In an open letter to their passengers, the pilots of Nevada-based budget carrier Allegiant Air have gone public with their concerns about what they see as sagging service and safety standards for the airlines.

“[W]e are uncomfortable remaining silent about company practices that negatively impact our customers’ travel and vacation, including your comfort, and – most importantly – your safety,” begins a letter posted on the website for the union representing Allegiant pilots.

The letter points out that Allegiant is the “most profitable airline in the industry and has had 48 consecutive profitable quarters,” while at the same time experiencing a record number of delays and cancellations, resulting in “the second-highest customer complaint rate out of any U.S. commercial airline.”

According to the union, management is “content with just barely meeting acceptable safety standards,” and is “driving a race to the bottom in service, safety standards and treatment for veteran pilots.”

The pilots claim that there are “persistent mechanical problems due to poor equipment and the company’s unwillingness to invest in its operation or its workforce,” and accuses CEO Maurice Gallagher of making millions of dollars while allegedly refusing to invest company money in infrastructure and employees.

“The company’s profits are propped up by the extra workload placed on its understaffed, underpaid and overworked workforce and its minimalist approach to maintenance and safety,” reads the letter. “Allegiant represents the worst in an economy today where greedy CEOs disregard needed investments into a company’s workforce and infrastructure at the expense of passenger safety and for the benefit of Wall Street.”

The union, speaking to Skift.com, points to a recent report [PDF] from the Teamsters Aviation Mechanics Coalition (TAMC) that notes several “air returns and diversions related to maintenance-related issues” involving Allegiant’s fleet during Sept. and Oct. 2014.

“The lack of experience, parts, tooling and training combined with the age of the fleet; roughly 22.2 years, is creating a dangerous paradigm that could eventually lead an accident resulting in serious injury and loss of life,” concludes the TAMC report. “In conversations with some of the pilots it became evident that they are used to flying these aircraft with what they consider ‘nuisance’ issues. A situation such as this creates a ‘Bad Norm’ where a perceived ‘nuisance’ is in actuality the precursor to an accident.”

The airline and the Teamsters have been at odds for a few years now over issues of benefits and rules involving pilot seniority and scheduling. The union recently voted overwhelmingly in favor of approving a strike.

“This is not something we prefer to do,” the president of the union, which also represents pilots of 10 other airlines, told the Las Vegas Review-Journal. “We believe in a progressive approach (to labor negotiations), but this is a sign of how bad it’s gotten and how concerned we are.”

The airline’s Chief Operating Officer defended Allegiant’s record to Skift.com.

“Allegiant has one of the best safety records among passenger airlines in the world, and complies with all FAA regulations,” reads the statement from the COO, who adds that the airline is committed to negotiating a contract with our pilots that is “in the best interest of our pilots, as well as our other work groups and the health of our business.”

The executive accuses the union of engaging in “scare tactics, including manipulating facts in an attempt to manipulate our customers,” and says such actions are “irresponsible and unfair to our customers.”

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