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courses:206a:instruments

206A - Basic Instrument Flying

Pre-Lesson Reading

  • Instrument Flying Handbook Ch. 1 (Human Factors)
  • Instrument Flying Handbook Ch. 3 (Flight Instruments)
  • Instrument Flying Handbook Ch. 4 (Airplane Attitude Instrument Flying)

Standby Instruments & Principles

C172 G1000

  • Attitude Indicator (Vacuum)
  • Altimeter (Static)
  • Airspeed Indicator (Pitot/Static)

PA28R

  • Fully integrated standby instrument (AHRS)

Compass Principles

Deviation: caused by local magnetic fields within the aircraft. Deviation error is different on each heading

Deviation card shows what the mechanics are unable to correct/adjust.

Magnetic Dip: indication errors caused by an unbalanced compass

Teter-totter balance analogy–@magnetic equator north and south forces are balanced. Increase latitude, north pole is pulling down more than south pole.

Above 60° latitude, compass is unusable—too much dip

Basic Instrument Scan

The “Music Scan” on steam vs. G1000

Fundamental Skills of Instrument Flying (IFH p.4-5)

  1. Instrument Cross-Check
  2. Instrument Interpretation
  3. Aircraft Control

Spatial Disorientation & In-Flight Illusions

Unusual Attitude Recovery

(See Instrument Flying Handbook p.5-31/p.100)

Nose Low v. Nose High

Common Errors

  1. Failure to keep the airplane properly trimmed. A cockpit interruption when you are holding pressures can easily lead to inadvertent entry into unusual attitudes.
  2. Disorganized cockpit. Hunting for charts, logs, computers, etc., can seriously detract your attention from the instruments.
  3. Slow cross-check and fixations. Your impulse is to stop and stare when you note an instrument discrepancy unless you have trained enough to develop the skill required for immediate recognition.

Safe Operations Under IFR

Flight Fundamentals

Straight & Level

Primary Bank: Heading Indicator

Primary Pitch: Altimeter

Climbs

Constant Airspeed Climb

Primary Bank: Heading Indicator

Primary Pitch: Airspeed Indicator

Constant Rate Climb

Primary Pitch: VSI

Turns

To a heading - primary bank: DG

Standard rate - primary bank: Turn Coordinator

Glide (Emergency)

Primary Pitch: Airspeed Indicator

Primary Bank: Heading Indicator (or Compass if vac inop)

Magnetic Compass Turns

When making a turn from a northerly heading, the compass briefly gives an indication of a turn in the opposite direction. When making a turn from the south, it gives an indication of a turn in the correct direction but at a faster rate.

Timed Turns

Standard Rate Turns: 3°heading/second: 2 minutes for 360° turn.

Bank angle required: Standard rate turns: 15% of TAS or ~20% IAS (easier to calculate)

Vertical S Maneuvers

This maneuver is a series of climbs and descents at a definite indicated rate.

  1. Climbing or descending airspeed should be established prior to entry.
  2. During the reversal of vertical direction, lead the altitude 40 to 60 feet in descents and 20 to 30 feet in climbs.
  3. Change the altitude 500 feet, 400 feet, 300 feet, then 200 feet, returning to the original altitude each time. After the 200-foot altitude change, return to the original altitude and level-off at climbing or descending airspeed (low cruise).
  4. Performing the Vertical S.
    1. From an exact altitude and climbing or descending airspeed, adjust power and pitch attitude to enter a climb or descent.
    2. As the power is adjusted in the entry, the airspeed indicator becomes primary for pitch.
    3. As the vertical speed approaches 500 feet per minute, the vertical-speed indicator becomes primary for pitch and remains so until the reversal of the vertical direction is started. As the vertical speed reaches 500 feet per minute, the airspeed indicator again becomes the primary instrument for power.
    4. As the reversal of the vertical direction is started, the airspeed indicator becomes primary for pitch and remains so until the vertical speed approaches the desired rate of 500 feet per minute.
    5. Stress the importance of trim and cross-check.
courses/206a/instruments.txt · Last modified: 2018/11/13 18:33 by evan