Chapter 8: Fundamentals of Flight Instruments

Pre-Flight Checks: Pitot-Static System

• The pitot-static system provides critical data for airspeed indicator, altimeter, and vertical speed indicator, which are essential for safe flight experience.
• A malfunction in the pitot-static system can lead to safety hazards, making thorough inspection crucial.

Pre-Flight Inspection Procedures

• Inspect the pitot tube for blockages, ice, or debris, and remove any covers.
• Ensure static ports are unobstructed by visually inspecting and gently passing a hand over them.
• Inspect the condition and security of system hoses and connections, ensuring they are intact and tight.
• Observe the instruments for signs of pitot-static system failure, such as zero readings on airspeed indicators or anomalous readings on altimeters and vertical speed indicators.

Instrument Safety Checks

• Airspeed indicator: check for stable needle at zero.
• Altimeter: set to current airport pressure setting, indicating field elevation accurately.
• Vertical speed indicator: check for neutral or zero reading during static inspection.

Detecting Pitot Tube Blockages

• Pitot tube blockages can occur due to insects, dirt, ice, or small debris, which can lead to incorrect airspeed readings or instrument failure.
• Visual inspection: inspect the pitot tube for any obstructions or blockages.
• Manual blockage test: gently run a finger along the inside of the pitot tube to feel for any anomalies or debris.
• Test equipment: anemometer testers can be used to apply pressure and suction to the pitot tube and static system to ensure they are clear and functional.

Clearing Blockages and Verification

• Clear any detected blockages using specialized tools or equipment, often handled by maintenance personnel.
• Verify the pitot tube is clear pre-flight through a final visual check.
• Include this pre-flight verification as a routine habit to ensure accurate airspeed data.

Instrument Calibration and Verification

• Calibration of instruments is a technical process that requires specialized equipment and techniques.
• Verification process:
  • Reference to maintenance records: verify the last calibration date.
  • Comparison with known values: compare readings with known field elevation or performance charts.
  • Static system test: perform a static system test using a calibrated external pressure source.
  • Professional calibration: test instruments by certified maintenance personnel using calibrated test equipment.

Pre-Flight Checks for Pitot-Static System

• The pitot-static system provides critical data for airspeed, altitude, and vertical speed indicators in every phase of flight.
• Malfunctions in the system can lead to incorrect readings, posing a safety hazard.

Importance of Pre-Flight Inspection

• Pre-flight inspection is crucial to ensure flight readiness and prevent in-flight instrument errors.
• The pitot tube is prone to blockages due to its exterior position, and visual inspection is essential to detect any debris or ice.

Steps for Pre-Flight Inspection

• Visual Inspection: Check pitot tube and static ports for blockages, damage, or tampering.
• Physical Examination: Gently tap and wiggle the pitot tube to verify security and check for debris.
• Instrument Check: Check airspeed indicator, altimeter, and vertical speed indicator for anomalies or irregularities in readings.
• Leak Check: Perform leak check on the pitot-static system if equipped with the means to do so.

Technique for Checking Pitot Tube for Blockages

• Visual Confirmation: Inspect the opening of the pitot tube for visible blockages.
• Airflow Check: Gently blow into the pitot tube or use a designated device to create airflow and listen for air escape.

Importance of Instrument Calibration

• Instrument calibration is crucial to ensure accurate readings and prevent in-flight instrument errors.
• Calibration of instruments is a technical process that requires specialized equipment and techniques.

Process for Verifying Instrument Calibration

• Reference to Maintenance Records: Verify last calibration date by reviewing aircraft maintenance records.
• Comparison with Known Values: Compare readings with known field elevation or performance charts during specific flight conditions.
• Static System Test: Perform static system test using a calibrated external pressure source.
• Professional Calibration: Test instruments by certified maintenance personnel using calibrated test equipment.

Fundamentals of Flight Instruments: Pre-Flight Checks

• The pitot-static system provides critical data for every phase of flight, and a malfunction can lead to safety hazards.
• The system directly impacts the airspeed indicator, altimeter, and vertical speed indicator.

Pre-Flight Inspection Procedures

• Visually inspect the pitot tube for debris or ice that could clog the opening.
• Ensure the pitot tube cover is removed before flight.
• Inspect static ports for obstructions and ensure they are clean.
• Check the condition and security of system hoses and connections.
• Observe the instruments themselves for signs of pitot-static system failure.

Pitot Tube Inspection

• The pitot tube plays a crucial role in measuring airspeed, which is essential for maintaining proper flight performance.
• Common culprits behind pitot tube blockages include insects, dirt, ice, and small debris.
• A meticulous pre-flight inspection to detect any blockages is necessary.

Pre-Flight Procedures for Detecting Pitot Tube Blockages

• Visual inspection: Approach the pitot tube and inspect for any obstructions.
• Hands-on check: Conduct a cover removal confirmation.
• Manual blockage test: Ensuring the pitot tube's opening is clear.

Pre-Flight Inspection of the Pitot-Static System Components

• Visual inspection: Check the pitot tube and static ports for blockages or damage.
• Physical examination: Gently tap and wiggle the pitot tube to verify it is secure and clear.
• Instrument check: Check the airspeed indicator, altimeter, and vertical speed indicator for any anomalies or irregularities.
• Leak check: Perform a leak check on the pitot-static system if the aircraft is equipped.

Technique for Checking the Pitot Tube for Blockages

• Visual confirmation: Inspect the pitot tube opening for any visible blockages.
• Airflow check: Gently blow into the pitot tube or use a designated device to create airflow and listen for the escape of air from the system.

Process for Verifying Instrument Calibration

• Reference to maintenance records: Verify the last calibration date by reviewing the aircraft's maintenance records.
• Comparison with known values: Compare the reading with a known field elevation for altimeters and with performance charts during specific flight conditions for airspeed indicators.
• Static system test: Perform a static system test using a calibrated external pressure source to simulate different altitudes and airspeeds.
• Professional calibration: Have the instruments tested by certified maintenance personnel using calibrated test equipment.

Learn about pre-flight checks and inspection procedures for a safe and confident flight. This course covers critical flight instruments and their uses.