Re BIK
HMRC current practice is to assume the helicopter is available for use of the director unless you prove otherwise.
BIK calculated as 20% of the value of machine when first made available to anyone as a BIK plus running costs. Then pro-Rata reduce for time not available - maintenance and other hires - then reduce for any contributions that you actually made for your flight time.
That may seem unfair, as available hrs included any time it sits idle and no-one is using it but that is how the calc works.
Also be wary of VAT issues
John