|Waco 9 of 1925 exhibited at the NASM storage facility at Silver Hill, Maryland, in June 1982|
|Role||three seat open cockpit biplane|
|National origin||United States|
|Manufacturer||Advance Aircraft Company|
|Status||about 10 survivors in 2007|
|Number built||about 270|
The Waco 9 was the first of the steel-tubed fuselage aircraft designs to be built by the Advance Aircraft Company, which became the Waco Aircraft Company circa 1929. The Model 9 was a three-seat open cockpit biplane with the ailerons on the upper wings extending outboard of the main wing surfaces. About 270 Model 9 aircraft were built during 1925 and 1926.
Operational history 
The Model 9 was of rugged construction to meet the barnstorming requirements of the period. The cost when new was between $2,025 and $2,500. A Waco 9 was flown in the 1926 Ford National Reliability Air Tour. 
The Model 9 was the first aircraft type to be fitted with aluminum floats (by the EDO Corporation in 1928). By 2007, a few examples remained airworthy in the USA and five aircraft were held by museums.
Model 9s were fitted with a variety of engines including the 90 hp (67 kW) Curtiss OX-5, the 100 hp (75 kW) Curtiss OXX-6, 100 hp (75 kW) Curtiss C-6 and the 150 hp (112 kW) Hisso A. Fitment of the various engines did not change the model number.
Military operators 
Specifications (Model 9 with Curtiss OX-5 engine) 
Data from Aerofiles
- Crew: 1
- Capacity: 2 passengers
- Length: 23 ft 4 in ( m)
- Wingspan: 29 ft 6 in ( m)
- Powerplant: 1 × Curtiss OX-5, 90 hp ( kW)
- Maximum speed: 92 mph ( km/h)
- Cruise speed: 79 mph ( km/h)
- Stall speed: 32 mph ( km/h)
- Range: 375-400 miles ( km)
- "WACO." Aerofiles. Retrieved: January 17, 20111.
- Forden, Lesley. The Ford Air Ttours: 1925-1931. New Brighton Minnesota: Aviation Foundation of America, 2003, First edition 1972. No ISBN.
- Ogden 2007, p. 607.
- Ogden, Bob. Aviation Museums and Collections of North America. Tonbridge, Kent, UK: Air-Britain (Historians) Ltd., 2007. ISBN 0-85130-385-4.