The BBC spent £310,000 on private detectives over a six-year period, the Leveson Inquiry has heard.
The corporation once used investigator Steve Whittamore, who was later convicted of illegally accessing personal data, to check whether someone was on a particular flight.
On another occasion a BBC journalist commissioned a private detective to find out the owner of a car from its number plate after the vehicle was used by someone suspected of involvement in a serious criminal conspiracy, the inquiry heard.
BBC director-general Mark Thompson told the press standards inquiry that the corporation's staff used investigators 232 times between January 2005 and July 2011 at a total cost of £310,000.
News accounted for 43 of these occasions, at a cost of £174,500, excluding the use of private security teams.
BBC Vision, which produces the corporation's TV programmes, was behind the remaining 189, spending about £133,000, in most cases for consumer shows.
The inquiry heard there were two mentions of the BBC in the documents seized in the investigation into Whittamore's activities known as Operation Motorman.
In 2001 a current affairs journalist commissioned Whittamore to supply information about whether a paedophile was on a flight into Heathrow Airport. The programme, which for other reasons was never broadcast, was looking at whether people with UK convictions for child sex offences could get jobs giving them access to children in other countries.
Mr Thompson said: "The request to try and find out whether this particular paedophile was on the aircraft, I would regard as being justified in the public interest."
The inquiry heard that Mr Thompson commissioned a wide-ranging review of the BBC's editorial practices last July, covering phone hacking, "blagging" information, paying police and other public officials for information and the use of private detectives. It found no evidence that any of the corporation's staff had hacked phones or made improper payments to police officers.
