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We provide Systems Fire Protection testing using our oil burner. Materials testing for Seat Cushions, Cargo liners and insulation and Flammability testing for all your material needs.
John Doe, Acme Co.
Resonate Testing provide a complete range of AC20-135 ISO2685 compliant propulsion level fire testing for large airplanes (FAR25, CS25, CAR525) Aircraft engines (FAR 33, CS-E, CAR 533), Helicopter (FAR27, CS27, CAR527 / FAR29, CS29, CAR529), small airplanes (FAR23, CS23, CAR523) etc. Testing includes propulsion systems and externals including structures, seals, TRU’s and a wide range of fluid and electrical systems.
Using both approved Kerosene burners and Sonic Burners we support a range of R&D, product development, and validation including certification level testing. We are happy to work to customer Qualification Test Procedures (QTP’s), although increasing clients realise significant benefits from discussing their requirements and compliance means with our engineers.
They are varied and complexity arises due to differing requirements and subsequent interpretation of a means of compliance.
The approaches are similar and seek to achieve an appropriate level of testing for the testing to demonstrate compliance with national and international airworthiness requirements, i,e FAA EASA, Transport Canada, JCAB, ENAC etc.
Various test methods, advisories and guides are used to provide criteria used in determining the flame characteristics required to test various components used in aircraft engines, their nacelles and their other supporting structures.
ISO2685: Environmental Test Procedures for Airborne Equipment – Resistance to Fire in Designated Fire Zones, International Standards Organisation
AC 20-135: Powerplant Installation and Propulsion System Component Fire Protection Test Methods, Standards and Criteria, Revised 1990 – NOTE AC 20-135:Change 1
FAA Power Plant Engineering Report No. 3A: Standard Fire Test Apparatus and Procedure (For Flexible Hose Assemblies), Revised March 1978
FAA Aircraft Material Fire Test Handbook: Chapter 11 Powerplant Hose Assemblies Test and Chapter 12 Powerplant Fire Penetration Test - used to determine the fire resistance components used in designated fire zones to damage due to flame and vibration for showing compliance with TSO C42, C53A, and C75. April 2000.
SAE AIR 1377A: Fire Test Equipment for Flexible Hose and Tube Assemblies, Revised January 1980.
SAE AS 1055: Fire Testing of Flexible Hose, Tube Assemblies, Coils, Fittings and Similar System Components, Revised 1978.
AS4273: Fire Testing of Fluid Handling Components for Aircraft Engines and Aircraft Engine Installations
RTCA DO -160G: Environmental Conditions and Test Procedures for Airborne Equipment Section 26.0 Fire, Flammability.
SAE ARP5757: Fire Guidelines for Engine Component Tests Section 5.24.
AC 33.17-1 33.17-1 - Fire Prevention (Cancelled)
Flame temperature– 2000°F minimum average (ISO 2685 doesn’t define this as a requirement. This is will be clarified)
What, How and Where do you measure?
Approved Equipment
Best Practice? Whose best practise?
Heat flux density >4500 Btu/hr (> 10.6 W/cm² (9.3 Btu/ft².s)
What, How and Where do you measure?
Approved Equipment
Best Practice? Whose best practise?
Almost without exception we can expect vibration
4g or 7g
Why any vibration
Primary Unit
FAA (2000F minimum Average )
± 150F) 1850F-2150F
2012F Note No minimum average )
(1868F- 2156F )
Note the obvious possible error 80C=176F
(1836F-2176F) Which is incorrect.
1093C min average
(1010F- 1177F )
Primary Unit
ISO2685 (1100C:
Note No minimum average )
± 80C) 1020C-1180C
Resonate are almost exclusively asked to calibrate at 1” above Centreline.
ISO2685 sketches may be misleading and be interpretated as 1” below the centre line. Due to flame buoyancy, typically flame temp is measured 1” (25.4mm) above the cone centreline.
Vertical Burner orientation and AS1055/ AS1377 define testing require flame calibration along the centreline of the cone.
Comparison of Burner Calibration- 1” above centre line Centre line.
What would the map look like with 2000F min average and ≥4500 BTU/Hr?
Comparative assessment of flame temperature with Cone, Area and Temp
Mapping Engineering Report 3A CARLIN 200 CRD Mapping and Calibration.
While the requirement is clearly 2000 F Min Average, the re-evaluation of the incumbent kerosene burners did not demonstrate compliance with this requirement.
7 type K thermocouples
1-inch apart (25mm)
1-inch above centreline
4-inches away from cone
3mm external sheath
4-6mm exposed tip
24 AWG (0.5mm) wire
Comparison of Thermocouple requires with Engineering report 3A, AC20-135, ISO2685 and FAA Fire etst handbook.
TC Requirements from the standards ISO2685 and AC20-135
Type K thermocouples are being used at the top end of their range
The actual specified thermocouples are not available, and the thermocouple industry has moved away from this definition
Exposed tip thermocouple, while giving fast response time and therefore a more accurate representation of the flame temperature have a finite life and should be replaced often
Thermocouples should be specified to meet international standard for their manufacture to ensure consistency and a minimum accuracy
Age has the biggest impact of the temperature measurement
The thermocouple reading temperature maybe significantly lower than the theoretical gas (flame) temperature in the high-temperature environment
A smaller TC indicates a higher TC temperature and provides quicker response time than the bigger TC
Resonate testing draws clients to AC No: 21-16G - RTCA Document DO-160 versions D, E, F, and G, “Environmental Conditions and Test Procedures for Airborne Equipment”. Caution is advised in light of the following clarification
h. RTCA/DO-160F, Section 26, Fire, Flammability, is not sufficient for 14 CFR parts 25 and 33. RTCA/DO-160G, Section 26, is sufficient for 14 CFR part 25 but not for 14 CFR part 33. Fire and flammability guidance for 14 CFR part 33 is provided in the latest revision of AC 33.17-1
