(CNN) -- Despite calls from President Obama to beef up the program designed to provide security aboard U.S. flights, the Federal Air Marshal Service is in disarray, a CNN investigation has found.

In more than a dozen interviews across the country, air marshals said the agency is rife with cronyism; age, gender and racial discrimination; and attempts by managers to make the agency appear more efficient than it is by padding numbers.

Air marshals describe an agency in chaos, where bored and frustrated marshals focus more on internal squabbles than watching for bad guys.

The marshals refused to let their identities be known, for fear of retaliation in an agency that is driven, they say, by intimidation and favoritism.

After a Nigerian's attempt to blow up an airliner preparing to land in Detroit, Michigan, on Christmas Day, a growing number of critics have called for either the elimination or a total overhaul of the agency.

Last week, President Obama asked Congress for an additional $85 million to boost the air marshals program, known by its acronym FAMS, after the foiled attack aboard the jet coming from the Netherlands.

U.S. officials have charged Nigerian Umar Farouk AbdulMutallab with attempting to blow up the airliner. He was subdued by passengers and crew.

No air marshals were on the flight, generating additional criticism of the service.

Despite efforts by Obama and assurances by Homeland Security Secretary Janet Napolitano that FAMS will become more effective, one air marshal told CNN, "Nothing's particularly changed for me since Christmas Day, or (for) a big percentage of people that I work with. Everything is pretty much the same."

In January, Napolitano testified before a Senate committee, where she vowed, "We will strengthen the capacity of aviation law enforcement, including the Federal Air Marshal Service."

International flights are considered to have the highest risk.

However, air marshals from a half dozen FAMS field offices said the agency continues to assign marshals to short, regional routes on small jets. The marshals told CNN that lots of short-haul flights make the agency look more productive on paper.

The marshals said if someone dares criticize a manager, he or she can be banished to what they call "Team America," referring to the regional trips.

Managers and favored employees receive the perk of traveling international routes, they said.

Repeatedly, air marshals reported that the decision on who flies on what flights are driven by extra pay for managers, and office politics -- not security.

Despite repeated requests, FAMS and its parent agency, the Transportation Security Administration, declined to give CNN an interview.

However, TSA spokesman Nelson Minerly provided a statement, saying, "The Transportation Security Administration's Federal Air Marshals are strategically deployed aboard U.S. flagged air carriers to ensure the safety and security of the traveling public.

"The Federal Air Marshal Service is currently training and deploying fellow federal law enforcement officers to support the administration's enhancement in aviation security. Federal Air Marshals and these additional highly trained officers are being deployed aboard an increasing number of flights worldwide to keep air travel safe," Minerly wrote.

Rep. John Duncan, R-Tennessee, is one of FAMS' harshest critics.

"It's just a total waste of money," he told CNN in a recent interview.

"I know that any time you create a federal bureaucracy, it just grows and grows, and the appropriation just goes up and up, but ... look at the record. They haven't done anything."

"I had the statistic from last year," the Republican said. "They made four arrests for an appropriation of $800 million. It came out to more than $200 million per arrest. It's just ridiculous."

Rep. Sheila Jackson Lee, D-Texas, doesn't want FAMS eliminated, she wants it revamped.

"If we've got those kinds of problems, we need to get a ready broom and sweep," she said. "The only way we are going to ensure the security and safety of the American people is that we have staff par excellence, and I know they are out there."

Although the actual number of air marshals is classified, it has been widely reported that the number of air marshals covering 28,000 flights per day is fewer than 4,000. Even with a generous calculation, the marshals only cover 5 percent of flights, according to CNN assessments.

CNN has been studying FAMS for three years, and during that time, air marshals have accused managers of using creative accounting to pad the numbers given to Congress.

They describe an agency in chaos that, in some cases, promotes discrimination against minorities.

"We don't have managers who provide training or provide leadership or do anything other than produce conflict," one said.

John Mueller, a political science professor at Ohio State University, has completed a cost-benefit analysis of U.S. aviation security. He concluded many measures such as FAMS are little more than a waste of taxpayer dollars.

"We have seen with the underwear bomber (AbdulMutallab), the passengers aren't going to sit around waiting for someone else to do something. Because their lives are at stake, they are going to jump in. So essentially from a hijackers' standpoint, this idea of replicating 9/11 is close to impossible as far as I can see," Mueller said.

The air marshal program was set up in 1970, after a rash of airline hijackings, and it was expanded significantly after the terrorist attacks of September 11, 2001. Specially trained to safeguard passengers and crew aboard crowded aircraft, air marshals were seen as a critical component in the overall effort to secure America's commercial aviation system.



CNN's Deb Krajnak contributed to this report.