Heinkel HD 21

__NOTOC__ Infobox Aircraft
name=HD 21 and HD 29


caption=
type=Civil trainer
national origin=Germany
manufacturer=Heinkel
designer=
first flight=avyear|1924
introduced=
retired=
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variants with their own articles=The Heinkel HD 21 was a trainer aircraft built in Germany during the 1920s. It was a conventional single-bay biplane with staggered wings braced with N-struts. The main units of the fixed, tail-skid undercarriage were linked by a cross-axle, and the aircraft had three open cockpits in tandem, although one of these was typically faired over. The HD 29 of 1925 was essentially similar, but was purely a two-seater.

One HD 21 (registered "SE-ACY") was flown as an air ambulance by Carl Gustaf von Rosen for the Red Cross during the Italian invasion of Abyssinia in 1935. Others were flown by the Reichswehr at the clandestine aviation training facility in Lipetsk.

pecifications

aerospecs
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crew=Two, pilot and instructor
capacity=
length m=7.25
length ft=23
length in=9
span m=10.60
span ft=34
span in=9
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width m=
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height m=3.05
height ft=10
height in=0
wing area sqm=27.8
wing area sqft=299
swept area sqm=
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volume m3=
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aspect ratio=
empty weight kg=680
empty weight lb=1,500
gross weight kg=980
gross weight lb=2,160
lift kg=
lift lb=

eng1 number=1
eng1 type=Mercedes D.I
eng1 kw= 75
eng1 hp= 100
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max speed kmh=135
max speed mph=103
max speed mach=
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ceiling m=
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glide ratio=
climb rate ms=2.7
climb rate ftmin=530
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armament1=1 x .22 LR caliber built in machine pistol
armament2=2 x 100 .22 LR caliber links
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armament6= aircontent
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References

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