Air carrier large transport lost number 7 main mount on landing.

Attributes
ACN	100896
Time
Date	198812
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : ewr
State Reference	NJ
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	Mixed
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	landing other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 150 flight time total : 18000 flight time type : 1000
ASRS Report	100896
Person 2
Affiliation	company : air carrier
Function	other personnel other
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other other : unspecified
Resolutory Action	none taken : detected after the fact
Consequence	faa : investigated
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

On landing ewr 22L lost #7 tire and wheel. T/D, rollout, braking all normal with no abnormal indications at all. Parked at gate ewr and was informed by crew chief that #7 tire and wheel were missing. Informed ewr ground control on 121.8 to check runway 22L for debris. End of incident. Evidently #7 brake was locked and antiskid was not working. Entire wheel assembly was missing. I assume it sheared off on T/D which could have resulted in a fire or failure of other tires on that gear. Why the antiskid failed or the tire and wheel came off, I don't know. It could have been serious. Callback conversation with reporter revealed the following: this is second incident of this type on this air carrier and there are about 7 or 8 occurrences in the industry with this model aircraft. Wheel and brake assembly were found next morning intact on airport with no skid damaged on tire, so must have twisted off immediately on T/D. On climb out of previous station did get anti skid failure light, but it went out on descent, so may have been caused by heat from seized bearing and then went out when later cooled. Apparently problem always occurs on #7 wheel. No one on flight felt anything and did not realize wheel gone until pointed out after gate arrival.

Original NASA ASRS Text

Title: ACR LGT LOST NUMBER 7 MAIN MOUNT ON LNDG.

Narrative: ON LNDG EWR 22L LOST #7 TIRE AND WHEEL. T/D, ROLLOUT, BRAKING ALL NORMAL WITH NO ABNORMAL INDICATIONS AT ALL. PARKED AT GATE EWR AND WAS INFORMED BY CREW CHIEF THAT #7 TIRE AND WHEEL WERE MISSING. INFORMED EWR GND CTL ON 121.8 TO CHK RWY 22L FOR DEBRIS. END OF INCIDENT. EVIDENTLY #7 BRAKE WAS LOCKED AND ANTISKID WAS NOT WORKING. ENTIRE WHEEL ASSEMBLY WAS MISSING. I ASSUME IT SHEARED OFF ON T/D WHICH COULD HAVE RESULTED IN A FIRE OR FAILURE OF OTHER TIRES ON THAT GEAR. WHY THE ANTISKID FAILED OR THE TIRE AND WHEEL CAME OFF, I DON'T KNOW. IT COULD HAVE BEEN SERIOUS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: THIS IS SECOND INCIDENT OF THIS TYPE ON THIS ACR AND THERE ARE ABOUT 7 OR 8 OCCURRENCES IN THE INDUSTRY WITH THIS MODEL ACFT. WHEEL AND BRAKE ASSEMBLY WERE FOUND NEXT MORNING INTACT ON ARPT WITH NO SKID DAMAGED ON TIRE, SO MUST HAVE TWISTED OFF IMMEDIATELY ON T/D. ON CLBOUT OF PREVIOUS STATION DID GET ANTI SKID FAILURE LIGHT, BUT IT WENT OUT ON DSCNT, SO MAY HAVE BEEN CAUSED BY HEAT FROM SEIZED BEARING AND THEN WENT OUT WHEN LATER COOLED. APPARENTLY PROB ALWAYS OCCURS ON #7 WHEEL. NO ONE ON FLT FELT ANYTHING AND DID NOT REALIZE WHEEL GONE UNTIL POINTED OUT AFTER GATE ARR.

Data retrieved from NASA's ASRS site as of August 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.