RI-65B

Automatic voice message playback by RI-65B

The main function of RI-65B is automatic playback of voice messages in response to signals from aircraft systems. These control signals may be received as DC voltage commands or pulse-type signals. Once a command is detected, the RI-65B system starts the corresponding message cycle. The message is normally reproduced twice, which improves crew recognition in noisy cockpit conditions. This is useful when the crew needs a clear spoken warning rather than only a lamp, siren or standard audio tone.

RI-65B for crew and ground notification

RI-65B informs the crew directly through the aircraft audio system and headsets. At the same time, the message can be fed to the input of the onboard radio transmitter for transmission to ground services. This makes the system useful not only for cockpit alerting, but also for communication of critical onboard situations outside the aircraft. The system is designed to maintain high speech intelligibility even in strong aircraft acoustic noise, which is especially important on helicopters and transport aircraft.

System composition of RI-65B

RI-65B is a complete voice warning system made of several main units. The RI-65-10 unit contains the recorded voice messages and provides message playback. The RI-65-20 panel is used for remote control functions. The RI-65-30 matching amplifier provides signal matching and output amplification for connected aircraft communication and audio equipment. These units work together as one system, so procurement should clearly specify whether the requirement is for the full RI-65B set or for a separate unit from the system.

Audio performance of the RI-65B system

The RI-65B system is designed for understandable speech reproduction in aircraft operating noise. The equipment provides high speech intelligibility at high cockpit noise levels and supports the required audio frequency range for spoken messages. The matching amplifier has both high-impedance and low-impedance outputs, allowing connection to different aircraft audio paths. During maintenance, audio quality should be checked by message playback, output level, distortion, frequency response, amplifier gain and correct connection to the aircraft intercom and radio equipment.

RI-65B in aircraft warning architecture

The system works as part of the aircraft warning and annunciation architecture. It receives signals from onboard warning sensors, critical-mode detectors and aircraft systems, then converts these signals into voice messages. RI-65B may also be associated with upgraded voice warning systems such as Almaz-UP, depending on the aircraft configuration and modernization documentation. Since warning logic depends on aircraft wiring and signal assignment, the message dictionary and command lines should be checked before replacement or installation.

Operating conditions of RI-65B

RI-65B is designed for severe aviation environments. The system is intended to withstand low and high ambient temperatures, vibration, shock, linear loads, high humidity, frost and dew. This is important because voice warning equipment must remain serviceable in emergency or abnormal situations, not only during comfortable ground conditions. During inspection, attention should be paid to housing condition, connectors, insulation, amplifier operation, message playback, control panel function and signs of moisture or long-term storage.

Supply and inspection of RI-65B

For procurement, the full designation RI-65B should be specified, along with the required configuration and condition. It is important to confirm whether the customer needs the complete set with RI-65-10, RI-65-20 and RI-65-30, or only one of these units. Before installation, the equipment should be checked for markings, housing condition, connectors, power consumption, message playback, amplifier output and compatibility with the target aircraft audio and warning systems. Technical passport and operating documentation should be confirmed where available.