Fokker D.XXI Timeline
14 November 1934: The D.XXI design is placed before the Netherlands Army Air Division. It was
designed by Ir. Schatzki and his team in close liaison with Rolls-Royce Ltd. to meet the
requirements of a specification drawn up by the Royal Netherlands Indies Army.
Early 1935: The Army Air Division (Luchtvaortafdeling - LVA) Signed a contract for one prototype.
27 March 1936: 1st flight of D.XXI, FD-322 prototype at Welschap airfield near Eindhoven piloted by Fokker's
Czech chief test pilot, Emil Meinecke.
Engine: Bristol Mercury VI-S: 645 hp.
Armament: 2 x 7.62 mm. M.36 FN Browning machine guns in the fuselage/500 rpg. + 2 x 7.62 mm. M.36
machine guns in the wings./300 rpg.
Note: The D.XXI was a sturdy monoplane of simple construction, easily flown and possessing no serious vices.
12 November 1936: DF-322 was delivered to Soesterberg for test trials against the Koolhoven Fk-58.
Note: The first flight of the Koolhaven Fk.58 was not until September 1938.
During 1937: The Netherlands Government voted to expand the LVA. 36 D.XXIs powered by the Bristol
Mercury VII or VIII (830 hp.) were ordered.
During 1937: Finland's government ordered 7 D.XXIs and acquired a manufacturing license. Production
began at the Valtion Lentokonetehdas (State Manufacturing Factory).
20 July 1938: 1st flight of LVA (Netherlands) production D.XXI No.212. The following information comes
from " War Planes of the Second World War, Fighters Vol.3 by William Green.
Engine: Bristol Mercury VIII: 830 hp.
Loaded Weight: 4,519 lbs.
Wing Area: 174.375 sq. ft.
Armament: 4 x 7.9 mm. FN Browning machine guns/300 rpg.
Maximum Speed: 286 mph. (no altitude given).
Climb: 1,000 m./1.15 min. (2,853 fpm. avg.), 3,000 m./3.4 min. (2,916 fpm. avg. 1,000-3,000 m.),
6,000 m./7.5 2,400 fpm. (3,000-6,000 m.).
Service Ceiling: 37,900 ft.
Note: I would like to stress at this time that this is general published material. I do not have any official
documentation to validate any of these figures.
August 1938: One D.XXI powered by the Klimov M-25 flew at El Carmoli by the Spanish Republican forces
that managed to escape the Nationalist forces that overran the assembly plant in Spain. The M-25A was
capable of 725 hp. and the M-25V was capable of 750 hp. I do not know at this time which was installed
in the D.XXI produced in Spain at this time.
8 September 1939: The last of the original 36 ordered by the LVA are delivered.
30 November 1939: Russia invades Finland. The Finnish Air Force has forty-five D.XXIs on hand. Forty-one
D.XXIs were on strength with Fighter Squadron HLeLv.24.
1 December 1939: Lieutenant Eino Loukkanen in FR-104 recorded the first "kill" of an SB-2.
During 1939: Denmark ordered two D.XXIs and took out a manufacturing license for the Royal Army Aircraft
Factory in Copenhagen: Producing three aircraft in 1939 and 7 more in 1940. Engine was the Mercury
VI-S: 645 hp. and armament was 2 x 20 mm. Madsen cannon.
9 April 1940: The Danish Aviation Troops had eight D.XXIs in service with No.2 Eskadrille when
Germany invaded Denmark.
10 May 1940: Twenty-eight D.XXIs were operationally combat ready when Germany invaded the Netherlands.
There were heavy losses on the first day, however the Fokkers destroyed 37 of 55 invading Ju 52/3m
troop transports of KGr.zbV.9.
11 May 1940: Eleven D.XXIs were still operational and gathered together at Buiksloof.
14 May 1940: Eight Netherlands Fokkers were still operational.
1941: The Finnish government ordered production of fifty D.XXIs. The Bristol Mercury engines were no longer
available. Pratt & Whitney R-1535 twin wasps were used. The vertical tail surface was increased. The
engine bearers were shortened to maintain the center of gravity due to the heavier engine. The fuselage
guns were moved to the wings. The canopy was extended to improve pilot vision. P&W 1535: 825 hp.
Wing Area: 172.223 sq. ft.
Armament: 4 x 7.9 mm. in wings.
Combat Weight: 4.821 lbs.
Maximum Speed: 272 mph./9,000 ft. (438 kph./2,743 m.)
Climb: 1,000 m./1.4 min (2,343 fpm. avg.), 3,000 m./4.5 min. (2,117 fpm. avg. from 1,000 m.-3,000 m.)
The information on this aircraft has been very interesting to me. It is easy to get caught up in the
flamboyant fighters like the Spitfire, Mustang and Bf.109. It is another world all together when you research the rugged soldiers that trudged on early in the invasion like the D.XXI, B-534, Gladiator and many other unsung heroes that didn't have the state of art performance but manage to do their jobs past their so called
Edited by CORSNING, 20 March 2017 - 05:00 PM.