"Becoming an A.T.P." will take you at least 1,500 flight hours... You will need to complete (at your own expense, roughly $40,000 - $50,000) your:
Private Pilot Certificate
Instrument Rating
Commercial Pilot Certificate
Multi-Engine Rating
Certified Flight Instructor
Certified Flight Instructor - Instrument
Certified Flight Instructor - Multi-Engine
Once you have all the Certificates & Ratings you will be at about 275-300 hours of total flight time and it will take you a minimum of one year if you did your training full time, at the rate you suggest you are looking at 2-3 years.
You will now need to build up your flight time, 99% of civilian pilots work as Flight Instructors. Full-Time Flight Instructors typically earn between $10,000 - $25,000 per year (and generally have no benefits such as medical insurance) and gain between 500-1000 hours per year. Plan on Instructing for at least 1.5 years, probably 2 years to be conservative. Once you have your 1,500 hours total (as well as a few other prerequisties) you can then take your ATP checkride.
Now typically people make a choice in career path, if they want to go airlines they apply to the Regional Airlines (ASA, ComAir, American Eagle, Mesa, Great Lakes, ACA, SkyWest, Mesaba), if they want to be a Corporate Pilot they would typically apply to Charter Operators...
Let's assume you want the traditional route of the airlines and say you get hired at one of the larger Regionals, Mesa Airlines (United Express, America West Express, etc...) as a Jet First Officer (they have Turbo-Props which pay less, but for simplicity let's assume the jet.) When you get hired you can expect to make somewhere around $18,000 - $20,000 your first year as a First Officer (Co-Pilot), second year will yield you in the vacinity of $27,000, 3rd year will be $30,000. All this time you will be working like a dog, possibly commuting to your domicile (base) and spending a lot of time away from your wife and 3 sons...
After 2-5 years as a First Officer (upgrades can be as long as 7 years at some companies) you may get the opportunity to upgrade to Captain. Let's say after 3.0 years as F/O you get to upgrade, for conversation sake. At this point you will be earning somewhere around $50,200 (line minimums of 76 hours/month x 12 at 4th year Captain Pay ERJ/CRJ-200)... Let's say after a year as Captain on the CRJ-200, you are moved to the CRJ-700 (slight pay increase). During year 7 of employment at Mesa you will FINALLY be back to making the $60,000 (assuming base pay, which is all that is guaranteed) that you are today...
Now let's look back at the path in a quick summary:
Primary training to get your Certificates & Ratings: 2.5 years
(assuming you working full time at your current job during your training)
Working as a CFI (Full-Time) to get 1,500 & ATP: 1.5 years
Working as a First Officer at a Regional: 3.0 years
Working as a Captain at a Regional: 3.0 years
After completing all of the above you should now be making slightly above $60,000/year (The salary you are making today).
Total Elapsed Time:
10 Years
Your age upon first making $60,000/year as a Pilot:
43 years old
Salary you would have been making in 10 years at your current job assuming simple 3.0% annual raises:
$80,635
Debt from training costs:
$40,000 - $50,000
Lost income from changing jobs from current career: -$322,095
Lost income plus additional debt burden from training -$362,095
(This is strictly salary differences and doesn't take into account the cost of lost benefits, etc.)
I realize flying can be a very rewarding career, and something people love to do. As a person in your position, I think you need to look at the realistic standpoint of things. There are a lot of younger people on this board who don't have a wife and family to support who will say "If you love it, go for it"... I am a mid-30's person with a wife and family to support, I understand the challenges you face... I don't mean to rain on your parade but want to give you a realistic view before you jump head first into something that maybe you should think twice about.
In addition, job security isn't very good in this career field, all of the above estimates do not include the possibility of unemployment at any point along your career (There are current over 10,000 pilots on furlough from just the Major airlines right now, American Airlines just announced more furloughs in coming months)... I highly suggest reading the forums here, the newspapers and other publications to better educate yourself of the state of the Aviation/Airline industry before making such an important decision...
(Disclaimer: All of the above figures are simply estimates and are used for demonstrational purposes only, a persons actual income may be less of greater than the above listed figures at any given time. Regional pay was derived from www.airlinepilotpay.com using Mesa payscales and guaranteed monthly minimums of 76 hours per month. Training cost was estimated at the lower figure of $40,000, this cost may vary depending on location and a persons ability. Time frames we assumed as moving from one job directly to another without any breaks in employment. The assumption was made that the current job would be maintained until training was 100% complete and then a full-time CFI position was accepted and the current job was terminated. Raises at the current job were calculated at 3.0% annually and did not include any bonus or promotional pay potential)