Inadvertent activation of the standby power switch when the intention was to release the lock on the...

Attributes
ACN	577326
Time
Date	200303
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : czul.artcc
State Reference	PQ
Altitude	msl bound lower : 34000 msl bound upper : 34400
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : czul.artcc
Operator	common carrier : air carrier
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	cruise : enroute altitude change
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 160 flight time total : 14000 flight time type : 800
ASRS Report	577326
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical altitude deviation : excursion from assigned altitude non adherence : published procedure non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to assigned altitude flight crew : overcame equipment problem
Supplementary
Problem Areas	Company FAA Flight Crew Human Performance Aircraft
Primary Problem	Aircraft

Narrative:

Altitude deviation. Autoplt tripped off when captain inadvertently switched standby power switch off, while reaching for the new door unlock switch. The door unlock switch and standby power switch are located adjacent to one another and look and operate the same. When autoplt tripped off, aircraft climbed 400 ft maximum before captain returned aircraft to level flight at FL340. No other aircraft was in the vicinity via TCASII. Center made no comments on altitude deviation. Other factors: copilot was returning to cockpit and captain was answering radio calls at same time. Corrective action should be to move the location of the new door open switch which was installed as a result of the new security door instability. It's position resulted in turning standby power switch off, which turned off autoplt, allowing aircraft to climb slowly before pilots sensed climb. Callback conversation with reporter revealed the following information: the switches involved are on the overhead panel, one above the other, no more than 1-2 inches apart. They are identical in description and operation. There is a company bulletin warning of the possibility of unintended activation and there have been several incidents at this company. As a result there is a program in place to install a guard for the standby power switch to prevent unintended activation.

Original NASA ASRS Text

Title: INADVERTENT ACTIVATION OF THE STANDBY PWR SWITCH WHEN THE INTENTION WAS TO RELEASE THE LOCK ON THE REINFORCED COCKPIT DOOR CAUSED THE AUTOPLT TO DISCONNECT RESULTING IN AN ALT EXCURSION WHICH WAS NOT NOTICED BECAUSE OF THE CONFUSION OF BEING PRESENTED WITH VARIOUS WARNINGS ALSO CAUSED BY THE PWR LOSS.

Narrative: ALTDEV. AUTOPLT TRIPPED OFF WHEN CAPT INADVERTENTLY SWITCHED STANDBY PWR SWITCH OFF, WHILE REACHING FOR THE NEW DOOR UNLOCK SWITCH. THE DOOR UNLOCK SWITCH AND STANDBY PWR SWITCH ARE LOCATED ADJACENT TO ONE ANOTHER AND LOOK AND OPERATE THE SAME. WHEN AUTOPLT TRIPPED OFF, ACFT CLBED 400 FT MAX BEFORE CAPT RETURNED ACFT TO LEVEL FLT AT FL340. NO OTHER ACFT WAS IN THE VICINITY VIA TCASII. CTR MADE NO COMMENTS ON ALTDEV. OTHER FACTORS: COPLT WAS RETURNING TO COCKPIT AND CAPT WAS ANSWERING RADIO CALLS AT SAME TIME. CORRECTIVE ACTION SHOULD BE TO MOVE THE LOCATION OF THE NEW DOOR OPEN SWITCH WHICH WAS INSTALLED AS A RESULT OF THE NEW SECURITY DOOR INSTABILITY. IT'S POS RESULTED IN TURNING STANDBY PWR SWITCH OFF, WHICH TURNED OFF AUTOPLT, ALLOWING ACFT TO CLB SLOWLY BEFORE PLTS SENSED CLB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE SWITCHES INVOLVED ARE ON THE OVERHEAD PANEL, ONE ABOVE THE OTHER, NO MORE THAN 1-2 INCHES APART. THEY ARE IDENTICAL IN DESCRIPTION AND OP. THERE IS A COMPANY BULLETIN WARNING OF THE POSSIBILITY OF UNINTENDED ACTIVATION AND THERE HAVE BEEN SEVERAL INCIDENTS AT THIS COMPANY. AS A RESULT THERE IS A PROGRAM IN PLACE TO INSTALL A GUARD FOR THE STANDBY PWR SWITCH TO PREVENT UNINTENDED ACTIVATION.

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.