A compliance testing certification should be available when using a rugged server or workstation. Rugged servers must undergo certification by an internal lab or compliance laboratory to ensure they can withstand and function as intended in harsh environments that would typically damage standard computers. These environments include desert conditions, submarine environments, or, as specified in DO-160, onboard aircraft.   

Military and commercial testing standards such as DO-160 are frequently used to ruggedize and stress-test servers for usage in difficult locations. The purpose of the DO-160 tests is to evaluate robust computers that are intended to be used in or on supersonic transports, jumbo jets, helicopters, and general aviation aircraft.  

By utilizing a robust server or workstation that holds DO-160 certification, you and your team can focus on your applications while airborne, free from concerns about potential breakdowns or malfunctions. 

What is DO-160 testing?

DO-160 is a live document that contains environmental testing requirements for aerospace industry. The official title of the document is Environmental Conditions and Airborne Equipment Test Procedures. The Radio Technical Commission for Aeronautics (RTCA) is responsible for maintaining and disseminating DO-160.  

Since its first publication in 1975, the European Aviation Safety Agency (EASA) and the U.S. Federal Aviation Administration (FAA) have embraced DO-160, despite it not being a government standard or rule.  

According to an advisory circular published by the FAA in June 2011, RTCA / DO-160 has been used as an environmental testing standard for airborne equipment since 1958, when it was known as DO-130.  

Introduced in December 2010, the latest iteration of DO-160, referred to as DO-160G, includes revisions related to test conditions, power input, and susceptibility to radio frequencies, among other factors. Although equipment installed on aircraft is not mandated to undergo DO-160 environmental testing, it has become widely accepted across the industry by equipment vendors, airlines, compliance testing institutions, and government agencies. This acknowledgment serves to establish a consensus regarding the quality and reliability standards for aviation equipment.  

Which tests are under DO-160’s purview?

23 test standards are included in DO-160:

• Standard 4- Temperature and Altitude
• Standard 5-Temperature Variation
• Standard 6- Humidity
• Standard 7- Operational Shocks and Crash Safety
• Standard 8- Vibration
• Standard 9- Explosive Atmosphere Standard 10- Waterproofness
• Standard 11- Fluids Susceptibility
• Standard 12- Sand and Dust
• Standard 13-Fungus Resistance
• Standard 14- Salt Fog
• Standard 15- Magnetic Effect
• Standard 16- Power Input
• Standard 17- Voltage Spike
• Standard 18- Audio Frequency Conducted Susceptibility – Power Inputs
• Standard 19-Induced Signal Susceptibility
• Standard 20&21- Radio Frequency Susceptibility
• Standard 20&21- Radio Frequency Susceptibility (Radiated and Conducted)
• Standard 20&21- Emission of Radio Frequency Energy
• Standard 22&23- Lightning-Induced Transient Susceptibility
• Standard 22&23- Lightning Direct Effects
• Standard 24- Icing
• Standard 25- Electrostatic Discharge
• Standard 26- Fire and Flammability

Every portion of DO-160 is customized for each customer and specifically designed to fit the equipment or rugged computing system’s intended environment.   

eInfochips has worked with the world’s top 10 commercial aircraft corporations. One of the eInfochips’ clients wanted to build an Electric Motor Control Unit (EMCU) for a leading aircraft program. Check out how eInfochips provided a DO-178B Motor Control for Horizontal Stabilizer System solution within a limited time window.  

Let’s discuss some of the test procedures mentioned above:  

Section 4 – Temperature and Altitude

Assessing equipment’s performance qualities under severe hot or cold conditions and at various altitudes is the goal of DO-160 temperature and altitude testing. There are 20 categories in this technique that cover the whole spectrum of situations known to exist in the majority of aircraft types and installation sites.  

Equipment is tested by placing it in an environmental testing room, observing its effects, and documenting the results to determine if it passed or failed.  

Section 5 – Temperature Variation

The goal of the DO-160 temperature fluctuation test is to evaluate how well the aircraft equipment performs in the event of abrupt, severe temperature variations. Five categories in this process deal with the rate of temperature change for equipment mounted in or on the aircraft.  

Similar to DO-160 Section 4, testing is carried out by putting the apparatus in an environmental testing room, keeping an eye on how the apparatus is affected, and documenting the results to decide if the apparatus passes or fails.

Section 6 – Humidity

This test is crucial because it examines how the equipment responds to variations in humidity. Humidity poses a gradual threat to materials and is detrimental to machinery. Three kinds of DO-160 equipment testing are conducted:  

• Standard Humid Environment
• Severe Humid Environment
• External Humid Environment  

Additionally, it says that this test shouldn’t be conducted before tests four and five (the order of the testing apparatus).  

To qualify: Equipment should be designed to prevent vapor formation or, if it does occur, to ensure it does not affect the essential components of the equipment. Furthermore, it is crucial to protect the components with a suitable covering.   

When designing anything that can withstand high temperatures, protective coatings, painting, and other protective treatment processes must be considered.  

The surface finish of coatings is important for vapor deposition, and it also affects the surfaces of moving components and boxes.  

Section 7 – Operational Shocks & Crash Safety

• The goal of DO-160 shock testing is to confirm that the equipment subjected to shocks during routine aircraft operations continues to operate within the specified performance criteria. Another aspect of DO-160 Section 7 is the crash safety test, aimed at ensuring that specific equipment remains securely mounted and does not pose a hazard during emergency landings.DO-160 Section 7 has four categories for equipment testing: Standard Operational Shocks (Category A), Low-Frequency Operational Shock (Category D), and Standard Operational Shock and Crash Safety (Category B). 
• An accelerometer is used to measure and regulate shock pulses when an apparatus is strapped to a shock table for testing.  

Section 8 – Vibration

When subjected to vibration levels unique to the installation, DO-160 vibration testing uses a battery of tests to prove that airborne equipment meets the durability criteria and performance standards.  

The following three tests are related to DO-160 vibration testing, and each has one or more categories: Standard (Category S), Robust (Categories R, U, and U2), and High-Level, Short-Duration (Categories H, Z).  

For fixed-wing aircraft, the Standard Vibration Test (Category S) is used. Its goal is to ascertain whether the equipment works as required in the usual vibration environment experienced during the routine aircraft operations. 

The purpose of the Robust Vibration Test (Categories R, U, and U2) is to determine whether the equipment can withstand vibration exposure and continue to function even after being exposed to endurance vibration levels.  

The Robust Vibration Test is defined by DO-160 as a combined evaluation used to monitor the structural integrity and operational performance of the equipment.  

The Robust Vibration Test encompasses testing protocols for equipment installed in helicopters and is best suited for equipment subjected to prolonged vibration exposure.  

The High-Level, Short-Duration Vibration Test is recommended for equipment where a loss of function could adversely impact the aircraft’s performance. This test is specifically designed to simulate vibration conditions following an engine fan blade failure. 

Section 10 – Waterproofness

These tests ensure that the test object functions properly in settings where water is pouring or spraying. The equipment’s ability to withstand liquid entry is determined by the RTCA DO-160 waterproofness test standard. The liquid can enter the equipment in a few distinct ways. The most noticeable is the mist. Condensation and dripping liquid are the two other ways that water can enter the equipment.  

Four main kinds of equipment are specified in the DO-160 Section 10 test standard.  

Category Y 

Equipment placed in areas where it comes into contact with condensing water during routine airplane operations.

Category W 

Equipment placed in areas where it occasionally gets exposed to falling water during routine aircraft operations (usually as a consequence of condensation).

Category R 

Equipment placed in locations where it may be sprayed with water from all directions or exposed to a driving rainstorm.

Category S 

Equipment placed in areas where it could be exposed to the forces of a strong stream of liquid, such as during cleaning, washing, or de-icing of aircraft.

Section 11 – Fluids Susceptibility

These tests establish whether the equipment’s building components are resistant to the harmful impacts of fluid pollutants.   

Testing for fluid susceptibility should only be done if the equipment is placed in locations where fluid contamination is likely to occur.   

The fluids are typical and often utilized in both ground and aerial operations.

Conclusion

The extensive variety of environmental conditions and testing covered by the DO-160 standard enables the detection of any flaws in electronic equipment and their timely correction prior to onboard usage.  

Since it is widely used in the aviation sector and has worldwide recognition, electronic equipment that complies with this standard is frequently accepted readily by certifying authorities and consumers.  

eInfochips provides test engineering services for both software and hardware. We work with our clients throughout the whole process, from test planning (PSAC), test case generation, and test execution to certification utilizing Run For Score (RFS) test execution and SOI audit support capacity. We provide test engineering services for Environmental Test Procedures and EMI Test Procedure document development, RTCA DO-160F, DO-160G, and MIL-Standards. The engineering services provided by eInfochips comply with ARP4754, DO-178B/C, DO-160, and DO-254.