Keystone Aircraft Corporation was an early pioneer in airplane manufacturing. Its headquaters were in Bristol, Pennsylvania. It was formed as Ogdensburg Aeroway Corp in 1920 by Thomas Huff and Elliot Daland, but its name was quickly changed to Huff-Daland Aero Corp and then to the Huff-Daland Aero Company. The company made a name for itself in agricultural aircraft, and then in the US Army's early bomber aircraft. From 1924, James McDonnell (who would later found the McDonnell Aircraft Corporation) was the chief designer.
In 1926, Huff left the company, and it was soon purchased by Hayden, Stone & Co, who increased capital to $US 1 million and renamed it Keystone. In 1928, it merged with Loening and was known as Keystone-Loening from then until its purchase by Curtiss-Wright in 1933
The Grumman Aircraft Engineering Corporation, later Grumman Aerospace Corporation, was a leading producer of military and civilian aircraft of the 20th century.
The first Grumman aircraft was also for the Navy, the Grumman FF-1[?], a biplane with retractable landing gear[?].
In World War II, Grumman became famous for its Navy fighter aircraft, F4F Wildcat[?] and F6F Hellcat[?], and for its torpedo bomber TBF Avenger[?].