I used to believe that Concorde's nose was used to drink water with when it was thirsty.
This 'factoid' remained uncorrected in my 'mental fact archive' until the age of 20 when watching an airshow on the TV.
I remember seeing Concorde coming in to land with it's nose bent down and thinking "Ah - it'll be having a drink after it's landed.... EHHH???? WTF???"
Thanks Dad for telling me that when watching an airshow on the TV when I was 4......
A childhood belief about aeroplanes

others believed things like this
- I used to think that if you mixed a diet drink with a regular drink, it would explode. Anon
- that sneezes were caused by little pixies crawling up your nose and brushing past your nose hairs— Joanna
- My mother used ot tell me that if I picked my nose the 'Nose Spider' would bite my finger off.— Melanie
- When I was in Kindergarten I was told if I picked my nose my nose will go into eternal bleeding— Sam
- My grandparents always told me that if I picked my nose too much, my nose would get bigger.— The Mortal Elf
- My mum used to tell me that you couldn't drink water out of the tap from the bathroom as it was poisonous.Anon