.


Do you have your wallet in the right rear pocket? Nope. Never do that ever. Easy target for pickpockets and no good for slip and slides.

How many fat bastards legs overflowing into aisle? Depends on how many of you are coming along for the ride. ;) Lets say none.


Anyone throwing bags of peanuts at you as you pass? I'm sure there are some who'd like to throw more then that. :} 3 packets get thrown total.


Any galley carts in the aisle? Nope. Stowed away.

How high can the flight attendants jump? They safely out of the way.

Can you see up their skirts? I've recently been accused of being sexiest here so no, I won't be looking. :mad:




Oh my. Hardest thing about that was doing it on my iPad. Painful.
So....speed and time down the slide? Oh, and a rear door slide has been inflated for the slowing down part at the end. Would be nice to actually try it without seats, but, that all adds to the thrill I guess of nearly hitting them.

angels
26th Jan 2015, 15:46
OFSO -

Passing, as it probably happened, my dad returning from walking on the Downs to his home in Willingdon Park Drive.

And possibly carrying on to Wrestwood Avenue, one street away, and seeing my Little Grandad who lived there.

As you say, small world.....