Armstrong Whitworth F.K.7 and F.K.8
For a description of the format and data included in Production Tables, see here.
Type Description and Production Data
| F.K.7 | F.K.8 | Fleet F.R. Biplane | 'Improved' F.K.8 |
F.K.7
Two-seat general-purpose, two bay biplane, with a conventional wooden wire-braced airframe with fabric covering, the dihedral of the upper wing was greater than that of the lower. It featured the relatively complicated undercarriage of the F.K.3 with its vertically sprung main legs. The engine had a short vertical outlet on the exhaust manifold, and the cooling system had two long upright radiator elements, their upper halves meeting in an inverted V at the wing leading edge. The tail unit the surfaces were similar to the F.K.3, the rudder having a long pointed horn balance. Like the earlier F.K.2, it had separate cockpits for the pilot and observer, with the latter in front. One 160 h.p. Beardmore powerplant.
Production Details
| Serial Range | C/n | Batch Qty |
Conv. | Canc'd | Notes |
| 49 aircraft ordered from Armstrong Whitworth, Gosforth, to Contract 87/A/382. Cancelled. See Note 1. | |||||
| A729 - A777 | 49 | See note 1 | |||
| 1 aircraft ordered from Armstrong Whitworth, Gosforth, to Contract 87/A/508. See Note 1. | |||||
| A411 | 630 | 1 | Renumbered A2683 | ||
| Total Production | 1 | 49 | |||
F.K.8
Production derivative of the F.K.8, with the addition of a forward-firing .303 in Vickers machine gun to port of and slightly behind the engine. The Armstrong Whitworth gun synchronising mechanism was incomplete at the time the first example A2636 arrived in France and some early production F.K.8s may have used the Arsiad interrupter gear instead. The Armstrong Whitworth mechanism proved unreliable and was later replaced by the Constantinescu gear. From the fifth production aircraft, the rudder balance was shortened and the shape of the fin was modified. One 140 h.p RAF4a or 150 h.p. Lorraine Dietrich powerplant.
In service, the complex Armstrong Whitworth undercarriage was relaced by that from the Bristol Fighter when aircraft were passed to a Maintenance Unit for repair. In similar fashion to its forebare the F.K.3, the F.K.8 became known as the "Big Ack".
In service, the complex Armstrong Whitworth undercarriage was relaced by that from the Bristol Fighter when aircraft were passed to a Maintenance Unit for repair. In similar fashion to its forebare the F.K.3, the F.K.8 became known as the "Big Ack".
| F.K.8 (RAF4a) Specification | |||||||||
| Span | Length | Height | Wing Area | Empty Wt | Max AUW | Cruise Speed | Maximum Speed | Endurance | Service Ceiling |
| 43 ft 6 in | 31 ft | 11 ft 3 in | 540 sq ft | 1916 lb | 2811 lb | 95 mph/ 83 kn | 3 hr | 13000 ft | |
| 13.26 m | 9.45 m | 3.43 m | 50.17 m2 | 869 kg | 1275 kg | 153 km/h | 3962 m | ||
Production Details
| Serial Range | C/n | Batch Qty |
Conv. | Canc'd | Notes |
| 250 aircraft ordered from Armstrong Whitworth, Gosforth, to Contract 87/A/508, completed November 1917. See Note 1. | |||||
| A2684 - A2732 | 49 | Originally begun as F.K.7's A729 - A777 to contract 87/A/382. A2684 was initially marked A729. | |||
| A9980 - A9999 | 20 | ||||
| B201 - B330 | 130 | ||||
| B5751 - B5801 | 51 | ||||
| 400 aircraft ordered from Armstrong Whitworth, Gosforth, to Contract AS.13163, Requisitions 65, 107 and 200. Completed October 1918. | |||||
| B3301 - B3400 | 100 | ||||
| B5802 - B5850 | 49 | ||||
| C8401 - C8651 | 251 | 200 aircraft to contract AS.25709 | |||
| 200 aircraft ordered from Angus Sanderson and Co. Ltd., Newcastle-upon-Tyne, to Contract AS.3390, Requisitions 12 and 30. Completed March 1918. | |||||
| C3507 - C3706 | 200 | ||||
| 200 aircraft ordered from Angus Sanderson and Co. Ltd., Newcastle-upon-Tyne, to Contract AS.34715, Requisition 251. Completed July 1918. | |||||
| D5001 - D5200 | 200 | ||||
| 50 aircraft ordered from Armstrong Whitworth, Gosforth, to Contract AS.2892, Requisition 324. Completed June 1918. | |||||
| E8807 - E8856 | 50 | ||||
| 50 aircraft ordered from Angus Sanderson and Co. Ltd., Newcastle-upon-Tyne, to Contract 35a/1089/C922, Requisition 473. Completed August 1918. | |||||
| F3442 - F3491 | 50 | ||||
| 50 aircraft ordered from Armstrong Whitworth, Gosforth, to Contract 35a/1088/C921, Requisition 472. Completed August 1918. | |||||
| F4221 - F4270 | 50 | ||||
| 200 aircraft ordered from Angus Sanderson and Co. Ltd., Newcastle-upon-Tyne, to Contract 35a/1710/C1819. Completed October 1918. | |||||
| F7347 - F7546 | 200 | ||||
| 300 aircraft ordered from Angus Sanderson and Co. Ltd., Newcastle-upon-Tyne, to Contract 35a/2235/C2569, Requisition 617. Completed March 1919. | |||||
| H4425 - H4724 | 300 | ||||
| Total Production | 1700 | ||||
Known F.K.8 Rebuilds
| Serial Range | Qty | Notes |
| B1497 | (1) | Built from spares by 18th Wing ARS |
| B4014 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4017 - B4018 | (2) | Built from spares and salvage by No.2 (Northern) ARD |
| B4049 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4061 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4080 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4108 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4120 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4145 - B4150 | (6) | Built from spares and salvage by No.2 (Northern) ARD |
| B4154 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4156 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4160 - B4161 | (2) | Built from spares and salvage by No.2 (Northern) ARD |
| B4163 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4165 - B4167 | (3) | Built from spares and salvage by No.2 (Northern) ARD |
| B4169 - B4170 | (2) | Built from spares and salvage by No.2 (Northern) ARD |
| B4172 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4174 - B4177 | (4) | Built from spares and salvage by No.2 (Northern) ARD |
| B4179 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4185 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4187 - B4188 | (2) | Built from spares and salvage by No.2 (Northern) ARD |
| B4190 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4194 - B4195 | (2) | Built from spares and salvage by No.2 (Northern) ARD |
| B4198 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B4200 | (1) | Built from spares and salvage by No.2 (Northern) ARD |
| B8068 | (1) | Built from salvage by No.1 (Southern) ARD |
| B856 | (1) | Rebuilt from salvage by No1 (Southern) ARD |
| B870 - B871 | (2) | Rebuilt from salvage by No1 (Southern) ARD |
| F5801 - F5808 | (8) | Rebuilds, ex-B5783, C3627, B5758, (?), C3650, C3641, C3508. CB4331 |
| F6124 | (1) | Rebuilt at depot in France, ex-C8601 |
| F6137 | (1) | Rebuilt at depot in France, ex·B5836 |
| F6159 - F6163 | (5) | Rebuilt at depot in France, ex C3646, B3317, C8503, C8435, D5003 |
| F616 - F618 | (3) | Built from spares by No.2 (Northern) ARD |
| F622 - F623 | (2) | Built from spares by No.2 (Northern) ARD |
| F625 - F628 | (4) | Built from spares by No.2 (Northern) ARD |
| F631 - F634 | (4) | Built from spares by No.2 (Northern) ARD |
| F638 | (1) | Built from spares by No.2 (Northern) ARD |
| F642 | (1) | Built from spares by No.2 (Northern) ARD |
| F644 | (1) | Built from spares by No.2 (Northern) ARD |
| F646 - F647 | (2) | Built from spares by No.2 (Northern) ARD |
| F649 - F651 | (3) | Built from spares by No.2 (Northern) ARD |
| H7156 - H7157 | (2) | Rebuilt in France |
| C4550 | (1) | Built from spares by 18th Wing. |
| C9997 | (1) | Built frorn spares by 24th Wing ARS |
| Total Rebuilds (83) | ||
Ex-RAF F.K.8 Rebuilt For Export
| Serial Range | C/n | Qty | Notes |
| 1 aircraft supplied to the Paraguayan Government. Delivered 1922. | |||
| (1) | 'Pres. Ayala' marked on fuselage side. | ||
| Total Production | (1) | ||
U.K. Civil Registered F.K.8
| C/n | Initial Registration |
Military Serial | Notes |
| 8 aircraft converted to civil by the Handley Page or the Aircraft Disposal Company. | |||
| G-EAET | D5150 | To London and Provincial Aviation Co. | |
| G-EAIC | H4473 | To T.N. Stack | |
| G-EAJS | H4612 | To Lt. Col G.H.P. Henderson | |
| G-EALW | F7484 | To By Air Ltd. | |
| G-EATO | F7384 | To Robin Duke via ADC; converted to a three-seater by Robert Noorduyn. | |
| G-EATP | H4600 | To Major T. Gran | |
| G-EAVQ | H4585 | To Handley Page Ltd | |
| G-EAVT | H4573 | To Handley Page Ltd | |
| Total Conversions (8) | |||
Australian Civil Registered F.K.8
| C/n | Initial Registration |
Military Serial | Notes |
| 3 aircraft converted to civil by the Handley Page or the Aircraft Disposal Company. | |||
| G-AUCF | H4561 | To Commercial Aviation Co, Rochester, Victoria, June 1921; to Queensland and Northern Territories Aerial Services Ltd, Sept 1922. | |
| G-AUCS | ?? | To Aviation Ltd, Glenroy, Victoria, June 1921; later to Queensland and Northern Territories Aerial Services Ltd, Oct 1923. | |
| G-AUDE | F4231 | To Simpson and Tregilles Aircraft and Transport Co, Perth, June 1921; later to Queensland and Northern Territories Aerial Services Ltd, Sept 1922. |
|
| Total Conversions (3) | |||
Fleet F.R. Biplane
Naval fighter reconnaissance derivative of F.K.8, with more voluminous fuselage and larger fin and rudder. One 200 h.p. Sunbeam powerplant (most probably the Sunbeam Afridi).
Production Details
| Serial Range | C/n | Batch Qty |
Conv. | Canc'd | Notes |
| 1 aircraft built by Armstrong Whitworth, Gosforth, for the RNAS to Contract AS.6285(3). Completed March 1917 but not accepted. | |||||
| N513 | 1 | See note 2 | |||
| Total Production | 1 | ||||
'Improved' F.K.8
As F.K.8 with modified cooling system, undercarriage and exhaust manifolds. 160 h.p. Beardmore powerplant.
Production Details
| Serial Range | C/n | Batch Qty |
Conv. | Canc'd | Notes |
| One unnamed experimental "Improved F.K.8" built by Armstrong Whitworth, Gosforth. Initially retained by Armstrong Whitworth, delivered to No.1 ASD in January 1918. | |||||
| none | 1 | Eventually received serial B6901 in March 1918. | |||
| Total Production | 1 | ||||
Production Summary
All Aircraft By Type
| Constructor | F.K.7 | F.K.8 | Fleet F.R. Biplane |
"Improved" F.K.8 |
||
| Built | Canc'd | Built | Canc'd | |||
| Armstrong Whitworth | 1 | 49 | 750 | 1 | 1 | |
| Hewlett and Blondeau | 950 | |||||
| 1 | 49 | 1700 | 0 | 1 | 1 | |
Air Board Contracts Associated with F.K.7 and F.K.8 Production
| Contract | Date | Requisition | Constructor | Type | Total |
| 87/A/382 | Armstrong Whitworth | F.K.7 | 0 | ||
| 87/A/508 | Aug 1916 | Armstrong Whitworth | F.K.7 | 1 | |
| 87/A/508 | Aug 1916 | Armstrong Whitworth | F.K.8 | 250 | |
| AS.6285 | Nov 1916 | 241 | Armstrong Whitworth | Fleet F.R. Biplane | 1 |
| AS.13163 | Apr 1917 | 65, 107 and 200 | Armstrong Whitworth | F.K.8 | 200 |
| AS.25709 | Jan 1900 | 65, 107 and 200 | Armstrong Whitworth | F.K.8 | 200 |
| AS.3390 | Sep 1917 | 12 and 30 | Angus Sanderson | F.K.8 | 200 |
| AS.2892 | Dec 1917 | 251 | Angus Sanderson | F.K.8 | 50 |
| 35a/1088/C921 | Apr 1918 | 324 | Armstrong Whitworth | F.K.8 | 50 |
| 35a/1089/C922 | May 1918 | 472 | Armstrong Whitworth | F.K.8 | 50 |
| 35a/1710/C1819 | May 1918 | 473 | Angus Sanderson | F.K.8 | 200 |
| 35a/2235/C2569 | Jul 1918 | Angus Sanderson | F.K.8 | 300 |
Notes
- From Bruce [3]: "(An) official record of aeroplane contracts uncompleted at April 30 1916 includes ‘MA/Misc/1179 for 10 Armstrong Biplanes (160 Beardmore)', but that might more probably have been a file reference rather than a contract number. . . It appears that there might have been some administrative confusion over the early contracts for the 160 h.p. ArmstrongWhitworth two-seater. There is no known trace of any contract for the 10 aircraft proposed under the reference MA/Misc/1179. As at June 30 1916 a tender was in under the Contract reference number 87/A/508. This was for ‘150 Armstrong biplanes, 160 Beardmore'; and apparently the F.K.7 prototype was considered to have been supplied against it. One official record indicates that Contract 87/A/508 was confirmed and dated August 1 1916; another that the serial numbers A2683 - A2782, later A9980 - A9999 and 8201 - B330, were allocated for the 150 aircraft. However, an earlier (and possibly premature) contract, No.87/A/382, had existed, with serial numbers A729 - A777 allocated early in June 1916, apparently before A411 went to CPS for official evaluation. The aircraft total of 49 suggests that regard was had to the existence of A411."
- Later alloted serial H4424 against contract (or possibly file number) AS.27755/1 but allocation cancelled [3].
- Contract AS.1252 per Bruce [3], AS.6285 per Sturtivant and Page [5].
Production References
- Armstrong Whitworth Aircraft Since 1913, Oliver Tapper (Putnam, 1973)
- The Aeroplanes of the Royal Flying Corps, J.M. Bruce (Putnam, 1982)
- Windsock Mini Datafile 13, The AW FK.3, J.M. Bruce (Albatross Productions, 1998)
- British Military Aircraft Serials, 1878 - 1987, Bruce Robertson (Midland Counties Publishing, 1987)
- Royal Navy Aircraft Serials and Units, 1911-1919, Ray Sturtivant and Gordon Page (Air-Britain Publications, 1992)
- Contract ledger in AIR 20/761 via http://www.airhistory.org.uk/rfc/aircraft.html
Page Revision History
Revised at Version 2.0.0- Added Type Description and Specification details.
- Added Requisition Numbers.
- Added Contract Table.
- Added export F.K.8
- Added civil registered F.K.8
- Added note 3