IN 1976 THE NAVY hired a consulting firm to study a controversial missile despite the fact that the founder of the firm also was working for the missile's manufacturer. Last year the Department of Transportation was about to spend $1.7 million hiring public-relations consultants until top agency officials pointed out that DOT has its own 300-member public-affairs staff - and canceled the consulting contracts.

Those are just two examples of the possible improprieties and waste of public funds that have resulted from the federal government's loose control of its use of consultants. Federal agencies have hired consultants to lobby for specific legislation on Capitol Hill. They've hired consultants to get around personnel ceilings or merit-system procedures. And they have hired consultants whose other affiliations conflict with the government work they're supposed to perform. How widespread are these and other abuses of the billion-dollar government-consulting business? Nobody knows. According to a recent government report, it isn't possible now to determine how many consultants federal agencies are using, at what cost and for what purposes.

In an effort to get some sort of grip on this sorry situation, the Office of Management and Budget, prompted by a Senate subcommittee's hearings and an order from President Carter, recently issued the government's first uniform guidelines on federal use of consultants. OMB's rules state that consultants are to be used only to advise the agency on its overall management or that of a particular program the agency sponsors, not to perform work agency officials themselves should be doing or draft legislation or act as lobbyists. Consultants are to be hired only for temporary, fixed periods of time to perform clearly defined tasks. Arrangements that smack of favoritism, such as giving undue preference to former government employees, are forbidden. All consulting contracts must be approved by the agency official immediately superior to the one who hires the consultant. Federal officials, as part of this new effort, are installing two separate data-gathering systems to keep track of consultants the agencies will hire by contract and by individual appointment.

Those guidelines won't eliminate abuses of government consulting. For example, the data-gathering systems won't keep track of the literally millions of consulting contracts that cost under $10,000. Nor will the guidelines prevent an unscrupulous consultant from securing separate contracts from different agencies to do the same project. But the new rules may enable the federal government (and the public) to get some idea how much money it is spending on consultants - and what it is getting for the money. The answer, we suspect, will be that the government is spending too much for consultants and getting little in return - at which point, we do not doubt, somebody will suggest the need for a consultant to consult on what to do about the superabundance of government consultants.