Narrative:

We departed without the re-issue of final weights after returning to gate to comply with MEL restriction. Maintenance had found several items during walk around and told us he suspected a forward lavatory flush motor problem and had to talk to maintenance control. We received ACARS message not to taxi without mrd but not to delay push so I released brakes but told the pushback crew to 'hold push while we wait for the mrd' since we had received an ACARS message saying the mrd was on the way.right after brake release we received final weights. 15 minutes later there was still no mrd; no sign of the mechanic and we were not able to contact operations at anytime while on the ground. I called maintenance control directly to inquire about the mrd and learned they were waiting for a call back from the mechanic regarding compliance with an MEL on forward lavatory flush motor. The water had to be turned off in the lavatory; and the door blocked off. The crew tried again to call operations on company frequency but still no contact.I then told the push crew that the brakes would be set; and we needed a jet bridge driver; so the mechanic could perform maintenance. I set the brakes; and then used the ACARS 'return to gate' prompt. The mechanic was then on and off the aircraft in three minutes to comply with the MEL. We then received the maintenance release; the brakes were released and the flight departed normally. Once at cruise an ACARS message was received stating 'invalid weights due to your return to blocks. Be sure you have new weights before your next departure'. The message for invalid weights was received 39 minutes after takeoff. The crew thought they had the final weights because they came out so fast after the first brake release. After using the return to gate prompt they should have sent an invalid weights message over ACARS right away.

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Original NASA ASRS Text

Title: The clumsy attempt to get an on time departure while awaiting a maintenance release resulted in an extensive ground delay and a takeoff accomplished without the appropriate weight and balance data for an A319 flight crew.

Narrative: We departed without the re-issue of Final Weights after returning to gate to comply with MEL restriction. Maintenance had found several items during walk around and told us he suspected a Forward Lavatory Flush Motor problem and had to talk to Maintenance Control. We received ACARS message not to taxi without MRD but not to delay push so I released brakes but told the pushback crew to 'hold push while we wait for the MRD' since we had received an ACARS message saying the MRD was on the way.Right after brake release we received Final Weights. 15 minutes later there was still no MRD; no sign of the mechanic and we were not able to contact Operations at anytime while on the ground. I called Maintenance Control directly to inquire about the MRD and learned they were waiting for a call back from the mechanic regarding compliance with an MEL on Forward Lavatory Flush Motor. The water had to be turned off in the lavatory; and the door blocked off. The crew tried again to call Operations on company frequency but still no contact.I then told the Push Crew that the brakes would be set; and we needed a Jet Bridge driver; so the mechanic could perform maintenance. I set the brakes; and then used the ACARS 'return to gate' prompt. The mechanic was then on and off the aircraft in three minutes to comply with the MEL. We then received the maintenance release; the brakes were released and the flight departed normally. Once at cruise an ACARS message was received stating 'INVALID WEIGHTS DUE TO YOUR RETURN TO BLOCKS. BE SURE YOU HAVE NEW WEIGHTS BEFORE YOUR NEXT DEPARTURE'. The message for Invalid Weights was received 39 minutes after takeoff. The crew thought they had the Final Weights because they came out so fast after the first brake release. After using the return to gate prompt they should have sent an Invalid Weights message over ACARS right away.

Data retrieved from NASA's ASRS site as of July 2013 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.