A-69-016
NTSB Safety Recommendation — Aviation
Recommendation text
IT WAS BROUGHT TO THE ATTENTION OF THE FAA THAT THE INADVERTENT TURNING OFF OF THE BATTERY SWITCH, WHICH IS LOCATED IN PROXIMITY TO FUEL PUMP SWITCHES, COULD CAUSE COMPLETE LOSS OF ELECTRICAL POWER. THE BOARD RECOMMENDED PROVISION OF A BATTERY SWITCH SAFE-GUARD. 11/6/69 IT WAS FURTHER BROUGHT TO THE ATTENTION OF THE FAA THAT ON JUNE 19, 1969, MCDONNELL DOUGLAS ISSUED SERVICE BULLETIN NO. 24-36 STATING THAT DURING CONDITIONS OF MINIMUM LIGHTING THERE WAS POSSIBILITY OF INADVERTENTLY ACTUATING THE BATTERY SWITCH TO THE "OFF" POSITION. SHOULD THIS OCCUR, FAILURE OF THE AUXILIARY POWER UNIT COULD RESULT WITH MOMENTARY LOSS OF COCKPIT LIGHTING. A LUMINOUS BATTERY SWITCH OR LEVERLOCK WOULD ELIMINATE POSSIBILITY OF INADVERTENT ACTUATION. THE BOARD RECOMMENDED AN A.D. BE ISSUED MAKING BULLETIN MANDATORY.
In plain language (FlightFinder summary)
The FAA is asked to provide a safeguard for the battery switch, as its proximity to fuel pump switches could lead to inadvertent turning off and complete loss of electrical power. Additionally, the FAA should issue an Airworthiness Directive making McDonnell Douglas Service Bulletin No. 24-36 mandatory, since a luminous battery switch or leverlock would prevent inadvertent actuation in low lighting conditions, which could cause auxiliary power unit failure and momentary loss of cockpit lighting.
This plain-language summary is written by FlightFinder to explain the recommendation above. It is not the official wording — the verbatim NTSB text is quoted above.
Details
| Status | Closed - Unacceptable Action |
|---|---|
| Mode | Aviation |
| Closed | Jan 21, 1970 |
| NTSB number | 80505 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).