U.S. Air Service




Avro 504K

Development and Operation

The A.V. Roe Company's design designated as the 504 was typical for its time frame consisting of a wire-braced wooden box girder. Upper longerons were straight in side-elevation. The fuselage was terminated in a vertical sternpost to which was attached a coma-shaped rudder. There was no vertical fin and the tailskid was attached directly to the bottom of the rudder. The 2-bay wings were of equal span. Construction of the 504 design began is April 1913 and the first flight tests were conducted at Brooklands in July 1913.

The aircraft underwent numerous variations, most of which dealt with the type of engine was to be installed. Eventually, the 504K configuration arose. Under this designation adapters were installed by which any of the engine types could be fitted into the 504 airframe. All engines were carried on an overhung mounting and had an open-faced cowling. After a rather undistinguished military career it was realized that the Avro 504K could be used, because of its flying characteristics, was well suited for use as a trainer aircraft. The Avro 504K was such a delight to fly that it laid the foundation for the development in England for logical flying instruction (i.e. the Gosport System). In its mode as a trainer the aircraft was used as the next step, beyond the `Rumpty' in the progression of the student toward flying combat aircraft.

American cadets undergoing flight instruction in England progressed from the `Rumpty' to the Avro 504K before beginning familiarization flights with the aircraft they would be assigned in front-line service.


Aircraft and Flight Characteristics




Fuel and oil



1231 lbs.

360 lbs.

238 lbs.

1829 lbs.

Engine Options

100 hp Gnône Monosaupape,
110 hp Le Rhône,
130 hp Clerget, et.al.


Max. Speed at Ground Level

Max. Speed at 8000 ft.

Max. Speed at 10,000 ft.


95 mph

87 mph

85 mph


8000 ft.

10,000 ft.


10 minutes

16 minutes


16,000 ft.


3 hrs.


36 ft.


29 ft. 5 inches


10 ft. 5 inches


1. British Aeroplanes, 1914-1918
by J.M. Bruce

2. Photo from the Norwegian Air Museum website

To find other features on the DOUGHBOY CENTER visit our
General Headquarters

For further information on the events of 1914-1918
visit the homepage of
The Great War Society

Additions and comments on these pages may be directed to:
Michael E. Hanlon (medwardh@hotmail.com) regarding content,
or to Mike Iavarone (mikei@mcs.com) regarding form and function.
Original artwork & copy; © 1998, The Great War Society