Mnemonics and Main Memory Items | Instruments

Question 1

The mnemonic to remember blockages effects while climbing and descending for the ASI?

Answer 1

CPO = Climbing - Pitot(blocked) - Over-read

CSU = Climbing - Static(blocked) - Under-read

DPU - Descending - Pitot(blocked) - under-read

DSO - Descending - Static - Over-read

Question 2

What does the blue line on a multi-engined ASI represent?

Answer 2

Vyse, the best rate of climb with one engine inoperative

Question 3

How to remember AH pitch and roll limitations:

Answer 3

East/west the earth rolls = roll limited

North/south is like pitch axis = Pitch limited

Question 4

AH:

Pendulous Acceleration will show -

Pendulous Deceleration will show -

Erection Error during acceleration will show -

Erection error during deceleration will show -

How to remember:

Answer 4

Pendulous Acceleration will show - False right bank

Pendulous Deceleration will show - false left bank

Erection Error during acceleration will show - false pitch up

Erection error during deceleration will show - false pitch down

Acceleration normally an aircraft will pitch up, and pitch down during deceleration. Acceleration is right.

Question 5

AH turning errors:

Turning through 90°:

Turning through 180°:

Turning through 270°:

Turning through 360°:

One way to remember -

Answer 5

Turning through 90°: Under reads bank angle; Pitch error – indicating a climb

Turning through 180°: Bank angle correct; Pitch error – indicating a climb (maximum pitch up error)

Turning through 270°: Over reads bank angle; Pitch error – indicating a climb

Turning through 360°: Bank angle correct; Pitch correct

90 is lower than 270, thus 270 show excess bank and 90 under bank.

Question 6

Formula for turn radius:

Answer 6

m/s^2 / 10 x tan bank angle.

m/s = 0.5 x knots.

Diameter = radius x 2

Circumference = diameter x 3.14

Question 7

Air-driven AH gyro: kept in the vertical by

Electrical AH gyro: kept in the vertical

Answer 7

pendulous vanes/air jets

two mercury switches sending signals to torque motors

Question 8

Formula for apparent drift:

Answer 8

15 x sine of the latitude

Question 9

NH: Drift is to the

SH: Drift is to the =

Answer 9

right = clockwise (-)

left anti-clockwise (+)

Question 10

For the DI or DG to measure change of heading during a banked turn, the gyro must be maintained in

Answer 10

The aircraft’s vertical and not the true vertical

Question 11

Remembering gyro magnetic compass process:

Answer 11

FEAT

Flux - Error detector - Amplifier - Torque motor

Question 12

Remembering gyro magnetic compass process:

Answer 12

FEAT

Flux - Error detector - Amplifier - Torque motor

Question 13

Relevant to altimeter:

Using static alternate inside cabin will indicate -

Answer 13

Climb. Cabin pressure in an unpressurized aircraft is lower

Question 14

The altimeter indicates true altitude:

Answer 14

A

in standard atmosphere only

Question 15

Mach number =

Thus TAS(relevant to MN) =

LSS is directly proportional to -

using this knowledge, if OAT increases when at a constant TAS:

Or just use to CX2!

Answer 15

TAS/LSS

MN x LSS

Temperature.

Mach number decreases

Question 16

LSS reduce with -

Answer 16

Temperature

Question 17

Full Scale Deflection:

• Full scale deflection in RNAV ENR Mode =
• Full scale deflection in RNAV APP Mode =
• Full scale deflection for a VOR =
• Full scale deflection for a LLZ =
• Full scale deflection for a G/S =

Answer 17

Full Scale Deflection:

• Full scale deflection in RNAV ENR Mode = 5 NM
• Full scale deflection in RNAV APP Mode = 1.25 NM
• Full scale deflection for a VOR = 10°
• Full scale deflection for a LLZ = 2.5°
• Full scale deflection for a G/S = 0.7°

2-dot EFIS display:

• one dot in RNAV ENR = 2.5 NM (some questions only have 2NM as an option, but if 2.5NM is available, select 2.5NM)
• one dot in RNAV APP = 0.625 NM
• one dot in VOR = 5°
• one dot in ILS = 1.25° (LLZ)

5-dot EFIS display:

• one dot is 1 NM in RNAV ENR (full scale = 5 dots = 5 NM)
• one dot is 0.25 NM in RNAV APP (full scale = 5 dots = 1.25NM)
• one dot is 2° in VOR
• one dot is 0.5° in ILS (LLZ)

Question 18

A leak in the pitot total pressure line of a non-pressurized aircraft to an airspeed indicator would cause it to:

Answer 18

under-read.

The mnemonic CPO CUS DPU DPO only applies to blocked line(static or dynamic)

Question 19

When an alternate static source is fed from within the cabin, it results in the static pressure sensed being:

Answer 19

lower than ambient due to aerodynamic suction

Question 20

When the alternate static source pressure is used, vented in the cabin(lower pressure), the following instrument indications are observed:

1. The altimeter indicates -
2. The ASI indicates an airspeed -
3. The VSI shows a momentary -

Answer 20

1. The altimeter indicates a slightly higher altitude than actual
2. The ASI indicates an airspeed greater than the actual airspeed
3. The VSI shows a momentary climb and then stabilizes if the altitude is held constant

Question 21

Mnemonic to remeber IAS, CAS, EAS and TAS relationship -

Answer 21

ICET PCD.

IAS + Position/instrument error = CAS

CAS + Compressibility error = EAS

EAS + density error = TAS

Question 22

In a standard atmosphere and at the sea level, the equivalent airspeed (EAS) is(relevant to TAS):

Answer 22

equal to the TAS

Question 23

During a descent at a constant calibrated airspeed (CAS) below the tropopause in ISA conditions, what happens to the TAS, MN, LSS and EAS respectively:

During a descent at a constant Mach number below the tropopause in ISA conditions, what happens to IAS and TAS respectively:

Answer 23

TAS decrease, MN decrease and speed of sound increase and EAS increase

TAS increase and IAS increase

Question 24

The indicated Mach number is independent of:

Answer 24

temperature

Question 25

Relevant to mach number:

TAS =

Answer 25

MN x LSS

Question 26

Mach number is independent of -

LSS is directly proportional to -

Answer 26

temperature

Temperature

Question 27

Considering an airspeed indicator, a second striped needle, if installed, indicates:

The velocity maximum operating (VMO) is a speed expressed in:

Answer 27

VMO

CAS or EAS

Question 28

At a given altitude, the hysteresis error of an altimeter varies substantially with the:

Answer 28

time passed at this altitude

Question 29

A compass made for the NH, the CG will be located -

Answer 29

On the southern side of the needle. For SH the opposite applies

Question 30

The direct reading magnetic compass is made aperiodic (dead beat) by:

Answer 30

keeping the magnetic assembly mass close to the compass point and by using damping wires

Question 31

Magnetic compass turning error mnemonic:

North -

South -

Answer 31

UNOS for north

ONUS for South.

UNOS is north because the first letter is “up”, NH is up from SH

Question 32

At the magnetic equator, when accelerating after take off on heading West, a direct reading pivot suspended compass:

Answer 32

indicates the correct heading