Pressure Sensing Flashcards
If static ports become blocked, can static pressure be obtained some other way?
Yes, via the alternate static source that takes air from the cockpit.
How is dynamic pressure also called?
Kinetic energy of the air.
Define: differential pressure.
The difference in pressure between two places.
If static pressure is supplied to the altimeter from the alternate static source, the altimeter over-indicates. Why?
Because the alternate static source uses air from the cabin, and the cabin is not perfectly sealed (air leaks out). This creates slight suction which decreases static pressure.
Define: total pressure formula.
PT = PS + PD
State which pressure sources do following instruments require:
(a) ALT
(b) VSI
(c) ASI
(d) MM
(a) static
(b) static
(c) static + pitot
(d) static + pitot
Define: pressure.
Force per unit area.
How is static pressure also called?
Atmospheric pressure or ambient pressure.
Define: pressure formula.
P = F / A.
Why must static ports be installed in pairs (on both sides of the aircraft)?
To eliminate yaw effects.
Define: gauge pressure.
Differential pressure relative to ambient air.
Define: aneroid.
Without flow.
What is the relationship between atm, bar, mbar, hPa, and Pa?
1 atm ≈ 1 bar = 1,000 mbar = 1,000 hPa = 100,000 Pa
Which errors do altimeters suffer from?
IMP (instrument, manoeuvre, position).
State the names of the instruments that measure:
(a) static pressure
(b) total pressure
(a) static ports
(b) pitot tubes
