Narrative:

Dc-9 aircraft operating on flight to pit returned to the field after takeoff from bradley international airport, windsor locks, ct. The pilot was unable to retract the nose landing gear. Initial inspection revealed the nose landing gear strut assembly was flat having lost its air and oil at some point on takeoff. Landing gear is equipped with a spray deflector. There were visible signs of deflector striking the nose gear doors. This aircraft had a history of nose strut losing its precharge air and oil. The spray deflector can prevent ctring of the lower leg upon retraction when coming in contact with doors. Further inspection revealed the upper attach bolt on the nose landing gear retract cylinder had failed (sheared in the middle of shank). The cylinder had 10644 hours since overhaul. Having 29 yrs experience in working on dc-9 aircraft, I believe this incident of failure warrants an alert notice to all operators operating similar equipment advising of possibility of similar failure of retract cylinder attach bolts -- due to age and repeated use in normal service. Alert should call attention to paying particular attention to these bolts anytime an aircraft returns to field failing to be able to retract the landing gear following takeoff. Subsequent to next flight we svced the nose strut air and oil in accordance with the manufacturers manual and replaced the nose landing gear retract cylinder and upper attach bolt with serviceable parts from inventory. Callback conversation with reporter revealed the following information: reporter stated that there was another incident 1 week after this incident which helped bring about quick action by his company to correct this problem, such as all aircraft are either inspected each night for the condition of the strut cylinder attach bolt if the NS11-20 bolt has not been replaced by an NS62-08-25 having a 150000 pounds shear rating instead of 75000 pounds. He believes that his company has taken necessary steps to correct the problem but wonders if other operators of dc-9 aircraft have done the same! He further stated that douglas issued a recommendation for the bolt replacement after the installation of the slush/ice deflector back in 1992. However, his company did not take the present action until experiencing the present 2 incidents. According to the reporter, douglas has re-issued an action letter, and the understands that the FAA is actively involved in assuring correction of the problem. He stated that the heavier bolt is necessary to carrier the additional weight of the nose gear deflector and that a failure could cause penetration of the aircraft #110 bulkhead where all the electrical power is centralized!

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Original NASA ASRS Text

Title: FLC OF A DC-9 TYPE ACFT RETURNED TO LAND AFTER THE NOSE GEAR WOULD NOT RETRACT AFTER TKOF.

Narrative: DC-9 ACFT OPERATING ON FLT TO PIT RETURNED TO THE FIELD AFTER TKOF FROM BRADLEY INTL ARPT, WINDSOR LOCKS, CT. THE PLT WAS UNABLE TO RETRACT THE NOSE LNDG GEAR. INITIAL INSPECTION REVEALED THE NOSE LNDG GEAR STRUT ASSEMBLY WAS FLAT HAVING LOST ITS AIR AND OIL AT SOME POINT ON TKOF. LNDG GEAR IS EQUIPPED WITH A SPRAY DEFLECTOR. THERE WERE VISIBLE SIGNS OF DEFLECTOR STRIKING THE NOSE GEAR DOORS. THIS ACFT HAD A HISTORY OF NOSE STRUT LOSING ITS PRECHARGE AIR AND OIL. THE SPRAY DEFLECTOR CAN PREVENT CTRING OF THE LOWER LEG UPON RETRACTION WHEN COMING IN CONTACT WITH DOORS. FURTHER INSPECTION REVEALED THE UPPER ATTACH BOLT ON THE NOSE LNDG GEAR RETRACT CYLINDER HAD FAILED (SHEARED IN THE MIDDLE OF SHANK). THE CYLINDER HAD 10644 HRS SINCE OVERHAUL. HAVING 29 YRS EXPERIENCE IN WORKING ON DC-9 ACFT, I BELIEVE THIS INCIDENT OF FAILURE WARRANTS AN ALERT NOTICE TO ALL OPERATORS OPERATING SIMILAR EQUIP ADVISING OF POSSIBILITY OF SIMILAR FAILURE OF RETRACT CYLINDER ATTACH BOLTS -- DUE TO AGE AND REPEATED USE IN NORMAL SVC. ALERT SHOULD CALL ATTN TO PAYING PARTICULAR ATTN TO THESE BOLTS ANYTIME AN ACFT RETURNS TO FIELD FAILING TO BE ABLE TO RETRACT THE LNDG GEAR FOLLOWING TKOF. SUBSEQUENT TO NEXT FLT WE SVCED THE NOSE STRUT AIR AND OIL IN ACCORDANCE WITH THE MANUFACTURERS MANUAL AND REPLACED THE NOSE LNDG GEAR RETRACT CYLINDER AND UPPER ATTACH BOLT WITH SERVICEABLE PARTS FROM INVENTORY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THERE WAS ANOTHER INCIDENT 1 WK AFTER THIS INCIDENT WHICH HELPED BRING ABOUT QUICK ACTION BY HIS COMPANY TO CORRECT THIS PROB, SUCH AS ALL ACFT ARE EITHER INSPECTED EACH NIGHT FOR THE CONDITION OF THE STRUT CYLINDER ATTACH BOLT IF THE NS11-20 BOLT HAS NOT BEEN REPLACED BY AN NS62-08-25 HAVING A 150000 LBS SHEAR RATING INSTEAD OF 75000 LBS. HE BELIEVES THAT HIS COMPANY HAS TAKEN NECESSARY STEPS TO CORRECT THE PROB BUT WONDERS IF OTHER OPERATORS OF DC-9 ACFT HAVE DONE THE SAME! HE FURTHER STATED THAT DOUGLAS ISSUED A RECOMMENDATION FOR THE BOLT REPLACEMENT AFTER THE INSTALLATION OF THE SLUSH/ICE DEFLECTOR BACK IN 1992. HOWEVER, HIS COMPANY DID NOT TAKE THE PRESENT ACTION UNTIL EXPERIENCING THE PRESENT 2 INCIDENTS. ACCORDING TO THE RPTR, DOUGLAS HAS RE-ISSUED AN ACTION LETTER, AND THE UNDERSTANDS THAT THE FAA IS ACTIVELY INVOLVED IN ASSURING CORRECTION OF THE PROB. HE STATED THAT THE HEAVIER BOLT IS NECESSARY TO CARRIER THE ADDITIONAL WT OF THE NOSE GEAR DEFLECTOR AND THAT A FAILURE COULD CAUSE PENETRATION OF THE ACFT #110 BULKHEAD WHERE ALL THE ELECTRICAL PWR IS CENTRALIZED!

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.