Flight Instruments Quiz Flashcards
You check the flight instruments while taxiing and find the VSI indicates a descent of 100 fpm. In this case you,
may take off and can use the -100 fpm as a 0 indication
What effect will a change in wind direction have upon maintaining a 3* glide slope at a constant true airspeed.
When ground speed increases, rate of descent must increase
As a rule of thumb, altitude corrections of less than 100feet should be corrected by using a:
half bar width on the attitude indicator
If both the ram air input and drain hole input of the pitot system were blocked, what airspeed indication would be expected?
No variation in indicated airspeed in level flight even if large power changes are made.
What does the miniature aircraft on the turn coordinator display?
Rate of roll and rate of turn
What are the definitions for the different types of airspeeds?
Indicated: Read directly from the airspeed indicator
Calibrated: Indicated corrected for installation error
True: Actual speed through the air
Ground Speed: Speed over the ground
How does the altimeter work?
The sensitive element in a sensitive altimeter is a stack of evacuated, corrugated bronze aneroid capsules. The air pressure acting on these aneroids tries to compress them against their natural springiness, which tries to expand them. The result is that their thickness changes as the air pressure changes. Stacking several aneroids increases the dimension change as the pressure varies over the usable range of the instrument.
How does the Airspeed indicator work?
The mechanism of the ASI in Figure 5-11 consists of a thin, corrugated phosphor bronze aneroid, or diaphragm, that receives its pressure from the pitot tube. The instrument case is sealed and connected to the static ports. As the pitot pressure increases or the static pressure decreases, the diaphragm expands. This dimensional change is measured by a rocking shaft and a set of gears that drives a pointer across the instrument dial.
If the static port becomes blocked, which instrument(s) are affected and how?
Airspeed indicator – continues to operate, but inaccurate; acts like an altimeter
Altimeter – Freezes at altitude where blockage occurred
VSI – Stays at 0
Which instruments are gyroscopic?
Attitude indicator, Heading indicator, and Turn Coordinator
How does the attitude indicator work?
Its operating mechanism is a small brass wheel with a vertical spin axis, spun at a high speed by either a stream of air impinging on buckets cut into its periphery, or by an electric motor. The gyro is mounted in a double gimbal, which allows the aircraft to pitch and roll about the gyro as it remains fixed in space. A horizon disk is attached to the gimbals so it remains in the same plane as the gyro, and the aircraft pitches and rolls about it
For each of the instruments below please describe the items verified on the Flight Deck Check (Instrument Cockpit Check)
a. Airspeed Indicator: read 0
b. Attitude Indicator: Up and erect within 5 minutes if vacuum, 3 minutes if
electrically driven gyro, otherwise noted in avionics documents
c. Altimeter: within 75ft of airport elevation when barometric setting entered
d. Turn Coordinator: During taxi turns, miniature airplane and slip/skid should have
proper indications (wing in, ball out)
e. Directional Gyro: (Heading indicator) Allow 5 minutes after starting engines for the gyro to spin up. Before taxiing, or while taxiing straight, set the heading indicator to correspond with the magnetic compass heading. A slaved gyrocompass should be checked for slaving action and its indications compared with those of the magnetic compass. If an electronic flight instrument system is installed, consult the flight manual for proper procedures
f. Vertical Speed Indicator: Read 0, if not – note 0 mark
g. Magnetic Compass: Full of fluid, free movement of compass card, compare against known heading (runway marking
