Some American Airlines flight attendants have turned into hoarders.

But not the kind that keep too much stuff in their homes. This is the hoarding of "trip bids" that American Airlines management wants to put an end to as soon as possible.

Bidding for flights that FAs work is a core part of the ritual of being a flight attendant at American and every other U.S.-based airline.

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In the airline world, the more senior a flight attendant, the better that FA's chances of securing prime flights to work. Choice long-haul international flights to Europe, Asia and South America are typically the most prized flights in the American Airlines route system.

The more-senior flight attendants, some of whom have worked for the world's largest carrier for decades, are best positioned — because of their seniority — to get those flights.

But some senior flight attendants are hoarding those prime international flight assignments and selling them to junior flight attendants who otherwise might have to wait years — or decades — to fly those routes through the normal flight bidding process.

Sources said this hoarding and selling of prime trips by senior flight attendants also makes it difficult for mid-seniority flight attendants to get the same crack at those trips that they would typically get if hoarding wasn't happening.

The going price for trips being sold can vary depending on a trip's desirability, but an average price might be around $200.

American Airlines management doesn't approve of what is happening on the trip bidding front. The memo to FAs noted: "We continue to receive complaints from your colleagues that certain flight attendants are not using these systems responsibly."

Added an AA spokesman on Monday: "We take our team members' concerns seriously. So when we started receiving feedback about questionable use of bidding and trading systems by some flight attendants, we looked into it."

An AA spokesman on Monday said management believes the problem is occurring primarily among the 8,000 or so U.S. Airways legacy flight attendants who joined the ranks of AA flight attendants when the two carriers merged in 2012. The legacy U.S. Airways FAs and legacy AA FAs expect to be fully integrated into one flight attendant unit as of Oct. 1.

To help end the hoarding and selling of trips, AA is rolling out new technology to actively monitor bidding and trading systems for suspicious activity. If suspicious trading is traced to individual flight attendants, management warned, investigations could follow and lead to "suspension of individual trip trade capabilities and, in egregious cases, corrective action up to and including termination of employment."

American Airlines (NASDAQ: AAL) made clear in its memo that flight attendants who bid for a trip and get that trip then own that trip.