đŠ️A Machmeter is an aircraft pitot-static system flight instrument that shows the ratio of the true airspeed to the speed of sound, a dimensionless quantity called Mach number. This is shown on a Machmeter as a decimal fraction.
đŠ️As an aircraft in transonic flight approaches the speed of sound, it first reaches its critical mach number, where air flowing over low-pressure areas of its surface locally reaches the speed of sound, forming shock waves.
đŠ️The indicated airspeed for this condition changes with ambient temperature, which in turn changes with altitude. Therefore, indicated airspeed is not entirely adequate to warn the pilot of the impending problems. Mach number is more useful, and fighters are limited to a maximum operating Mach number.
đŠ️An aircraft flying at the speed of sound is flying at a Mach number of one, expressed as Mach 1.
đŠ️Mach meter is a compound air data instrument which has two sensors.
đŠ️The air speed capsule measures the pressure difference between the pitot and static pressure.
đŠ️It expands/ contracts as airspeed increases/ decreases. The movement of the capsule is transferred by air speed link to the main shaft, causing it to rotate and move ratio arm.
đŠ️The expansion and contraction of altitude capsule is also transferred to the ratio arm.
đŠ️The position of ratio arm depends upon both pitot excess and static pressure.
đŠ️The movement of ratio arm controls ranging arm which through linkages turns the pointer displaying corresponding Mach number.
đŠ️An increase in altitude and/or air speed results in a display of higher Mach number.
➡️Subscribe us for more aircraft knowledge and aircraft fact⬅️
➡️Do Share with your Friends⬅️
Comments
Post a Comment