The Aircraft Owners and Pilots Association is considering filing a lawsuit against New York to block legislation signed by Governor Pataki that would require flight training schools to force its student applicants to undergo background checks before they start instruction.

The Maryland-based association, which had lobbied aggressively against the legislation, is claiming that the state lacks jurisdiction over aviation security requirements for student pilots. It also is warning that the checks would drive away business from New York flight schools by making it more difficult and time-consuming for aspiring pilots to enter into training. “If New York is putting restrictions on flight training, people will just go to other states,” the general counsel of the pilots association, John Yodice, told The New York Sun.

Mr. Pataki signed the bill into law late last week, saying in a statement that such precautions are necessary to provide the state with “vital information that can help prevent people harboring bad intentions from gaining access to this critical knowledge.”

The Assembly first passed the bill in 2002, but Mr. Pataki signed it for the first time just days before the fifth anniversary of the September 11, 2001, terrorist attacks. Sponsored by Assemblyman Joseph Morelle, the bill passed the Senate unanimously and the Assembly 142 to 1 in June.

Under the New York law, student applicants at flight schools now have to provide any criminal history information to the Division of Criminal Justice Services, which will determine if applicants are cleared for instruction. Applicants in New York cannot begin training until they get clearance from the federal government.

When the law takes effect in two months, New York will be the only state to require student pilot background checks. In 2002, Michigan passed a similar law, which was contested in federal court by the association. The lawsuit was dropped after Governor Granholm repealed the law in 2003.

“We will pursue every possible venue to get this law overturned,” the executive vice president of government affairs for the association, Andy Cebula, said in a statement. “We succeeded in changing a similar law in Michigan, and we are committed to fight this in New York.”

In flight schools across the country, background checks are handled by the Transportation Security Administration, which is part of the Department of Homeland Security. The federal government tightened security measures in response to the terrorist attacks, which were carried out by terrorists who received flight training at American schools.

The government does not require criminal background checks for flight students, but requires that foreigners who wish to attend flight schools submit fingerprints and passport and visa information to the Transportation Security Administration.

At issue is whether federal security aviation laws are pervasive enough to preempt state laws like the one passed by Mr. Pataki. The legal question will likely revolve around the “Supremacy Clause” in the Constitution, which says, “This Constitution, and the laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the authority of the United States, shall be Supreme Law of the land.”

Because the federal government has not expressly forbidden states from passing laws regulating aviation security background checks at flight schools, a federal court deciding on the matter would determine if federal laws on aviation security requirements are comprehensive enough to override a state law.

A spokeswoman for the Transportation Security Administration said the agency would not sue the state to overturn the law. The agency, however, has taken a position that state laws regulating security assessments of flight school applicants are preempted by federal law.

“The comprehensive nature of Federal regulation of aviation safety and security evinces a clear intention by the Congress to occupy the field in the aviation sector to the exclusion of state law,” the chief counsel of agency, Francine Kerner, wrote in a letter to the association dated August 8. The association had requested the agency’s opinion on the matter.

Officials at the pilot association argue that criminal background checks, whether they are imposed at the state level or by the federal government, would do little to winnow out dangerous applicants.

The association has put in place an “Airport Watch” program that “uses the more than 650,000 pilots as eyes and ears for observing and reporting suspicious activity,” according to its Web site.