A-70-026
NTSB Safety Recommendation — Aviation
Recommendation text
THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION TAKE THE FOLLOWING ACTION TO IMPROVE THE CAPABILITIES OF THE CVR: 1. IMPROVE THE COCKPIT AREA MICROPHONE CAPABILITY BY REQUIRING THE INSTALLATION OF TWO ADDITIONAL SMALL DIRECTIONAL MICROPHONES MOUNTED BENEATH THE INSTRUMENT PANEL GLARE SHIELD, AS A SINGLE OR DUAL UNIT, WITH ONE DIRECTED TOWARD THE CAPTAIN AND THE OTHER TOWARD THE FIRST OFFICER. A SMALL ELECTRONIC SWITCHING NETWORK WITH AN ASSOCIATED SYNCHRONIZATION SIGNAL CAN BE EMPLOYED TO ADAPT THIS NEW INSTALLATION TO THE SINGLE TRACK RECORDING CAPABILITY OF THE EXISTING COCKPIT AREA MICROPHONE CHANNEL. THE PRESENT AREA MICROPHONE WOULD CONTINUE TO PROVIDE PICKUP FOR OTHER SOUNDS WITHIN THE COCKPIT. THIS TYPE OF INSTALLATION WILL ENHANCE SPEECH INTELLIGIBILITY AND PROVIDE MORE POSITIVE VOICE IDENTIFICATION. 2. ISSUE AN AIRWORTHINESS DIRECTIVE DEFINING THE ACCELERATION LIMITS AND THE PLANE ORIENTATION OF ALL IMPACT SWITCHES EMPLOYED TO COMPLY WITH FAR 25.1457. THESE SWITCHES SHOULD BE SENSITIVE TO FORCES IN THE LONGITUDINAL PLANE ONLY. 3. IMPROVE THE UNDERWATER VISUAL IDENTIFICATION OF THE CVR AND FLIGHT DATA RECORDER BY REQUIRING EXTERNAL REFLECTIVE STRIPING SUCH AS SCOTCHLITE, WHICH CAN BE DEFINED ON A BLACK AND WHITE TELEVISION CAMERA. 4. PRESERVE THE INTELLIGENCE GATHERED BY REQUIRING REPLACEMENT OF ALL RANDOM TAPE STORAGE MAGAZINES WITH A METHOD WHICH WILL PROVIDE TAPE PROTECTION SIMILAR TO THAT AFFORDED BY THE REEL STORAGE METHOD. 5. INSURE THE OPERATION OF THE CVR DURING ALL EMERGENCY SITUATIONS BY REQUIRING THE AVAILABILITY OF AN INDEPENDENT POWER SOURCE FOR THE CVR WHEN THE AIRCRAFT ELECTRICAL SYSTEM FAILS. 6. CONTINUE THE INVESTIGATION OF THE STATE OF THE ART IN FIRE PROTECTION MATERIAL IN AN EFFORT TO UPGRADE THE PROTECTION NOW AFFORDED THE CVR MAGNETIC TAPES.
In plain language (FlightFinder summary)
The NTSB urges the FAA to enhance cockpit voice recorders by adding specific microphones for better speech clarity and requiring independent power sources to ensure recording during electrical failures. The agency should also update safety standards to define impact switch limits, mandate reflective markings for easier underwater recovery, and protect data storage from physical damage and fire.
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 - Acceptable Action |
|---|---|
| Mode | Aviation |
| Closed | Mar 10, 1977 |
| NTSB number | 80453 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).