During the Vietnam War, inadequacies within the USAF fleet of KC-135
air-refuelers were brought to light, and so the KC-10 Extender was developed as
result. Here's a rather picturesque McDonnell Douglas promo photo showing the first two KC-10s built for the US Air Force during an early test flight over the Mojave Desert, waaaaaay back in the early 1980s. The jet closest to the camera is the first KC-10A, USAF serial 79-0433 (though here she wears the civil registration N110KC), while the other is Extender number two, 79-0434.
Drink up and enjoy...
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