In May of 1963 Beechcraft began test flights of the first King Air. On September 9, 1964 the first production Model 90 rolled off the line. By the end of 1968 more than 400 had been delivered with the original Pratt and Whitney PT-6A turboprop engines, rated at 500 shaft horsepower (shp).

Trivia:

During the administration of President Lyndon Johnson, the United States Air Force acquired a B90 to transport Johnson between Bergstrom Air Force Base (near Austin, Texas) and the Johnson family ranch near Johnson City, Texas. When Johnson was aboard, the aircraft used the callsign Air Force One. The military designation of the B90 used for executive transport was VC-6A. This aircraft is now on display, with other presidential aircraft, at the National Museum of the United States Air Force at Wright Patterson Air Force Base near Dayton, Ohio.

Referenced from Wikipedia

Performance Data

Horsepower: 550

Top Speed: 250 kts

Cruise Speed: 245 kts

Stall Speed (dirty): 77 kts

Takeoff

Ground Roll: 1553 ft

Over 50 ft obstacle: 2024 ft

Rate Of Climb: 1870 fpm

Ceiling: 27620 ft

Gross Weight: 10100 lbs

Empty Weight: 5996 lbs

Fuel Capacity: 474 gal

Range: 1290 nm

Landing

Ground Roll 1030 ft

Over 50 ft obstacle: 2110 ft

Rate of Climb (One Engine): 470 fpm

Ceiling (One Engine): 14390 ft

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