Quote from: girishsarwal on September 28, 2013, 08:02:35 PM
"will a plane flying from east to west reach faster than the one moving from west to east, because the earth below is moving west to east"

get onto a balloon and stay still, once earth moves past land wherever you want to land, Simple !! (only catch is, it has to be on the same latitude, because earth moves only west to east not north to south or any other combo )

As sikat bhai mention,

Quote from: saikat on September 27, 2013, 10:36:27 PM
planes fly due to the lift generated by the wings which are caused
by the relative air moving over(and under) the wing.

Considering that lift acts perpendicular to the direction of airflow, irrespective of whether the plane is standing still or in motion, as long as there is some airflow over the wing, in a tractor setup, the plane should experience a certain amount of lift. For it to take off, the wings must genetate lift that's more than the weight of the plane; if that much lift can be produced, then the aircraft should take of vertically up like a VTOL craft before moving forward.

I derive my understanding from experimenting with a small wind tunnel. A while ago, i was fiddling around with some wing sections and a weighing scale to measure lift. The wings produced lift even while stationary, all it needs is airflow over the aerofoil section.
The same cannot the true with pusher setup and jet engines. there the airflow over the wing is generated by the motion of the aeroplane.

or I could be wrong too.

I had very similar thought when I was a kid, I had my own ideas shipping parcels to America, make a small rocket which will launch straight up and design such way that it will come down to the earth after 12 hours, by this time parcel will land safely in America.

Here if we make the example something different like tying a rope to a small glider and to the casing of a table fan, by the wind flowing, lift will be generated and glider will fly, but there is no momentum in the glider (as it is in a static position) and in real scenario it will be very difficult to control the aeroplane. With conveyor belt system the run up distance can be shortened, but plane should have it won momentum to control it.

QuoteThe wings produced lift even while stationary, all it needs is airflow over the aerofoil section.

Exactly what I feel. It is the same case if iron man is travelling at the speed of the airplane,.,for ironman the airfoil is stationary but still producing lift.

In our case, there is no effect on the airflow, but only the ground speed, by the conveyer, if the conveyer had any substantial effect on the airflow, the plane would levitate (and someone will have to firefight to control it perhaps, because sooner or later it will fall out of the direction of airflow. Whereas with a prop the airflow is always directed along the longitudnal axis of the plane.)

The theory of relativity talks about frames of reference. Gusty sir, I've never tried that in a balloon but afaik, with planes the rotation has no effect, of course some fluid laminars/jet stream have a part to play, but the rotation does not have any direct implications because all us observers are in the same time space and it will not have any significant, observable effect.

Quote from: rcpilotacro on September 28, 2013, 08:30:33 PM

Quote from: girishsarwal on September 28, 2013, 08:02:35 PM
"will a plane flying from east to west reach faster than the one moving from west to east, because the earth below is moving west to east"

get onto a balloon and stay still, once earth moves past land wherever you want to land, Simple !! (only catch is, it has to be on the same latitude, because earth moves only west to east not north to south or any other combo )

The balloon has to be flying higher than the Exosphere or 320 km above the Earth (or beyond into deeper space). Anything at a lower altitude else will cause the balloon to move along with the earth's rotation due to its gravitational pull.

God, why am I even indulging in such meaningless balloonist discussions???

This seems to be the most interesting topic in a while

Quote from: VC on September 29, 2013, 12:22:03 AM
The balloon has to be flying higher than the Exosphere or 320 km above the Earth (or beyond into deeper space). Anything at a lower altitude else will cause the balloon to move along with the earth's rotation due to its gravitational pull.

No it won't. Gravity will only pull it along the line joining their centers. Not all satellites move along with the earth's rotation (some move faster others slower, infact you can also make it stationary, but then it would fall down as there is nothing to generate lift in a satellite). Also, the moon is about 400,000 kms away. So, being higher than 320km will not diminish the gravitational pull. 

Quote from: girishsarwal on September 28, 2013, 11:30:58 PM
... the plane would levitate ....

The aeroplane (and the passengers in it, if there are) could Meditate to Levitate  

the wind blowing at the wings can be experienced when you try to make your bixler take off in a windy day. it holds its position and just goes straight up, even though there is no treadmill.

Sent from a potato using a lamp

Hahaha, Gusty sir, seems like Hyderabad has been more of a relaxing experience rather than flying

Talking of balloons, Col. S Sundaram will soon be making a RC Hot Air balloon using a Propane Soldering Iron as the heat source, and small ducts with servo controlled valves for direction

Anyone else ready for it?

Alright!

to put matters to rest (you can continue the levitation stuff though  ). Look at the image on top. these forces have to balance for an aeroplane to fly. AIr has to flow on top of the wings (This can be achieved by keeping aeroplane in a wind tunnel, or putting it against the wind etc) Whenever there is wind (even the slightest amount) there will be Drag. Now this drag has to be compensated with (a) Thrust (i.e. Engine) (b) by trading Gravity by putting the nose down (In slope soaring the aeroplane w.r.t wind is always descending, however the air is climbing faster than that that's why relatively she is climbing).

Lift is generated due to the wind that blows over the wings, when it equals weight the aeroplane lifts.

Once again see the diagram and understand the conotations,

PS
you will have to read this post carefully, may be once twice and imagine, whatever i am trying to say

Precisely Gusty sa'ab. Which is why one needs additional data in the form of the air condition around the wings as created by the environment. Without that the question is in the "insufficient data" category  

Quote from: anwar on September 28, 2013, 04:07:42 PM
Hmmm.. should this be a poll now ?  

Definitely Anwar Bhai would be interesting to see the results.

Sanjay Sir  How the hell did I get roped into middle of this balloon discussion  

Jallandhar has a very conducive environment for ballooning, Col. Saheb 

  Nevertheless it was a great idea of Balloon with Butane torch Sanjay Sir. Very Practical idea worth a try.

Quote from: sundaram on September 29, 2013, 07:10:42 PM
..great idea of Balloon with Butane torch Sanjay Sir. Very Practical idea worth a try.

true ! the more i think about it, more plausible it sounds

3 servos controlling 3 valves - for left, right (Ducts or pipes to directionally release hot air from the ballon....will need a neutral too to control excessive height) plus one for regulating the flame...higher or lower.

Apron (like hovercraft) material to make the balloon. Or parachute material

Quote from: sanjayrai55 on September 29, 2013, 07:20:45 PM
.will need a neutral too to control excessive height

no need ! atmosphere does that ! it equalizes temp very fast, in fact to maintain height you need to keep pumping in some hot air every now and then

How about landing, eg in an emergency (on-board Rx Battery low?)

And Sandy will have to keep a sharpshooter handy....in case it goes out of control. Don't want to lose the Radio equipment

And now, to bring back the original question in a modified form : will Sandy sir be able to fly and control this balloon while running on a treadmill? 

I am still unable to understand the concept of treadmill takeoff 

Just want discuss more on that, e.g. when we running on open ground, if the prime resistance is air, then the resistance is quite low when we are on a treadmill, or the automobile factories test the engine power/ wheel balance etc. on similar type of treadmills, my point is can they test the aerodynamic characters of a particular vehicle (its body shape) by running it on a treadmill, I think No. because the vehicle is moving relative to the surface but not against the wind.
   
At present I am using the laptop and unable draw a diagram what I was trying to explain previously (the table fan and glider part). At low wind speed the glider will remain nose up (drag + weight > thrust + lift) (here thrust is the tension in the rope). Nose down on heavy wind ( drag + weight < thrust + lift). Now at this point if we have engine (thrust) greater than (drag+weight+lift) it will move forward. So what I am trying to conclude is there is no role of treadmill while taking off but entirely depends the engine power. I may be wrong... or there is something wrongly presented in the video .......... chalta hey.