Neukom Elfe
{{Short description|Swiss glider}}
{{Use dmy dates|date=September 2022}}
{{Use British English|date=September 2022}}
| {{Infobox aircraft begin
| name=Elfe | image=Elfe 17a.jpg | caption=Neukom S-4 Elfe 17 }}{{Infobox aircraft type | type=Open Class and Standard Class sailplane | national origin=Switzerland | manufacturer=Neukom | designer=W. Pfenninger | first flight=1964 | introduced= | retired= | status= | primary user= | number built= | developed from= | variants with their own articles= }} |
The Neukom Elfe is family of Swiss single-seat high-performance sailplane designs.
The aircraft is a shoulder-wing cantilever monoplane with a wing made from a balsa and plywood sandwich covered in fiberglass and a fuselage built from plywood.{{cite web|url = http://www.sailplanedirectory.com/PlaneDetails.cfm?planeID=97|title = Elfe S-3 Neukom|access-date = 2008-09-05|last = Activate Media|year = 2006|url-status = dead|archive-url = https://web.archive.org/web/20071116052102/http://www.sailplanedirectory.com/planedetails.cfm?PlaneID=97|archive-date = 2007-11-16}}
Design and development
=Elfe and Elfe 2=
The first Elfe was a 9-metre wingspan glider that was designed by Swiss designer W. Pfenninger before World War II.
A new design was introduced by Pfenninger in 1947 and was named the Elfe 2. This was probably the first sailplane to feature a laminar flow airfoil. It crashed due to rudder flutter
=PM-3=
The Elfe series was then taken over, improved and strengthened by the Swiss engineer Markwalder into a third prototype, called the Elfe PM-3.Said, Bob: 1983 Sailplane Directory, Soaring Magazine, page 79. Soaring Society of America, November 1983. USPS 499–920
The sole PM-3's construction was started in one factory, but finished in another. It was first flown in 1955 and then went into storage for three years. The aircraft is built from Swiss pine and birch plywood and has a 52.5 foot wingspan. The PM-3 has dive brakes and full-span flaps with aileron interconnects to the flaps. It originally had fixed landing gear, but has been retrofitted with retractable mainwheel.
It was retrieved from storage and flown in Europe by Rene Compte who brought it to compete in the U.S. Nationals at El Mirage, Arizona, held in 1962. After the US Nationals the aircraft was not returned to Europe, but was sold, remained in the US and registered as N6351U in the Experimental – Exhibition/Racing category.{{cite web|url = http://registry.faa.gov/aircraftinquiry/NNumSQL.asp?verified=1&NNumbertxt=6351U|title = FAA Registry N-Number Inquiry Results|access-date = 2008-09-05|last = Federal Aviation Administration|author-link = Federal Aviation Administration|date=September 2008}} In 1999 the PM-3 was sold again and moved to the United Kingdom.{{cite web|url = http://www.sgolten.ch/uploads/media/Rhoenstei_2_2004_01.pdf|title = dr rhönstei|access-date = 2008-10-18|last = Clubzeitschrift der Segelfluggruppe Olten|year = 2004}}
Compte originally reported the glider as being very pleasant to fly, but it did not do well in weak soaring conditions. It performed well only in conditions of strong lift. The PM-3 has a glide ratio of 40:1.
=Elfe M and S series=
Albert Neukom then took over the design and developed the Elfe M, Elfe MN and the AN66.
The next in the line was the V-tailed Standard Elfe S-1, which first flew in 1964.
The second prototype, the S-2, was similar to the S-1, but had a conventional tail. The S-3 was the production version of the S-2 and was first flown in 1966 and entered production that same year. It had a cruciform tail, trailing edge airbrakes and a retractable main wheel.
In competition, a Standard Elfe that was flown by Markus Ritzi of Switzerland, placed second in the 1965 World Gliding Championships held at South Cerney, United Kingdom. United States pilot A. J. Smith finished first in the Standard Class at the 1968 World Gliding Championships held at Leszno, Poland in an S-3.
Variants
;Pfenninger Elfe
:Pre-World War II prototype
;Pfenninger Elfe 2
:1947 prototype
;Markwalder Elfe PM-3
:1955 prototype, competed in 1962 US Nationals
;Neukom Elfe M
:Early 1960s prototype
;Neukom Elfe MN-R
:Early 1960s prototype
:Early 1960s prototype
;Neukom S-1 Elfe
:Sailplane with a V-tail
;Neukom S-2 Elfe
:Sailplane with a conventional tail
:Production version of the S-2 with cruciform tail
:15 m wingspan
:17 m wingspan
;IPE Elfe IV{{harvnb|Pereira|1997|p=206}}
:Between 1978 and 1985, Indústria Paranaense de Estruturas built three.
Specifications (Elfe 15)
{{Aircraft specs
|prime units? = met
|crew=1
|length m=7.30
|length ft=23
|length in=11
|span m=15
|span ft=49
|span in=2
|height m=1.80
|height ft=5
|height in=11
|wing area sqm=11.80
|wing area sqft=127
|aspect ratio=19
|empty weight kg=230
|empty weight lb=507
|gross weight kg=350
|gross weight lb=772
|max speed kmh=210
|max speed mph=131
|sink rate ms=0.64
}}
See also
References
{{Reflist}}
- {{cite book |last= Taylor |first= Michael J. H. |title=Jane's Encyclopedia of Aviation |year=1989 |publisher=Studio Editions |location=London }}
- {{cite book|last=Pereira|first=Roberto|title=Enciclopédia de Aviões Brasileiros|year=1997|publisher=Editora Globo|location=São Paulo|isbn=9788525021373}}
External links
{{commons category|Neukom Elfe}}
- [http://membres.lycos.fr/wings2/galphot/elfe_s3.jpg Photo of Elfe S-1]
- [http://membres.lycos.fr/wings2/galphot/elfe_s4a.jpg Photo of Elfe S-4a]
- [http://membres.lycos.fr/wings2/galphot/elfe_17.jpg Photo of Elfe 17]
Category:1960s Swiss sailplanes