geogob
Koohii o nomimasu ka?
Actually, you are all confused by one impression... is that the wheels play a role in the acceleration of the plane. A plane is not a car.
The engines are pushing air behind them, which creates thrust. The wheels are only an accessory to support the plane on the ground. The plan could be on skis, floats, what ever. Wheel are only nice because they offer less resistance, hence reduce the force needed to co against friction on the ground during acceleration. But it is not the friction with the ground that accelerates the plane, like it would with a car. For braking, it's another story... a plan brakes pretty much like a car.
If you set a plane on a large rolling band, put take off thrust, the plane would take off pretty much normally. It would accelerate and take off. Only difference is that the ground below the wheels would start moving the opposite direction. So at takeoff, the airspeed would be the same, as with any takeoff and the speed relative to the ground that is not moving also the same. Only the speed relative to the "runway" would be twice as high. You would need the same distance to take off. You would need more energy considering you have to accelerate your huge 2 miles long conveyor. Hence, all this discussion is pretty much useless. Basic physics. High School.
On airspeed:
Harrm, it looks like you disagree with the use of this word. Well, airspeed is the technical word use in aviation to indicate the speed of the aircraft relative to the air surrounding it. The term is used to avoid confusing with the ground speed. You never use the word "speed" alone in aviation because of the possible confusion. Ground speed is measured by radar, GPS, Navigation radios or using calculation from the airspeed and known wind speed and direction. Airspeed is the usual speed used in aviation because ALL flight dynamics and aircraft limitation depend on airspeed alone. Ground speed, as I said, is used only to calculate time in route during navigation. Airspeed is measured using a pitot tube. It's a tube facing towards the front of the aircraft. The airflow induced by the forward movement of the plane increases the pressure in the pitot tube. A static pressure measurement point measures the atmospheric pressure. The difference between the two pressures (pitot and static) gives you the pressure induced by the airflow, allowing you to calculate the airspeed.
The official terminology of the word "airspeed" is to use it in one word. On the contrary "ground speed" has not been officially recognised to be used in one word. The two words "ground" and "speed" are never used in one single word.
Just as a note (I think there are already too much details here), there are different kinds of airspeed. True airspeed, measured airspeed, indicated airspeed, etc. This is mainly due to the fact that no measurement instruments in an aircraft are precise at 100%. They all have errors, limitation and such. This is true with airspeed as with most of the on board instruments.
The engines are pushing air behind them, which creates thrust. The wheels are only an accessory to support the plane on the ground. The plan could be on skis, floats, what ever. Wheel are only nice because they offer less resistance, hence reduce the force needed to co against friction on the ground during acceleration. But it is not the friction with the ground that accelerates the plane, like it would with a car. For braking, it's another story... a plan brakes pretty much like a car.
If you set a plane on a large rolling band, put take off thrust, the plane would take off pretty much normally. It would accelerate and take off. Only difference is that the ground below the wheels would start moving the opposite direction. So at takeoff, the airspeed would be the same, as with any takeoff and the speed relative to the ground that is not moving also the same. Only the speed relative to the "runway" would be twice as high. You would need the same distance to take off. You would need more energy considering you have to accelerate your huge 2 miles long conveyor. Hence, all this discussion is pretty much useless. Basic physics. High School.
On airspeed:
Harrm, it looks like you disagree with the use of this word. Well, airspeed is the technical word use in aviation to indicate the speed of the aircraft relative to the air surrounding it. The term is used to avoid confusing with the ground speed. You never use the word "speed" alone in aviation because of the possible confusion. Ground speed is measured by radar, GPS, Navigation radios or using calculation from the airspeed and known wind speed and direction. Airspeed is the usual speed used in aviation because ALL flight dynamics and aircraft limitation depend on airspeed alone. Ground speed, as I said, is used only to calculate time in route during navigation. Airspeed is measured using a pitot tube. It's a tube facing towards the front of the aircraft. The airflow induced by the forward movement of the plane increases the pressure in the pitot tube. A static pressure measurement point measures the atmospheric pressure. The difference between the two pressures (pitot and static) gives you the pressure induced by the airflow, allowing you to calculate the airspeed.
The official terminology of the word "airspeed" is to use it in one word. On the contrary "ground speed" has not been officially recognised to be used in one word. The two words "ground" and "speed" are never used in one single word.
Just as a note (I think there are already too much details here), there are different kinds of airspeed. True airspeed, measured airspeed, indicated airspeed, etc. This is mainly due to the fact that no measurement instruments in an aircraft are precise at 100%. They all have errors, limitation and such. This is true with airspeed as with most of the on board instruments.
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