A dose of reality may be just the ticket. Obviously it's very easy to focus on the, "here is the loan, and here is what I will earn when I get a job" e.g. the business plan that goes to the bank and if all goes well.
However there is a more important document which I think everyone's needs to do but not enough do.
The worst case scenario. There are people who were sponsored prior 9/11, the inevitable happened and obviously sponsorships went down the toilet and sponsored or not people found themselves several grand down, debted up to the eye balls and no pilot job.
Many of the younger people today (not all) are not so in touch with historical high interest rates. We have spent the last few years of lowering interest rates and rising property markets etc that so many people now are more than happy to borrow borrow borrow without planning for the "what ifs".
Take the following illustration for example....
Borrow £70,000
Interest 2% above base.
Term 11 years - (HSBC term)
Now this is the sort of numbers I had to think about when I started a full time Integrated course (not sponsored though) so based on todays numbers:
Base 4.75% so initial loan calculations 6.75%
Borrow £70,000, term 132 months = £752.74 per month repayments.
loan calc
So one has to plan on how you would raise that revenue if you
dont get a job after the training. £9K a year in repayments. Allowing for tax and national Insurance (1.3 factor) means that would have to be on a salary of approx £12k p.a. and that's just for the repayments. Never mind living costs on top of that.
Assuming the base rate increases another 1.5% whilst he's training (which I personally can see happening, doesn't matter if it doesn't must plan for worst case), that 11Kpa becomes 12-13k etc.
Now I know you know all of this and can probably recall terribly high interest rates of the 80's (ouch 15%) but he probably cant.
If I was you I would think very hard about being a guarantor or even considering your house as part of the security if your son cant be bothered to draw a business plan yet alone a contingency plan. A dose of reality I think is just the ticket, a lot of people being churned out the system at present are not walking into jobs and have to take non pilot forms of employment just to repay the bank.
If he is not serious about it, then would he be serious to his financial commitment, doesn't sound like it, which overall would result in you losing out if he defaults. I know it's horrible to think like that and I too would want to help if I was in your situation but perhaps it's a case of you have to be cruel to be kind.
All the best FS