Narrative:

We were going into sfo and had crossing restrictions to comply with. However, we were held up at 33000' and going high on our profile. Finally, we were cleared down to FL290 and started a 2000 FPM rate of descent. Going through approximately 31100' we were given instructions to stop our descent at FL310 for pop-up military traffic crossing below us. The first officer was flying and promptly dialed in a rate of climb on the DFGS, but with our high rate of descent we sunk down to approximately 30650' before climbing back to FL310. We had the seat belt sign off at the time, so were reluctant to disconnect the autoplt and pull back hard on the yoke to effect a more violent level-off, fearing we would hurt the F/a's and passenger that may have been walking around in the cabin. I feel that the controller's late instruction and lack of urgency in his voice was a major factor in this excursion. Also, with the high descent rate (2000 FPM) going, it is not possible to overcome the inertia of a 120000 pounds aircraft instantly. We had the military fgt in sight below us the whole time of the incident and at no time was there any threat of a near miss or collision. We had the safety of the passenger and F/a's to consider in our level-off, as well as the threat of conflicting traffic below us.

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Original NASA ASRS Text

Title: FGT POPPED UP OUT OF WARNING AREA. CTLR STOPS DESCENT ON MLG TO PROVIDE SEPARATION.

Narrative: WE WERE GOING INTO SFO AND HAD XING RESTRICTIONS TO COMPLY WITH. HOWEVER, WE WERE HELD UP AT 33000' AND GOING HIGH ON OUR PROFILE. FINALLY, WE WERE CLRED DOWN TO FL290 AND STARTED A 2000 FPM RATE OF DSNT. GOING THROUGH APPROX 31100' WE WERE GIVEN INSTRUCTIONS TO STOP OUR DSNT AT FL310 FOR POP-UP MIL TFC XING BELOW US. THE F/O WAS FLYING AND PROMPTLY DIALED IN A RATE OF CLB ON THE DFGS, BUT WITH OUR HIGH RATE OF DSNT WE SUNK DOWN TO APPROX 30650' BEFORE CLBING BACK TO FL310. WE HAD THE SEAT BELT SIGN OFF AT THE TIME, SO WERE RELUCTANT TO DISCONNECT THE AUTOPLT AND PULL BACK HARD ON THE YOKE TO EFFECT A MORE VIOLENT LEVEL-OFF, FEARING WE WOULD HURT THE F/A'S AND PAX THAT MAY HAVE BEEN WALKING AROUND IN THE CABIN. I FEEL THAT THE CTLR'S LATE INSTRUCTION AND LACK OF URGENCY IN HIS VOICE WAS A MAJOR FACTOR IN THIS EXCURSION. ALSO, WITH THE HIGH DSNT RATE (2000 FPM) GOING, IT IS NOT POSSIBLE TO OVERCOME THE INERTIA OF A 120000 LBS ACFT INSTANTLY. WE HAD THE MIL FGT IN SIGHT BELOW US THE WHOLE TIME OF THE INCIDENT AND AT NO TIME WAS THERE ANY THREAT OF A NEAR MISS OR COLLISION. WE HAD THE SAFETY OF THE PAX AND F/A'S TO CONSIDER IN OUR LEVEL-OFF, AS WELL AS THE THREAT OF CONFLICTING TFC BELOW US.

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.