ISO 5065-2:1986

Overview

ISO 5065-2:1986 specifies the test procedures and performance requirements for aircraft magnetic indicators (to be read with ISO 5065-1). It defines environmental, mechanical and electrical tests to verify that magnetic indicating instruments meet durability, safety and operating requirements for airborne use. The standard sets pass/fail criteria and references other avionics environmental test standards.

Key topics and requirements

The standard covers a comprehensive battery of tests and measurable performance limits, including:

• Electrical performance

  • Coil current consumption: Category 1 < 0.045 A, Category 2 < 0.030 A measured at 28 V after 1 minute.
  • Lamp currents: 0.120 ± 0.018 A (two lamps at 5 V); 0.020 ± 0.003 A (one lamp at 28 V).
  • Drop-out voltage: mobile sector must return to datum before supply falls below 3 V (and at extreme temperature tests, below 1 V).
  • Insulation resistance per ISO 2678 minimum values.

• Environmental durability

  • Thermal shock: repeated transfer between -40 °C and +90 °C, transfer time ≤ 1 min, three cycles.
  • Low/high temperature operation: functional checks at -40 °C and +90 °C (2 h each).
  • Extreme storage: -50 °C and +110 °C exposures (2 h).
  • Damp heat (humidity): ISO 7137 Category B, 240 h (10 × 24 h cycles).
  • Salt spray: 48 h per ISO 7137.
  • Temperature & altitude: operation at ± temperature with ambient pressure equivalent to 21 336 m altitude.

• Mechanical and dynamic tests

  • Life cycling: 1 × 10^6 operations with defined mounting and temperature distribution; lamps energized where fitted.
  • Vibration and steady-state acceleration per ISO 7137 / ISO 2669.
  • Mechanical shock: half-sine impulse, transmitted 15 g, 11 ± 2 ms, 18 shocks (six directions).
  • Contact tests: insertion, extraction, retention force and endurance with specified force limits and displacement criteria.
  • Sand & dust, drip, fungus resistance, and resistance to cleaning fluids (50 ± 2 °C spray for 7 days).

• Functional/visual criteria

  • No visible deterioration or functional impairment after tests.
  • Luminance: white areas 17–40 cd/m², black areas ≤ 0.34 cd/m².
  • Magnetic effect: compass safe distance ≤ 305 mm.

Applications and users

ISO 5065-2 is used by:

• Aircraft instrument and avionics manufacturers for design verification
• Test laboratories performing environmental and functional qualification
• Certification and regulatory bodies assessing equipment airworthiness
• MRO and procurement teams specifying durability and compatibility requirements

Practical benefits include standardized acceptance criteria, improved reliability in harsh flight environments, and clearer evidence for certification and supplier evaluation.

Related standards

• ISO 5065-1 (characteristics for magnetic indicators)
• ISO 2678 (insulation resistance / high voltage tests)
• ISO 2669 (steady-state acceleration)
• ISO 7137 (environmental conditions and test procedures for airborne equipment)

Keywords: ISO 5065-2:1986, aircraft magnetic indicators tests, environmental testing for aircraft equipment, insulation resistance, vibration testing, thermal shock.