Question

After the 2010 eruptions of the eyjafjallajökull vulcano in iceland, air traffic (including general aviation) was suspended for days in large parts of europe. even glider aircraft were initially not allowed to fly: authorities were afraid that the static ports of the glider would get blocked by the ash, which would cause the altimeter to remain at zero altitude and the speed indicator to display incorrect values. consider a glider flying at 400m, when all of the sudden the static ports get blocked due to volcanic ash. the pressure at this altitude is 96610 pa. it then descends to sea-level where it flies at a true airspeed of 25 m/s. what is the airspeed indicated by the pitot-tube driven airspeed indicator in m/s?

Answer 1

The airspeed indicated by the pitot-tube-driven airspeed indicator will be zero m/s if the static ports of the glider get blocked by volcanic ash.

Step-by-step explanation:

The airspeed indicated by the pitot-tube-driven airspeed indicator can be calculated using the total pressure and static pressure. In this case, when the static ports of the glider get blocked by volcanic ash, the airspeed indicated by the pitot-tube-driven airspeed indicator will be incorrect.

To calculate the airspeed, we need to find the difference between the total pressure and the static pressure. Total pressure is the sum of the static pressure and the dynamic pressure, which is proportional to the square of the airspeed. Static pressure is the pressure of the surrounding air. We can use the equation:

Total Pressure = Static Pressure + Dynamic Pressure

Given the static pressure at sea level is 96610 Pa, and the glider is flying at a true airspeed of 25 m/s, we can calculate the dynamic pressure as:

Dynamic Pressure = Total Pressure - Static Pressure

Since the glider is flying at sea level, the dynamic pressure will be zero, resulting in an airspeed indicated by the pitot-tube-driven airspeed indicator of zero m/s.