Narrative:

While slowing at 7000 ft MSL, approaching ewr, there was audible thud that could be felt. Thinking the noise might have come from an aggressive stowage of the forward liquor cart, we queried the flight attendant who stated that had not been the case. Shortly thereafter, a flight attendant from mid-cabin came forward and reported that she had felt the occurrence in the floor and expressed her concern. With the aircraft off autoplt, we maneuvered to our satisfaction, verifying no adverse control. Engines were normal. Suspicious that there had been a cargo shift, we continued to ewr where we elected an early gear extension that was normal. On short final we had 2 more occurrences of the noise and thud. The landing was normal and with minimum braking and a roll to the end, no further noise occurred. We contacted ramp and requested that they have someone check the cargo load for movement. They verified that an ld-11 pallet had not been secured with the floor locks. 1154 pounds of cargo remained securely attached to the pallet and had moved forward approximately 20 ft to a set of stops near the cargo door. The pallet and its cargo were free to move fore and aft within this 20 ft range throughout the flight. It seems that the minimal weight, and the fortunate location of the pallet, did not adversely affect the handling of the aircraft.

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Original NASA ASRS Text

Title: FLC OF NEW TWIN ENG WDB ACFT HEARD LOUD NOISE FROM UNDERNEATH THE CABIN FLOOR DURING FINAL APCH AT DEST. IN ADDITION, A CABIN ATTENDANT IN THE ACFT'S MID-SECTION INFORMED THE CAPT THAT SHE WAS VERY CONCERNED SINCE SHE HAD FELT SOMETHING VIBRATE THE CABIN FLOOR, AND HEARD A LOUD NOISE.

Narrative: WHILE SLOWING AT 7000 FT MSL, APCHING EWR, THERE WAS AUDIBLE THUD THAT COULD BE FELT. THINKING THE NOISE MIGHT HAVE COME FROM AN AGGRESSIVE STOWAGE OF THE FORWARD LIQUOR CART, WE QUERIED THE FLT ATTENDANT WHO STATED THAT HAD NOT BEEN THE CASE. SHORTLY THEREAFTER, A FLT ATTENDANT FROM MID-CABIN CAME FORWARD AND RPTED THAT SHE HAD FELT THE OCCURRENCE IN THE FLOOR AND EXPRESSED HER CONCERN. WITH THE ACFT OFF AUTOPLT, WE MANEUVERED TO OUR SATISFACTION, VERIFYING NO ADVERSE CTL. ENGS WERE NORMAL. SUSPICIOUS THAT THERE HAD BEEN A CARGO SHIFT, WE CONTINUED TO EWR WHERE WE ELECTED AN EARLY GEAR EXTENSION THAT WAS NORMAL. ON SHORT FINAL WE HAD 2 MORE OCCURRENCES OF THE NOISE AND THUD. THE LNDG WAS NORMAL AND WITH MINIMUM BRAKING AND A ROLL TO THE END, NO FURTHER NOISE OCCURRED. WE CONTACTED RAMP AND REQUESTED THAT THEY HAVE SOMEONE CHK THE CARGO LOAD FOR MOVEMENT. THEY VERIFIED THAT AN LD-11 PALLET HAD NOT BEEN SECURED WITH THE FLOOR LOCKS. 1154 LBS OF CARGO REMAINED SECURELY ATTACHED TO THE PALLET AND HAD MOVED FORWARD APPROX 20 FT TO A SET OF STOPS NEAR THE CARGO DOOR. THE PALLET AND ITS CARGO WERE FREE TO MOVE FORE AND AFT WITHIN THIS 20 FT RANGE THROUGHOUT THE FLT. IT SEEMS THAT THE MINIMAL WT, AND THE FORTUNATE LOCATION OF THE PALLET, DID NOT ADVERSELY AFFECT THE HANDLING OF THE ACFT.

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.