Regulatory requirements did not ensure that aircraft lighting was adequate to conduct night vision imaging system winching operations safely.
New regulatory guidance regarding the type of external white lighting should significantly reduce the likelihood of an operator using inadequate external lighting. This should reduce the likelihood of a pilots losing visual cues leading to a loss of control and collision with terrain while conducting NVIS operations. The post-safety action risk assessment results in 'acceptable'.
Substantive changes have been drafted for version 1.2 of the NVIS Multi-Part AC 91-13. CASA advised that the changes are complete and were reviewed at the NVIS technical working group on 9 November 2022.
The ATSB welcomes CASA’s proposed changes to the NVIS Multi-Part AC. In particular, guidance on the type of searchlight fitted and the quantitative guidance regarding their capabilities. Once V1.2 of the AC is published, it should be less likely that operators will use inferior lights as searchlights, resulting in greater available illumination.
As the revised AC had not been published at the time of writing, the ATSB will continue to monitor the safety issue.
Regarding the safety issue for CASA, AO-2021-018-SI-01, which involves the proactive safety action to update Multi-Part AC 91-13, 133-09 and 138-06, I can advise that the revised version 1.2 of this AC was published last month and is available on the CASA website -
https://www.casa.gov.au/sites/default/files/2022-01/advisory-circular-multi-parts-91-13-133-09-
138-06-night-vision-imaging-helicopters.PDF.
On 10 July ATSB was advised that CASA has published Version 1.2 of the multi part advisory circular. The drafted aspects previously described by CASA were all included in the final public version of the document.
