Atlas D Missile Countdown T-15 to Launch 1961 US Air Force Training Film FTA-446 (Patreon)

more at http://quickfound.net/

Originally a public domain film from the National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.

The film was silent. I have added MIDI classical piano music (Beethoven Piano Sonata No. 5 in C minor Opus 10) produced by Bernd Krueger, from http://www.piano-midi.de licensed under the cc-by-sa Germany License: http://creativecommons.org/licenses/by-sa/3.0/de/deed.en

https://en.wikipedia.org/wiki/SM-65_Atlas

Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/

The SM-65 Atlas was the first operational intercontinental ballistic missile (ICBM) developed by the United States and the first member of the Atlas rocket family. It was built for the U.S. Air Force by the Convair Division of General Dynamics at an assembly plant located in Kearny Mesa, San Diego). Atlas became operational as an ICBM in October 1959 and was quickly obsoleted by new development, being retired as a missile by 1965. The Atlas required extremely long preparation times which made it unsuitable for a quick launch ICBM. However, this was not a requirement for planned space launches, and so Atlas-derived launch vehicles served a long history as space launchers...

https://en.wikipedia.org/wiki/SM-65D_Atlas

The SM-65D Atlas, or Atlas D, was the first operational version of the U.S. Atlas missile. Atlas D was first used as an intercontinental ballistic missile (ICBM) to deliver a nuclear weapon payload on a suborbital trajectory. It was later developed as a launch vehicle to carry a payload to low Earth orbit on its own, and later to geosynchronous orbit, to the Moon, Venus, or Mars with the Agena or Centaur upper stage.

Atlas D was launched from Cape Canaveral Air Force Station, at Launch Complexes 11, 12, 13 and 14, and Vandenberg Air Force Base at Launch Complex 576.

The fully operational D-series Atlas was similar to the R&D model Atlas B and C, but incorporated a number of design changes implemented as a result of lessons learned during test flights. In addition, the D-series had the full-up Rocketdyne MA-2 propulsion system with 360,000 pounds of thrust versus the 250,000 pounds of thrust in the Atlas B/C's engines. Operational Atlas D missiles retained radio ground guidance aside from a few R&D launches which tested the inertial guidance system designed for the Atlas E/F, and the Atlas D would be the basis for most space launcher variants of Atlas...

Most Atlas D launches were sub-orbital missile tests; however several were used for other missions, including orbital launches of crewed Mercury, and uncrewed OV1 spacecraft. Two were also used as sounding rockets as part of Project FIRE. A number were also used with upper stages, such as the RM-81 Agena, to launch satellites.

The Atlas D was deployed in limited numbers as an ICBM due to its radio guidance while the fully operational E and F-series missiles had inertial guidance packages and a different ignition system that allowed faster engine starts.

For Mercury, the Atlas D was used to launch four crewed Mercury spacecraft into low Earth orbit. The modified version of the Atlas D used for Project Mercury was designated Atlas LV-3B.

Atlas Ds used for space launches were custom-built for the needs of the mission they were performing, but when the Atlas was retired from missile service in 1965, Convair introduced a standardized Atlas vehicle (the SLV-3) for all space missions. Remaining D-series missiles were flown until 1967 for suborbital tests of reentry vehicles and a few space launches.

A total of 116 D-series missiles (not including vehicles used for space launches) were flown from 1959–67 with 26 failures.

Warhead

The warhead of the Atlas D was originally the G.E. Mk 2 "heat sink" re-entry vehicle (RV) with a W49 thermonuclear weapon, combined weight 3,700 lb (1,680 kg) and yield of 1.44 megatons (Mt). The W-49 was later placed in a Mk 3 ablative RV, combined weight 2,420 lb (1,100 kg) The Atlas E and F had an AVCO Mk 4 RV containing a W-38 thermonuclear bomb with a yield of 3.75 Mt which was fuzed for either air burst or contact burst. The Mk 4 RV also deployed penetration aids in the form of mylar balloons which replicated the radar signature of the Mk 4 RV. The Mk 4 plus W-38 had a combined weight of 4,050 lb (1,840 kg)...