By the time you’re eligible for hire by the airlines you’ll be 50.
Unless you have $150k laying around that’s 3 years at minimum wage.
Nobody knows what the market will be in 3 years.
If anything do this part time one rating at a time with money that you have or make as you go along.
You can quit at any time without debt if the market tanks or if you decide it’s not for you.
Please, do NOT get a $70,000 loan at 6% with your home as collateral.
By the way, my wife had 4 part time jobs when I was instructing.