Date: 13 Feb 99 02:26:11 From: email@example.com (Stephen H. Westin) Organization: Cornell University Program of Computer Graphics References: 1 2 3 4 5 Followups: 1
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JF Mezei <firstname.lastname@example.org> writes: > I do not understand. If the static pressure trapped inside the system > were enough to show a V1 speed on the pilot's gauges, shouldn't pilots > have noticed that the gauges were reading V1 while the plane was iddle? No. There are two ports involved: one is a tube facing forward and measuring ram air pressure, which depends (to first order) on airspeed. This presumably wasn't blocked. The second port is needed because planes don't stay at a constant altitude: as outside static air pressure declines with altitude, the ram air pressure (as absolute pressure) declines. To correct for this, the airspeed indicator has a static port open to the non-pressurized atmoshpere outside the plane and registers the pressure *difference*. I believe that this static port was blocked, giving a normal airspeed indication on the ground, but progressively stranger readings as the plane climbed. -- -Stephen H. Westin Any information or opinions in this message are mine: they do not represent the position of Cornell University or any of its sponsors.