B757-200 rolls backward from gate when brakes are released without tug connected.

Attributes
ACN	700244
Time
Date	200606
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	ground : pushback
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 225 flight time total : 20000 flight time type : 7500
ASRS Report	700244
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	non adherence : company policies non adherence : published procedure other anomaly
Independent Detector	other flight crewa
Resolutory Action	flight crew : regained aircraft control
Supplementary
Problem Areas	Company
Primary Problem	Company

Narrative:

Flight attendants were getting a final count; all passenger were down. Push crew called on interphone and stated checks were complete. We advised checklist complete and called for a push with ramp tower. Push crew cleared us to release brakes. I responded 'brakes released hold position.' about 5 seconds later; I noticed that we were pushing back and I called push crew to 'hold us' and then I realized that we were rolling back without the tug and the push crew's headset had unplugged when we started rolling back. I applied brakes and the aircraft jerked to a halt. We had rolled about 10-15 ft. I checked flight attendants and they were all ok and the push crew reconnected and continued our pushback.

Original NASA ASRS Text

Title: B757-200 ROLLS BACKWARD FROM GATE WHEN BRAKES ARE RELEASED WITHOUT TUG CONNECTED.

Narrative: FLT ATTENDANTS WERE GETTING A FINAL COUNT; ALL PAX WERE DOWN. PUSH CREW CALLED ON INTERPHONE AND STATED CHKS WERE COMPLETE. WE ADVISED CHKLIST COMPLETE AND CALLED FOR A PUSH WITH RAMP TWR. PUSH CREW CLRED US TO RELEASE BRAKES. I RESPONDED 'BRAKES RELEASED HOLD POS.' ABOUT 5 SECONDS LATER; I NOTICED THAT WE WERE PUSHING BACK AND I CALLED PUSH CREW TO 'HOLD US' AND THEN I REALIZED THAT WE WERE ROLLING BACK WITHOUT THE TUG AND THE PUSH CREW'S HEADSET HAD UNPLUGGED WHEN WE STARTED ROLLING BACK. I APPLIED BRAKES AND THE ACFT JERKED TO A HALT. WE HAD ROLLED ABOUT 10-15 FT. I CHKED FLT ATTENDANTS AND THEY WERE ALL OK AND THE PUSH CREW RECONNECTED AND CONTINUED OUR PUSHBACK.

Data retrieved from NASA's ASRS site as of January 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.