EASA Instrument Rating theoretical foundations common mistakes
EASA Instrument Rating theoretical foundations · Understand the traps and how to avoid them.
Assuming every fly-by-wire mode retains identical protection.
A signaling architecture is mistaken for a universal control law.
What to do instead
Read the actual aircraft mode, available inputs and stated functions.
Inferring normal actuator speed from pressure alone.
Stored pressure is confused with delivered flow.
What to do instead
Check effective area, actual flow and the circuit conditions before calculating movement.
Calling a PTU an unlimited backup energy source.
Power transfer is confused with power generation.
What to do instead
Identify the available driving source and the circuits linked by the actual design.
Assuming more torque always means more governed RPM.
Torque and rotational speed are confused.
What to do instead
Apply the stated constant-speed governing condition and distinguish torque, speed and power.
Giving one oil-flow direction for every constant-speed propeller.
One installation is generalized to all propellers.
What to do instead
Use the specific propeller architecture and approved description rather than a universal hydraulic claim.
Using a summed FMS quantity as an independent confirmation of the same gauges.
A derived display is mistaken for an independent sensor.
What to do instead
Identify the input source before treating a second display as corroboration.
Opening a generic crossfeed to prove or correct every imbalance.
Engine feeding and tank transfer are treated as identical functions.
What to do instead
Use the actual fuel diagram and approved procedure; the generic symptom does not establish one safe action.
Treating a theoretical fuel-time result as authorized endurance.
A classroom quotient is confused with required reserves and real operating conditions.
What to do instead
State the given assumptions and separately identify operational requirements not supplied.
Reading a day/hour group as a simple clock time.
The day and hour fields are merged.
What to do instead
Retain day twelve and hour fourteen as separate parts of the time group.
Treating a small dew-point spread as guaranteed existing fog.
Proximity to saturation becomes an observation not provided.
What to do instead
State the risk condition and check actual weather and further cooling.
Equating a VOR radial with aircraft heading.
Position relative to a station is confused with nose direction.
What to do instead
Identify the declared reference, radial, selected course and actual heading separately.
Calling DME distance a pure ground distance.
The vertical component is ignored.
What to do instead
Use the supplied geometric separation and calculate slant range when required.