An air carrier B727 flight crew reports that their recent takeoff from mex revealed that there may b...

Narrative:

Runway 23L. The takeoff performance system called for packs on. I elected for packs off. We got airborne just prior to the displaced threshold. The end of the runway and the buildings in front looked awfully close. We boosted the EPR to 2.25. Egt remained below 620 degrees C. After we were airborne and clear of the buildings, we reduced power to maximum and continued the climb about 1 min. We could not have aborted nor continued the takeoff, 2 engines, at V1. I consider the margin of error on the B727 to be too small for mex. As the WX gets hotter, I think that we should be flying mex with aircraft possessing more power and a greater performance margin. The following items should have given us even more performance. Tower called for 13 KTS headwind. Our temperature was cooler than planned. Our weight was lighter than planned. We used packs off. Planned taxi time was 18 mins. We were delayed due to traffic, and our time was 36 mins, and in spite of this we had to add power on liftoff. Callback conversation with reporter revealed the following information: the reporter said that he suspects that the winds at the mid point and the end of the runway may have been tailwinds. He has noticed that winds often differ from the broadcast winds at this airport. He does not think that the airport has a low level windshear system and he has not heard any broadcast of wind conditions other than tower winds. He has seen wind conditions that differ from the broadcast winds on numerous occasions and believes that may have been the case here. He also suspects that he had departed with a higher gross weight than that shown on the manifest. He did not request that the onboard freight be weighed this time because the crew had to xfer to another aircraft and continue their schedule, but he did inform his chief pilot of his suspicions. Allegedly, the chief pilot revealed that the company was xchking the actual weights and other performance related data at this and several other high altitude airports. The reporter still thinks that the B727-200 should not be used on this run during the summer months because its margin of performance is insufficient in high, hot conditions.

Original NASA ASRS Text

Title: AN ACR B727 FLC RPTS THAT THEIR RECENT TKOF FROM MEX REVEALED THAT THERE MAY BE A PROB WITH THE PERFORMANCE OF THE ACFT OR WITH THE PERFORMANCE DATA ITSELF.

Narrative: RWY 23L. THE TKOF PERFORMANCE SYS CALLED FOR PACKS ON. I ELECTED FOR PACKS OFF. WE GOT AIRBORNE JUST PRIOR TO THE DISPLACED THRESHOLD. THE END OF THE RWY AND THE BUILDINGS IN FRONT LOOKED AWFULLY CLOSE. WE BOOSTED THE EPR TO 2.25. EGT REMAINED BELOW 620 DEGS C. AFTER WE WERE AIRBORNE AND CLR OF THE BUILDINGS, WE REDUCED PWR TO MAX AND CONTINUED THE CLB ABOUT 1 MIN. WE COULD NOT HAVE ABORTED NOR CONTINUED THE TKOF, 2 ENGS, AT V1. I CONSIDER THE MARGIN OF ERROR ON THE B727 TO BE TOO SMALL FOR MEX. AS THE WX GETS HOTTER, I THINK THAT WE SHOULD BE FLYING MEX WITH ACFT POSSESSING MORE PWR AND A GREATER PERFORMANCE MARGIN. THE FOLLOWING ITEMS SHOULD HAVE GIVEN US EVEN MORE PERFORMANCE. TWR CALLED FOR 13 KTS HEADWIND. OUR TEMP WAS COOLER THAN PLANNED. OUR WT WAS LIGHTER THAN PLANNED. WE USED PACKS OFF. PLANNED TAXI TIME WAS 18 MINS. WE WERE DELAYED DUE TO TFC, AND OUR TIME WAS 36 MINS, AND IN SPITE OF THIS WE HAD TO ADD PWR ON LIFTOFF. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR SAID THAT HE SUSPECTS THAT THE WINDS AT THE MID POINT AND THE END OF THE RWY MAY HAVE BEEN TAILWINDS. HE HAS NOTICED THAT WINDS OFTEN DIFFER FROM THE BROADCAST WINDS AT THIS ARPT. HE DOES NOT THINK THAT THE ARPT HAS A LOW LEVEL WINDSHEAR SYS AND HE HAS NOT HEARD ANY BROADCAST OF WIND CONDITIONS OTHER THAN TWR WINDS. HE HAS SEEN WIND CONDITIONS THAT DIFFER FROM THE BROADCAST WINDS ON NUMEROUS OCCASIONS AND BELIEVES THAT MAY HAVE BEEN THE CASE HERE. HE ALSO SUSPECTS THAT HE HAD DEPARTED WITH A HIGHER GROSS WT THAN THAT SHOWN ON THE MANIFEST. HE DID NOT REQUEST THAT THE ONBOARD FREIGHT BE WEIGHED THIS TIME BECAUSE THE CREW HAD TO XFER TO ANOTHER ACFT AND CONTINUE THEIR SCHEDULE, BUT HE DID INFORM HIS CHIEF PLT OF HIS SUSPICIONS. ALLEGEDLY, THE CHIEF PLT REVEALED THAT THE COMPANY WAS XCHKING THE ACTUAL WTS AND OTHER PERFORMANCE RELATED DATA AT THIS AND SEVERAL OTHER HIGH ALT ARPTS. THE RPTR STILL THINKS THAT THE B727-200 SHOULD NOT BE USED ON THIS RUN DURING THE SUMMER MONTHS BECAUSE ITS MARGIN OF PERFORMANCE IS INSUFFICIENT IN HIGH, HOT CONDITIONS.

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.

Attributes
ACN	398299
Time
Date	199803
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mex
State Reference	FO
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B727-200
Operating Under FAR Part	Part 121
Flight Phase	climbout : takeoff
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	398299
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other
Situations
Airport	other physical facility procedure or policy : unspecified

An air carrier B727 flight crew reports that their recent takeoff from mex revealed that there may be a problem with the performance of the aircraft or with the performance data itself.