The first variable-pitch propeller developed in the United States was invented by Seth Hart and Robert I. Eustis of Los Angeles, California, and demonstrated in 1917. Possibly the second variable-pitch propeller in the United States, this 1920 controllable and reversible propeller is the product of the first government sponsored variable-pitch propeller development program. It was completed following a two year development at the Engineering Division, McCook Field, Dayton, Ohio, and is an improved version of a design submitted to the Army for evaluation in 1918 by Hart and Eustis. This propeller had a faulty blade retention system, and was unable to keep wooden or Micarta blades connected to the hub.

Display Status

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.

Object Details

Date

1920

Country of Origin

United States of America

Type

PROPULSION-Propellers & Impellers

Designer

Seth Hart

Physical Description

Type: Two-Blade, Variable-Pitch, Wood and Metal
Engine Application: 112 kw (150 horsepower) Hispano Suiza engine

Dimensions

3-D (Propeller): 269.2 × 30.5 × 27.9cm, 48.5kg (8 ft. 10 in. × 1 ft. × 11 in., 107lb.)
Storage (Aluminum Pallet): 314.3 × 121.9 × 124.5cm, 284kg (10 ft. 3 3/4 in. × 4 ft. × 4 ft. 1 in., 626lb.)

Materials

Overall: Doped fabric, Paint, Laminated wood, Steel, Brass, Solder, Aluminum alloy
Hub: Steel
Blades: Fabric-covered Birch

Inventory Number

A19340025000

Credit Line

Gift of United States War Department, Air Corps Material Division

Data Source

National Air and Space Museum

Restrictions & Rights

Usage conditions apply
For more information, visit the Smithsonians Terms of Use.