Altimeter in Display Case, Aviation Section US Signal Corps, 15,000FT, WWI OH-6 Cayuse it has a manufacturing date

it has a manufacturing date of Feb 14

As the engine speed increased

and a taller tail fin

but the center knob is provided with which to rotate the dial

Altimeter in Display Case, Aviation Section US Signal Corps, 15,000FT, WWI OH-6 Cayuse it has a manufacturing dateThis is an Altimeter used in military aircraft of the Aviation Section, US Signal Corps, which existed from 1914 1918 and was the WWI era precursor to today's US Air Force. This altimeter crudely measured altitude from 0 15,000 ft. By loosening the small retaining lever, gripping the knurled rim of the faceplate and turning, the numerical scale rotates clockwise or counter clockwise while the pointer remains stationary, to correct the altitude reading