DS-3M2

Fire alarm / smoke detector DS-3M2

The smoke detection system in the cargo cabin of the Il-76 / MI-171 helicopter.

The smoke detection system provides monitoring of the state of the air environment in the cargo cabin of the aircraft and notifying crew members of the appearance of smoke in it. Control over the appearance of smoke is carried out by a photoelectric smoke detector DS-3M (DS-3M2). Alert crew members about the appearance of smoke is produced using light signaling and signals from the voice information system. The smoke detection system includes smoke detectors, an alarm activation relay, a board, a switch, and a system health check button. Smoke detectors are designed to emit electrical signals when smoke appears in the cargo compartment at concentrations where the transparency of the air environment in the cabin is reduced by 30 ± 10% or more. The DS-3M signaling device (DS-3M2) is a unit in which a sensitive element is mounted (photoresistor SF2-5), an amplifying circuit at transistors and a device for monitoring the operability of a signaling device. The aircraft’s smoke detection system uses 10 DS-3M (DS-3M2) annunciators, which are installed in the upper part of the cargo compartment in the area from frame No. 17 to frame No. 63. To the elements of the airframe design.