1-4-1-370 OST1 13818-81

Function within the An-2 fuel system

In service, the hose forms part of the route that transfers aviation fuel between connected system components. Its flexible body permits limited relative movement while the end fittings maintain a sealed mechanical connection. This helps isolate vibration and reduces the risk of loading adjacent rigid pipelines. The exact installation point for drawing 181304-5U-04-033 should be confirmed from the An-2 fuel-system diagram or illustrated parts documentation.

The hose must not be treated as a general-purpose rubber line. Correct operation depends on compatibility with the working medium, pressure class, temperature conditions, fitting geometry and the surrounding installation. Routing must avoid twisting, excessive bending, abrasion against the airframe, contact with sharp edges and exposure to heat beyond the limits established for the assembly. Clamps and neighbouring pipelines should be checked at the same time as the hose.

Construction according to OST 1 13818-81

OST 1 13818-81 belongs to a group of aviation standards covering reinforced rubber hoses with connection fittings for aircraft, helicopter and ground-support systems. The standard family includes multiple pressure and construction classes. For that reason, its general scope of 1.5–12 MPa must not be interpreted as the exact working pressure of 1-4-1-370. The pressure rating for this precise configuration must be taken from the product passport, drawing or approved aircraft maintenance documentation.

The assembly is described as a reinforced flexible aviation hose fitted with metal end connections. Reinforcement supports the rubber body against pressure and mechanical loads, while the attached fittings provide a repeatable interface with the aircraft pipeline. The materials, internal diameter, fitting thread, proof pressure, minimum bend radius and temperature range for this part number were not reliably confirmed in open sources and should not be inferred from a neighbouring hose designation.

Installation and maintenance checks

During installation, the 370 mm length should be verified without stretching the hose or forcing the fittings into alignment. The assembly should follow its intended route with a smooth bend and sufficient clearance throughout the operating range of nearby components. Tightening must follow the applicable maintenance instructions so that the fitting is secure without rotating or damaging the flexible section. Protective caps should remain in place until the hose is ready to be connected.

Inspection should include the rubber surface, reinforcement area, ferrules and connection fittings. Cracks, hardening, swelling, cuts, exposed reinforcement, corrosion, loose fittings or evidence of leakage require evaluation under the approved maintenance procedure. The manufacturing date, storage history and permitted service life should also be checked when documentation is available. A visually similar hose should not be installed solely because its length appears to match.

Identification, related hoses and ordering

This position is included in the Aviamisto Hoses for An-2 category. Related catalogue positions: 1-4-1-500 OST1 13818-81; 1-4-1-540 OST1 13818-81; 1-4-1-780 OST1 13818-81; 1-6-1-370 OST1 13814-81. These links support catalogue navigation and do not indicate confirmed interchangeability.

For a supply enquiry, specify the complete part number 1-4-1-370, drawing 181304-5U-04-033, required quantity and documentation requirements. If possible, provide photographs of the removed hose, its markings and both end fittings. Interchangeability, fitting configuration and applicability to a particular An-2 modification should be approved against the aircraft records before the component is accepted for installation.