United Airlines have sent their staff a memo saying they're not afraid to sack flight attendants who are attempting to manipulate the internal workings of the airline for their own gain.
The warning was issued after an investigation was launched into a rogue group of flight attendants the company suspects of making bids for cushier and better paying flying routes in exchange for kickbacks, using coded speech like "hugs", "kisses" and "candy canes".
The most desirable routes for flight attendants are generally long-haul flights, and standard practice with most US airlines is for crews to bid for these routes, with senior staff rewarded the best trips.
United Airlines has reported a growing problem of flight attendants pairing up and trading to sell, and talking in coded language to communicate and conspire without detection.
While United allows attendants to trade routes with fellow attendants for "unforeseen events", parking of trips with the intent to sell them on is expressly prohibited, and has been criticised by the airline and the Association of Flight Attendants (AFA), a union organisation.
"What we're addressing is the growing problem of selecting, trading, or parking a pairing to broker, buy, or sell it to another flight attendant," P. Douglas McKeen, senior vice president for labour relations at United Airlines, wrote in a memo.
"When we discover that it's occurring, we will fully investigate and take appropriate action, up to and including discharge.
"This is about fairness, plain and simple. No flight attendant should have an unfair advantage beyond their seniority rights when it comes to managing their schedule or accessing flying opportunities."
The airline said in their investigation they searched social media sites and found the flight attendants were using secret code words as part of the scam. They promised one another "candy canes", "hugs", "kisses" and "expressions of appreciation".
The AFA called the behaviour "egregious" and said many members had voiced concern but had not complained to management "because we are unionists".
"It is disappointing to learn that those involved in this activity have elected to put their personal gain ahead of the well being of our greater collective," the AFA said in a statement.
"We know schedules are very important to our flight attendants, and we work closely with AFA to make sure our flight attendant scheduling is fair for all of them," a United spokesman told Skift.
The investigation by United into the alleged scheme is ongoing.
It's the second time this month the airline has been forced to tackle staff abuse of its employee perk system.
United Airlines sacked 35 employees allegedly involved in a "broking scheme", where travel passes, a company perk, were found being sold on to the public for individual profit.
The airline's investigation into the abuse of the perks program began when nine passengers travelling overseas were unable to name the employees who sold them their tickets, according to The Chicago Tribune.
The passengers had bought tickets which gave them year-long travel for between $5150 to $5885 ($US3500 to $US4000) per person.
The United employees scammed the sale by telling the airline the tickets were going to friends or family members.