THE rescue of a man who set out for a bushwalk with only potatoes, naan bread and matches is likely to have cost the state $10,000.

A 29-year-old Victorian man planned to cross the Blue Mountains in just three days but came unstuck after injuring his ankle.

A search operation was launched on Wednesday after he failed to meet friends at a pre-designated rendezvous point.

''He endeavoured to walk what was, for a person equipped with ample provisions, [a] seven-day plus [hike],'' said Inspector Max Wallace from Katoomba police. ''He lacked all those essential preparations.''

Police found the man with one kilogram of potatoes and naan bread in his backpack after he lit a fire to attract the attention of two helicopters passing overhead.

Police fined the man $500 for risking his own safety and that of others. A police spokesman said it was only the second such fine issued this year.

Police refused to comment on the cost of the rescue but typically charge between $2500 and $3300 per hour for use of helicopters for non-police matters, according to a schedule of fees. Similar missions in other states have been estimated to cost between $10,000 and $12,000 an hour.

The helicopters - understood to have spent hours in the air - were supported by State Emergency Service volunteers and NSW Volunteer Rescue Association members, who battled fading light in a three-hour search.

Previous calls to bill unprepared or negligent bushwalkers for the full cost of their rescues have been dismissed as impractical because the costs are often in the tens of thousands of dollars.

A former president of Bushwalking Australia, David Reid, said charging hikers for their rescue could prove harmful.

''To introduce a broad-based penalty for people who get into trouble could well deter them from seeking assistance when it's important to do so,'' he said.

The NSW Volunteer Rescue Association commissioner, Mark Gibson, said many searches would be prevented if all bushwalkers carried locator beacons.

Last year, about 1700 beacons were triggered.