Less passangers, higher fuel cost = 3 airlines bankrupcy.

CNN) -- Skybus Airlines announced Friday it is shutting down its passenger flights -- becoming the third airline this week to cease operations.

The low-cost carrier couldn't overcome "the combination of rising jet fuel costs and a slowing economic environment," the company said Friday. "These two issues proved to be insurmountable for a new carrier."

Skybus, an Ohio-based airline founded in 2004, will cease operations effective Saturday.

Earlier in the week, ATA Airlines and Aloha Airlines announced they would shut down flights as both companies work through bankruptcy filings.

ATA, an Indiana-based low-cost charter airline, filed for Chapter 11 status Wednesday as a result of financial problems "following the loss of a key contract for our military charter business," the company said. The company started operation in 1973.

Hawaii-based Aloha Airlines announced Sunday it would shut down its passenger operations this week after filing for bankruptcy protections last month, concluding 61 years of service.

In its bankruptcy filing, Aloha said it was unable to generate enough revenue from its inter-island passenger flights because of below-cost fares by competitors Mesa Air Group's go! airline. The company said it was forced to match the competitor's fares during an unprecedented increase in the cost of jet fuel.

Skybus said all flights Friday would be completed; passengers with reservations for Saturday and beyond were told to seek refunds from their credit card companies.