View source for Militär-Apparat MA-7

{|{{Infobox aircraft begin
|name = Militär-Apparat MA-7
|image = MA-7 b.JPG
|caption =
}}{{Infobox aircraft type
|type = [[Fighter aircraft]]
|manufacturer = [[Eidgenoessische Konstruktionswerkstaette|K & W]]
|designer = August Häfeli
|first flight = 1925
|introduced = February 1926
|retired = April 1926
|status =
|primary user = [[Swiss Air Force]]
|more users =
|produced =
|number built = 1
|unit cost =
|developed from =
|variants with their own articles =
|developed into =
}}
|}
The '''Militär-Apparat MA-7''', also known as the '''Häfeli MA-7''' and '''K & W MA-7''', was a prototype [[Fighter (aircraft)|fighter]] designed by August Häfeli in [[Switzerland]]. It flew in two different engine configurations, neither of which were deemed satisfactory and so the type did not enter series production. However, it did achieve a Swiss record for flying at an altitude of {{convert|9800|m|ft|abbr=off}} above sea level in 1926.
==Design and development==
Designed by August Häfeli in response to a [[Swiss Air Force]] requirement for an indigenous fighter design, the MA-7 was a biplane of fabric-covered wood construction with N-shaped wing struts like its predecessor the [[Fokker D.VI]] of 1918. Ailerons were installed only on the upper wing, which also contained an auxiliary gravity fuel tank. Power was provided by a {{convert|300|hp|kW|abbr=on}} [[Hispano-Suiza 8]]Fb HS42 [[V8 engine|V-8]] liquid-cooled engine manufactured in Switzerland under license. The aircraft was built by [[Eidgenoessische Konstruktionswerkstaette|K & W]] in 1925 and handed over for trials in February 1926.<ref name=balous>{{cite journal|last=Balous|first=Miroslav|title=K+W/Häfeli MA-7|journal=Letectví a kosmonautika|volume=85|year=2009|language=Czech|page=48}}</ref><ref name=urich>{{cite book|last1=Urech|first1=Jakob|last2=Hunziker|first2=Emil|title=Die Flugzeuge der Schweizerischen Fliegertruppe seit 1914|publisher=Hrsg. von der Abt. der Militärflugplätze Dübendorf, Verlag Th. Gut & Co, 1. Aufl. Stäfa|language=German|date=1974|page=134}}</ref>
The prototype was returned to the manufacturer in April 1926 due to unsatisfactory flight characteristics and performance. K & W responded with the installation of an indigenous {{convert|400|hp|abbr=on}} [[LFW-12 X-1]] engine. This, however, proved too large and heavy for the frame and entire MA-7 project was subsequently discontinued. The Swiss Air Force procured the French [[Dewoitine D.1]] as their replacement fighter instead.<ref name=balous/>
==Records==
On 23 April 1926, test pilot Max Cartier set a Swiss record of {{convert|9800|m|ft|abbr=off}} above sea level with the MA-7.<ref name=dietschi>{{cite journal|first=Von Willy|last=Dietschi|title=Oltner Flugpioere|journal=Oltner Neujahrsblätter|volume=18|page=16|year=1960|language=German|url=https://www.e-periodica.ch/digbib/view?pid=olt-001:1960:18|accessdate=5 February 2020}}</ref>
==Operators==
;{{SUI}}
* [[Swiss Air Force]]
==Specifications==
{{Aircraft specs
|ref=Urech & Hunziker, 1974<ref name=urich/> Fader, 2013<ref>{{cite web|first=Michael E.|last=Fader|title=Häfeli Militär Apparat MA-7|website=wings-aviation.ch|year=2013|url=http://www.wings-aviation.ch/16-SAF/2-Aircraft/Militaerapparat/Ma-7.htm|accessdate=5 February 2020}}</ref>
|prime units?=met<!-- imp or kts first for US aircraft, and UK aircraft pre-metrification, met(ric) first for all others. You MUST choose a format, or no specifications will show -->
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|crew=One
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|length m=6.61
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|span m=9.91
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|wing area sqm=23.75
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|empty weight kg=843
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|gross weight kg=1213
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|eng1 number=1
|eng1 name=[[Hispano-Suiza 8]]Fb HS-42
|eng1 type=V8, liquid-cooled [[aircraft engine]]
|eng1 kw=<!-- prop engines -->
|eng1 hp=300<!-- prop engines -->
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|max speed kmh=235
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|cruise speed kmh=255
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|range km=300
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|ceiling m=7600
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==See also==
{{Aircontent|
|similar aircraft=
*[[Fairey Firefly I]]
*[[Fokker D.IX]]
|sequence=
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|see also=
}}
==References==
{{Reflist}}
{{Authority control}}
[[Category:1920s Swiss fighter aircraft]]
[[Category:Single-engined tractor aircraft]]
[[Category:Biplanes]]
[[Category:Aircraft first flown in 1926]]