100+ Free SACAA AME Instruments Practice Questions

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Sample SACAA AME Instruments Practice Questions

Try these sample questions to test your SACAA AME Instruments exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1In a basic aircraft pitot-static system, what pressure component is measured exclusively by the pitot tube opening during unaccelerated level flight?

A.Static pressure only

B.Total pressure (static pressure plus dynamic pressure)

C.Dynamic pressure only

D.Differential cabin pressure

Explanation: The pitot tube is oriented parallel to the relative airflow and senses total pressure (also referred to as ram pressure or pitot pressure), which is the sum of ambient static pressure and dynamic pressure resulting from the aircraft's motion.

2Where are static pressure ports typically mounted on an aircraft fuselage to minimize aerodynamic position error?

A.In the engine intake plenum where airflow velocity is highest

B.Flush with the skin on both sides of the fuselage in an area of undisturbed airflow

C.Directly behind the propeller arc on the upper nose cowling

D.Inside the unpressurized wheel well bay

Explanation: Static ports are mounted flush on opposite sides of the fuselage in locations where air pressure is least affected by aerodynamic disturbances. Dual balanced static ports connected in parallel cancel out pressure errors caused by aircraft sideslip or yaw.

3If the pitot tube ram air inlet becomes completely blocked by ice while its drain hole remains OPEN, how will the Airspeed Indicator (ASI) react during a climb?

A.The ASI reading will drop to zero speed.

B.The ASI will over-read, behaving like an altimeter.

C.The ASI reading will freeze at the speed held prior to blockage.

D.The ASI reading will fluctuate wildly around Vne.

Explanation: When the ram inlet is blocked while the drain hole remains open, trapped air inside the pitot tube escapes through the open drain hole into the static system or atmosphere. The pressure in the ASI diaphragm drops to static pressure, causing the pressure differential across the diaphragm to become zero, so the ASI reads zero.

4What happens to the Airspeed Indicator (ASI) indication if BOTH the pitot tube ram inlet and drain hole are completely frozen shut during an aircraft descent?

A.The ASI will under-read (indicate lower than true airspeed).

B.The ASI will over-read (indicate higher than true airspeed).

C.The ASI pointer will immediately fall to zero.

D.The ASI pointer will lock firmly at the maximum scale reading.

Explanation: With both inlet and drain blocked, total pressure trapped inside the ASI diaphragm remains constant. As the aircraft descends, ambient static pressure inside the instrument case increases. The increasing case pressure compresses the diaphragm, reducing the indicated pressure difference and causing the ASI to under-read.

5If the primary static line becomes completely blocked during flight, how will the Altimeter, Vertical Speed Indicator (VSI), and Airspeed Indicator (ASI) behave during a climb?

A.Altimeter freezes; VSI reads zero; ASI under-reads.

B.Altimeter over-reads; VSI indicates maximum climb rate; ASI over-reads.

C.Altimeter freezes; VSI indicates maximum descent rate; ASI reads zero.

D.Altimeter under-reads; VSI freezes at last rate; ASI functions normally.

Explanation: With a blocked static line, trapped static pressure stays constant. The altimeter freezes at the altitude where blockage occurred. The VSI calibrated leak equalizes pressure across its diaphragm, returning the pointer to zero. As the aircraft climbs, ambient total pressure drops while trapped static pressure inside the ASI case stays high, causing the ASI to under-read.

6When an unpressurized aircraft switch is selected to the alternate static source located inside the cockpit, what indication changes occur due to cockpit pressure characteristics?

A.Altimeter reads lower; ASI reads lower; VSI momentarily indicates a descent.

B.Altimeter reads higher; ASI reads higher; VSI momentarily indicates a climb.

C.Altimeter reads higher; ASI reads lower; VSI momentarily indicates a descent.

D.No change occurs because cockpit air pressure matches atmospheric pressure exactly.

Explanation: Airflow over the cabin structure creates a slight suction, making cockpit pressure slightly lower than ambient outside static pressure. Selecting alternate static reduces static reference pressure inside the instrument cases, causing the altimeter to indicate higher, ASI to indicate higher, and VSI to show a temporary climb pulse.

7What is the standard pressure reference value displayed in the Kollsman window of an altimeter when set to Standard Altimeter Setting (QNE)?

A.1013.25 hPa or 29.92 inHg

B.1000.00 hPa or 29.00 inHg

C.1023.25 hPa or 30.12 inHg

D.992.50 hPa or 28.92 inHg

Explanation: Standard sea level pressure per the International Standard Atmosphere (ISA) is 1013.25 hectopascals (hPa / millibars) or 29.92 inches of mercury (inHg), which is QNE.

8An aircraft is parked at an aerodrome elevation of 4,500 feet. The local QNH is 1023 hPa. If the altimeter sub-scale is adjusted from 1023 hPa to standard 1013.25 hPa (QNE), what is the calculated Pressure Altitude? (Use standard rule: 1 hPa = 30 ft)

A.4,793 feet

B.4,207 feet

C.4,500 feet

D.5,100 feet

Explanation: Pressure Altitude = Field Elevation + (1013.25 - QNH) * 30 ft/hPa. Here, (1013.25 - 1023) = -9.75 hPa. Distance adjustment = -9.75 * 30 = -292.5 ft. Pressure Altitude = 4500 - 292.5 = 4207.5 feet (approx 4,207 ft).

9An aircraft is at an airfield elevated at 2,000 feet MSL. The current altimeter setting is 29.42 inHg. What is the calculated Pressure Altitude? (Use standard rate: 1 inHg = 1,000 ft)

A.2,500 feet

B.1,500 feet

C.2,000 feet

D.3,000 feet

Explanation: Pressure Altitude = Field Elevation + (29.92 - Local Altimeter Setting) * 1,000 ft/inHg. Pressure Altitude = 2,000 + (29.92 - 29.42) * 1,000 = 2,000 + (0.50 * 1,000) = 2,500 feet.

10Inside a conventional mechanical Airspeed Indicator, how are pitot and static pressures routed?

A.Pitot pressure is applied to the inside of the capsule; static pressure is applied inside the instrument case.

B.Static pressure is applied to the inside of the capsule; pitot pressure is applied inside the instrument case.

C.Both pitot and static pressures are applied into separate concentric aneroid capsules.

D.Pitot pressure drives a bimetallic strip; static pressure drives a hairspring gear assembly.

Explanation: In an ASI, total (pitot) pressure is piped directly inside the flexible metallic diaphragm/capsule, while static pressure fills the airtight instrument case surrounding the capsule. The expansion of the capsule represents dynamic pressure (Pitot - Static).

About the SACAA AME Instruments Exam

The SACAA AME Instruments examination tests pitot-static systems (leak testing, altimeter calibration, ASI, VSI), gyroscopic instruments (rigidity, precession, AHRS, flux valves), engine indication systems (EGT/EPR/torque), compass swings, and FDR/CVR flight recorder maintenance.

Assessment

Question count not published by the exam provider

Time Limit

75 minutes

Passing Score

75%

Exam Fee

~R425–R450 per subject (confirm current SACAA Part 187 fee) (South African Civil Aviation Authority (SACAA))

SACAA AME Instruments Exam Content Outline

25%

Pitot-Static Systems & Pressure Instruments

Pitot tubes, static ports, altimeters, airspeed indicators (ASI), vertical speed indicators (VSI), Machmeters, and pitot-static leak testing.

25%

Gyroscopic Instruments & AHRS

Rigidity in space, precession, vacuum/electric gyros, attitude indicator, directional gyro, turn coordinator, flux valves, and Attitude Heading Reference Systems (AHRS).

20%

Engine & Systems Indicating Instruments

Tachometers, pressure/temperature gauges, fuel flow transmitters, exhaust gas temperature (EGT), engine pressure ratio (EPR), and torque indicators.

15%

Direct & Remote Reading Compasses

Direct reading magnetic compasses, deviation, variation, compass swing procedures, remote indicating compasses, and flux gate magnetometers.

15%

FDR, CVR & Flight Data Monitoring

Flight Data Recorders (FDR), Cockpit Voice Recorders (CVR), underwater locating beacons (ULB), pitot-static calibration, and instrument inspection rules.

How to Pass the SACAA AME Instruments Exam

What You Need to Know

Passing score: 75%
Assessment: Question count not published by the exam provider
Time limit: 75 minutes
Exam fee: ~R425–R450 per subject (confirm current SACAA Part 187 fee)

Keys to Passing

Work through all 100 available questions
Review every answer and explanation
Track weak areas and revisit them
Use our AI tutor for tough concepts

SACAA AME Instruments Study Tips from Top Performers

1Understand pitot-static failures: blocked pitot tube makes ASI act like an altimeter in climb/descent.

2Memorise gyro principles: rigidity in space depends on rotor mass, radius, and rotational speed.

3Review thermocouple operating principles (Seebeck effect) for EGT and CHT temperature measurement.

4Know FDR and CVR recording durations and underwater locator beacon (ULB) frequency (37.5 kHz).

Frequently Asked Questions

What is the pass mark for SACAA AME Instruments?

The pass mark is 75%, tested centrally via SACAA PEXO multiple-choice exam.

What pitot-static tests are covered?

Altimeter scale error, static system leak test (maximum allowable leakage over 1 minute), pitot heater current draw, and alternate static source operation.

Does this exam cover compass swings?

Yes, compass swing procedures, degaussing, compensating magnets (N-S and E-W adjustments), and residual deviation card recording.

100+ Free SACAA AME Instruments Practice Questions

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