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AFCS or SAS Malfunction Methods 

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Common Errors: 

  • Scanning too close to the aircraft, leading to instability. 
  • Gripping the cyclic too tightly. 
  • Making large, rapid cyclic inputs that do not translate into aircraft movement. 

Teaching Techniques: 

  • Emphasize a proper hover scan: out, over, down. A close-in scan supports precision; a scan to the horizon promotes stability. Both are essential. 
  • Reinforce the importance of fingertip pressure on the cyclic. Squeezing (over-gripping) increases pilot workload and aircraft instability. 
  • If students are over-controlling with large or abrupt cyclic movements, take the controls and demonstrate how quickly and far the cyclic can be displaced in opposing directions without moving the aircraft. Follow up with the “cyclic ring” demonstration: have one pilot hover the helicopter while the other forms a circle around the cyclic (thumb to thumb, index finger to index finger). This emphasizes the minimal control movement required to maintain a stable hover, even in moderate wind conditions. 

Notes – 

I strongly advocate for practicing AFCS-off flight under a vision-limiting device (VLD/hood), particularly while operating on the backside of the power curve. As discussed in the “Weather Flying” section of Forging Airmanship, I believe the ability to transition quickly to an effective instrument scan is foundational to Coast Guard pilot proficiency. Flying AFCS-off under a VLD accelerates scan proficiency and reinforces the ability to rapidly transition to instruments—an essential skill in scenarios like an unexpected loss of outside visual cues (e.g., IIMC). 

In addition to a hydraulics malfunction, a likely cause of a full AFCS failure is the loss of AC electrical power—either from an electrical malfunction, or intentionally, during an electrical fire when both main generators are secured, resulting in the loss of all multifunction displays (MFDs). To be better prepared for that scenario, I recommend that a portion of AFCS-off instrument flight training be conducted using only the standby instrument (ESIS), as well as practicing landings with the flying pilot’s MFDs set to anything other than the primary flight display (PFD). This approach builds the proficiency and confidence needed to respond effectively to a real-world malfunction. 

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