Two line mechanics report that a B737-800 aircraft experienced moderate buffeting through the aircra...

Attributes
ACN	1019072
Time
Date	201206
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Dawn
Aircraft 1
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	Initial Climb
Component
Aircraft Component	Cowling
Person 1
Function	Technician
Qualification	Maintenance Airframe Maintenance Powerplant
Person 2
Function	Other / Unknown
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy

Narrative:

Upon departure the flight crew had #1 engine generator [idg] fall 'off-line' and had moderate vibration through the B737-800 aircraft; causing an air interruption. Upon landing and going into reverse thrust; the outboard fan cowl was blown off.heavy workload; worked three overnight aircraft. Aircraft X had two grounding items. Number one engine outboard fan cowl was opened to troubleshoot one grounding item. Gave information to lead mechanic to relay information to technical [support] for disposition. Shifted focus to third overnight check that just arrived on the gate. Grounding item on the aircraft was subsequently deferred and no further action was required. Suspect fan cowl was not properly secured.

Original NASA ASRS Text

Title: Two Line Mechanics report that a B737-800 aircraft experienced moderate buffeting through the aircraft after departure; requiring an air turn-back. On landing; while going into reverse thrust; the #1 Engine Generator had fallen 'Off-Line' as the Outboard (O/B) fan cowl was blown off the same engine.

Narrative: Upon departure the flight crew had #1 Engine Generator [IDG] fall 'off-line' and had moderate vibration through the B737-800 aircraft; causing an air interruption. Upon landing and going into reverse thrust; the outboard fan cowl was blown off.Heavy workload; worked three overnight aircraft. Aircraft X had two grounding items. Number one engine outboard fan cowl was opened to troubleshoot one grounding item. Gave information to Lead Mechanic to relay information to Technical [Support] for disposition. Shifted focus to third Overnight Check that just arrived on the gate. Grounding item on the aircraft was subsequently deferred and no further action was required. Suspect fan cowl was not properly secured.

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.