AutopilotNavigation — Instrumentation — DGCA CPL practice questions

All 6 questions — Autopilot

Navigation — Instrumentation · DGCA CPL. The correct option is marked on each.

1. Q1. What is the approximate reaction time of an autopilot to detect and correct a disturbance compared to a human pilot?

   • A.Human pilot: 50 ms; Autopilot: 200 ms
   • B.Human pilot: 200 ms; Autopilot: 50 ms✓
   • C.Human pilot: 500 ms; Autopilot: 100 ms
   • D.Both respond in approximately 100 ms

   Why: A human pilot takes approximately 200 milliseconds (1/5 of a second) to detect a change in attitude, then suffers further delay deciding which control to apply. An autopilot detects and applies the required correction in approximately 50 milliseconds . See Section 1 . — 200 ms (human) and 50 ms (autopilot) are specific book values — commit them to memory.

2. Q2. For single pilot IFR operations, what is the minimum autopilot requirement under EU-OPS?

   • A.Single axis (roll only)
   • B.Two axis with altitude hold and heading mode✓
   • C.Three axis with ILS coupling
   • D.Any autopilot capable of glide slope capture

   Why: An operator shall not conduct single pilot IFR operations unless the aeroplane is equipped with an autopilot with at least ALTITUDE HOLD and HEADING MODE — meaning at least a two-axis autopilot (roll and pitch). See Section 6 . — The regulation specifically names ALTITUDE HOLD and HEADING MODE — two functions that together make a two-axis requirement.

3. Q3. In the context of autopilot control, what is the difference between a parallel and series actuator?

   • A.Parallel actuators use hydraulic power; series actuators use electric power
   • B.Parallel actuators also move the control stick; series actuators move the control surface without moving the stick✓
   • C.Parallel actuators are used for roll only; series actuators for pitch only
   • D.Series actuators have higher authority than parallel actuators

   Why: A parallel actuator produces movement of the control surface AND provides feedback to the control stick (the stick moves when the A/P controls). A series actuator produces control surface movement without moving the stick. See Section 7 . — On aircraft with parallel actuators, an unaware pilot may be startled to see the control column moving on its own during autopilot operation.

4. Q4. When tracking a VOR with the autopilot and entering the cone of confusion overhead the beacon, the A/P roll channel:

   • A.Disconnects completely and the crew must fly manually through the cone
   • B.De-couples from the VOR and goes into Heading Hold on the drift-corrected heading✓
   • C.Goes into Heading Select mode and turns toward the next waypoint
   • D.Continues to track the VOR signal despite reduced accuracy

   Why: At a point before the cone of confusion, 'over station sensing' circuits cut off VOR signals. The roll channel automatically de-couples from the radio beam and flies the drift-corrected heading that existed at de-coupling — this is Heading Hold, not Heading Mode/Select. After a set period, it reverts to VOR mode. See Section 13 . — The Heading Hold vs Heading Select distinction is a classic trick question in DGCA exams.

5. Q5. V NAV path descent automatically disengages if flaps are extended beyond:

   • A.5°
   • B.10°
   • C.15°✓
   • D.25°

   Why: V NAV path descent disengages when flaps are extended beyond 15° . This is because the approach configuration changes the aircraft's drag and performance profile significantly enough that VNAV path control is no longer appropriate. See Section 14 . — The 15° flap threshold for VNAV disconnect is an aircraft-specific value (737-400). It represents the transition from clean/approach configuration to significant drag-producing flap.

6. Q6. What is the key operational difference between Control Wheel Steering (CWS) and Touch Control Steering (TCS)?

   • A.CWS disengages the autopilot while TCS keeps it engaged
   • B.CWS keeps the autopilot engaged and responds to stick force; TCS disengages the A/P channels while the button is held✓
   • C.CWS is only for roll; TCS is only for pitch
   • D.TCS requires a higher control force than CWS to operate

   Why: CWS keeps the autopilot engaged — the A/P manoeuvres the aircraft in response to control pressure. TCS disengages the appropriate A/P channels and servomotors while the button is held, allowing the pilot to fly manually; on release, the A/P re-engages at the new attitude. See Section 15 . — CWS = "steer through the A/P" (like power steering). TCS = "temporarily take over, then hand back."