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Safety Recommendation Details

Safety Recommendation A-81-107
Details
Synopsis: ON JUNE 19, 1980, A MCDONNELL DOUGLAS DC-9-80, N1002G, SKIDDED OFF THE RIGHT SIDE OF RUNWAY 21R WHILE ATTEMPTING A SIMULATED HYDRAULIC SYSTEMS INOPERATIVE LANDING AT THE YUMA INTERNATIONAL AIRPORT, YUMA, ARIZONA. THE AIRCRAFT CAME TO REST ABOUT 6,700 FEET BEYOND THE LANDING THRESHOLD OF THE RUNWAY. THE AIRCRAFT WAS DAMAGED SUBSTANTIALLY; HOWEVER, THE THREE FLIGHTCREW MEMBERS WERE NOT INJURED. THERE WERE NO PASSENGERS. THE PURPOSE OF THE FLIGHT WAS TO DEMONSTRATE THAT THE AIRCRAFT COULD BE FLOWN AND LANDED SAFELY WITH A COMPLETE FAILURE OF ITS HYDRAULIC SYSTEMS TO DEMONSTRATE COMPLIANCE WITH A SPECIAL CONDITION TO THE PROVISIONS OF 14 CFR 25. (FOR MORE INFORMATION READ NTSB-AAR-81-16.)
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: INCORPORATE THE FOLLOWING INFORMATION IN THE DC-9 SERIES -10 THROGH -50 AIRCRAFT FLIGHT MANUALS UNDER THE ABNORMAL HYDRAULICS-OUT LANDING SECTION AND THE NORMAL LANDINGS ON WET/SLIPPERY RUNWAYS SECTION: THE MAXIMUM RUDDER EFFECTIVENESS AVAILABLE IS SUBSTANTIALLY REDUCED DURING REVERSE THRUST OPERATION AS FOLLOWS: ENGINE THRUST MAXIMUM RUDDER SETTING EFFECTIVENESS AVAILABLE(PERCENT)*/ FORWARD IDLE 100 REVERSE IDLE 65 1.3 EPR (REVERSE) 25 1.6 EPR (REVERSE) MINIMAL */RUDDER EFFECTIVENESS ALSO DECREASES WITH DECREASING AIRSPEED.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: Yuma, AZ, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: LAX80FA111
Accident Reports: McDonnell Douglas Corporation, DC-9-80, N1002G
Report #: AAR-81-16
Accident Date: 6/19/1980
Issue Date: 9/15/1981
Date Closed: 3/19/1985
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 3/19/1985
Response: We note that the Airplane Flight Manuals (AFM) for all models of the DC-9 series now have been revised to provide detailed discussions of the adverse effect of reverse thrust on rudder effectiveness and directional control and to stipulate procedures for the use of reverse thrust for landing on wet/slippery runways and when landing with complete loss of hydraulic systems' pressure. These revisions to the DC-9 AFM are in consonance with Safety Recommendation A-81-107 which is classified "Closed--Acceptable Action."

From: FAA
To: NTSB
Date: 11/2/1984
Response: FAA LTR: THE FAA APPROVED AIRPLANE FLIGHT MANUALS (AFM) FOR ALL MODELS OF THE DC-9 SERIES HAVE NOW BEEN REVISED TO PROVIDE DETAILED DISCUSSIONS OF THE ADVERSE EFFECT OF REVERSE THRUST ON RUDDER EFFECTIVENESS AND DIRECTIONAL CONTROL AND TO PROVIDE PROCEDURES FOR USE OF REVERSE THRUST FOR LANDINGS ON WET/SLIPPERY RUNWAYS AND WHEN LANDING WITH COMPLETE LOSS OF HYDRAULIC SYSTEM PRESSURE.

From: NTSB
To: FAA
Date: 5/29/1984
Response: Copies of the appropriate pages of the FAA-approved Aircraft Flight Manual (AFM) for the McDonnell Douglas DC-9-50 and -80 airplanes enclosed with your letter partially satisfy the intent of the Board's Safety Recommendations for informing pilots of the reduction in rudder control due to application of reverse thrust. We must note that there was no indication in your letter as to whether DC-9's other than the models - 50 and -80 had this information included in their respective AFM's. It was also noted that a stopping distance for a nominal weight, sea level, dry runway condition had been added to the DC-9-80 and -50 AFM's for the landing condition with no hydraulic power. While this is useful information and was added to partially satisfy Safety Recommendation A-81-112, it could be misleading to flightcrews. Normally, landing distances which incorporate safety margins are given rather than pure stopping distances. It is suggested that appropriate landing distances as originally recommended in A-81-112 be supplied in lieu of the stopping distances. Safety Recommendation A-81-107 will be classified as "Open--Unacceptable Action" pending our review of the updated AFM's and further response from the FAA regarding DC-9 models other than the -50 and -80. Safety Recommendation A-81-104 has been classified as "Closed--Acceptable Alternate Action."

From: FAA
To: NTSB
Date: 1/26/1984
Response: FAA LETTER: ENCLOSED FOR THE BOARD'S INFORMATION AND FILE ARE COPIES OF THE APPROPRIATE PAGES OF THE FEDERAL AVIATION ADMINISTRATION'S (FAA) APPROVED AIRPLANE FLIGHT MANUAL (AFM) FOR THE MCDONNELL DOUGLAS DC-9-50 AND -80 AIRPLANES. THIS AMENDMENT TO THE AFM ESTABLISHES PROCEDURES FOR HANDLING ABNORMAL HYDRAULICS-OUT LANDINGS.

From: NTSB
To: FAA
Date: 5/12/1983
Response: The Safety Board still believes the quantitative chart information concerning rudder effectiveness as a function of forward and reverse thrust should be issued to provide the pilot with information regarding factors affecting directional control on the ground during thrust reverser operation. However, we agree that the proposed changes to the FAA-approved Airplane Flight Manual should, when implemented, provide significant information to the pilots. Therefore, these recommendations will remain in an "Open--Acceptable Alternate Action" status pending completion of the Airplane Flight Manual changes.

From: FAA
To: NTSB
Date: 7/12/1982
Response: FAA LETTER: THE FAA CONCURS WITH THE BASIC INTENT OF THESE RECOMMENDATIONS OF PROVIDING THE PILOT WITH MEANINGFUL INFORMATION REGARDING THE FACTORS AFFECTING DIRECTIONAL CONTROL ON THE GROUND DURING REVERSE THRUST OPERATION. HOWEVER, WE DISAGREE WITH PROVIDING QUANTITATIVE CHART INFORMATION WITH RESPECT TO RUDDER EFFECTIVENESS AS A FUNCTION OF FORWARD AND REVERSE THRUST. THE DIRECTIONAL CONTROL CAPABILITY OF THE DC-9-80 VARIES WITH THE EFFECTIVE NESS OF THE RUDDER, NOSE WHEEL STEERING, AND DIFFERENTIAL BRAKING. WE BELIEVE THAT PROVIDING A CHART THAT SINGLES OUT ONLY ONE OF THE ABOVE ELEMENTS OF DIRECTIONAL CONTROL TENDS TO BE CONFUSING RATHER THAN CLARIFYING. INSTEAD, WE RECOMMEND THAT THE LANDING WITH NO HYDRAULIC POWER SECTION AND THE REVERSE THRUST GROUND OPERATION SECTION IN THE FAA APPROVED AIRPLANE FLIGHT MANUAL (AFM) BE MODIFIED TO DISCUSS THE FACTORS AFFECTING DIRECTIONAL CONTROL DURING REVERSE THRUST OPERATION. WE CONCUR WITH THE NTSB RECOMMENDATION TO EMPHASIZE THE NEED TO CAREFULLY MONITOR AND MAINTAIN SYMMETRIC REVERSE THRUST TO AVOID ADVERSE YAWING MOMENTS AND HAVE EMPHASIZED THIS IN THE REVISED PROCEDURES (SEE ENCLOSURE, APPENDIX A THROUGH D). THESE PROCEDURES HAVE BEEN COORDINATED WITH DOUGLAS AND FAA PERSONNEL AND WILL BE INCORPORATED IN THE DC-9-80 AFM'S.

From: NTSB
To: FAA
Date: 7/8/1982
Response: Your reply indicated that an in-depth evaluation of these recommendations would be conducted at meetings between FAA and aircraft manufacturer representatives; therefore, these recommendations have been classified as "Open--Acceptable Action," pending receipt of your findings.

From: FAA
To: NTSB
Date: 12/30/1981
Response: FAA LTR: THE FAA CONCURS IN THE INTENT OF THIS RECOMMENDATION AND AGREES THAT FURTHER STUDY AS RECOMMENDED IN A-81-104, 107, 110, AND 112 IS DESIRABLE. HOWEVER, A MEANINGFUL RESPONSE TO THESE RECOMMENDATIONS AT THIS TIME WOULD BE PREMATURE. MEETINGS ARE SCHEDULED IN THE NEAR FUTURE BETWEEN FAA AND MCDONNELL DOUGLAS REPRESENTATIVES TO CONDUCT AN IN-DEPTH EVALUATION OF EACH RECOMMENDATION. ESTIMATED COMPLETION DATE OF THESE DISCUSSIONS IS EARLY JANUARY 1982. AT THE CONCLUSION OF THESE EVALUATIONS, THE BOARD WILL BE INFORMED OF OUR FINDINGS.