A mechanic and inspector assert crj-700 maintenance procedures are not satisfactory for verifying fl...

Narrative:

We performed left wing flap actuator replacement; four total. I was the inspector along with mechanic Y; who signed-off the maintenance performed and I signed the rii [inspection]. I double-checked all maintenance that was performed on the left-hand flaps that night. I followed the procedures on how to check and make sure there was no lateral movement of the flap torque tubes; which at the time there was none detected. [Two months later]; at ZZZ1; while the plane was in-flight; the flight crew received a flap warning. Upon landing it was discovered that the #1 left-hand flap torque tube was disconnected with the bolt still in the torque tube.we need to have a go/no-go gauge fashioned so next time we can detect a problem before the aircraft leaves the maintenance base. Just tugging on the torque tubes is not satisfactory..there needs to be a backup plan; this kind of incident has happened too much.

Original NASA ASRS Text

Title: A Mechanic and Inspector assert CRJ-700 Maintenance Procedures are not satisfactory for verifying flap torque tube locking bolts are properly engaged with flap actuator drive spline shafts. A CRJ-700 flight crew had received a flap warning in flight. Flap torque tube found disconnected.

Narrative: We performed left wing flap actuator replacement; four total. I was the Inspector along with Mechanic Y; who signed-off the maintenance performed and I signed the RII [Inspection]. I double-checked all maintenance that was performed on the left-hand flaps that night. I followed the procedures on how to check and make sure there was no lateral movement of the flap torque tubes; which at the time there was none detected. [Two months later]; at ZZZ1; while the plane was in-flight; the flight crew received a flap warning. Upon landing it was discovered that the #1 left-hand flap torque tube was disconnected with the bolt still in the torque tube.We need to have a Go/No-Go gauge fashioned so next time we can detect a problem before the aircraft leaves the Maintenance Base. Just tugging on the torque tubes is not satisfactory..there needs to be a backup plan; this kind of incident has happened too much.

Data retrieved from NASA's ASRS site as of April 2012 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	960710
Time
Date	201107
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	Regional Jet 700 ER/LR (CRJ700)
Operating Under FAR Part	Part 121
Flight Phase	Parked
Component
Aircraft Component	Flap Control (Trailing & Leading Edge)
Person 1
Function	Inspector
Qualification	Maintenance Airframe Maintenance Powerplant
Person 2
Function	Technician
Qualification	Maintenance Powerplant Maintenance Airframe
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy

A mechanic and inspector assert crj-700 maintenance procedures are not satisfactory for verifying flap torque tube locking bolts are properly engaged with flap actuator drive spline shafts. A crj-700 flight crew had received a flap warning in flight. Flap torque tube found disconnected.