A DPE’s Take on Deciphering the ACS: Emergency Descent

A DPE’s Take on Deciphering the ACS: Emergency Descent

When I begin my briefings with applicants, I often begin with stating that the ACS is the standard. Sometimes I have students and flight schools asking me how I want to see certain maneuvers, and I always point them to FAA published materials to answer their question. There is no certain “way” that I want to see a maneuver – if the maneuver is compliant with the ACS and the applicant demonstrates proficiency, risk management, and good judgement – then it is satisfactory. However, there are times where the ACS does leave a lot to the discretion of the applicant and/or examiner, so I figured I’d discuss the process for determining how to complete a task.

The question came up on a group on social media where a student was asking the community how to perform the Emergency Descent maneuver (PA.IX.A). The student began with saying that his instructor had told him to accelerate to VNE (never exceed speed). He then asked if this was how you were supposed to complete the maneuver, to which I would say as a DPE “it depends.” The ACS task states that the applicant demonstrates the ability to: 

  • • PA.IX.A.S1 Clear the area. 
  • • PA.IX.A.S2 Establish and maintain the appropriate airspeed and configuration appropriate to the scenario specified by the evaluator and as covered in POH/AFM for the emergency descent. 
  • • PA.IX.A.S3 Maintain orientation, divide attention appropriately, and plan and execute a smooth recovery. 
  • • PA.IX.A.S4 Use bank angle between 30° and 45° to maintain positive load factors during the descent. 
  • • PA.IX.A.S5 Maintain appropriate airspeed +0/-10 knots, and level off at a specified altitude ±100 feet. 
  • • PA.IX.A.S6 Complete the appropriate checklist.

The emphasis on “how” really falls under skills section 2, where the ACS directs the applicant to: “Establish and maintain the appropriate airspeed and configuration appropriate to the scenario specified by the evaluator and as covered in POH/AFM for the emergency descent.” One important thing to note is that the evaluator should be providing a scenario which requires the use of this maneuver. If the examiner doesn’t specify, then it might be prudent of the applicant to ask since the emergency may impact the configuration chosen by the applicant. That being said, many small general aviation airplanes do not have a specific emergency descent procedure detailed in the POH/AFM. So the question becomes, how do we perform the maneuver without direct guidance from the manufacturer? 

While not an all-encompassing list, the accomplishment of any task generally falls within the following guidance or priority: 

  1. Airplane manufacturer specifies through the POH/AFM.
  2. Approved procedures by the operating certificate holder (such as a 121 or 135 operator, or 142 training center approved syllabus).
  3. Recommended procedures through FAA published material (Advisory Circular, Airplane Flying Handbook, etc).

When we don’t have options 1 or 2, we then must revert to option 3. There are several resources for the maneuver through FAA published material.

The Airplane Flying Handbook, Chapter 17, discusses the maneuver: “Emergency descent training should be performed as recommended by the manufacturer, including the configuration and airspeeds. Except when prohibited by the manufacturer, the power should be reduced to idle, and the propeller control (if equipped) should be placed in the low pitch (or high revolutions per minute (rpm)) position… The pilot should not allow the airplane’s airspeed to pass the never-exceed speed (VNE), the maximum landing gear extended speed (VLE), or the maximum flap extended speed (VFE), as applicable. In the case of an engine fire, a high airspeed descent could blow out the fire. However, the weakening of the airplane structure is a major concern and descent at low airspeed would place less stress on the airplane. If the descent is conducted in turbulent conditions, the pilot must also comply with the design maneuvering speed (VA) limitations. The descent should be made at the maximum allowable airspeed consistent with the procedure used. This provides increased drag and, therefore, the loss of altitude as quickly as possible. The recovery from an emergency descent should be initiated at a high enough altitude to ensure a safe recovery back to level flight or a precautionary landing.”

Advisory circular AC 25-20 also discusses emergency descent procedures specific to pressurized aircraft. While pressurized aircraft operations are generally not evaluated through this maneuver on a private pilot practical exam, it’s important that an applicant understands WHY we would use an emergency descent procedure and can accomplish it based on the scenario presented by the evaluator. As mentioned above, turbulence and type of emergency (such as a fire) can and will dictate the speeds and configuration to use.

So the question still persists: what speed and configuration to use when we don’t have manufacturer’s guidance?

Many students often don’t read the foreword and after words of the ACS. In the very first page after the table of contents, the ACS goes on to say:

“Safe operations in today’s National Airspace System (NAS) require integration of aeronautical knowledge, risk management, and flight proficiency standards…The ACS integrates the elements of knowledge, risk management, and skill listed in 14 CFR part 61 for each airman certificate or rating…The flight portion of the practical test requires the applicant to demonstrate knowledge, risk management, flight proficiency, and operational skill in accordance with the ACS.”

At the end of the ACS, there is a paragraph on Aeronautical Decision-Making:

“Throughout the practical test, the evaluator must assess the applicant’s ability to use sound aeronautical decision-making procedures in order to identify hazards and mitigate risk. The evaluator must accomplish this requirement by reference to the risk management elements of the given Task(s), and by developing scenarios that incorporate and combine Tasks appropriate to assessing the applicant’s risk management in making safe aeronautical decisions.”

As an examiner, I’m looking for mastery of the ACS task through evaluation. Risk management and decision making is paramount to the successful execution of any task, and I look for that in every maneuver. If an applicant chooses a configuration and airspeed that is appropriate for the scenario according to the manufacturer, approved course/operation, or FAA published guidance; then that maneuver will be satisfactory as long as all of the elements of the ACS task are met.


Sarah is currently a FAA Safety Team Lead Representative, NAFI Master Instructor, Gold Seal flight instructor, and 737 pilot for a Major U.S. airline. Sarah holds an ATP, CFI, CFII, MEI and has flown over 7300 hours. She holds a pilot license in 4 different countries (USA, Canada, Belize and Iceland – EASA) and has flown over 150 different types of airplanes in 25 different countries including oceanic crossings in small aircraft. Since aviation for work isn’t enough, she also lives in a hangar home on the west side of Houston! Although much of her flying is now professional in nature, she enjoys flying her Super Cub, Patches, on her days off. As a regular attendee of Oshkosh and local fly-ins, she enjoys the company and camaraderie that general aviation brings and is passionate about aviation safety and flight training.

One thought on “A DPE’s Take on Deciphering the ACS: Emergency Descent

  1. Great answers to the questions that came up in the post. As a DPE for the last 18 years, I’ve seen a lot of different responses to different scenarios. As long as the pilots actions are reasonable, safe and meet the ACS requirements, it’s a pass.

    Liked by 1 person

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