A versatile fire test has been developed with a complete set of instrumentation to investigate the fire behaviour of carbon fibre epoxy composite designed for aircraft. During a single test, both condensed and gas phases can be simultaneously studied measuring the temperature profile and the mass loss and studying the nature and quantity of volatile gaseous species. This novel test bench is compliant with two aeronautical certification fire tests: ISO2685:1998(E) and FAR25.856(b):2003. Titanium coupons have been first submitted to fire to validate the testing method. Composite coupons have been evaluated to examine completely their fire behaviour. To go further in the investigation, post-fire analyses have been performed using X-ray microtomographic images of coupons exposed to fire. Thus, the phenomena identified during the test are the apparition of cracks in the virgin material, the thermal degradation, the migration of evolved gases through the material up to both side and the thermal delamination.

After separate developments of the different elements with continuous characterizations and improvements, the LNE watt balance has been assembled. This paper describes the system in detail and gives its first measurements of the Planck's constant h. The value determined in air is h = 6.626 068 8(20) × 10 −34 Js which differs in relative terms by −0.05 × 10 −7 from the h 90 value and by −1.1 × 10 −7 from that of the 2010 CODATA adjustment of h. The relative standard uncertainty associated is 3.1 × 10 −7 .

A determination of the Planck constant h using the LNE Kibble balance in air was carried out in the spring of 2017. Substantial improvements since 2014, chiefly related to the mass standard, mechanical alignments, voltage measurements and type A evaluation uncertainties, leads to a h value of 6.626 070 41(38) × 10 -34 J • s, with a relative standard uncertainty of 5.7 × 10 -8 .

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