Narrative:

We were at the gate in midway following the first leg of the day. The captain and I had been heatedly discussing some techniques that we didn't see eye-to-eye on. We were in a heavy (118200 pounds) B737-300 without an APU, so we had to gate start with a cart, fly an unpressurized bleeds-off takeoff (my first ever) from a wet-good runway with a tailwind. I had run the numbers in the opc and it required a flaps 15 degrees, best case gave only 21 ft of stopping distance off of runway 31C. We briefed the flaps 15 degree takeoff, but with my mind on other things, when the captain called for flaps 5 degrees (habit patterns) after engine start, I didn't catch it and tracked the flaps to 5 degrees. Neither of us caught the mistake. On takeoff roll approaching the 2000 ft remaining mark, I saw the captain pulling back on the yoke. We had set trim at 3.5 units and it was a long pull. That was when it hit me that we hadn't set the flaps to 15 degrees as required by the opc. We cleared the fence at the departure end and the rest of the climb out was uneventful. When we ran the numbers on the way to our next city, we found we were over 4000 pounds too heavy for a flaps 5 degree takeoff. There were too many distrs poorly handled on my part to effectively back up the captain on setting the proper takeoff flap setting. I was still upset by our ' discussion' and unhappy about the lack of resolution of the conflict. I was also preoccupied by the limited amount of stopping distance and the unfamiliar, unpressurized takeoff procedures than I should have been. I also believe this was my first flaps 15 degree takeoff since starting here at the company, so there were plenty of distrs to go around. We were rushing because of the gate start required by the inoperative APU, and everything snowballed. Supplemental information from acn 626017: due to distrs, we failed to put the flaps in the proper position. The aircraft accelerated, rotated and flew quite normally.

Related reports:

Google
 

Original NASA ASRS Text

Title: A LONG PULL WAS REQUIRED ON THE CTL COLUMN BY THE PIC OF A B737-300 ON A FLAP 5 DEG TKOF WHICH REQUIRED A 15 DEG FLAP SETTING FOR THE TKOF PROC AT MDW.

Narrative: WE WERE AT THE GATE IN MIDWAY FOLLOWING THE FIRST LEG OF THE DAY. THE CAPT AND I HAD BEEN HEATEDLY DISCUSSING SOME TECHNIQUES THAT WE DIDN'T SEE EYE-TO-EYE ON. WE WERE IN A HVY (118200 LBS) B737-300 WITHOUT AN APU, SO WE HAD TO GATE START WITH A CART, FLY AN UNPRESSURIZED BLEEDS-OFF TKOF (MY FIRST EVER) FROM A WET-GOOD RWY WITH A TAILWIND. I HAD RUN THE NUMBERS IN THE OPC AND IT REQUIRED A FLAPS 15 DEGS, BEST CASE GAVE ONLY 21 FT OF STOPPING DISTANCE OFF OF RWY 31C. WE BRIEFED THE FLAPS 15 DEG TKOF, BUT WITH MY MIND ON OTHER THINGS, WHEN THE CAPT CALLED FOR FLAPS 5 DEGS (HABIT PATTERNS) AFTER ENG START, I DIDN'T CATCH IT AND TRACKED THE FLAPS TO 5 DEGS. NEITHER OF US CAUGHT THE MISTAKE. ON TKOF ROLL APCHING THE 2000 FT REMAINING MARK, I SAW THE CAPT PULLING BACK ON THE YOKE. WE HAD SET TRIM AT 3.5 UNITS AND IT WAS A LONG PULL. THAT WAS WHEN IT HIT ME THAT WE HADN'T SET THE FLAPS TO 15 DEGS AS REQUIRED BY THE OPC. WE CLRED THE FENCE AT THE DEP END AND THE REST OF THE CLBOUT WAS UNEVENTFUL. WHEN WE RAN THE NUMBERS ON THE WAY TO OUR NEXT CITY, WE FOUND WE WERE OVER 4000 LBS TOO HVY FOR A FLAPS 5 DEG TKOF. THERE WERE TOO MANY DISTRS POORLY HANDLED ON MY PART TO EFFECTIVELY BACK UP THE CAPT ON SETTING THE PROPER TKOF FLAP SETTING. I WAS STILL UPSET BY OUR ' DISCUSSION' AND UNHAPPY ABOUT THE LACK OF RESOLUTION OF THE CONFLICT. I WAS ALSO PREOCCUPIED BY THE LIMITED AMOUNT OF STOPPING DISTANCE AND THE UNFAMILIAR, UNPRESSURIZED TKOF PROCS THAN I SHOULD HAVE BEEN. I ALSO BELIEVE THIS WAS MY FIRST FLAPS 15 DEG TKOF SINCE STARTING HERE AT THE COMPANY, SO THERE WERE PLENTY OF DISTRS TO GO AROUND. WE WERE RUSHING BECAUSE OF THE GATE START REQUIRED BY THE INOP APU, AND EVERYTHING SNOWBALLED. SUPPLEMENTAL INFO FROM ACN 626017: DUE TO DISTRS, WE FAILED TO PUT THE FLAPS IN THE PROPER POSITION. THE ACFT ACCELERATED, ROTATED AND FLEW QUITE NORMALLY.

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.