BBS: TELESC.NET.BR Assunto: Conveyer belt question De: Vincent Coen Data: Thu, 26 Feb 2026 21:34:12 +0000 ----------------------------------------------------------- Hello Rug! 26 Feb 26 14:47, you wrote to me: My comment where NOT related to a road vehicle what ever but an aircraft that depends on forward motion in combination with AIRFLOW over its surfaces i.e. wings. By the very fact that the a/c is stationery in relation to airflow nothing is going to happen. Stop comparing to a road vehicle - it is not the same what so ever. > You are still in box created by the comparing it to a car. > The wheels on an airplane have nothing to do with propelling the > aircraft forward. The motive force (Thrust) is provided by a > completely seperate sorce (Propeller or jet). The wheels just > freespin (Or are just along for the ride). Since they don't provide > the force pushing it forward the belt is not acting against this > force. Aircraft moves forward and will reach takeoff speed. > If you want to compare it to the car, since this is what hangs people > up. > Let's do this experiement with the car. > Belt matches motive force caused by engine transfering power to the > wheels and friction on between the tires and treadmill cancel each > other out, car does not move... > With out changing anything. Acelleration force on the car or > treadmill speed (Or those metal rollers on a speedometer calibration > or smog check station). > Now get behind the car and push it.. What happens? The car will move, > because you are applying a second force which will become additive to > 2 other forces in opposition to each other. Lets assign this an > arbitrary value of 2. > so say car moving forward is 60 treadmill is 60 60-60=0+2=2. You > have a net positive force of 2. > Airplane. Wheels have ZERO motive force, but we will still assign > them a speed value (You will see why in a second..) > SO everyting is at idle. treadmill is not moving, engine isn't > providing thrust, tires are not spinning. > So we apply thrust so that number will go up exponentionally. > Tread mill and tires match their speed. increasing exponentionally, > Your Cesna lets say has a Vr of 80kts. WHEELS 80 - Treadmill 80 = 0. > However we are not done... Becaue like you pushing the car from behind > with have the thrust value for the propeller of +80 0+80 still = 80 > and you will take off. (That is the visual demonstration), because in > the real world the wheel rotational speed would be twice as fast. > The aircraft will take off. > If STILL won't listen. There are plenty of Youtube videos on it. > https://www.youtube.com/results?search_query=airplane+treadmill+mythbu > sters > Rug Rat (Brent Hendricks) > Blog and Forums - www.catracing.org > IMAGE BBS! 3.0 - bbs.catracing.org 6400 > C-Net Amiga BBS - bbs.catracing.org 6840 Vincent --- Mageia Linux v9 X64/Mbse v1.1.7/GoldED+/LNX 1.1.5-b20240604 * Origin: Air Applewood, The Linux Gateway to the UK & Eire (2:250/1) ----------------------------------------------------------- [Voltar]