All procedures here are GENERALIZED for learning.
Fly the maneuver in accordance with the Pilot Operating Handbook (POH)
and/or current Standard Operating Procedures (SOPs)
Primary and Supporting Method:
- For any maneuver of flight condition, the pitch, bank, and power control requirements are most clearly indicated by certain key instruments
- These are your primary instruments while those that back up these indications will be supporting
- Pitch Instruments:
- Attitude indicator
- Altimeter
- Airspeed Indicator
- Vertical Speed Indicator
- Bank Instruments:
- Attitude Indicator
- Heading Indicator
- Magnetic Compass
- Turn Coordinator
- Power Instruments:
- Airspeed Indicator
- Engine Instruments
- Manifold Pressure
- Tachometer
- Engine Pressure Radio (EPR)
Skills Involved:
- Cross Checking:
- Human error, instrument error, and atmospheric changes make it impossible to establish an attitude and keep performance constant
- Cross-checking is the continuous scanning of flight instruments to maintain desired attitude and performance
- Selected Radial Cross-Check:
- 80-90% of scan is focused on attitude indicator
- Scan begins with attitude and branches out to various other instruments but scan always return to attitude before checking the next instrument branches will depend on maneuver
- Rectangular Cross-Check:
- Scan moves in a clockwise or counter clockwise direction around the basic six pack, thus creating a rectangular pattern
- Gives equal weight to each instrument
- Can lengthen time between checking instruments critical for maneuver being performed
- Common Cross-Check:
- Common cross-check for a beginner is rapidly looking at different instruments without knowing why or what they are looking for
- With experience the common cross-check becomes habit, you look at the instruments needed for the given situation, you know what to look for and how long to look
- Instrument Interpretation:
- Understanding the information provided by cross-checking
- Requires through study and analysis
- An understanding of both construction and operating principles is necessary
- The more a pilot knows about the instruments in his or her plane the better they will be able to understand the information being given to them
- By knowing trends and limitations of instruments a pilot will know what other instruments to cross-check to get the complete picture
- Such things as knowing what pitch attitudes to use for a given rate of climb or what power settings will give an approximate airspeed will reduce pilots workload
- Aircraft Control:
- Taking the instrument information that has been interpreted and making physical adjustments to flight controls in response
- When using instruments instead of outside references the control inputs are the same, but must be smooth and precise
- There are four components to aircraft control:
- Pitch Control:
- Controlling the rotation of the aircraft around the lateral axis by movement of the elevators in response to instrument interpretation
- Bank Control:
- Controlling angle made by the wing and the horizon, after interpreting appropriate instruments movement of the ailerons to roll the aircraft about its longitudinal axis
- Power Control:
- Interpretation indicates need for adjustment in thrust
- Trim Control:
- Trim removes control pressure once desired attitude is attained
- Improper trim will cause a need for constant force need on the controls, this adds distraction and leads to abrupt and unintentional attitude changes
Airman Certification Standards:
Common Errors:
- Fixation:
- Tendency to stare a one instrument and negate the rest
- If off altitude, you may stare at altimeter until desired altitude is regained
- While a change in bank is occurring tendency will be to stare at heading indicator until reaching desired heading, this will negate all power and pitch instruments
- Omission:
- Leaving a particular instrument out of scan
- In a climb you may reference altitude, airspeed, and vertical speed but inadvertently omit altimeter
- Emphasis
- Checking one or a few instruments more readily than the rest
- Generally the case with less experienced pilots because they may not understand an instrument fully, and tendency is to rely on what you know
- Students may be able to hold altitude well by use of altimeter but can not do so with only using the attitude indicator
- With low time pilots there is a tendency to either not believe instruments because they do not agree with what they "feel" is right or the pilot will omit instrument errors
- With more experienced pilots, a common interpretation error is the tendency to carry over knowledge from one plane to the next
- Example: flying a low performance plane like a high performance one
References:
- Instrument Flying Handbook