Narrative:

High speed abort. The B737 weighed approximately 190000 pounds for takeoff. This allowed a 'bleeds on' reduced power takeoff. Flight was cleared into position and hold runway 34R. After holding into position for approximately 2 mins, we were cleared for takeoff. The throttles were advanced and the toga button was pressed. The captain was the PF. As the throttles advanced to takeoff thrust, the #2 engine seemed to 'hunt' a bit to find the takeoff N1. This is not uncommon and it did settle down at the correct takeoff N1. After reaching the correct N1 but before throttle hold, the #2 N1 began to fluctuate a bit. Since this could be the autothrottle acting up, it did not unduly concern me. After throttle hold, the engine seemed to settle down. At the '80 KTS thrust set' callout, the engines were normal. Shortly after the '80 KT' call, the #2 engine started to fluctuate again. In short order, I made sure that throttle hold was engaged, and ruled out an autothrottle problem. I did a double take to make sure that I was really seeing what I was seeing. By this time I could hear the engine fluctuating slightly and noted that the fuel flow was fluctuating in a sync with the N1. At this point, it was obvious that the engine was not operating normally. I pulled the throttles back and the rejected takeoff engaged. I believe that the indicated airspeed reached a maximum of 110 KTS, well below the V1 speed. I quickly applied manual brakes which released the rejected takeoff braking. This worked out quite well as it made the abort less violent to the passenger. First officer noted that the speed brakes were not extended and extended them (nice work). I am sure that they would have extended automatically had I pulled the reversers. Even though I brief the abort to include use of reverse thrust, I did not use them in this case. After the fact, I tried to figure out why I had not used reverse. The best I could some up with was that I had so much runway remaining, reverse was not needed. In retrospect, this was a mistake as using reverse would have deployed the speed brakes. I have always thought of reversers as something to help slow the aircraft. Since there was no need to slow the aircraft at a greater rate than we had, I did not use them. This was the wrong way to view the reverser. I will now think of them as something that deploys the speed brakes. Hopefully, this will help in completing the abort SOP as written. As we slowed, I commanded the first officer to call the tower and report that we were aborting. I am pretty sure this first call was met by silence, as I remember the first officer calling them a second time. There was a response from tower which I believe was 'you're what?' first officer again told them that we were aborting, and that the message was received. We cleared the runway and as we slowed, I used the PA to tell the people that everything was ok and to remain seated. We slowly taxied back toward the terminal. First officer reviewed the limits chapter and determined that we were in the melt zone. We parked in the deice pad and contacted ramp to coordinate a return to gate. We also contacted maintenance control and dispatch and advised them of the event. Thanks to having done so many aborts in training, we remembered not to set the brakes. When the gate came open, we contacted maintenance again to see if it would be ok to taxi to the gate. They advised us to taxi on 1 engine and to be light on the brakes. This was accomplished and we parked at the gate and ground personnel chocked the aircraft so we did not have to engage the parking brake. From the time after the abort to the time we parked, I made a number of announcements to the passenger to calm them and explain the situation. I also used the interphone to communicate to the purser. The purser was very helpful in relaying the state of the passenger which then helped me tailor the PA announcements. At the gate, the purser told me that the engines did not sound normal during takeoff. He said he could hear the engine going up and down in its sound. If you are a company B737 pilot, you might be asking yourself 'when did I turn off the autothrottles?' I am happy to report that I did get them turned off before I parked at the gate. This, of course, is somewhat later than it should have been, which is a split second after I pulled the throttle back. This is a disappointment, as I did it just right during my pilot currency a few months back.

Google
 

Original NASA ASRS Text

Title: AFTER AN ABORT AROUND 110 KTS, THE PIC OF THE B737-500 REVIEWS HIS ERROR OF NOT USING REVERSE THRUST WHICH DELAYED THE DEPLOYMENT OF THE ACFT'S SPOILERS.

Narrative: HIGH SPD ABORT. THE B737 WEIGHED APPROX 190000 LBS FOR TKOF. THIS ALLOWED A 'BLEEDS ON' REDUCED PWR TKOF. FLT WAS CLRED INTO POS AND HOLD RWY 34R. AFTER HOLDING INTO POS FOR APPROX 2 MINS, WE WERE CLRED FOR TKOF. THE THROTTLES WERE ADVANCED AND THE TOGA BUTTON WAS PRESSED. THE CAPT WAS THE PF. AS THE THROTTLES ADVANCED TO TKOF THRUST, THE #2 ENG SEEMED TO 'HUNT' A BIT TO FIND THE TKOF N1. THIS IS NOT UNCOMMON AND IT DID SETTLE DOWN AT THE CORRECT TKOF N1. AFTER REACHING THE CORRECT N1 BUT BEFORE THROTTLE HOLD, THE #2 N1 BEGAN TO FLUCTUATE A BIT. SINCE THIS COULD BE THE AUTOTHROTTLE ACTING UP, IT DID NOT UNDULY CONCERN ME. AFTER THROTTLE HOLD, THE ENG SEEMED TO SETTLE DOWN. AT THE '80 KTS THRUST SET' CALLOUT, THE ENGS WERE NORMAL. SHORTLY AFTER THE '80 KT' CALL, THE #2 ENG STARTED TO FLUCTUATE AGAIN. IN SHORT ORDER, I MADE SURE THAT THROTTLE HOLD WAS ENGAGED, AND RULED OUT AN AUTOTHROTTLE PROB. I DID A DOUBLE TAKE TO MAKE SURE THAT I WAS REALLY SEEING WHAT I WAS SEEING. BY THIS TIME I COULD HEAR THE ENG FLUCTUATING SLIGHTLY AND NOTED THAT THE FUEL FLOW WAS FLUCTUATING IN A SYNC WITH THE N1. AT THIS POINT, IT WAS OBVIOUS THAT THE ENG WAS NOT OPERATING NORMALLY. I PULLED THE THROTTLES BACK AND THE REJECTED TKOF ENGAGED. I BELIEVE THAT THE INDICATED AIRSPD REACHED A MAX OF 110 KTS, WELL BELOW THE V1 SPD. I QUICKLY APPLIED MANUAL BRAKES WHICH RELEASED THE REJECTED TKOF BRAKING. THIS WORKED OUT QUITE WELL AS IT MADE THE ABORT LESS VIOLENT TO THE PAX. FO NOTED THAT THE SPD BRAKES WERE NOT EXTENDED AND EXTENDED THEM (NICE WORK). I AM SURE THAT THEY WOULD HAVE EXTENDED AUTOMATICALLY HAD I PULLED THE REVERSERS. EVEN THOUGH I BRIEF THE ABORT TO INCLUDE USE OF REVERSE THRUST, I DID NOT USE THEM IN THIS CASE. AFTER THE FACT, I TRIED TO FIGURE OUT WHY I HAD NOT USED REVERSE. THE BEST I COULD SOME UP WITH WAS THAT I HAD SO MUCH RWY REMAINING, REVERSE WAS NOT NEEDED. IN RETROSPECT, THIS WAS A MISTAKE AS USING REVERSE WOULD HAVE DEPLOYED THE SPD BRAKES. I HAVE ALWAYS THOUGHT OF REVERSERS AS SOMETHING TO HELP SLOW THE ACFT. SINCE THERE WAS NO NEED TO SLOW THE ACFT AT A GREATER RATE THAN WE HAD, I DID NOT USE THEM. THIS WAS THE WRONG WAY TO VIEW THE REVERSER. I WILL NOW THINK OF THEM AS SOMETHING THAT DEPLOYS THE SPD BRAKES. HOPEFULLY, THIS WILL HELP IN COMPLETING THE ABORT SOP AS WRITTEN. AS WE SLOWED, I COMMANDED THE FO TO CALL THE TWR AND RPT THAT WE WERE ABORTING. I AM PRETTY SURE THIS FIRST CALL WAS MET BY SILENCE, AS I REMEMBER THE FO CALLING THEM A SECOND TIME. THERE WAS A RESPONSE FROM TWR WHICH I BELIEVE WAS 'YOU'RE WHAT?' FO AGAIN TOLD THEM THAT WE WERE ABORTING, AND THAT THE MESSAGE WAS RECEIVED. WE CLRED THE RWY AND AS WE SLOWED, I USED THE PA TO TELL THE PEOPLE THAT EVERYTHING WAS OK AND TO REMAIN SEATED. WE SLOWLY TAXIED BACK TOWARD THE TERMINAL. FO REVIEWED THE LIMITS CHAPTER AND DETERMINED THAT WE WERE IN THE MELT ZONE. WE PARKED IN THE DEICE PAD AND CONTACTED RAMP TO COORDINATE A RETURN TO GATE. WE ALSO CONTACTED MAINT CTL AND DISPATCH AND ADVISED THEM OF THE EVENT. THANKS TO HAVING DONE SO MANY ABORTS IN TRAINING, WE REMEMBERED NOT TO SET THE BRAKES. WHEN THE GATE CAME OPEN, WE CONTACTED MAINT AGAIN TO SEE IF IT WOULD BE OK TO TAXI TO THE GATE. THEY ADVISED US TO TAXI ON 1 ENG AND TO BE LIGHT ON THE BRAKES. THIS WAS ACCOMPLISHED AND WE PARKED AT THE GATE AND GND PERSONNEL CHOCKED THE ACFT SO WE DID NOT HAVE TO ENGAGE THE PARKING BRAKE. FROM THE TIME AFTER THE ABORT TO THE TIME WE PARKED, I MADE A NUMBER OF ANNOUNCEMENTS TO THE PAX TO CALM THEM AND EXPLAIN THE SIT. I ALSO USED THE INTERPHONE TO COMMUNICATE TO THE PURSER. THE PURSER WAS VERY HELPFUL IN RELAYING THE STATE OF THE PAX WHICH THEN HELPED ME TAILOR THE PA ANNOUNCEMENTS. AT THE GATE, THE PURSER TOLD ME THAT THE ENGS DID NOT SOUND NORMAL DURING TKOF. HE SAID HE COULD HEAR THE ENG GOING UP AND DOWN IN ITS SOUND. IF YOU ARE A COMPANY B737 PLT, YOU MIGHT BE ASKING YOURSELF 'WHEN DID I TURN OFF THE AUTOTHROTTLES?' I AM HAPPY TO RPT THAT I DID GET THEM TURNED OFF BEFORE I PARKED AT THE GATE. THIS, OF COURSE, IS SOMEWHAT LATER THAN IT SHOULD HAVE BEEN, WHICH IS A SPLIT SECOND AFTER I PULLED THE THROTTLE BACK. THIS IS A DISAPPOINTMENT, AS I DID IT JUST RIGHT DURING MY PLT CURRENCY A FEW MONTHS BACK.

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.