File D 52.1/Fokker/55 McCOOK FIELD REPORT, SERIAL No. 1669
Air Service Information Circular
(Aviation)
PUBLISHED BY THE CHIEF OF AIR SERVICE, WASHINGTON D.C.

Vol. III October 1, 1921 No.288

OFFICIAL PERFORMANCE TEST OF FOKKER
MONOPLANE D-VIII EQUIPED WITH
110 H.P. OBERURSEL ENGINE

(FLIGHT TEST BRANCH PERFORMANCE TEST REPORT NO. 63)

Prepared by Engineering Division, Air Service
McCook Field, Dayton, Ohio
May 20, 1921

WASHINGTON
GOVERNMENT PRINTING OFFICE
1921

OFFICIAL PERFORMANCE TEST OF FOKKER MONOPLANE
D-VIII EQUIPPED WITH 110 H.P. OBERURSEL ENGINE.

OFFICIAL PERFORMANCE TEST-SUMMARY OF RESULTS
May 20, 1921
Airplane: Fokker Monoplane
No.: P-165.
Type: D-VIII.
Engine: 110 H.P. Oberursel.
Propeller: Axial 01476.
Equiped as: Alert type.
Weight empty (including water): 848 pounds.
Armament and equipment: 74 pounds.
Crew: 180 pounds.
Gasoline: 113 pounds.
Oil: 23 pounds.
Weight loaded: 1,238 pounds.
Weight per square foot: 11.45 (108 square feet)
Weight per horsepower: 9 (137 H.P. at 1,390 R.P.M.).

Endurance, full throttle at 10,000 feet (including climb): ------
Minimum speed at sea level (lowest throttle): 59 M.P.H.
Landing Speed: 55 M.P.H.

PILOTS OBSERVATIONS

The airplane has a tendency to turn to the right in taxying, takes off very quickly, climbs very rapidly, and is very maneuverable.
It is very easy to fly, and the controls are sensitive. It is tail heavy, but so light on the controls that it is not tiresome to fly.
The visibility is very good.
The machine guns are placed that in the event of a crash, the pilot would undoubtedly be injured by being thrown against the same.
The airplane lands very slowly with a slight tendency to drop the right wing, and to turn to the right on the ground.
The controls for the engine are very inconveniently located, inasmuch as the throttle for the gas is on the left of the fuselage, and the throttle for the air is on the left side of the control stick.

LEIGH WADE,
First Lieutenant, Air Service, Test Pilot.

DESCRIPTION OF AIRPLANE.

DIMENSIONS.

Over-all span: 27 feet 7 inches.
Over-all length: 19 feet 4 inches.
Over-all height: 8 feet 6 inches.
At rest: 5 feet 8 1/2 inches.

AIRPLANES.

Wing Curve: Fokker varying.
Sweepback: 3 3/4 inches.
Total area, including ailerons: 108 square feet.

UPPER PLANE.
(INCLUDING CENTER SECTION.)

Span: 27 feet 7 inches.
Chord: 4 feet 11 inches
Area with ailerons: 108 square feet.

LOWER PLANE.

None.

AILERONS OR FLAPS.

Number: 2.
Arrangement: On trailing edge of wing.
Upper length: 5 feet 2 1/8 inches.
Upper chord: 10 3/8 inches.
Distance from center of ailerons to longitudinal axis of airplane: 10 feet 3 1/2 inches.

CENTER SECTION.

None.

STABILIZER.

Setting: 3.5 deg positive.

FUSELAGE.

Maximum cross section shape: Round.
Maximum cross section dimension: 3 feet 6 1/2 inches.

LANDING GEAR.

Number of wheels: 2.
Tread: 5 feet 9 5/8 inches.
Shock-absorbing system: Rubber chord.
Braking device: Tail skid.

DISTRIBUTION OF WEIGHTS.
(By pounds.)

Weight, empty (with water): 848.
Armament and equipment: 74.
Crew: 180.
Gasoline: 113.
Oil: 23.
Weight, loaded: 1,238.
Weight on front wheels (tail skid on ground): 1,032.
Weight on tail skid (tail skid on ground): 206.
Weight on front wheels (flying position): 1,126.
Weight on tail skid (flying position): 112.
Center of gravity (distance from wheels in flying position): ------
Provisions for special equipment not carried during test.

DESCRIPTION OF POWER PLANT.

ENGINE.

Make: Oberursel.
Factory No.: 3332.
A.S. No.: ------
Type: 9-cyl. rotary.
Number in plane: 1.
Location: Nose of fuselage.
Rated H.P.: 110 H.P.
Rated R.P.M.: 1,390.
Bore: 112 m/m or 4.41".
Stroke: 170 m/m; 6.693"
Compression ratio: 4.7:1
Weight, dry: 331 pounds
Weight of water in engine: None.

IGNITION.

Battery or magneto: Magneto
Make: Bosch
Number: 1.
Advance, degrees: 22 deg.
Gas interrupter: ------
Plugs, make: Bosch 17 D-V.
Type: Metal body, porcelain insulator.
Gap: 0.020.

CARBURETORS.

Make: Rene Tampier
Type: Bloc tube.
Number: 1.
Setting jet: ------
Mixture control: Manual operated.

RADIATORS.

None.
Water capacity of whole system: No water used.

EXHAUST PIPES.

Description: No exhaust pipes used, gases exit through exhaust valve.

LUBRICATION.

Capacity oil tank: ------
Dimensions oil tank: ------
Oil used (brand): Castor.
Oil pressure: 2 lbs per sq. in.
Type pump: 4-cylinder plunger Gnome type.
Description lubrication system: Oil enters pump, is forced through tube in hollow crank shaft to rear main bearing, remainder of oil to wrist pins, the line through crank shaft is carried on forward and oils front main bearings.

FUEL SYSTEM.

Number of tanks: 1
Location: Fuselage, just rear of engine.

ENGINE CONTROL.

Description: Rod and lever.

PROPELLER.

Make: Edulzug Axial
Number of blades: 2.
Diameter: 260 m/m or 10.21'.
Tips: Not tipped.
Manufacturer's No.: 16065.
Remarks: 16065 110 P.S. LeRhone D 260, St 260 TO

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