Keystone Pronto
{{short description|1920s US mail plane design}}
| {{Infobox Aircraft Begin
| name=K-55 Pronto | image=Keystone Pronto Aero Digest April 1928.jpg | caption= }}{{Infobox Aircraft Type | type=Mail plane | national origin=United States | manufacturer=Keystone Aircraft | designer= | first flight=1927 | introduced= | retired= | status= | primary user=Peruvian Navy | number built= | developed from= | variants with their own articles= }} |
The Keystone K-55 Pronto was a mail plane developed in the United States in the late 1920s.
Design and development
The Pronto was a conventional single-bay, unequal-span biplane design with slightly staggered wings. The pilot sat in an open cockpit, in tandem with a second cockpit that could carry two passengers side-by-side. The fixed, tailskid undercarriage had divided main units.
A number of these aircraft were purchased by the government of Peru. Operated by the aviation arm of the Peruvian Navy, these aircraft initiated the first airmail service into the Peruvian Amazon. The first flight of this service was made by two Prontos, piloted by Leonardo Alvariño Herr and Harold B. Grow from Lima to San Ramón on 26 October 1927.
At least one Peruvian Pronto was fitted with pontoons and used to survey the Amazon River for locations suitable for seaplane operations.
In the Colombia-Peru War one Peruvian K-55 flown by Lieutenant Suero was captured by the Colombian Army.
Operators
;{{flag|Peru}}
Specifications
File:Keystone_K-55_Pronto_3-view_Le_Document_aéronautique_April,1928.png
{{Aircraft specs
|ref=Jane's all the World's Aircraft 1928{{cite book |title=Jane's all the World's Aircraft 1928 |editor1-last=Grey |editor1-first=C.G. |year=1928 |publisher=Sampson Low, Marston & company, ltd |location=London |page=232c}}
|prime units?=imp
|crew=1
|capacity=2 pax
|length m=8.15
|span m=11.8
|height m=
|height ft=
|height in=
|height note=
|wing area sqft=365
|aspect ratio=
|airfoil=Göttingen 398
|empty weight lb=1975
|empty weight note=landplane; {{cvt|2375|lb}} floatplane
|gross weight lb=3285
|gross weight note=landplane; {{cvt|3685|lb}} floatplane
|max takeoff weight kg=
|max takeoff weight lb=
|max takeoff weight note=
|fuel capacity={{cvt|72|USgal|impgal l}} in two upper wing tanks
|more general=
|eng1 number=1
|eng1 name=Wright J-5 Whirlwind
|eng1 type=9-cylinder air-cooled radial piston engine
|eng1 hp=220
|prop blade number=2
|prop dia m=
|prop dia ft=
|prop dia in=
|prop dia note=
|max speed mph=112
|max speed note=landplane at {{cvt|3204|lb}}; {{cvt|106|mph|kn km/h}} floatplane at {{cvt|3204|lb}}
|cruise speed kmh=
|cruise speed mph=
|cruise speed kts=
|cruise speed note=
|stall speed mph=37
|stall speed note=landplane
|never exceed speed kmh=
|never exceed speed mph=
|never exceed speed kts=
|never exceed speed note=
|range miles=500
|ferry range km=
|ferry range miles=
|ferry range nmi=
|ferry range note=
|endurance=
|ceiling m=
|ceiling ft=
|ceiling note=
|g limits=
|roll rate=
|climb rate ftmin=800
|time to altitude={{cvt|10000|ft}} in 16 minutes 30 seconds landplane; {{cvt|10000|ft}} in 40 minutes floatplane;
|wing loading lb/sqft=9
|wing loading note=landplane; {{cvt|10.1|lb/sqft|kg/m2}} floatplane
|fuel consumption kg/km=
|fuel consumption lb/mi=
|power/mass={{cvt|0.0685|hp/lb|kW/kg}} landplane; {{cvt|0.0625|hp/lb|kW/kg}} floatplane
|more performance=
}}
References
{{reflist}}
Further reading
- {{cite book |last= Taylor |first= Michael J. H. |title=Jane's Encyclopedia of Aviation |year=1989 |publisher=Studio Editions |location=London |page=560 }}
External links
{{commons category|Keystone K.55 Pronto}}
- [http://aerofiles.com/_keys.html aerofiles.com]
{{Keystone aircraft}}