Narrative:

All preflight; engine start; taxi out checks completed normally. Final weights had the trim set at 38.3. Once takeoff power was added; I immediately noticed a strong nose-up tendency; one which I have not felt since my tenure on the airbus. I made a comment to the captain that something felt odd. With the control stick full down in order to maintain directional control via the nosewheel; I elected to accelerate a bit to see if relative flow over the horizontal stabilizer would help alleviate this tail heavy scenario. After about 70 KTS; I was hesitant to neutralize the stick as it gave the feel the nosewheel was going to lift off the ground. An abort was executed around 70 KTS. We cleared the runway and returned to the gate without further incident. I discussed with the captain on how the aircraft felt and my concerns of possible improper loading of the aircraft. I knew the center of gravity was aft as the trim setting was 38.3 (unusual aft setting); although within limits on paper; in all my 10 yrs experience on airbus; had never felt the way this takeoff felt. After parked at the gate and exiting the cockpit; we began noticing visual cues. With a load of 3-83; the majority of passenger were in the last 15 rows. Once on the ramp; we quickly observed the nosewheel strut in an unusual extended position. We then met with ramp personnel and reviewed the load manifest. We were told by lead agent that the aft limit for this flight toady was 1672 units and the aircraft was actually loaded to 1680 units. When queried about the out of range number; we were told that 'there is slop built into the limits.' we moved 14 bags to the forward pit and some passenger to first class. After waiting for our brakes to cool and a visual inspection by a mechanic; we departed about 60 mins later. Trim was now at 35.9 and takeoff felt normal. A few questions come to mind: why is the aircraft being loaded in the manner it did? Plenty of room in forward pit but most bags placed in aft pit (zone 6). Was there an error in the weighing of bags; or were there some unusually heavy bags? Passenger seated primarily in the aft cabin -- why? Cheap seats? Maybe a cheap class of seat needs to spread evenly in cabin. Why is there slop/tolerance in an aft center of gravity limit? Is not a limit a limit? If anything; the slop should be set on the more conservative side of the limit! To me; the nosewheel told the whole story. Viewing the aircraft with the nose strut in an extend position was a major sign that even though on paper we were within limits; in reality the aft center of gravity may have been compromised. Supplemental information from acn 796178: first officer was the PF. On takeoff; shortly after power up; the aircraft became very light on the nosewheel. The first officer stated 'something is not right.' he told me later he had the stick full forward. At the same time he instinctively rolled in approximately a half turn of forward trim. Again he said 'the plane does not feel right.' at the same time we got the takeoff confign warning and aborted the takeoff. The abort was between 70-80 KTS. After clearing the runway; the first officer had time to explain to me what he felt; which was the airplane was too tail heavy. Since we had to wait on the brakes to cool and there was a gate available; I decided to go back to the gate. The load planner met us with the paperwork. The limit in the tail was 1672 and the aircraft had 1680 loaded in the tail. I was told there is 'slop in the limit.' upon exiting the aircraft; I noticed the nose strut was fully extended (aircraft still loaded with passenger on board). The load was 3 in first and 107 in rear; most of which were aft of the window exit; as forward of that is better seating. The mac given was 38.3%. After moving some bags up front and upgrading a tow to first class; the nose strut compressed and looked normal. The ensuing takeoff was normal. It is my belief that this airplane; though within limits on paper; had a center of gravity abnormally aft. On this particular flight; most of passenger were in rear. Also; because there was no ECAM until after the first officer rolled the trim wheel forward; there was momentary delay in communicating theneed for the abort. Other stats: takeoff gross weight 141.3; zero fuel weight 122.0.

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Original NASA ASRS Text

Title: A320 FLT CREW REPORTS TAIL HEAVY SENSATION DURING TKOF ROLL AND REJECTS.

Narrative: ALL PREFLT; ENG START; TAXI OUT CHKS COMPLETED NORMALLY. FINAL WTS HAD THE TRIM SET AT 38.3. ONCE TKOF PWR WAS ADDED; I IMMEDIATELY NOTICED A STRONG NOSE-UP TENDENCY; ONE WHICH I HAVE NOT FELT SINCE MY TENURE ON THE AIRBUS. I MADE A COMMENT TO THE CAPT THAT SOMETHING FELT ODD. WITH THE CTL STICK FULL DOWN IN ORDER TO MAINTAIN DIRECTIONAL CTL VIA THE NOSEWHEEL; I ELECTED TO ACCELERATE A BIT TO SEE IF RELATIVE FLOW OVER THE HORIZ STABILIZER WOULD HELP ALLEVIATE THIS TAIL HVY SCENARIO. AFTER ABOUT 70 KTS; I WAS HESITANT TO NEUTRALIZE THE STICK AS IT GAVE THE FEEL THE NOSEWHEEL WAS GOING TO LIFT OFF THE GND. AN ABORT WAS EXECUTED AROUND 70 KTS. WE CLRED THE RWY AND RETURNED TO THE GATE WITHOUT FURTHER INCIDENT. I DISCUSSED WITH THE CAPT ON HOW THE ACFT FELT AND MY CONCERNS OF POSSIBLE IMPROPER LOADING OF THE ACFT. I KNEW THE CTR OF GRAVITY WAS AFT AS THE TRIM SETTING WAS 38.3 (UNUSUAL AFT SETTING); ALTHOUGH WITHIN LIMITS ON PAPER; IN ALL MY 10 YRS EXPERIENCE ON AIRBUS; HAD NEVER FELT THE WAY THIS TKOF FELT. AFTER PARKED AT THE GATE AND EXITING THE COCKPIT; WE BEGAN NOTICING VISUAL CUES. WITH A LOAD OF 3-83; THE MAJORITY OF PAX WERE IN THE LAST 15 ROWS. ONCE ON THE RAMP; WE QUICKLY OBSERVED THE NOSEWHEEL STRUT IN AN UNUSUAL EXTENDED POS. WE THEN MET WITH RAMP PERSONNEL AND REVIEWED THE LOAD MANIFEST. WE WERE TOLD BY LEAD AGENT THAT THE AFT LIMIT FOR THIS FLT TOADY WAS 1672 UNITS AND THE ACFT WAS ACTUALLY LOADED TO 1680 UNITS. WHEN QUERIED ABOUT THE OUT OF RANGE NUMBER; WE WERE TOLD THAT 'THERE IS SLOP BUILT INTO THE LIMITS.' WE MOVED 14 BAGS TO THE FORWARD PIT AND SOME PAX TO FIRST CLASS. AFTER WAITING FOR OUR BRAKES TO COOL AND A VISUAL INSPECTION BY A MECH; WE DEPARTED ABOUT 60 MINS LATER. TRIM WAS NOW AT 35.9 AND TKOF FELT NORMAL. A FEW QUESTIONS COME TO MIND: WHY IS THE ACFT BEING LOADED IN THE MANNER IT DID? PLENTY OF ROOM IN FORWARD PIT BUT MOST BAGS PLACED IN AFT PIT (ZONE 6). WAS THERE AN ERROR IN THE WEIGHING OF BAGS; OR WERE THERE SOME UNUSUALLY HVY BAGS? PAX SEATED PRIMARILY IN THE AFT CABIN -- WHY? CHEAP SEATS? MAYBE A CHEAP CLASS OF SEAT NEEDS TO SPREAD EVENLY IN CABIN. WHY IS THERE SLOP/TOLERANCE IN AN AFT CTR OF GRAVITY LIMIT? IS NOT A LIMIT A LIMIT? IF ANYTHING; THE SLOP SHOULD BE SET ON THE MORE CONSERVATIVE SIDE OF THE LIMIT! TO ME; THE NOSEWHEEL TOLD THE WHOLE STORY. VIEWING THE ACFT WITH THE NOSE STRUT IN AN EXTEND POS WAS A MAJOR SIGN THAT EVEN THOUGH ON PAPER WE WERE WITHIN LIMITS; IN REALITY THE AFT CTR OF GRAVITY MAY HAVE BEEN COMPROMISED. SUPPLEMENTAL INFO FROM ACN 796178: FO WAS THE PF. ON TKOF; SHORTLY AFTER PWR UP; THE ACFT BECAME VERY LIGHT ON THE NOSEWHEEL. THE FO STATED 'SOMETHING IS NOT RIGHT.' HE TOLD ME LATER HE HAD THE STICK FULL FORWARD. AT THE SAME TIME HE INSTINCTIVELY ROLLED IN APPROX A HALF TURN OF FORWARD TRIM. AGAIN HE SAID 'THE PLANE DOES NOT FEEL RIGHT.' AT THE SAME TIME WE GOT THE TKOF CONFIGN WARNING AND ABORTED THE TKOF. THE ABORT WAS BTWN 70-80 KTS. AFTER CLRING THE RWY; THE FO HAD TIME TO EXPLAIN TO ME WHAT HE FELT; WHICH WAS THE AIRPLANE WAS TOO TAIL HVY. SINCE WE HAD TO WAIT ON THE BRAKES TO COOL AND THERE WAS A GATE AVAILABLE; I DECIDED TO GO BACK TO THE GATE. THE LOAD PLANNER MET US WITH THE PAPERWORK. THE LIMIT IN THE TAIL WAS 1672 AND THE ACFT HAD 1680 LOADED IN THE TAIL. I WAS TOLD THERE IS 'SLOP IN THE LIMIT.' UPON EXITING THE ACFT; I NOTICED THE NOSE STRUT WAS FULLY EXTENDED (ACFT STILL LOADED WITH PAX ON BOARD). THE LOAD WAS 3 IN FIRST AND 107 IN REAR; MOST OF WHICH WERE AFT OF THE WINDOW EXIT; AS FORWARD OF THAT IS BETTER SEATING. THE MAC GIVEN WAS 38.3%. AFTER MOVING SOME BAGS UP FRONT AND UPGRADING A TOW TO FIRST CLASS; THE NOSE STRUT COMPRESSED AND LOOKED NORMAL. THE ENSUING TKOF WAS NORMAL. IT IS MY BELIEF THAT THIS AIRPLANE; THOUGH WITHIN LIMITS ON PAPER; HAD A CTR OF GRAVITY ABNORMALLY AFT. ON THIS PARTICULAR FLT; MOST OF PAX WERE IN REAR. ALSO; BECAUSE THERE WAS NO ECAM UNTIL AFTER THE FO ROLLED THE TRIM WHEEL FORWARD; THERE WAS MOMENTARY DELAY IN COMMUNICATING THENEED FOR THE ABORT. OTHER STATS: TKOF GROSS WT 141.3; ZERO FUEL WT 122.0.

Data retrieved from NASA's ASRS site as of May 2009 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.