Allegiant Air fined $318,000 for keeping plane cabins too hot during tarmac delays

Discounter Allegiant Air has been fined $US225,000 ($A318,000) by the US Department of Transportation for making passengers sweat during tarmac delays in 2016 and 2017.

Regulators found that the Las Vegas-based airline "failed to provide passengers a comfortable cabin temperature" on 10 flights delayed on the tarmac at four airports.

The airports: Las Vegas; Albuquerque; El Paso, Texas; and Dayton, Ohio. Seven of the 10 flights were in Las Vegas, where temperatures routinely stay above 100 degrees fahrenheit (37 degrees Celcius) throughout the summer.

In one case, the DOT said, Allegiant also did not provide food and water to passengers during the tarmac delay or let them know they could deplane, as required by DOT rules.

The government said it based its findings on passenger complaints, crewmember statements, temperature readings, reported medical incidents, operational considerations such as the use of external cooling units or air carts during the delays, and decisions to deplane passengers.

Allegiant told investigators the affected flights were subjected to outdoor temperatures generally in the triple-digit range and in some cases exceeding 110 degrees. It said the outdoor temperatures made cabin cooling during the tarmac delays "difficult at best" despite Allegiant's use of air conditioning carts, ground power units, and other measures to supplement internally-generated cooling.

The airline said it made what it believed to be "sensible decisions" given that situation and "passengers' consistent strong desire to get to their destination as quickly as possible."

Allegiant also said it is revising its training and procedures to better effectively address cabin temperature and aircraft beverage provisioning issues. The airline said its transition to an all Airbus fleet, which will be completed by the end of the year, should also help as its older MD-80 aircraft were the most prone to cabin temperature issues.

The airline must pay the fine within 30 days. This is Allegiant's second fine this year. In April, the DOT fined Allegiant $US250,000 for violating the department's airline consumer protections rules. The DOT said the airline "failed to provide passengers with disabilities adequate and timely assistance in moving within airport terminals, and did not adequately respond to complaints filed by passengers with disabilities. In addition, Allegiant failed to provide timely responses to consumer complaints and failed to make prompt refunds to consumers when they were due."

TNS