Milestone-Proposal:Appolo 11 Unified S-Band Transponder

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Docket #:2017-12</div> This is a draft proposal, that has not yet been submitted. To submit this proposal, click on "Edit with form", check the "Submit this proposal for review" box at the bottom, and save the page.

To the proposer’s knowledge, is this achievement subject to litigation? No

Is the achievement you are proposing more than 25 years old? Yes

Is the achievement you are proposing within IEEE’s designated fields as defined by IEEE Bylaw I-104.11, namely: Engineering, Computer Sciences and Information Technology, Physical Sciences, Biological and Medical Sciences, Mathematics, Technical Communications, Education, Management, and Law and Policy. Yes

Did the achievement provide a meaningful benefit for humanity? Yes

Was it of at least regional importance? Yes

Has an IEEE Organizational Unit agreed to pay for the milestone plaque(s)? No

Has an IEEE Organizational Unit agreed to arrange the dedication ceremony? No

Has the IEEE Section in which the milestone is located agreed to take responsibility for the plaque after it is dedicated? No

Has the owner of the site agreed to have it designated as an IEEE Milestone? No

Year or range of years in which the achievement occurred:


Title of the proposed milestone:

Apollo 11 Unified S-Band Transponder, 1969

Plaque citation summarizing the achievement and its significance:

On July 20, 1969, Neil Armstrong, 225,000 miles from Earth, stepped onto the lunar surface and uttered the now famous words – “That’s one small step for man, one giant leap for mankind.” Those eleven words, plus imagery, control commands, and tracking information for multiple lunar modules, were beamed to Earth by an S-band transponder designed and built by Motorola Government Electronics Division, Scottsdale, AZ.

In what IEEE section(s) does it reside?

Region 6 Scottsdale, Arizona Section TBD

IEEE Organizational Unit(s) which have agreed to sponsor the Milestone:

IEEE Organizational Unit(s) paying for milestone plaque(s):

IEEE Organizational Unit(s) arranging the dedication ceremony:

IEEE section(s) monitoring the plaque(s):

Milestone proposer(s):

Proposer name: Proposer's name masked to public
Proposer email: Proposer's email masked to public

Please note: your email address and contact information will be masked on the website for privacy reasons. Only IEEE History Center Staff will be able to view the email address.

Street address(es) and GPS coordinates of the intended milestone plaque site(s):


Describe briefly the intended site(s) of the milestone plaque(s). The intended site(s) must have a direct connection with the achievement (e.g. where developed, invented, tested, demonstrated, installed, or operated, etc.). A museum where a device or example of the technology is displayed, or the university where the inventor studied, are not, in themselves, sufficient connection for a milestone plaque.

Please give the address(es) of the plaque site(s) (GPS coordinates if you have them). Also please give the details of the mounting, i.e. on the outside of the building, in the ground floor entrance hall, on a plinth on the grounds, etc. If visitors to the plaque site will need to go through security, or make an appointment, please give the contact information visitors will need. The intended site is the original campus of Motorola Government Electronics Division, located just east of the intersection of Hayden Road and McDowell Road, Scottsdale, AZ. This campus is now occupied by General Dynamics. Due to the nature of GD's operation, the grounds are open to the public, but internal spaces are generally not.

Are the original buildings extant?


Details of the plaque mounting:


How is the site protected/secured, and in what ways is it accessible to the public?

TBD - based on final selection of site and mounting details.

Who is the present owner of the site(s)?

General Dynamics

What is the historical significance of the work (its technological, scientific, or social importance)?

Communications requirements for American manned space flights grew increasingly complex with each new mission and program. However, Apollo 11 introduced requirements not present in any of the early Apollo flights - deliver and recover a crew of astronauts a great distance from Earth and conduct extravehicular activities, while controlling and tracking multiple manned modules, simultaneously. The USB transponder had been investigated by Jet Propulsion Laboratory (JPL) previously, and was deemed, in earlier missions in the series, as a necessary enhancement to the program so as to be prepared for the lunar landing missions later in the series.

What obstacles (technical, political, geographic) needed to be overcome?

Existing systems for command, control, communications, and tracking needed to be combined into a single system, not just for one extraterrestrial vehicle, but up to three (Command Module, Lunar Lander, and Lunar Rover) in multiple flights within the Apollo series. Time was of the essence - primarily due to political factors (Space Race) - and proposed solutions could not require the development of new technologies. The JPL experiences were viewed as providing a superior technological solution with minimal new development. Additionally, earth-based tracking stations would have to be augmented with a number of major sites to maintain a "clear view" of the flight vehicles, both en-route to and from the moon, and while loitering in lunar orbit, or performing operations on the lunar surface. The concept of a re-insertion into lunar orbit for the return of the landing craft, with its occupants, to the orbiting command and service module was untested prior to the Apollo series- very precise, and timely tracking data was mandatory for success.

What features set this work apart from similar achievements?

Everything had to work the first time - design and operational parameters left little to no room for error or contingencies. With the lunar landing module separating from the command module, there were two spacecraft to be tracked simultaneously - the command module parked in a lunar orbit, and the lunar landing module transitioning between lunar orbit and the lunar surface. Very precise, real-time tracking of both were crucial for the lunar landing as well as the return to lunar orbit and docking with the command module.

References to establish the dates, location, and importance of the achievement: Minimum of five (5), but as many as needed to support the milestone, such as patents, contemporary newspaper articles, journal articles, or citations to pages in scholarly books. You must supply the texts or excerpts themselves, not just the references. At least one of the references must be from a scholarly book or journal article.

NASA SP-87 Proceedings of the APOLLO Unified S-Band Technical Conference, Goddard Spaceflight Center, July 14-15, 1965 Page 3, Abstract

Supporting materials (supported formats: GIF, JPEG, PNG, PDF, DOC): All supporting materials must be in English, or if not in English, accompanied by an English translation. You must supply the texts or excerpts themselves, not just the references. For documents that are copyright-encumbered, or which you do not have rights to post, email the documents themselves to Please see the Milestone Program Guidelines for more information.


Please email a jpeg or PDF a letter in English, or with English translation, from the site owner(s) giving permission to place IEEE milestone plaque on the property, and a letter (or forwarded email) from the appropriate Section Chair supporting the Milestone application to with the subject line "Attention: Milestone Administrator." Note that there are multiple texts of the letter depending on whether an IEEE organizational unit other than the section will be paying for the plaque(s).