The DO-160 standard is a comprehensive document which defines all environmental requirements for aircraft including, but not limited to, temperature, humidity, altitude and electromagnetic compatibility. This page discusses the EMC portion of this standard, which is well-delineated, and its setup is a departure from the traditional MIL-STD style. The sections of interest from an EMC perspective are as follows:
15. Magnetic Effect. This test measures the magnitude of DC magnetic field emissions generated by a component. The measurement may either be performed by determining the deflection of a compass needle, or with a Gaussmeter that has adequate resolution. Equipment classifications are based on the distance at which a given amount of deflection can occur.
16. Power Input. This test subjects the power input of the component under test to various sag and surge conditions that it might encounter being attached to the power bus on the air plane. Categories are based on the type of source powering the component and different conditions are specified, depending on whether the component under test is powered from 115 Vac (typically 400 Hz), 28 Vdc or 14 Vdc.
17. Voltage Spike. This test is similar to the CS06 test specified by MIL-STD-461, except the source impedance of the spike generator is 50 ohms. It subjects the power input of the component under test to 10 usec transient having a risetime of less than 2 usec. This test applies to both AC and DC power inputs and the amplitude of the transient is defined by either one of two categories.
18. Audio Frequency Conducted Susceptibility, Power Inputs. This test is analogous to the CS01 test specified by MIL-STD-461, however, its rationale is based on inductive coupling of power frequencies/harmonics associated with AC power distribution. Severity levels vary, based on type of source powering the component and this test applies to both AC and DC power inputs.
19. Induced Signal Susceptibility. This test is similar to the RS02 test specified by MIL-STD-461, however its scope includes not only magnetic induction due to power frequencies and transients, but also electric field coupling. Tests apply to components as well as interconnecting cables and the categories are defined by whether or not interference-free operation is required, desired or not required.
20. Radio Frequency Susceptibility (Radiated and Conducted). This test combines the RS03/103 and CS114 tests under one heading. Conducted susceptibility testing covers the frequency range from 10 kHz to 400 MHz and applies to interconnect cabling. The bulk current injection (BCI) method is used and severity levels vary widely, depending on component location and cable routing. Radiated susceptibility covers the frequency range from 100 MHz to 18 GHz, and is basically the same as the MIL-STD test technique. As with the conducted susceptibility test, severity levels vary widely.
21. Emission of Radio Frequency Energy. This test combines the conducted and radiated E-field emission tests from MIL-STD-461 under one heading. Although LISNs are specified in the test setups, this standard requires that current be measured using a clamp-on current probe. The frequency range for conducted emissions is 150 kHz to 30 MHz for power lines and 150 kHz to 100 MHz for interconnected cables. The radiated emission testing is very similar to RE02 method of 461 and covers the frequency range from 2 MHz to 6 GHz. The standard emission curves have been tailored with notches for various types of communications. Measurement bandwidths are specified, eliminating the need for narrow and broadband testing and the level of emission is determined by the location of the component and interconnecting cables with respect to receivers on the aircraft.
22 Lightning Induced Transient Susceptibility. This test simulates the effects of lightning-induced transients. It can apply to both connector pins and cables, depending on location. It uses a variety of waveforms (damped sine and inverse double-exponential) having a range of amplitudes, based on severity level which is, in turn, based on component location and cable routing.
23 Lightning Direct Effects. This test applies to externally mounted equipment (e.g., antenna, exterior lights, air data probes, external sensors, and anti-ice/de-ice equipment) and its ability to withstand a direct lightning strike. Severity level will vary depending on location.
25 Electrostatic Discharge (ESD). This requirement is very similar to the commercial ESD requirement. It uses the same human body model specified by IEC/EN 61000-4-2, which consists of a 150 pF energy storage capacitor and a 330 Ω series resistor. Both direct and indirect discharges are specified for positive and negative polarities at a level of 15 kV.
Although the severity levels for this testing can range widely, the testing is quite involved even for the most benign environments. One's requirements for meeting this standard will be a function of where the component is installed in the aircraft, the length of the component's power and I/O cabling and how that cabling may be routed.
Given the specialized nature of this standard, we recommend that you Contact Us either by phone or email so that we can review your requirements and provide you with an accurate quotation.