Can you justify flying?
It depends, to whom are you justifying it?
I gave up flying 34 years ago because, with a young family and rapidly rising fuel prices, I couldn't justify it to myself.
Then, after 23 years of aching everytime I saw an aeroplane fly over, I started again, with great encouragement from my wife and family. I'm now eating into the family inheritance at a rate which, if divided amongst the five of them, would make very little difference to their lives. And they actually seem to enjoy having and old Dad who can take them and their friends flying occasionally.
So, it provides immense enjoyment to me, some enjoyment to those close to me, and I will continue as long as it does both of those things or until the money or health runs out (thanks to the NPPL that should last a bit longer).
One of several benefits of being old is that there is no point in saving money for the future. You haven't got one.