Taxation was defined years ago at getting the maximum milk for the minimum moo
Govts love VAT type taxes - they're really cheap to collect and the evasion is very low as it's in everyone's interest (except the last man in the chain) - to account for it
As with the UK and everywhere else now knows you get what you pay for - and all we can expect are for all taxes to rise to pay for the CV-19 crisis and the more robust health care systems people will want down the road. APD is just another revenue tax - occasionally it's dressed up as a "green" tax but really it's not. A green tax would be to tax aviation fuel at the same rates as petrol & diesel for other vehicles - and that would REALLY impact airlines