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Safety Recommendation Details

Safety Recommendation A-82-145
Details
Synopsis: ON DECEMBER 31, 1981, SUN WEST AIRLINES, INC., FLIGHT 104, N41070, A PIPER PA-31-350 CRASHED DURING AN ATTEMPTED MISSED APPROACH AT DURANGO, COLORADO. THE PILOT HAD EXECUTED A NONPRECISION VOR-DME APPROACH AT RUNWAY 2 AT DURANGO-LAPLATA COUNTY AIRPORT IN WEATHER CONDITIONS AT OR SLIGHTLY BELOW THE LANDING MINIMUMS FOR THE APPROACH. THE AIRPLANE DESCENDED AND CRASHED ABOUT 3,250 FEET FROM THE MISSED APPROACH POINT. THE PILOT AND THREE PASSENGERS WERE KILLED AND TWO PASSENGERS WERE SERIOUSLY INJURED AS A RESULT OF THE ACCIDENT.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: AMEND 14 CFR PART 135 TO REQUIRE HUMAN ENGINEERING EVALUATIONS OF THE AIRPLANE, INCLUDING THE OPERATING ENVIRONMENT AS WELL AS ITS CONTROLS AND DISPLAYS, AS A BASIS FOR CERTIFICATION OF SINGLE-PILOT, MULTIENGINE IFR OPERATIONS.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Alternate Action
Mode: Aviation
Location: Durango, CO, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA82AA007
Accident Reports: Sun West Airlines Flight 104, Piper PA-31-350 (T-1020), N41070
Report #: AAR-82-13
Accident Date: 12/31/1981
Issue Date: 11/24/1982
Date Closed: 6/3/1988
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Alternate Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 6/3/1988
Response: We are pleased to note that the FAA has revised Handbook 8430.1D to include a change in consonance with the above recommendation. Safety Recommendation A-82-145 is now classified as "Closed--Acceptable Alternate Action."

From: NTSB
To: FAA
Date: 4/14/1988
Response: We note that the FAA is in the process of revising Handbook 8430.1D to include a change in consonance with the above recommendation. We also note that since this is not expected to be completed until July 1988, the FAA will, in the interim, issue an immediate air carrier operations bulletin which will include guidance material regarding the single-pilot/autopilot instrument flight rules operations. Pending your further response, this recommendation is classified as "Open--Acceptable Data Source: NTSB Recommendations to FAA and FAA Responses Alternate Action."

From: FAA
To: NTSB
Date: 3/25/1988
Response: IN PREVIOUS CORRESPONDENCE, THE FAA STATED THAT IT DID NOT INTEND TO AMEND THE CURRENT REGULATIONS AS REQUESTED IN THIS SAFETY RECOMMENDATION. THE FAA DID, HOWEVER, STATE THAT IT WOULD ISSUE A CHANGE TO HANDBOOK 8430.1D TO ENSURE THAT APPROPRIATE INITIAL AND RECURRENT AUTOPILOT FLIGHT CHECKS ARE TAILORED TO THE "OPERATING ENVIRONMENT" IN WHICH AUTHORIZATION IS TO BE USED. THE FAA HAS NOW ISSUED THE CHANGE TO HANDBOOK 8430.1D WHICH TRANSMITS ACOB PART 135 NO. 88-1, SINGLE-PILOT/AUTOPILOT IFR OPERATIONS. I HAVE ENCLOSED A COPY OF THE CHANGE FOR THE BOARD'S INFORMATION.

From: FAA
To: NTSB
Date: 2/22/1988
Response: THE FAA IS IN THE PROCESS OF REVISING THE ENTIRE HANDBOOK 8430.1D. THIS IS A COMPLEX AND LENGTHY PROCESS THAT IS NOT EXPECTED TO BE COMPLETED UNTIL JULY 1988. INCLUDED IN THIS REVISION WILL BE THE CHANGE MENTIONED ABOVE. BECAUSE OF THE AMOUNT OF TIME IT WILL TAKE TO REVISE THE ENTIRE HANDBOOK, THE FAA HAS DECIDED TO ISSUE AN IMMEDIATE AIR CARRIER OPERATIONS BULLETIN (ACOB) WHICH WILL INCLUDE GUIDANCE MATERIAL REGARDING THE SINGLE-PILOT/AUTOPILOT INSTRUMENT FLIGHT RULES OPERATIONS. THIS ACOB SHOULD BE ISSUED WITHIN THE NEXT 60 DAYS.

From: NTSB
To: FAA
Date: 5/3/1985
Response: The Safety Board is aware of the current certification requirements for single-pilot multiengine, instrument flight rules (IFR) operations. It is the Safety Board's belief that, while the flight evaluation must include complex air traffic control procedures and a demonstration of proficiency equivalent to that required when a two-pilot crew is used, there are operating situations that could provide a higher pilot workload than those used in the certification/evaluation tests. For instance, single pilot IFR operations at uncontrolled airports can offer an overall higher pilot workload than routine air traffic control procedures at controlled airports. The Safety Board realizes that each operator has a unique set of operating conditions, i.e., terrain, airport geography, weather patterns, route lengths, and pilot skills, which make it difficult to certify a specific model aircraft for all operating situations. The Safety Board recommendation can best be served through the thorough inspection of the operator's use of the aircraft in the actual operating environment. Therefore, the Safety Board is pleased to learn that the FAA plans to provide specific instructions in Change 1 to the Air Carrier Operations Inspector's Handbook - Part 135, 8430.1D, to ensure that initial and recurrent flight checks are tailored to the operating environment in which the authorization is to be used, and that field inspectors will pay particular attention to pilot workload and provide a course of action should deficiencies be noted. When published, this amendment to the Air Carrier Operations Handbook will be accepted as complying with the intent of this recommendation. Pending review of this amendment, Safety Recommendation A-82-145 has been classified as "Open--Acceptable Alternate Action." Your efforts to respond to this Safety Recommendation are appreciated.

From: FAA
To: NTSB
Date: 3/4/1985
Response: FAA LTR: ...INTEND TO PROVIDE SPECIFIC INSTRUCTIONS IN CHANGE 1 TO THE AIR CARRIER OPERATIONS INSPECTOR'S HANDBOOK PART 135, 8430.1D, TO ENSURE THAT INITIAL AND RECURRENT AUTOPILOT FLIGHT CHECKS ARE TAILORED TO THE "OPERATING ENVIRONMENT" IN WHICH THE AUTHORIZATION IS TO BE USED. THIS CHANGE WILL ALSO ASK FIELD INSPECTORS TO PAY PARTICULAR ATTENTION TO AIRCRAFT CONTROLS AND DISPLAYS, INTERFACE WITH THE PILOT DURING ANY REQUIRED MANEUVERS, AND PROVIDE A COURSE OF ACTION SHOULD DEFICIENCIES BE NOTED.

From: NTSB
To: FAA
Date: 9/5/1984
Response: The Safety Board recognizes that certification of single pilot operations involves "pilot testing that requires the demonstration of competent instrument operations during complex air traffic control instructions (our emphasis) to the same proficiency level as if a second-in-command were present." However, of equal or greater concern to the Board are single-pilot operations of multiengine airplanes under instrument flight rules (IFR) into airports that involve little or no air traffic control (ATC) services or instructions. This type of "operating environment" is typical of what many Part 135 operators frequently encounter. In fact, the lack of air traffic assistance when it is most needed (i.e., during poor weather, in icing conditions, at night, while executing a missed approach, etc.) can quickly escalate single-pilot workload to virtually unmanageable levels. Automation, in the form of increasingly sophisticated autopilots or flight directors, does not necessarily alleviate pilot workload in such circumstances. A Data Source: NTSB Recommendations to FAA and FAA Responses study conducted by the National Aeronautics and Space Administration (NASA) demonstrated that, while some degree of automation is beneficial in executing IFR approaches in a high workload environment, the largest numbers of errors were made by pilots using fully-automated autopilots (those featuring altitude hold and vertical/lateral navigation coupling). Overall pilot workload was increased in using the more sophisticated autopilots since they required more attention to program, interpret and monitor. In the same study, it was demonstrated also that instrument flying performance was dependent upon the type of approach being flown. Precision instrument landing system (ILS) approaches were the easiest to perform and the nondirectional beacon (NDB) approaches the most difficult. Nonprecision approaches are the type most often available at uncontrolled airports. Therefore, we believe that the level of complexity or sophistication of the "operating environment," whether in the form of ATC services or navigation aids, has an intricate and insufficiently regarded relationship to pilot workload. Analysis of single-pilot IFR (SPIFR) accident data attests to the increased workload associated with multiengine aircraft. NASA researchers analyzed Safety Board accident files for the years 1964 through 1975 inclusive. It was found that while only 45% of IFR operations were conducted in twin-engine aircraft, 58% of SPIFR accidents occurred in twin-engine aircraft. A recent examination was made of Safety Board accident data for SPIFR multiengine operations (general aviation, commuter airline, and on-demand air taxi) from 1975 through 1981. That the pilot contributes heavily to these SPIFR accidents in twin-engine aircraft is shown by the fact that in 88% (527/598) of all such accidents, the pilot is cited as a cause, a factor, or both. The Safety Board believes that the provisions of 14 CFR Part 135 do not address adequately the complex relationships between cockpit workload, aircraft equipment, and the operating environment of single-pilot multiengine IFR operations. Certification of aircraft for single-pilot operations under the general airworthiness regulations may, in fact, not sufficiently take into account many situations encountered by air-taxi operators. Seating capacity, one of the primary certifying criteria for this category, is probably the least relevant factor to the issue. Moreover, the requirement for an autopilot may in some cases only exacerbate the problem of pilot workload. Additionally, consideration should be give to peripheral duties that increase the Part 135 pilot's workload, such as making radio calls to company dispatch, filling out company paperwork, conducting passenger briefings, etc. These factors are also part of the "operating environment" to which this safety recommendation pertains. The Board believes that the "operating environment," including the route structure of each Part 135 operator, is unique and requires specific consideration of the type of aircraft equipment necessary to enhance safe operations. The need for a greater emphasis on human factors considerations in single-pilot aircraft design and operation, specifically in the areas of cockpit layout and communications/navigation equipment that organizes and reduces pilot workload, is also well documented; however, existing Federal Aviation Regulations governing the certification of aircraft of SPIFR operations do not require examination of these factors in order to match aircraft equipment with the intended operation. The Safety Board believes that the higher complexity of 14 CFR 135 operations as compared to 14 CFR 91 operations and safety considerations dictate the need for human engineering evaluations for each particular aircraft to be used in air taxi service in conjunction with the particular operation to be conducted. We trust this letter clarifies what is meant by "operating environment" and explains its relevance to the recommendation. The Safety Board asks that the FAA reconsider Data Source: NTSB Recommendations to FAA and FAA Responses its position on Safety Recommendation A-82-145. Pending your reply, and in view of your earlier stated intention to consider action completed on this recommendation, we have placed this recommendation in an "Open--Unacceptable Action" status.

From: FAA
To: NTSB
Date: 1/26/1984
Response: FAA LETTER: WE BELIEVE THE EXISTING REGULATORY REQUIREMENTS IN 14 CFR 135 ADEQUATELY ADDRESS THE OPERATING ENVIRONMENT. THE CERTIFICATE HOLDER MUST SHOW TO THE SATISFACTION OF THE ADMINISTRATOR THAT OPERATIONS CAN BE CONDUCTED SAFELY. THE REGULATIONS SPECIFICALLY ADDRESS CONDITIONS AND LIMITATIONS ON THE USE OF AUTOPILOT SYSTEMS DEEMED NECESSARY BY THE ADMINISTRATOR. PILOT TESTING REQUIRES DEMONSTRATION OF COMPETENT INSTRUMENT OPERATIONS DURING COMPLEX AIR TRAFFIC CONTROL INSTRUCTIONS TO THE SAME PROFICIENCY LEVEL AS IF A SECOND IN COMMAND WERE PRESENT.

From: NTSB
To: FAA
Date: 11/22/1983
Response: Unfortunately, the letter or recommendation transmitting Safety Recommendation A-82- 145 to the FAA contained an error in the text of the recommendation. The Board adopted the recommendation with the phrase "operating environment" in the second line. The phrase was erroneously altered during the final preparation of the letter to "operating equipment." The recommendation as adopted correctly reads as above. The text of the Safety Board's report on this accident as well as the facts and analysis included in the letter of recommendation contain the support for the recommendation that there is a need to go beyond existing pilot experience and training requirements contained in 14 CFR 135 for single-pilot multiengine IFR certification and to give consideration to the operating environment. Because the FAA response to Safety Recommendation A-82-145 was based on an evaluation of an incorrectly worded recommendation, we ask that a new response be made to the correctly worded recommendation. Pending receipt of further FAA response, A-82-145 will be held in an "Open-Acceptable Action." We regret the misdirection of your effort that the error has caused.

From: FAA
To: NTSB
Date: 1/28/1983
Response: FAA LETTER: HUMAN FACTOR ENGINEERING, AS IT RELATES TO COCKPIT DESIGN, IS AN AREA OF CONCERN TO THE FEDERAL AVIATION ADMINISTRATION, AND WE ARE AWARE OF THE IMPORTANCE THAT PROPER HUMAN ENGINEERING OF FLIGHT DECK EQUIPMENT PLAYS IN REDUCING PILOT WORKLOAD AND DESIGN INDUCED ERRORS. IN RECENT YEARS THE FAA HAS UNDERTAKEN SEVERAL PROJECTS RELATED TO SUCH AREAS.