I need to make a "Biggles" hat

[SoupDragon]

Fresh from my success at making a jesters hat, I need to make a WW2 flying hat, you know the sort: ear flaps, goggles, Biggles...
I do have the goggles, thankfully, I just need to make the hat.

I cant find a free pattern online, can anyone help?

Are you making it out of leather?

Could you adapt a basic skull cap pattern?

this

maybe?

I'll probably have to make it out of felt as
I cant find any brown leatherette. that pattern has potential, thanks.