In 1952 the airline moved their headquarters from Wisconsin to Minneapolis, Minnesota, and that December their name became North Central Airlines. Soon the airline ran into financial trouble when President Francis Higgins left, making Hal Carr the president. Carr quickly got the company out of debt and made it more reliable. Over time the company expanded their fleet to 32 DC-3s.
A growing airline
Revenue passenger traffic, in millions of passenger-miles (scheduled flights only)
In October 1952 Wisconsin Central scheduled flights to 28 airports, all west of Lake Michigan, from Chicago to Fargo and Grand Forks. It added Detroit in 1953, Omaha and the Dakotas in 1959, Denver in 1969 and a nonstop Milwaukee to New York LaGuardia in 1970. It added five Convair 340s from Continental Airlines to its fleet of DC-3s, the first entering service in 1959. In 1960 North Central hit the one million passenger mark; in May 1968 they flew to 64 airports, including two in Canada.
The Civil Aeronautics Board (CAB) classified North Central as a "local service carrier," flying to cities within one region and feeding passengers to larger "trunk airlines" that flew nationwide. North Central eventually was allowed a few routes outside the Midwest: to Washington, D.C.-National, New York-LaGuardia, Boston, Denver, and Tucson.
Republic retained "Herman the duck" and North Central's colors
Republic kept North Central's hubs at Minneapolis and Detroit, and Southern's hub at Memphis. Within a few years they closed Hughes' former hub at Sky Harbor at Phoenix; reduced North Central's sizeable station at O'Hare at Chicago; and reduced Southern's sizeable station at Hartsfield at Atlanta. Republic also quickly downsized North Central's operations to and among smaller airports in the upper Midwest, concentrating their fleet at the Minneapolis and Detroit hubs.
August 4, 1968 – North Central Airlines Flight 261, a Convair CV-580, collided with a Cessna 150 11.5 miles (19 km) miles southwest of Mitchell Airport in Milwaukee at 2,700 feet (820 m), as the northbound Convair from Chicago descended for an approach to runway 7. The cabin section of the northwest-bound Cessna embedded in the Convair's forward baggage compartment. The Convair lost electrical power and the right engine was shut down due to a damaged propeller, but the captain completed a successful emergency landing six minutes later. All three teenagers aboard the Cessna were killed and the first officer on the Convair had serious leg and head injuries, but the other 3 crew and 8 passengers were uninjured. Heavy accumulation of insect debris on the windshield was cited as a contributing factor.
December 20, 1972 – Flight 575, a DC-9-31, was cleared by an air traffic controller for takeoff at O'Hare in Chicago, while recently arrived Delta Air Lines Flight 954, a Convair CV-880, was instructed to taxi across the runway to a holding area. The DC-9 had just started to climb in the heavy fog when it clipped the tail of the CV-880. Ten of the 45 people on board the North Central DC-9 were killed in the resulting collision and crash and 15 were injured; there were two minor injuries on the Delta CV-880.
July 25, 1978 – Flight 801 departed Kalamazoo-Battle Creek International Airport in Kalamazoo, Michigan at 7:00 am EDT in fog. The Convair 580 struck a bird immediately after takeoff frum runway 17 and lost power in its left engine. It flew an additional 79 seconds, banking left, then crash-landed into a cornfield east of the airport. Of the 40 passengers and three crew on board, 2 passengers and a crewman had serious injuries, but there were no fatalities. (photo) The NTSB report attributed the cause of the crash to the captain's failure to follow proper emergency procedures.
^World Airline Directory. Flight International. March 20, 1975."482.