Sikorsky R-4: Perbedaan antara revisi
Konten dihapus Konten ditambahkan
k Bot: Perubahan kosmetika |
Rescuing 1 sources and tagging 0 as dead.) #IABot (v2.0.8 |
||
Baris 49:
* [http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=518 Sikorsky R-4 page at the National Museum of the United States Air Force]
* [http://www.rafmuseum.org.uk/sikorsky-r-4b-hoverfly-1.htm RAF Museum Sikorsky R4 Hoverfly webpage]
* [http://www.plastikowe.pl/galerie/lotnictwo/sikorsky-r-4b-hoverfly-i Photo gallery of Sikorsky R-4B Hoverfly I] {{Webarchive|url=https://web.archive.org/web/20071202060801/http://www.plastikowe.pl/galerie/lotnictwo/sikorsky-r-4b-hoverfly-i |date=2007-12-02 }}
* [http://www.IndianaMilitary.org/ Freeman AAF contains the story of America's first Helicopter School]
* [http://www.helis.com/database/model/251/ HELIS.com Sikorsky R-4/HNS-1/Hoverfly I Database]
| |||