"The glamour days of aviation are over."

That was the message to aspiring young pilots attending a professional training exhibition at Heathrow on Saturday, where they were warned they faced up to £120,000 worth of debt and "little prospect of a job".

The event was organised by Balpa, the trade union for pilots, and paints a stark picture of the pay and conditions facing the industry that is probably a far-cry from what most passengers envisage.

The starting salary for a newly-qualified pilot is likely to be no more than £17,000, although if they were able to accrue enough flying time this could climb to £40-50,000 within five years.

In reality, however, graduates are increasingly being recruited by airlines on a self-employed basis. These rather exotic arrangement requires them to set themselves up as limited company and then hire out their services at hourly rates of around £20-55.

Peak time earnings might be good, but of course it means no guaranteed hours, no sick pay or holiday entitlement - a boon for the airlines but a hardship for financially hamstrung recruits.

Balpa's own guide for prospective pilots warns that average training costs are £60-80,000 with none of the student loan financing available for university courses. Even the best bank loans on the market for pilot training could mean repayments of £800 a month over 11 years, depending on the interest rate.

Captain Brendan O'Neal, Balpa chairman and a pilot with 22 years experience, said: "I understand and share the enthusiasm of many young people whose dream is to walk into the cockpit as an airline pilot.

"But the reality is that it can be a difficult road to travel and I am determined that people understand the potential pitfalls as well opportunities that are out there."

A recent report for the European Commission found that one in six European pilots are now employed through a temporary work agency, self-employed or on a zero-hours contract. Casual labour is even more common among young pilots, with 40 per cent of 20-30 year olds are flying without being directly employed by their airline.

The report singled out Ryanair, Norwegian and Wizz Air among the worst offenders, although the companies have rebuffed the findings and criticised the methodology of the report which was based on an anonymous survey of 6,600 pilots.

Anyone who has seen Michael Moore's documentary, 'Capitalism: A Love Story', might be reminded of his conversations with US regional airline pilots who were mired in debt and taking up second jobs to top up their meagre earnings. Some were even on food stamps.

The situation was highlighted by black box audio from a Continental flight which crashed in Buffalo in 2009, killing all 49 on board. Moments before the crew had been discussing "how little they were paid and how overworked they were".

Much talk lately has focused on the need for mental health checks on pilots in the wake of the appalling Germanwings crash. Airlines undoubtedly have a duty of care to their staff, but surely this should also extend to pay packets and social security obligations.

If airlines can find ways to dodge these by employing pilots at arms-length, perhaps they will also expect pilots to fund their own check ups?