A line mechanic reports both engine fire bottles fired on a crj-200 aircraft even though he had not ...

Narrative:

I was called out to a crj-200 aircraft for the engine fire bottles armed switches illuminated with power off the aircraft. I was on the aircraft to investigate the problem and did not have any trouble shooting procedures with me and was only trying to find out what the initial problem was. The push-to-arm switches were not selected and when I wiggled the left switch the [flight] crew who were standing in the jet way commented they heard something. At the same time they commented; both armed-to-discharge lights extinguished. Both bottles fired. I had not pulled the circuit breakers prior to wiggling the switch.maintenance control commented to me on the phone that the aircraft has some history; and that on the ground that both bottles will fire. No one else was on the aircraft; the flight crew was in the jet way. Before doing anything to the fire extinguishing system I will make sure all the breakers are pulled.

Original NASA ASRS Text

Title: A Line Mechanic reports both engine fire bottles fired on a CRJ-200 aircraft even though he had not selected the Push-to-Arm switches. Maintenance Control had later informed him the aircraft had some history of both engine fire bottles discharging while on the ground.

Narrative: I was called out to a CRJ-200 aircraft for the engine Fire Bottles Armed switches illuminated with power off the aircraft. I was on the aircraft to investigate the problem and did not have any trouble shooting procedures with me and was only trying to find out what the initial problem was. The Push-to-Arm switches were not selected and when I wiggled the left switch the [Flight] Crew who were standing in the jet way commented they heard something. At the same time they commented; both Armed-to-Discharge lights extinguished. Both bottles fired. I had not pulled the circuit breakers prior to wiggling the switch.Maintenance Control commented to me on the phone that the aircraft has some history; and that on the ground that both bottles will fire. No one else was on the aircraft; the Flight Crew was in the jet way. Before doing anything to the fire extinguishing system I will make sure all the breakers are pulled.

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	886214
Time
Date	201004
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	Regional Jet CL65 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Parked
Component
Aircraft Component	Powerplant Fire Extinguishing
Person 1
Function	Technician
Qualification	Maintenance Airframe Maintenance Powerplant
Events
Anomaly	Deviation - Procedural Maintenance

A line mechanic reports both engine fire bottles fired on a crj-200 aircraft even though he had not selected the push-to-arm switches. Maintenance control had later informed him the aircraft had some history of both engine fire bottles discharging while on the ground.