Updated from 9:06 a.m. EDT

Delta Air Lines

(DAL) - Get Report

shares dropped Wednesday after its CEO said the carrier can't survive in its current form.

Gerald Grinstein described the airline's condition as "extremely serious," and repeated management's position that a Chapter 11 bankruptcy protection filing was not out of the question.

Shares fell 19 cents, or 3.2%, to $5.76, far from its 52-week high of $16.05.

Delta recently has repeatedly warned about its financial challenges as it tries to renegotiate an existing contract with its pilots' union as part of a sweeping restructuring meant to reduce operating costs. High jet fuel prices this year have added to its financial losses and the company's stock has slumped. The company recently announced a reconfigured senior management team after a series of high-profile departures.

Grinstein made the remarks at a transportation industry conference in New York, where he said Delta's access to capital markets has "virtually disappeared."