RunRyder RC
WATCH
 8 pages [ <<    <     5      6     ( 7 )     8     NEXT    >> ] 5043 views POST REPLY
HomeOff Topics › Airplane in a wind tunnel
02-05-2008 02:46 AM  10 years agoPost 121
GimbalFan (RIP)

rrProfessor

Big Coppitt Key, FL

My Posts: All  Forum  Topic

I don't really care one way or another how you feel about it.
Wrong.
Wrong again.

op-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-t

PM  EMAIL  GALLERY  Attn:RR  Quote
02-05-2008 02:51 AM  10 years agoPost 122
scatbass

rrNovice

Hiram, GA

My Posts: All  Forum  Topic

I don't really care one way or another how you feel about it.
Wrong.
Wrong again.
2 wrongs don't make a right.



Mike

PM  EMAIL  Attn:RR  Quote
02-05-2008 02:53 AM  10 years agoPost 123
legoman67

rrElite Veteran

Nanoose Bay B.C, Canada

My Posts: All  Forum  Topic

it wont fly...

PM  EMAIL  GALLERY  Attn:RR  Quote
02-05-2008 02:53 AM  10 years agoPost 124
GimbalFan (RIP)

rrProfessor

Big Coppitt Key, FL

My Posts: All  Forum  Topic

2 wrongs don't make a right.
Agreed. The combined foolishness of both of you being wrong about the simple wording of a simple question does not make either of you right.

op-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-t

PM  EMAIL  GALLERY  Attn:RR  Quote
02-05-2008 03:57 AM  10 years agoPost 125
1stPlace

rrApprentice

Ohio USA

My Posts: All  Forum  Topic

The combined foolishness of both of you being wrong about the simple wording of a simple question does not make either of you right.
Definitions of forward (direction):
verb- Towards the direction that is in front of you
adjective- forward motion/movement

Definitions of speed:

noun- how fast something moves (notice, there is no frame of reference, making this definition very ambiguous)
verb- a very fast movement
noun- how fast something happens
adjective - very quick or fast
What's poorly worded about it? It's grammatically correct and unambiguous.
"forward speed" is unequivocally ambiguous. For you to claim otherwise is fatuously absurd!

If the question intended "forward speed" to mean airspeed, than take off is inevitable.

Airspeed= 50MPH, Tailwind= 50MPH(relative to airspeed), Speed relative to fixed point= 100MPH

If it intended "forward speed" to mean speed relative to a fixed point, then you have to throw the airplanes thrust out the window in order to achieve a 0 airspeed condition, or have a magical wind tunnel that can somehow cancel out the airplanes thrust!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-05-2008 04:24 AM  10 years agoPost 126
cannibal440

rrApprentice

cookeville, tennessee USA

My Posts: All  Forum  Topic

the airplane will not fly; it will be blown backwards due to the drag. only way to actually make a plane hover inside a wind tunnel is to cable it in one place so the wind wont be able to push it backwards and the wind cutting across the airplane would give it flying capabilities. you must have a cable securing the plane in place or no matter how fast the wind is blowing it will do nothing more than push the plane backwards.

now if the wind tunnel is infinite in size you have to keep INCREASING the airspeed to make up for the drag difference. a constant airspeed would do nothing except break a good airplane.....unless of course you have it tethered so it stays still.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-05-2008 04:38 AM  10 years agoPost 127
1stPlace

rrApprentice

Ohio USA

My Posts: All  Forum  Topic

Cannibal,
Are you reading the same question we are?
In an airplane was sitting in a wind tunnel that was infinitely large and the wind generater was designed to match the forward speed of the plane from behind, can the airplane take off?
I read that as a plane trying to take off, not as a plane trying to hover.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-05-2008 06:54 AM  10 years agoPost 128
cannibal440

rrApprentice

cookeville, tennessee USA

My Posts: All  Forum  Topic

there would be no forward speed...only backwards

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-05-2008 12:20 PM  10 years agoPost 129
bagobitz

rrVeteran

saddleworth,lancs,UK

My Posts: All  Forum  Topic

Mike and "firstplace"

Yes, you're quite correct that "forward speed" is ambiguous OF ITSELF

However, It was NOT an unqualified direction. the wind matched it from BEHIND, also, of course,a 'plane has a "front" and a "back"

the term"forward" as applied to "plane" would therefore indicate that any move from the static position, would see the "front"PRECEDE the "back"

In plain, simple english "forward is the NORMAL direction and orientation of a moving aeroplane.

see also my previous post .

I once worked with medical equipment, -we tried to design the stuff "idiot-proof"...hopefully, then ,it would be "nurse-resistant"

Your confusion over a simply and concisely worded puzzle , is the reason Technical Authors are highly paid....they make clear, precise and unambiguous writings....(except pidgin-english Japanese instructions, -even they are better of late!)

PM  EMAIL  Attn:RR  Quote
02-05-2008 02:19 PM  10 years agoPost 130
rander1

rrNovice

Dallastown, PA

My Posts: All  Forum  Topic

Original problem updated

Tic Toc Tic Toc

PM  EMAIL  Attn:RR  Quote
02-05-2008 02:27 PM  10 years agoPost 131
1stPlace

rrApprentice

Ohio USA

My Posts: All  Forum  Topic

Your confusion over a simply and concisely worded puzzle , is the reason Technical Authors are highly paid....they make clear, precise and unambiguous writings.
And therein lies the problem. If the terms "forward speed" were unambiguous, this would not even be a debate. If it were clear and concise, it would clearly state that the wind matches the forward speed of the plane, relative to a fixed point, or that the windspeed matches the forward airspeed.

Since an airplanes speed can be defined as speed across the ground, or as airspeed, the question is not clear and concise. It is all in how you interpret "forward speed".

Also, to an airplane that is trying to take off, airspeed is all that matters, and flying implies airspeed, not "speed relative to a fixed point"

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-05-2008 02:29 PM  10 years agoPost 132
1stPlace

rrApprentice

Ohio USA

My Posts: All  Forum  Topic

Original problem updated

In an airplane was sitting in a wind tunnel that was infinitely large and the wind generater was designed to match the forward AIRspeed of the plane from behind, can the airplane take off?
Rander, you could have said that the first time and saved me a whole bunch of typing!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-05-2008 02:35 PM  10 years agoPost 133
1stPlace

rrApprentice

Ohio USA

My Posts: All  Forum  Topic

GimbalFan,
Now that the author has defined speed... ya' still wanna bet?

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-05-2008 04:01 PM  10 years agoPost 134
bagobitz

rrVeteran

saddleworth,lancs,UK

My Posts: All  Forum  Topic

still a total sideshow!

the wind -generator matches the forward speed FROM BEHIND

there is NO airspeed!!!!!

clue:- it's from behind and matches the forward speed of the plane.
he wind generater was designed to match the forward speed of the plane from behind,
seems quite unequivocal to me! the plane moves in the same direction as the "wind" and at the same speed
clue..."forward speed of the plane"

I am aware that"American English" uses different spellings to UK, I'm also aware that the odd (very odd) word like "fag" has a totally different meaning to it's original UK definition,
but I wasn't aware you'd reassigned a substantial portion of our dictionary....more puzzling because the vast majority of US citizens (and those in the Antipodes, African continent, Europe and the East and far East)with whom I converse here, have no difficulty assigning an accurate and true meaning to my words.
as Gimbal said,-"back to school"

PM  EMAIL  Attn:RR  Quote
02-05-2008 06:17 PM  10 years agoPost 135
1stPlace

rrApprentice

Ohio USA

My Posts: All  Forum  Topic

with whom I converse here, have no difficulty assigning an accurate and true meaning to my words.
I have no trouble understanding your words. It was the original question, which was not authored by you, that was unclear. Your wording has been perfectly clear.

Now that the question has been more clearly written to include airspeed (my original interpretation), do you still think the plane won't take off?

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-05-2008 06:22 PM  10 years agoPost 136
SSN Pru

rrElite Veteran

Taxachusetts

My Posts: All  Forum  Topic

Now it's worded like the treadmill problem.

In order for the treadmill to move backwards, the plane HAD to move forwards which hinted that the aircraft was allowed to move relative to a fixed point.

Now this problem is worded to say that the tail wind will only blow if the aircraft has forward airspeed not groundspeed.

Stupidity can be cured. Ignorance is for life!

PM  EMAIL  GALLERY  Attn:RR  Quote
02-06-2008 11:23 AM  10 years agoPost 137
bagobitz

rrVeteran

saddleworth,lancs,UK

My Posts: All  Forum  Topic

Umdpru has the correct understanding! the "reworded"puzzle is totally different to the first one.

for the purposes of clear understanding:-

The information in the original puzzle allowed the following UNAMBIGUOUS deductions
the aircraft was allowed to move freely in a NORMAL direction of progress-IE the front preceeding the back.front-to-rear axis aligned with direction of travel.

the direction , with respect the ground has no relevance whatsoever

the "wind"is on the same longitudinal axis as the aircraft and matches it's speed from the back

as the plane and the wind are both moving on the same axis, at the same speed, relative to each other, they are STATIC,RELATIVE TO EACH OTHER. (matched speed!)

I think you need to carefully reappraise the original proposition and understand which words your mind is "blanking " or reassigning"

PM  EMAIL  Attn:RR  Quote
02-06-2008 11:48 AM  10 years agoPost 138
GimbalFan (RIP)

rrProfessor

Big Coppitt Key, FL

My Posts: All  Forum  Topic

Now that the author has defined speed... ya' still wanna bet?
Depends entirely upon whether or not you've managed to overcome your linguistic hurdles. Can you answer either of these two questions correctly?

Original question:
If an airplane was sitting in a wind tunnel that was infinitely large and the wind generater was designed to match the forward speed of the plane from behind, can the airplane take off?
New question:
If an airplane was sitting in a wind tunnel that was infinitely large and the wind generater was designed to match the forward airspeed of the plane from behind, can the airplane take off?

op-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-thwop-t

PM  EMAIL  GALLERY  Attn:RR  Quote
02-06-2008 02:13 PM  10 years agoPost 139
1stPlace

rrApprentice

Ohio USA

My Posts: All  Forum  Topic

I have been answering correctly since the first question was asked. It's you and bago that have been assigning meanings to words that were too ambiguous to be clearly defined. And, since neither of you can or will admit that, I am done arguing.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-06-2008 02:16 PM  10 years agoPost 140
SSN Pru

rrElite Veteran

Taxachusetts

My Posts: All  Forum  Topic

I have been thinking this over long and hard. I had a sleepless night last night because I had nightmares of airplanes in wind tunnels and on treadmills chasing me lol.

this riddle, as I see it now, falls in line more with the treadmill answer. In order for the air to blow on the tail, the airplane has to have forward airspeed. For the tail wind to increase in velocity, the forward airspeed must also increase in velocity by an equal margin. It seems to me that the airspeed would be increasing at some multiple of the tail wind in order for both the airspeed and the tail wind to continue to increase.

That's as far as I've gotten for now in my analysis.

Stupidity can be cured. Ignorance is for life!

PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 8 pages [ <<    <     5      6     ( 7 )     8     NEXT    >> ] 5043 views POST REPLY
HomeOff Topics › Airplane in a wind tunnel
 Print TOPIC  Make Suggestion 

 9  Topic Subscribe

Sunday, December 9 - 11:59 pm - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

The RC discussion world needs to consolidate. RR is now one choice for that. Its software is cutting edge. It hosts on-topic advertising. Help RR increase traffic buy making suggestions, posting in RR's new areas (sites) and by spreading the word.

The RunRyder Difference

• Category system to allow Rep/Vendor postings.
• Classifieds with sold (hidden) category.
• Classifieds with separate view new.
• Answer PMs offsite via email reply.
• Member gallery photos with advanced scripting.
• Gallery photo viewer integrated into postings.
• Highly refined search with advanced back end.
• Hosts its own high end fast response servers.
• Hosts thousands of HD event coverage videos.
• Rewrote entire code base with latest technology.
• No off-topic (annoying) click bait advertising.
Login Here
 New Subscriptions 
 Buddies Online