
Specifications
Year: 1917
Status: Retired, Out-of-Service
Manufacturer(s): Societe Pour l'Avions et ses Derives (SPAD) - France
Production: 1,000
Capabilities: Fighter; Reconnaissance (RECCE);
Status: Retired, Out-of-Service
Manufacturer(s): Societe Pour l'Avions et ses Derives (SPAD) - France
Production: 1,000
Capabilities: Fighter; Reconnaissance (RECCE);
Crew: 2
Length: 25.72 ft (7.84 m)
Width: 36.78 ft (11.21 m)
Height: 9.19 ft (2.8 m)
Weight (Empty): 1,499 lb (680 kg)
Weight (MTOW): 2,293 lb (1,040 kg)
Length: 25.72 ft (7.84 m)
Width: 36.78 ft (11.21 m)
Height: 9.19 ft (2.8 m)
Weight (Empty): 1,499 lb (680 kg)
Weight (MTOW): 2,293 lb (1,040 kg)
Power: 1 x Hispano-Suiza 8Bc V-8 water-cooled engine developing 220 horsepower.
Speed: 112 mph (180 kph; 97 kts)
Ceiling: 22,966 feet (7,000 m; 4.35 miles)
Range: 249 miles (400 km; 216 nm)
Rate-of-Climb: 788 ft/min (240 m/min)
Ceiling: 22,966 feet (7,000 m; 4.35 miles)
Range: 249 miles (400 km; 216 nm)
Rate-of-Climb: 788 ft/min (240 m/min)
Operators: Belgium; France; Kingdom of Italy; Imperial Japan; Imperial Russia; Soviet Union; United States; Uruguay
To fulfill the French air Service (Aeronautique Militaire) requirements, Bechereau attempted to continue using the proven qualities of his previous single-seat biplane fighter offerings. A longer fuselage was necessary when incorporating a second observer's/gunner's cockpit aft of the pilot. Sections of the wings were cut out for improved viewing while many other qualities of the design remained consistent with the period - the front-mounted engine driving a two-bladed wooden propeller, parallel struts and cabling to stiffen and control the "over-under" wing structure and conventional single-finned tail unit. The undercarriage was wheeled though fixed through reinforced struts and the tail supported by a simple skid. The pilot was given a single fixed, forward-firing 7.7mm Vickers series machine gun and the observer could manage an optional 7.7mm Lewis machine gun on a trainable mounting. The aircraft emerged under the company model number of "SPAD 11", also written as SPAD S.XI.
Power to the S.XI was served through 1 x Hispano-Suiza 8Bc series V-8 water-cooled engine of 200 horsepower and this allowed a maximum speed was 112 miles per hour with an mission endurance time of approximately 2.25 hours. The aircraft's service ceiling was listed at 23,000 feet with a rate-of-climb of 9,850 feet reached in roughly 12.5 minutes. Some airframes were also fitted with a Renault 12-cylinder engine instead of the aforementioned Hispano-Suiza installation, though this powerplant actually reduced performance figures and was not popular.
The SPAD S.XI joined the war during 1917 and eventually proved itself not a success. The modified single-seat fighter approach for a larger two-seat design made the airframe tricky in its handling while performance from the engine of choice proved underwhelming. The type did hold characteristics that superseded some existing types then in service with French forces so the aircraft still managed to serve in notable numbers. It managed a frontline status until the fall of 1918 before being replaced by the SPAD S.XVI - itself a direct offshoot of the S.XI though outfitted with a Lorraine-Dietrich engine of 250 horsepower. These proved no better than the originals but were kept in action nonetheless.
Operators beyond the French Air Service became Belgium, Italy, Japan, Russia (into the Soviet Union years), Uruguay and the United States (American Expeditionary Force - "AEF").
Armament
1 x 7.7mm Vickers fixed, forward-firing machine gun
1 OR 2 x 7.7mm Lewis machine gun on trainable mount in rear cockpit.

Variants / Models
• S.XI - Base Series Designation
• S.XI A2 - Formal production model designation