Editorial
Article Type: Editorial From: Aircraft Engineering and Aerospace Technology: An International Journal, Volume 82, Issue 3
Greetings to you, colleagues. This issue of Aircraft Engineering and Aerospace Technology is one that reflects the 70th anniversary of the Battle of Britain. The Battle of Britain began in July 1940, when the German Luftwaffe started attacking shipping in the English Channel. This quickly led to an intensification of air and sea warfare against the British homeland until the October of the same year. The German offensive served to introduce aircraft like the Hawker Hurricane, Supermarine Spitfire, Dornier Do 17, Heinkel He 111,Junkers Ju 87 and Messerschmitt Bf 109 into the public consciousness.
First World War was the era of innovation where many concepts were investigated using the “cut and try” approach to aircraft development. Many of these aircraft reflected a superior level of craftsmanship with relatively low production throughput. Second World War saw the emergence of what I refer to as “producible innovation”, namely, signs of the first tentative steps towards our contemporary notion of a define-assemble philosophy. Second World War, this new approach to aircraft development was borne from the need to expedite service entry through increased production throughput, assurance of repeatability in manufacturing as well as maintaining minimum quality levels.
This issue leads with a section dedicated to presenting three rather fascinating articles from Vol. 11 published in 1939:
- 1.
“Series Construction of the Hurricane I: A Review of the Methods of Hawker Aircraft Ltd”, Vol. 11 No. 2, pp. 61-71.
- 2.
“Quantity Production of the Spitfire I: Notes on the System Adopted by Vickers-Armstrongs Ltd”, Vol. 11 No. 4, pp. 167-180.
- 3.
“Some German Military Types: An Appreciation of the More Modern Types in Service, Together with Some Notes on their Development and Modification”,Vol. 11 No. 10, pp. 375-379, 382.
One aspect that strikes the reader, particularly when it concerns details about structural topology, bill-of-material and manufacturing techniques for the British Hurricane and Spitfire aircraft types, is the public dissemination of what would in our age be considered as highly classified information. Nonetheless, we are grateful for the fact that we can access such a valuable repository.
A contemporary account of British fabrication and manufacturing is presented in articles “Series Construction of the Hurricane I: A Review of the Methods of Hawker Aircraft Ltd” and “Quantity Production of the Spitfire I: Notes on the System Adopted by Vickers-Armstrongs Ltd”. Both aircraft are classic examples of built-up airframes. A notable difference between the two aircraft types was the all-metal, semi-monocoque construction of the Spitfire compared to the Hurricane characterised by a fabric-covered, Warren truss internal structural topology. Although a good number of Hurricanes with fabric-covered wings were in service during the Battle of Britain, many had all-metal, semi-monocoque versions retrofitted during servicing or repair. This alteration significantly expanded the flight envelope of the aircraft and facilitated a measure of combat related damage tolerance. One excellent example of emphasis on define-assemble is the ability to effect a wing change in only three hours for the Hurricane. The Spitfire, with its complex wing outer mould lines lofting placed an emphasis on minimising (vortex-induced and profile) drag in order to increase speeds during transversal and straight-and-level flight phases, does compromise the pace at which production can achieve learning-curve minima and the level of manufacturing throughput that could have been realised.
The article “Some German Military Types: An Appreciation of the More Modern Types in Service, Together with Some Notes on their Development and Modification”, provides a synopsis of many known and emerging German military aircraft of the time. A review of bombers, fighters and seaplanes developed by Dornier, Heinkel, Junkers and Messerschmitt is presented. Bombers like the Dornier Do 17, Heinkel He 111 and Junkers Ju 87 were the workhorses during the Blitz on Britain, especially London. One noteworthy attribute of the twin-engined Do 17 and the He 111 was the shortening of the nose: a good measure of experimentation occurred leading to a trade-off of streamlined forward fuselage shapes for sake of improved field of vision for the crew. The single-engined Ju 87 dive bomber embodied many innovative design features, which included amongst others inverted gull-wings (for improved pilot visibility and shortened landing gear height) and automatically deployed air-brakes fitted near the leading edge on the underside of the wing (to ensure constant speed dives and prevent extreme acceleration during pull-out from a dive). In terms of fighter aircraft, the Bf 109 demonstrates an alternative approach to aircraft development according to requirements spelled out for the Spitfire. Emphasis was placed on reducing parts count, simplicity in construction (for example, the straight tapered wing), and, design priority was placed on giving total and easy maintenance/service access during turn-around. A high wing-loading was implemented in order to promote greater in-flight speeds. This circumstance necessitated integration of novel features like leading edge slats and “drooped”ailerons for improved low-speed performance.
Since the Battle of Britain, the fourth generation of aerospace engineers find themselves working in a mature industry governed by highly refined set of procedures for function, synthesis and programme execution. As we take a retrospective look at the evolution of aerospace product development it is quite evident to see, and sadly so, that world warfare was the progenitor of what we all consider to be best practise today. In closing, on behalf of the Editorial Advisory Board and Editorial Team, it is our express wish you find Vol. 82 No. 3 interesting reading.
Askin T. Isikveren
