UBSH-1-4-4

Meaning of the UBSH-1-4-4 designation

The designation UBSH-1-4-4 identifies the type and basic configuration of the bottle. “UBSH” refers to a unified spherical bottle. The first digit indicates the spherical body type, the second digit indicates the bottle capacity, and the final digit indicates the number of release heads or outlets used in the fire-extinguishing system. In practical supply terms, this designation is important because a similar bottle with a different number of heads or another body configuration may not match the aircraft fire-extinguishing layout.

UBSH-1-4-4 with halon extinguishing charge

The UBSH-1-4-4 is charged with halon-type extinguishing agent, depending on execution and aircraft documentation. Common charges include 114B2 or 13B1. The charge mass depends on the agent used, so the bottle should always be identified by passport, label and aircraft system requirement. The agent is pressurized by a dry gas medium, usually dried air or nitrogen. Correct charge mass and pressure are critical for system performance, because the protected compartments depend on the bottle delivering the required amount of agent through the distribution pipelines.

Release heads and protected zones of UBSH-1-4-4

The UBSH-1-4-4 configuration includes four release heads, which allows the extinguishing agent to be routed to different protected zones or discharge stages according to the aircraft system layout. The heads are normally connected with aircraft fire-protection control circuits and distribution manifolds. On helicopter applications, these protected zones may include left and right engine compartments, main gearbox area, auxiliary power unit compartment or heater area. The exact routing depends on the aircraft model and modification.

UBSH-1-4-4 on Mi-8 / Mi-17 family helicopters

On Mi-8, Mi-17, Mi-171 and related helicopters, UBSH-1-4-4 bottles may be part of the fixed onboard fire-extinguishing system. The bottle is mounted in a dedicated technical compartment, while pipelines carry the extinguishing agent to the protected areas. This installation keeps the bottle outside the most likely fire zone, while the discharge network reaches engine, gearbox, APU or heater compartments. The same general bottle type may also be found on Mi-24, Mi-26, Ka-32 and some An-family aircraft, depending on configuration.

Installation and service checks for UBSH-1-4-4

The UBSH-1-4-4 should be checked as a complete fire-extinguishing bottle assembly, not only as an empty pressure vessel. Maintenance attention normally goes to bottle condition, charge marking, pressure, safety membrane, release heads, fittings, threaded connections, brackets, pipeline outlets and passport validity. Because the bottle works under high pressure and belongs to fire-protection equipment, its service status, charging record and documentation are essential. A bottle without confirmed charge and documentation should not be treated as ready for aircraft installation.

Supply and identification of UBSH-1-4-4

When ordering the UBSH-1-4-4, the full designation should be stated together with the required extinguishing agent, number of heads, charge condition and aircraft type. It is also important to specify whether the unit is required empty, charged, with release heads installed, with passport, after inspection, or as part of a larger fire-extinguishing kit. For aircraft supply, compatibility should be checked against the aircraft parts catalog, fire-extinguishing system diagram and technical documentation for the specific aircraft modification.

Related system equipment: 1-2-4-210, PGKts, OR1-2.0-20-30. These positions are grouped by system function and installation context, not as interchangeable replacements.

Confirmed installation context includes Mi-8 / Mi-17 family helicopters. The exact execution and installation position must be checked against the illustrated parts catalogue and documentation for the specific aircraft.