A bird flies by in the foreground as a Southwest Airlines jet comes in for a landing at McCarran International Airport on May 25, 2020 in Las Vegas, Nevada.Ethan Miller | Getty ImagesMore than 400 Southwest Airlines mechanics and technicians, about 15% of the work group, have received notices warning them about potential furloughs, the carrier said Wednesday.Southwest has asked employees to take 10% pay cuts to avoid furloughs, which would be the first in the Dallas airline’s nearly 50 years of flying. Southwest warned 42 material specialists about possible furlough earlier this month.U.S. airlines have furloughed more than 30,000 workers as they struggle from weak demand in the coronavirus pandemic — a crisis executives say is the worst in their history. Including buyouts and other voluntary departures, the industry will shed the equivalent of some 90,000 employees by the end of 2020, according to Airlines for America, a trade group that represents most U.S. carriers.The carrier said it has sent 403 mechanics and technicians federally mandated notices warning them that their jobs are at risk. The involuntary cuts could take effect as early as Jan. 25.”We are not closing the door to further discussions, but we need agreements to be reached to help us save these employees’ jobs and address the extremely challenging economic conditions we face,” said Russell McCrady, vice president of labor relations at Southwest.The union didn’t immediately comment but AMFA plans to continue talks with the company, according to a memo to members, which was seen by CNBC.Negotiations are ongoing with Southwest Airlines pilots and flight attendants, but unions for both groups have bristled over a force majeure clause the company proposed, which the labor groups say threatens job security.