Pro pilot …
As others have said, you’re never too old to learn, provided you’re still willing to apply yourself.
There are lots of regulatory obstacles to earning money flying as a side job. And the industry at that level is on it’s ass. Don’t count on that angle to defray your costs.
There are many oddball full-time flying gigs outisde the airlines. I don’t know enough about that part of the industry to comment intelligently. Except to say that the number of helo pilots the Army produces each year far exceeds the number the civilian helo industry can absorb. Right now many/most Army guys/gals are stuck inside & can’t leave the Army even if they want to. As hostilities wind down they’re gonna get dumped on the market en masse. So whatever you’re thinking about as a second career, helo pilot ain’t it.
As to airlines …
If you’re 45 and could hire on tomorrow, you could work as an airline pilot for 20 years before you hit the current mandatory retirement age of 65. That’s enough time to make some real money at it.
But as others have noted, the airline industry is a tough thing to get into. Trying to do the traditional *bootstrap yourself to regional airline pilot *will take 3-7 years and put you $50K in debt, plus all the money you won’t earn over those 3-7 years at whatever job you do now. Newbie RJ drivers qualify for food stamps. 5 years later they’re either stuck there making 75K / year as a Captain or they’ve jumped to the majors, also making 75K/year but as an First Officer (copilot).
If they get trapped at the regionals, game over income-wise. It’s like being a permanent minor-league ball player. Same bat, same ball, same uniform. Utterly different payback.
Somebody who does get on at the majors has a shot at the bigger bucks, but even that’s not the awesome deal it once was.
There will be a tremendous retirement boom in the next 5 to 15 years. Something significant will have to change or the commercial jet industry will simply run out of pilots. My bet is a combo of high fuel prices, reduced middle-class income in America and crowded skies will simply kill off the RJ fleets and we’ll be back to the industry kinda like it was in 1980s. The smaller airports will have 2 flights per day by each of 3 or 4 major airlines flying 737-sized aircraft and that’s it. The current situation of half-hourly departures all day long from the likes of Des Moines with 2 pilots carrying 30 passengers at a time will be a thing of the past.
My take is you’re just a little too old to really get the benefit of the revolution though. You’d be more likely to be left on the cutting room floor once the cutting starts
My advice: Go do it because it’s fun. Try it for a couple hundred bucks and if you’re bitten by the bug, it’ll be $3K or 5K or 8K well spent. You’ll always wonder if you don’t.