Temperature and Altitude – RTCA DO-160

What Is Temperature and Altitude — RTCA DO-160?

DO-160 Section 4 examines airborne equipment's behaviour under temperature and altitude conditions. The section covers low and high temperature operation and storage, altitude, decompression and overpressure procedures. Which category the equipment is subject to is determined by where it will be installed on the aircraft.

Purpose of Temperature and Altitude — RTCA DO-160

The purpose is to show the equipment maintains its declared function and sustains no permanent damage under the temperature and pressure conditions it will encounter over the flight envelope. This section is the most commonly required part of a DO-160 qualification.

Which Products Is Temperature and Altitude — RTCA DO-160 Applied To?

Avionics units and displays
Cabin electronic systems
Equipment installed in unpressurised bays
Antenna and external skin-mounted equipment
UAV mission payloads

In Which Sectors Is Temperature and Altitude — RTCA DO-160 Used?

AerospaceSpaceDefenceElectronics

Standards Related to Temperature and Altitude — RTCA DO-160

RTCA DO-160Environmental conditions and test methods in aviation equipment test

Temperature and Altitude — RTCA DO-160 Conditions

Category: The category corresponding to the equipment's installation zone on the aircraft (A1, A2, B, C, D...)
Procedures: Ground survival, short-time operating, operating temperatures, altitude, decompression, overpressure
Temperature and altitude values: From the selected category's table in the standard
Monitoring: Function is continuously monitored in the operating procedures

Equipment for Temperature and Altitude — RTCA DO-160

Climate-controlled altitude (temperature + pressure) chamber
Calibrated temperature and pressure measurement systems
Functional monitoring and load simulation rig
Data acquisition system

Sample Requirements for Temperature and Altitude — RTCA DO-160

The equipment must be supplied in the final configuration of the design being certified.
The installation zone on the aircraft and its corresponding categories must be declared.
Cable types, lengths and the connection layout must reflect the real installation.
The functional check procedure and acceptance criterion must be provided in writing.
The software version and hardware revision must be recorded.

Duration of Temperature and Altitude — RTCA DO-160

When all procedures of the section are applied, the study takes several days to a week. The time waited for the specimen to reach thermal equilibrium makes up most of the total duration.

Temperature and Altitude — RTCA DO-160 Procedure

1The equipment's installation zone and category are determined.
2A functional check is performed before the test.
3The specimen is placed in the chamber and thermocouples are attached.
4The ground survival and short-time operating procedures are applied.
5Function is verified at low and high operating temperatures.
6The altitude, decompression and overpressure procedures are applied.
7Post-test inspection and a functional check are performed.

Temperature and Altitude — RTCA DO-160 Acceptance Criteria

The severity level and acceptance criterion come not from the method standard but from the specification the product is subject to: for MIL-STD-810 applications, the product's environmental life cycle profile and procurement specification are decisive; for DO-160 applications, it is the category corresponding to the equipment's installation zone on the aircraft. This page therefore gives no numerical limit.

Evaluation of Results

The result is assessed on the equipment meeting the manufacturer-defined success criterion in each procedure. The success criterion is written in the manufacturer's functional test procedure; the standard does not define it.

Temperature and Altitude — RTCA DO-160 Report

Equipment identification, part number and configuration
Standard, revision and method/section number applied
Selected severity level or category and its basis
Test rig, mounting arrangement and measurement points
Functional checks performed before, during and after the test
Measurement results, observations and photographs
Non-conformities and any test deviations
A statement that the result applies only to the specimen submitted for testing

Accreditation

EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.

Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.

Scope and authorisations

Related Regulations

RTCA DO-160 / EUROCAE ED-14 (environmental conditions and test procedures for airborne equipment)
Certification requirements under EASA CS-25 / FAA 14 CFR Part 25
The equipment manufacturer's TSO/ETSO approval requirements

Aerospace Testing — What Does This Testing Field Cover?

The section below describes the field that the Temperature and Altitude test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.

Aerospace testing shows that equipment keeps working in the flight environment and provides evidence for the airworthiness file. In this family the acceptable probability of failure is several orders of magnitude lower than in other sectors; this directly determines the scope of testing and the certification burden.

The most distinctive feature of the field is TRACEABILITY. Which melt an aircraft part came from, in which heat treatment furnace and with which cycle it was processed, which operator made the weld and which inspector approved it are all recorded. The test report is one link in this chain; if the chain is broken, the report carries no value on its own.

Environmental qualification runs through RTCA DO-160, with categories selected according to the equipment's MOUNTING LOCATION in the aircraft. A device mounted on the cockpit panel and one mounted inside the wing pass the same section under different categories. When reading a DO-160 report it is therefore essential to know which sections were applied at which categories.

On the software and complex hardware side the approach changes entirely: the evidence is not testing but PROCESS ASSURANCE. DO-178C for software and DO-254 for complex electronic hardware define how the development process is to be run and which evidence is to be produced. Every step, from requirement to code, from testing of the code to coverage analysis, must be traceable. Testing software does not make it certifiable; the process record does.

A separate body of work applies on the material and special process side. AWS D17.1 is used for welding, SAE AMS 2750 for pyrometry in heat treatment and NAS 410 for non-destructive testing personnel. For special processes (heat treatment, coating, welding, NDT, bonding) NADCAP accreditation is effectively mandatory in the supply chain; without NADCAP it is not possible to sell parts to many OEMs.

On the quality system side the AS/EN 9100 series is used: 9100 for manufacturers, 9110 for maintenance organisations and 9120 for distributors. Without these certificates it is practically impossible to enter the aerospace supply chain, and audits are markedly more detailed than in other sectors.

Counterfeit part risk is a subject peculiar to the field. Separate standards and verification methods (visual inspection, X-ray, decapsulation and internal structure examination, XRF) are used to detect counterfeit or reworked parts in the electronic component supply chain.

Space applications add further layers: outgassing in vacuum, radiation tolerance, long-duration thermal vacuum cycling and assessment of single event effects.

Method groups in this field

Environmental qualification
RTCA DO-160 sections: temperature and altitude, vibration, shock, humidity, sand and dust, fungus, salt fog, fluid susceptibility, icing, lightning.
Electromagnetic
The EMC sections of DO-160; MIL-STD-461 and MIL-STD-704 power characteristics on military platforms.
Software and hardware assurance
DO-178C software life cycle and DO-254 hardware design assurance evidence; requirement traceability and coverage analysis.
Materials and welding
Welding qualification under AWS D17.1, mechanical testing of materials, metallography and non-destructive examination.
Special process control
SAE AMS 2750 pyrometry, coating and heat treatment process verification, preparation for NADCAP audits.
Space environment
Thermal vacuum cycling, outgassing, radiation tolerance and acoustic/vibration qualification.

Commonly confused in this field

There is no such document as a "DO-160 certificate"; DO-160 is a test specification and its output is a qualification report.
The selection of sections and categories comes from the customer's equipment specification; the laboratory cannot make that selection on its own.
DO-178C and DO-254 cannot be satisfied by testing; the evidence is the traceability of the development process.
An AS9100 certificate is not a product approval; it is a quality system certificate and part approval runs separately.
For special processes, work carried out without NADCAP is not accepted in the supply chain even when it is technically correct.
MIL-STD-810 and DO-160 are often confused: one is a military and the other a civil aviation specification, and their profiles differ.

Which decisions these results support

Airworthiness and TSO/ETSO files
Entry into the aerospace supply chain and supplier approval
Special process approval and NADCAP preparation
Determining the impact of a design change on qualification
Managing counterfeit part risk and component verification

Related Tests

Frequently Asked Questions About Temperature and Altitude — RTCA DO-160

Who determines the category?

The zone where the equipment will be installed on the aircraft determines it: a pressurised cabin, an unpressurised bay, or an external surface correspond to different categories. The choice and its justification are given in the qualification plan.

Does the standard give the success criterion?

No. DO-160 only defines the conditions and procedure; the manufacturer states, in its own functional test procedure, what behaviour of the equipment is acceptable.