>In the simplest of terms - A of A is the angular diff between where the >airplane is pointing and where it is going - think about it. >I am not sure what value A of A will have in alerting a pilot to >stalling CONDITIONS. >Steve J ++++++++++++++++++++++++++++++++++++++++++++++++
Also from the site I referenced before: [[ The 'stall' is the breakdown in the smooth airflow over the upper wing surface, that starts to occur when the wing nears a particular angle of attack for light aircraft, without high-lift devices, usually around 16°. This critical angle of attack has no relationship either with the aircraft attitude or the aircraft velocity it can readily be reached in a high speed dive but it does have a direct relationship with elevator position and thus the control column position. ]] The fact that the wing will always stall at the same angle is why the "tab" and "flute" work. In the case of the "tab" it is adjusted so that when the wing is very near the stall A of A the pressure on the bottom side of the tab is greater than the pressure on the top side. The tab moves up and trips a switch, the buzzer sounds, the pilot releases back pressure, the nose drops, the A of A decreases, the tab lowers , the switch opens, the buzzer shuts off, yada, yada, yada......... As for the statement: "In the simplest of terms - A of A is the angular diff between where the airplane is pointing and where it is going - think about it." Once that angular difference exceeds the stall A of A for that wing the wing will stall. The stalling of the wing has only to do with the angle at which the on-coming air strikes the cord line of the wing. When it reaches the critical angle the air on the top side separates and the stall occures. The reason Ken Rand put 3 degrees washout (twist) in the wing is so the stall will start at the root of the wing while the outboard section with the ailerons are at a smaller A of A and continues to fly. There is other valuable info you can get from A of A meters that will help fly the aircraft more safely and efficently but I'm not well enough versed to expound on them. I'm sure you'll see the big commerical stuff follow the lead of the military in the use of the A of A instruments if they haven't already. Larry Flesner
