SIST EN 3745-205:2004

Overview

SIST EN 3745-205:2004 is a European Standard developed under the Aerospace series for fibre optic cables used in aircraft applications. This standard specifies the test method for determining the longitudinal dimensional stability of the outer sheath or jacket (if present), as well as the secondary coating or buffer of fibre optic cables and fibres used in aerospace environments. The stability of these components in terms of length changes is critical to maintaining the integrity and performance of optical fibre cables in demanding aircraft conditions.

This standard is intended to be used in conjunction with EN 3745-100, which covers general test methods for aerospace optical fibres and cables. SIST EN 3745-205:2004 addresses specific requirements for longitudinal dimensional stability and integrates with complementary standards such as EN 3745-402 for temperature cycling tests.

Key Topics

• Scope and Purpose
  Specifies a method to evaluate the dimensional behavior under conditions relevant to aerospace fibre optic cables, focusing on changes in length of the sheath or jacket and fibre coating.

• Sample Preparation
  Specimens measuring (5 ± 0.1) m are prepared by removing the outer sheath and strength members to expose fibre sections. Dimensions related to the exposed fibre length and jacket end distance are measured with high precision (± 0.1 mm).

• Measurement Procedure
  Measurements are taken before and after stripping the sheath and coatings, and repeated after a 15-minute interval to detect any immediate dimensional changes.

• Testing Methodology
  Samples undergo temperature cycling tests in accordance with EN 3745-402 to simulate real aerospace environmental conditions. Changes in dimensional measurements before and after cycling are compared against specified maximum permissible limits.

• Apparatus Requirements
  Requires precision length measuring tools capable of detecting minimal dimensional changes, suitable for aerospace-grade testing.

• Specification Details
  Product-specific parameters including number of samples, tools used for stripping, and acceptable length change thresholds must be defined in conjunction with the product or test standard.

Applications

• Aerospace Industry
  Ensures the reliability and durability of fibre optic cabling used in aircraft and spacecraft, where dimensional stability under temperature fluctuations is essential for signal integrity and mechanical performance.

• Optical Fibre Cable Manufacturing
  Provides manufacturers with standardized test methods to verify cable constructions meet dimensional stability requirements for aerospace qualifications.

• Quality Assurance and Compliance
  Enables aerospace system integrators and suppliers to validate fibre optic cable components against recognized European aerospace standards, facilitating certification and regulatory compliance.

• Research and Development
  Supports R&D efforts focused on developing improved fibre optic cables with enhanced environmental resilience, particularly related to temperature-induced dimensional changes.

Related Standards

• EN 3745-100: Aerospace series – Fibres and cables, optical, aircraft use – Test methods – Part 100: General
  Provides overarching guidelines and general testing methodologies complementary to EN 3745-205.

• EN 3745-402: Aerospace series – Fibres and cables, optical, aircraft use – Test methods – Part 402: Temperature cycling
  Defines the temperature cycling procedure that simulates aerospace environmental conditions and is integral to the dimensional stability tests in EN 3745-205.

• AECMA Standards: Developed by the European Association of Aerospace Manufacturers, ensuring harmonized industry requirements across member countries.

Keywords: SIST EN 3745-205:2004, aerospace fibre optic cables, cable longitudinal dimensional stability, fibre optic cable testing, optical cable aerospace standard, temperature cycling test, fibre optic cable sheath, optical cables aircraft use, aerospace cable standards, CEN aerospace standards.