Slate Set for 2001 Nominations for ION Officers
___________________

The following nominations were submitted by the 2001 Nomination Committee for officers of The Institute of Navigation. The nominations committee was chaired by Prof. Per Enge and included two representatives from each region.

President
Mr. Ronald R. Hatch, Navcom Technology, Inc.
Executive Vice President
Mr. Len Jacobson, Global Systems and Marketing and Dr. Rodolph Kalafus, Trimble Navigation, Ltd.
Treasurer
Mr. Larry Hothem, U.S. Geological Survey
Eastern Region Vice President
Ms. Sally Frodge, U.S. Department of Transportation and Mr. Stephen Malys, National Imaging and Mapping Agency
Central Region Vice President
Dr. Chris Bartone, Ohio University., and Maj. John Raquet, Ph.D., Air Force Institute of Technology
Western Region Vice President
Mr. John Lavrakas, Overlook Systems Technologies and Dr. A.J. Van Dierendonck, AJ Systems
Eastern Council Member-at-Large
Dr. Anthea Coster, MIT Lincoln Laboratory and Mr. Marvin May, ARL, Penn. State
Central Council Member-at-Large
Dr. Boris Pervan, Illinois Institute of Technology and Dr. Lee Ott, Omnistar, Inc.
Western Council Member-at-Large
Dr. Sam Pullen, Stanford University and Mr. Patrick Fenton, Novatel, Inc.
Space Representative
Mr. Frank Czopek, The Boeing Company and Lt. Col. Mikel Miller, Ph.D., Air Force Inst. of Technology
Air Representative
Mr. Ray Swider, OASD C31 Space Systems and Dr. Trent Skidmore, Ohio University
Land Representative
Mr. Richard Barker, John E. Chance & Assoc. and Mr. Christopher Wilson, DaimlerChrysler
Marine Representative
Dr. Paul Galyean, Navcom Technology, Inc. and Mr. Frank Mullen, C.S. Draper Lab., Inc.

Pursuant to Article V of The Institute of Navigation’s bylaws, "additional Nominations may be made by petition, signed by at least 25 members entitled to vote for the office for which the candidate is nominated." All additional nominees must fulfill nomination requirements as indicated in the ION bylaws and the nomination must be received at The Institute of Navigation office by April 28, 2001.

Ballots will be mailed by April 30. Election results will be announced during Institute of Navigation 57th Annual Meeting being held June 11-13, 2001 in Albuquerque, New Mexico in conjunction with the CIGTF 20th Biennial Guidance Test Symposium. The newly elected ION officers will take office on June 13, 2001. Election results will be reported in the ION newsletter.

FROM THE ION PRESIDENT: ___________________ Exciting Times for Global Positioning Systems This continues to be a very exciting time for GPS! The GPS modernization effort is well underway with efforts to place the C/A code or R/C code on L2 with the first launch scheduled for 2003. Please refer to our newsletter article by Steve Lazar for more information on the replacement civil (R/C) code on L2. Civil signals will be placed on both L2 and L5 starting with the Block IIF satellites, with the first launch scheduled for 2005. The GPS III architecture study is underway to define GPS capabilities through 2030. The two selected contractor teams are headed by Boeing and Lockheed Martin, with Spectrum Astro participating on their own funding. These teams each have extensive outreach programs and are actively seeking input from the user community to help define the GPS III architecture, so I would encourage all of you to participate in this effort. The update to the GPS SPS Signal Specification is expected to be released this summer, reflecting the performance of GPS now that SA has been turned off. Also, the GPS vulnerability study performed for the Office of the Secretary of Transportation, expected to be released in the same time frame, may help determine what role other navigation systems will play in conjunction with GPS. There also has been much activity in Europe on Galileo with a decision on the future of this system expected soon. The interest in Galileo has led to increased European participation at ION conferences with new sessions to reflect this interest on interoperable use of GPS and Galileo to provide increased availability, integrity, and redundancy. Given the recent developments on the modernization of GPS, in addition to the GPS III and Galileo programs, the ION conferences continue to be very successful. The January National Technical meeting held in Long Beach, Calif. had close to 400 participants and featured a classified session sponsored by the GPS JPO at the Aerospace Corporation. The ION 57th Annual Meeting will be held in Albuquerque, New Mexico, June 11-13 and is being co-sponsored with CIGTF, which also will feature classified sessions, as well as the annual ION awards banquet. Close to 500 abstracts were received for the September ION GPS 2001 conference. More than half of the abstracts received from outside the United States, representing 29 countries, making it truly an international symposium. The new ION Web site is scheduled to be introduced in May, providing more services to ION members. These services include online membership renewal and the ability to search the ION site for proceedings papers and journal articles. Additional new content will feature a career section that will offer job listings and resume postings, an events calendar, and a consultants directory. I would like to welcome Rick Buongiovanni to the full-time staff of the ION. Rick is not new to the ION, and many of you probably know him for the audio visual support he provides at the ION conferences. Rick will be responsible for ION information systems, which will include Web page editing and support that will be especially helpful in conjunction with the upgrades to the ION Web site. Our ION Congressional Fellow, Phil Ward, has recently been selected by Senator Jim Inhofe (R-Okla.) to support Senate Armed Services policy issues in the Airland Forces Subcommittee, Strategic Forces Sub-committee, and the Readiness and Management Support Subcommittee with possible support to the Senate Select Committee on Intelligence. In Phil’s words, he will be working at "warp speed," but he is looking forward to this opportunity. For additional information, please refer to the article Phil has written for the newsletter. We are now soliciting nominations for the next ION Congressional Fellow. If you are interested, please submit an application to the ION National Office by June 1. I look forward to seeing you at our upcoming conferences!

The Purpose of The ION The Institute of Navigation, founded in 1945, is a non-profit professional society dedicated to the advancement of the art and science of navigation. It serves a diverse community including those interested in air, space, marine, land navigation and position determination. Although basically a national organization, its membership is worldwide, and it is affiliated with the International Association of the Institutes of Navigation. 2000-01 National Executive Committee President: Karen Van Dyke Executive Vice President: Ron Hatch Treasurer: Larry Hothem Eastern Region Vice President: Sally Frodge Central Region Vice President: Maj. John Raquet Western Region Vice President: Dr. A.J. Van Dierendonck Immediate Past President: Dr. Per Enge How to Reach The ION Telephone: 703-683-7101 Facsimile: 703-683-7105 Web site: http://www.ion.org E-Mail: membership@ion.org ION National Office Staff Director of Operations: Lisa Beaty Technical Director: Carl Andren Office Manager: Jennifer Murphy-Smith Assistant to the Technical Director: Miriam Lewis Meeting Services/Author Liaison: Connie Mayes Publication Department: Wendy Hickman Graphic Design & Layout: Paula Danko Information Systems: Rick Buongiovanni

From the ION Congressional Fellow: Finding a Place on the Hill
___________________

In my first report, I described my two-week Congressional Fellow orientation. In this report, I describe what has happened since. I believe my experiences will greatly benefit the next ION Congressional Fellow, and I will be here to help my fellow Fellow out in September of this year. I want to express my gratitude to Ken Holland for initiating the Congressional Fellowship program and to the ION Council for approving it. I am privileged to be the ION’s first Congressional Fellow. This is a wonderful opportunity to learn about the legislative process in the 107th Congress and to make a contribution. I am especially pleased to be a January start fellow rather than a September start as are most of the American Association for the Advancement of Science (AAAS) fellows.

On the afternoon of December 26, 2000, my wife, Nancy, and I drove away from our home in Dallas, Texas, where we lived since 1970. We arrived at our 2-bedroom apartment at 2:30 p.m. on December 29 braced for a Washington, D.C. snowstorm that, luckily, never materialized. We are settled into our new living quarters and we love it. Our apartment is less than two blocks from the Metro and has a lovely view of the Potomac River.

The AAAS helps you prepare a one-page curriculum vitae (CV) and a lot of previous Fellows tell you about their strategies and experiences during the interview process, but you are on your own to find your "place on the hill." I still have not found mine. My first choice is to be a special assistant in legislative areas requiring scientific and technical input for a member of Congress. This week, I also began pursuing a special assistant position on several permanent congressional committees. A third alternative is to work at the Library of Congress as a staff member of the Congressional Research Service. The interview process can take several days from the time you drop off your CV at a member’s front office until the cycle plays out. Usually, you start with the Legislative Director (LD), but sometimes the Chief of Staff (CoS) handles the first visit. Your goal is to eventually get an interview and to meet the CoS, and hopefully, the member. They are all very busy.

A Lot of Competition
Based on my experience, you have about one chance in five that the scheduler (a fancy name on the Hill for receptionist) will tell you that the LD is in. You follow up with phone calls, usually leaving voice mails, and send e-mails that are not returned. Somehow you finally reach someone, or even more exhilarating, your call is returned. Usually, the member already has a full staff and there is absolutely no more room. This is a little easier on the ego since one of the first things you make clear is that you have no financial impact on the member’s staffing budget! So you must proceed in parallel, not sequentially. I have kept eight CVs active at all times: four in the Senate and four in the House. I soon learned that there are numerous other organizations that sponsor Congressional Fellows. I spent a lot of time pursuing members who serve on the Senate or House Armed Services Committee only to discover that these members prefer to have high-ranking uniformed officers from the Department of Defense as Congressional Fellows on their staff. The AAAS did not cover the competition!

Fortunately, I have a strong interest in several other legislative policy areas that fit my professional and educational background. In the Senate, there is the Commerce, Science and Transportation Committee, especially the Aviation Subcommittee, and the Select Intelligence Committee. In the House, there is the Transportation and Infrastructure Committee, particularly the Aviation Subcommittee; the Science Committee, especially the Space and Aeronautics Subcommittee; and the Permanent Select Committee on Intelligence, particularly the Technical and Tactical Intelligence Subcommittee.

Identifying the members of these committees and subcommittees through the World Wide Web is simple and more information about the members is available at their own Web sites. The LD and CoS are usually not identified on the Web. This formed the basis of my prioritized list of interview candidates. The AAAS gave all the Fellows a booklet entitled "Congress At Your Fingertips" that provides this and many other details about Congress. Unfortunately, it describes the 106th Congress, but it is an excellent starting point. I am getting to know a lot of people on the hill and have no complaints about how I am being treated.

At the ION Council meeting in January, I passed on an observation based on my interactions during the AAAS orientation meetings that included several professional engineering organizations that sponsor Congressional Fellows. These organizations maintain offices in the Washington, D.C. area to influence science and technology legislation that benefits the advancement of their own field of engineering. Like the ION, their bylaws prevent them from becoming involved "politically." However, this means that they do not participate in the election process of the members of Congress. They do not consider their nonpartisan participation in promoting the use of "good science" in our country’s legislative process to benefit society as being "political." I suggest that the ION Council re-evaluate our bylaws from this same perspective and determine a course of action.

Since this article was written, Phil Ward has found his "place on the Hill" with Senator Jim Inhofe (R-Okla.). See From the ION President in this issue for details.

A White Paper: Replacement Code for Civil Use on L2
Steve Lazaar
___________________

The GPS Joint Program Office (GPS JPO) is investigating a number of options regarding the addition of a second general-purpose civil-signal at L2. This new civil signal was called for in the vice presidential announcement as an upgrade to GPS in addition to the new civil signal at L5. Although the announcement identified this signal as the C/A (course/acquisition) code, the addition of a new signal at L2 presents an opportunity to replace the C/A code bit sequence with another, modernized code with minimal impact to the space vehicle and future (upgraded) receivers. The rationale for adopting a replacement/civil (R/C) code in lieu of implementing C/A code and an assessment of its implications on existing and planned satellite programs are described below.

Recent C/A Code Findings
The C/A code was originally used primarily for rapid acquisition on a single frequency (L1- only) leading to P(Y) code track on L1 and L2. C/A code was designed to accommodate the needs of receivers using 1970s technology, that is performing a cold start with no or poor a priori time or position information, and uses a short (1 millisecond) 1,023-bit sequence. Today, the C/A code has become the mainstay of the civil (and international) uses of GPS and augmentations that have outgrown the original military use. Since the early 90s, spectrum management-oriented studies have indicated that, under certain limited circumstances, the short C/A sequences have a lower margin than previously thought for co-existing with other C/A codes. A C/A code co-channel self-interference model was developed that demonstrates how the short length of the code heightens cross-correlation effects and how this can result in loss of acquisition capability and positioning. At present, the instances of co-channel interference are infrequent and of short duration but may still impact users that require high availability and accuracy. Thus, C/A code limits the total number of GPS or augmentation signals that may simultaneously use the same frequency and makes the signal more vulnerable to additional interference. A new, longer code was developed for L5, the second civil signal for aviation, to overcome some of these limitations. This is not to say that current GPS C/A code users cannot meet the stringent requirements for safety-of-life use, just that current receiver technology permits use of a longer, more robust signal. The addition of a new signal on L2 provides an opportunity for its development.

R/C-Code and the Block IIR and IIF Programs
The Air Force GPS Joint Program Office has determined the estimated cost of implementing a range of options for incorporating R/C code in the Block IIR and IIF modernization programs. The options are listed below:

Option 1 generates a new, longer bit code sequence, instead of C/A code, on the new civil channel on L2. The new sequence is chipped at 1.023 MHz, which is the same bandwidth as the current C/A code. It also adds the option to select either C/A code, R/C code, or no modulation. This signal is modulated by the standard (ICD-GPS-200) navigation message.

Option 2 includes Option 1 and adds the option of turning off the navigation message on the civil channel on L2 independently of all other channels.

Option 3 includes Option 2 and adds an additional R/C code signal on L1 in addition to the existing C/A code.

Option 1 simply allows for the replacement of the C/A code on L2 with the R/C code. Option 2 adds to Option 1 the ability to transmit either the C/A code or R/C code on L2 without the navigation message modulation. This feature allows for more robust track of the signal and improves the resistance of the channel to interference. The lack of navigation message allows for longer integration time in the receiver and thereby reduces the tracking noise and potentially increases accuracy. Option 3 is significantly more complex than Options 1 and 2 since it generates a total of four signals on L1: C/A code, R/C code, P(Y) code and M code. At this time there are no active plans to pursue Option 3 further. For the other two options, no new code has been formally approved for the R/C code bit stream. A code has been identified for the purpose of determining the cost of the upgrade; namely, to use the L5 code sequences, albeit chipped at the C/A code rate. Initial analysis indicates that a longer code will improve cross correlation performance and thereby add some resistance to interference from external emitters or from large constellations of GPS satellites, augmentation satellites or other satellite navigation systems all sharing common frequencies.

Benefits and Risks of the R/C Code Option
The potential benefits of R/C code are:

• more robust civil signals for greater availability under interference,
• greater capacity for new (increased power) signals,
• competitive with potential future RNSS users in the band,
• option to restore or maintain current C/A-code and navigation message capability, and
• earlier opportunity (Block IIR) to test the performance of the L5 code on L2

The potential risks of R/C code are:

• additional testing required to validate noise improvement and acquisition performance,
• increased cost of modernization to the space and control segments (small increment expected),
• increased cost to future user equipment for adding extra code option (small increment expected), and
• minor impact to precise ionospheric measurement, due to dissimilar codes on L1 and L2 (i.e., C/A and R/C respectively).

Conclusion
GPS frequency sharing and interference studies indicate that there are limits to the future expansion of C/A code use. Moreover, current receiver technology can support more robust acquisition and ranging signal options. The addition of a new civil signal at L2 presents an opportunity to adopt a more robust civil signal design at relatively low marginal cost to the system. The code to be used on L5 has been identified as a promising candidate for the signal. It provides higher resistance to interference and greater capacity for adding additional signals on L2. The performance and potential risks and additional costs to the user segment for R/C code are being analyzed. Nevertheless, the anticipated changes to the Block IIR and IIF satellites would add the flexibility to broadcast either this new mode or to revert to a traditional C/A code for contingencies and testing.

Steve Lazar is with The Aerospace Corporation. He has spent the last 10 years advising the GPS Joint Program Office and the Federal Aviation Administration primarily on system architecture and spectrum management activities.

PORTNEY'S CORNER
___________________

Courtesy of Litton Guidance and Control Systems

It is 1878 and Ensign Albert Michelson, physics instructor at the U.S. Naval Academy, has his thoughts occupied with measuring the speed of light using an optical array of lenses, mirrors and fixtures. He will use the Naval Academy seawall as the path to conduct this experiment. He reflects back in history, reviewing earlier attempts that were used to measure the speed of light.

The earliest date that a close approximation of the speed of light could be obtained was 1675 when a Danish astronomer, Olaf Roemer, conducted observations of one of the moons of Jupiter by observing its eclipses by Jupiter. Roemer marked the times of the beginning of the eclipses (as the moon disappeared behind Jupiter’s disc). The moons revolve around Jupiter in almost the same plane containing the Earth and Jupiter, making the eclipses visible on Earth. In the previous century, Galileo discovered four of the Moons of Jupiter. Roemer, who believed that the speed of light was infinite, marked the times of successive eclipses of Io one of the four known moons (at that time) of Jupiter.

Roemer made many observations of these eclipses. He noted that as the Earth in its orbit increased its distance from Jupiter, the expected times of the eclipses increasingly lagged his predicted times. As the distance between Earth and Jupiter decreased, the times of the successive eclipses began to occur earlier. Figure 1 shows the relationship of the Earth to Jupiter at two diametrically opposed positions of the Earth in its orbit related to the corresponding positions of Jupiter (Jupiter’s orbital period is almost 12 years). Also shown is the moon Io of Jupiter as it begins to be eclipsed at these positions. Roemer calculated when the moon would appear after transiting Jupiter’s disc at the second position (based on an infinite speed of light) and found that Io emerged from its eclipse 22 minutes later than his calculation. He then confirmed that the speed of light was finite and that the later time of the emerging moon in the second position resulted from the additional amount of time that the light had to travel across the diameter of the Earth’s orbit. There are no records indicating that Roemer actually measured the speed of light (although he may have) at the time of this experiment.

What are the speeds of light measured by using (1) the mean diameter of the Earth’s orbit regarded as 172,000,000 statute miles in Roemer’s time and the 22 minutes later time than his prediction, (2) today’s accepted 185,800,000 statute miles for the Earth’s orbital mean diameter and the 22 minutes later time than his prediction, and (3) in what direction of the Earth’s displacement can the finite nature of the speed of light best be detected by observing successive eclipses of Io in its orbit around Jupiter?

A. 130,300 miles/sec; 185,900 miles/sec; when orthogonal to the line of sight
B. 130,300 miles/sec; 186,000 miles/sec; when almost parallel to the line of sight
C. 130,303 miles/sec; 140,758 miles/sec; when almost parallel to the line of sight
D. 138,000 miles/sec; 186,000 miles/sec; when orthogonal to the line of sight

Determining the speed of light using Roemer’s measurement of time to travel the length of the Earth’s orbital diameter (for his era) and today’s is shown below.

Roemer succeeded in discovering that the speed of light was finite but we find that his calculated time difference in observing the same eclipse at two diametrically opposed points in the Earth’s orbit (using today’s value of the diameter of Earth’s orbit) is greater by over 30% than today’s accepted value of 16.67 minutes which results in a reduced value for the speed of light. His precision was primarily hampered by the accuracy of his time source.

The Best Time to Measure
The best time to detect that the speed of light is finite is to observe two successive eclipses of the moon Io when the Earth’s day-to-day displacement in its orbit is virtually parallel to the line of sight to the observed eclipses for maximum displacement of the Earth’s position in its orbit during a period of the moon Io (42.5 hours).

The first terrestrial measurement of the velocity of light was accomplished by the French scientist Fizeau in 1849. The test apparatus employed a rotating tooth wheel as part of an array of lenses, a mirror and glass plate that produced a series of chopped light wave trains as depicted in Figure 2. Fizeau measured a value of 3.15 x 108 m/s for the velocity of light . Foucalt improved the test instrumentation and also showed that the velocity of light was slower in the medium of water than in air.

In 1878 Albert A. Michelson, on the faculty staff as a physics instructor at the U.S. Naval Academy, used a modified Foucalt method in measuring the most precise value of the velocity of light (186,508 mi/s) obtained at that time using this technique. He substituted a rotating mirror for the rotating tooth wheel and a flat plane mirror for a concave reflecting mirror and increased the optical path length almost fourfold. The improvements introduced by Michelson made the measurements obtained not only more objective but significantly more precise. His interest in measuring the speed of light began earlier at the U.S. Naval Academy as a student under Simon Newcomb, professor of physics. Newcomb, who later became a renowned astronomer at the U.S. Naval Observatory, was supported by a $5,000 congressional appropriation for an elaborate investigation of the velocity of light. Newcomb’s accuracy in his investigation was stunningly matched by then Ensign Albert Michelson conducting his own investigation with a ten dollar investment in instrumentation.

It is commonly thought that Michelson’s work in measuring the velocity of light, inventing the interferometer, continued improvement of his measurements of the velocity of light and his experiments with Morley on the effect of the ether drift on the propagation of light (negative results) led to his receiving the first Nobel prize awarded to an American scientist (physics) in 1907. In reality, it was Michelson’s work in the experimental determination of the length of the meter that led to his Nobel prize. The results of his ether drift experiment were used in Einstein’s 1905 paper on “Special Theory of Relativity.” In this paper Einstein emphasized that the velocity of light was constant, the same in all directions and independent of the motion of the source or the receiver. Michelson’s measurement of the speed of light continued to improve as seen in Figure 3 when in the late 1920s his eight sided rotating mirror was employed in an optical array and the light path length was extended to 22 miles between Mt. Wilson and Mt. San Antonio in Southern California.

Precision measurements of the velocity of light have continued to the present time using laser technology leading to today’s accepted value of 299,792.458 km/s or 186,282.397 mi/s in a vacuum. The rounded numbers used today for the velocity of light are 186,000 mi/s or 300,000 km/s.

Bibliography
Goldberg, Stanley and Roger H. Stuewer. The Michelson Era in American Science 1870-1930. New York: American Institute of Physics, 1988
Jaffe, Bernard. Michelson and the Speed of Light. Garden City, New York: Anchor Books DoubleDay & Company, Inc., 1960
Livingston, Dorothy Michelson. The Master of the Light. New York: Charles Scribner’s & Sons, 1973
Logsdon, Tom. Orbital Mechanics. New York: John Wiley & Sons, Inc.1998 Parker, Sybil P. Concise Encyclopedia of Science & Technology. New York: McGraw-Hill, Inc., 1992
Sears, Francis Weston and Mark W. Zemansky. University Physics. Reading, MA: Addison-Wesley Publishing Company, Inc. 1957
St. John’s Staff. Optics (laboratory text). Annapolis, Md. St. John’s College, 1984.

NTM 2001: Look at the Changing Landscape of Navigation Technology
___________________

More than 100 technical papers were presented during three days of parallel-track sessions at the ION’s National Technical Meeting held at the Westin Hotel in Long Beach, Calif., January 22-24. The meeting featured a well-attended classified session at The Aerospace Corporation. About 400 persons attended the National Technical Meeting, which was highlighted once again by the quality of the papers delivered. Maj. John Raquet, U.S. Air Force, served as general chair, and Dr. Pratap Misra, MIT Lincoln Laboratory, was program chair.

Many Thanks to Our Exhibitors!
AG Davis Gage & Engineering; AIAA; Allen Oborne Associates, Inc.; American GNC Corporation; Applanix Corporation; Cast; Center for Remote Sensing, Inc.; GPS World Magazine; Interstate Electronics Corp.; Litton Systems, Inc.; Raytheon Systems Co.; TChip Semiconductor SA; The Boeing Company; and 746th TS/TGGP.

Galileo Moves Ahead?
___________________

"Galileo can give us better service and opportunities to use satellite navigation in many new areas" - Bjorn Rosengren, Chairman of the Council of Transport On April 5, the European Union transport ministers approved arrangements for continued work on the development of the Galileo satellite navigation system. The decision is based on an action plan drawn up by the Swedish presidency. According to the plan, the focus is now on defining how the business sector can participate in financing the project and how the project is to be organized. A further decision will be taken by the EU in December. "Europe now has the opportunity to build a modern, civil navigation system that may be an important element in the European and global infrastructure" said Bjorn Rosengren, chairman of the Council of Transport.

ION is Recruiting For A 2002 Congressional Fellow
___________________

	For more information and/or for an application packet, go to www.ion.org, or call the ION headquarters at (703) 683-7101, or write to: Institute of Navigation Congressional Fellowship Program Attn: Carl Andren 1800 Diagonal Road, Suite 480 Alexandria, VA 22314 E-mail: candren@ion.org Qualifications ION Membership (Four or More Years) U.S. Citizenship Navigation or Engineering Experience

Navigation and Navigation and Sociology
One of a Series of Columns By ION Historian Marvin May
___________________

Unlike those of us who ply our trade in the field of navigation that are ambivalent as to whether navigation is an art or a science, sociologists are assertive that their profession is a science. Although one may not subscribe to the theory that engineers and scientists are social human beings, sociologists have attempted to establish the causal relationships governing the inventions of devices and processes that technology has produced. Navigation is historically defined as "the art or science of directing a craft to a position." Sociology is defined as "the science of human society and of social relations." Combining the two definitions, the navigation sociologist tries to determine answers to such questions as these: "Why do people choose to move?" "Where do they move to?" "How do they choose the crafts they move in?" "Why do they need to know where they are?" "How accurately do they need to know where they are?" "What tradeoffs are made in choosing their navigation devices?" "What are the social processes that drive the direction of navigation system development?" "How does society pay for and why does it benefit from navigation technology?"

In his book Inventing Accuracy, Donald MacKenzie delves into the history of the dominant technology of missile guidance: inertial, or "black box" navigation. It provides insight into the driving forces for the development of inertial navigation by describing the interactions among the technological challenges, the political strategies, and the societal needs. MacKenzie intersperses detailed technical descriptions of inertial sensor and system innovations with the search for rationales in the historical and sociological domains.

"Black Box" Instrumentation
The book is threaded with a chronological accounting of "black box" instrumentation beginning in the 1850s with the father of "gyro culture" French physicist Leon Foucault.

It then proceeds to the implementations of the practical gyrocompass by Anschutz and Sperry, developments that were contemporaneous with Albert Einstein’s relativity formulations. Inertial navigation’s history remained closely intertwined with Einstein’s writings - both technically as gravitational effects being a limiting factor and ethically as nuclear weaponry being a principle application.

Theoretical and electromechanical advances in Europe and Russia in the 1920s and 1930s led to the extensive use of inertial sensors in the German V-2 ballistic missile, a system that achieved infamy beyond that of almost any military technology of the period except the atomic bomb. Although the V-2 had debatable military effectiveness and did not fully implement inertial navigation, its knowledge base on ballistic missile guidance with inertial instrumentation was passed on to the Soviet Union and the United States. Within the post-World War II burgeoning U.S. economy, flourished the pioneering efforts of M.I.T. Instrumentation Laboratory (subsequently renamed the Charles Stark Draper Laboratory), the Autonetics Division of North American Aviation, and Northrop Corporation.

In addition to chronicling the formidable technological challenges conquered by these organizations, characteristics of the charismatic personalities of leaders such as Draper and John Slater of Autonetics are treated as critical ingredients to the overall successful recipes. By around 1950, the black-box navigation work at Autonetics and the Instrumentation Laboratory resulted, respectively, in the XN series of inertial navigators for the Navaho missile and the FEBE (after the sun God, Pheobus) stellar inertial bomber navigation system. MacKenzie emphasizes that the creation of the new technology of inertial navigation cannot be captured by the traditional notion of invention, with its single crucial "eureka moment." Rather, it is described as a triumph of "heterogeneous engineering" encompassing the accomplishments of a vast number of individuals and organizations. The author documents the technological trajectory of improved inertial sensor accuracy describing in detail the intensive, continuous refinements in precision machining, dimensional stability of materials, calibration, and test techniques that led to the third generation performance of the Air Force’s Minutemen 3 and the Navy’s Trident I guidance systems of the late 1970s. The MX’s guidance system, referred to with the metaphor of a beryllium baby, and the Trident I’s submarine’s navigation subsystem anchored by the incredible stability of the electrostatic gyro, still represent the pinnacle in inertial guidance accuracy.

The Future of Inertial Sensors
MacKenzie speculates about the future of inertial sensors emphasizing that historically there was no clear pattern of driving forces, but rather a subtle combination of political, social, and technological nuances that evolved into accuracy reductions of five orders of magnitude. The author’s case for attributing the evolution to a seemingly random and complex combination of factors is supported by the varied approaches and techniques employed by the United States Navy, Air Force, and their counterparts in the Soviet Union. Ultimately and somewhat predictably, the book concludes with a sociological flavor, contemplating whether mankind (the author observes that women were remarkably absent from the culture of inertial guidance) will abandon focusing the utilization of these systems to nuclear weapons of mass destruction.

Johannes Kepler Award Nominations Requested
___________________

Nominations are being accepted for the Johannes Kepler Award. The purpose of the award is to honor an individual for sustained and significant contributions to the development of satellite navigation. All members of the ION are eligible.

To submit a nomination, go to www.ion.org/awards.html, click on Kepler Awards, complete the form and submit. Or, send a supporting letter via fax (703-683-7105) or post by Aug. 1, 2001.:
Satellite Division Awards Chair
ION
1800 Diagonal Road, Suite 480
Alexandria, VA 22314

In Memorial
___________________

James J. Kramer, 71, the Institute of Navigation’s executive director in 1990 and a retired associate administrator for technology for the National Aeronautics and Space Administration who also managed advanced aircraft research programs for the General Electric Co., died Jan. 4 at the Washington Home. He had Alzheimer’s disease.

Dr. Kramer directed NASA’s research in aeronautics, space technology, and energy in the late 1970s. Among his programs were projects to increase aircraft energy efficiency and creation of systems for transmitting data from spacecrafts.

After retiring from NASA in 1979, Dr. Kramer managed planning and development and advanced technology programs for GE’s aircraft engines division. He chaired a technology group for the Radio and Technical Commission for Aeronautics, which examines air traffic management systems, and the Aeronautics and Space Engineering Board of the National Academy of Engineering, which advises NASA.

Cdre Alfonse Sadek, 73, president of the Arab Institute of Navigation, founding member and former president of the International Association of Institutes of Navigation (IAIN) died of a stroke on Dec. 7, 2000. His death is a great loss to the navigational world. Sadek dedicated himself to many scientific, cultural and social issues. As a mark of respect and to commemorate him, the IAIN has agreed that the best paper award at an IAIN meeting will be known as the "Sadek Award."

Two ION Past Presidents Retire This Year
___________________

Ken Holland (pictured) ION President ‘93–‘94 and current ION meetings chair, retired in January after serving 30 years with the U.S. Air Force. He had been serving since 1993 as the 46th Test Group Technical Director. Ken Seidelmann (ION President ‘79–‘80 and ION Fellow) retired in October after 35 years of service at the U.S. Naval Observatory. His last position was as director of Astrometry. Seidelmann is residing in Charlottesville, Virginia.

Another Block IIR Launched
___________________

CAPE CANAVERAL, Fla., Jan. 30, 2001. A Boeing Delta II rocket fired up the night sky to launch a Global Positioning System navigational satellite into space. Liftoff occurred at 2:55 a.m. EST. Twenty-five minutes later, the satellite was placed into an elliptical orbit almost 11,000 miles above the Earth.

Coast Guard Cautions On WAAS Maritime Use
___________________

In response to the Federal Aviation Administration (FAA) announcement on August 24, 2000 that the Wide Area Augmentation System (WAAS) was now available "for use by some aviation and all non-aviation uses," the U.S. Coast Guard warned that WAAS is still under development and should not be relied upon for safety-critical maritime navigation. The Coast Guard did note that WAAS could be used under certain circumstances for "increasing situational awareness." This is the same view that the FAA has adopted for the aviation community. The FAA announcement had further stated that "WAAS continues to be developed to provide the necessary integrity for the WAAS-required, safety-critical applications" [and] "until the system design is completed and initial operational capability is declared, it is not an approved source of aircraft navigation under Instrument Flight Rules (IFR)."

The Coast Guard points out that the Maritime Differential Global Positioning System (DGPS) Service remains fully operational and continues to notify users within six seconds of any GPS satellite or DGPS corrections that are out of tolerance. This service has been adopted as a maritime standard in over 36 countries.

As always, the Coast Guard strongly encouraged mariners to use all available means of navigation and not rely on any single system. Once WAAS also becomes fully operational, the combination of Coast Guard and FAA systems are expected to provide a robust, complementary service to all modes of transportation.

Questions regarding this issue can be directed to the USCG Navigation Center, (703) 313-5900 or at http://www.navcen.uscg.mil/.

News in Brief
___________________

Two Rockwell Collins Engineers Honored
John T. Kelly was named one of Rockwell Collins’ Engineers of the Year. Kelly is a senior systems engineer in the Government Systems business unit in Cedar Rapids. The award, presented during National Engineering Week, February 18-24, 2001, is Rockwell’s highest honor recognizing engineering achievements within the company. Kelly is recognized for his contributions in technical innovations - such as applying GPS to survey, gun laying, wireless network systems, and targeting markets. Kelly earned his bachelor’s degree in electronic engineering from California Polytechnic in 1987 and his master’s degree in systems engineering from Iowa State University in 1999. He has worked for Rockwell Collins since 1994.

Donald (Alex) Stratton from Rockwell Collins’ Air Transport Systems was also recognized for his commercial aviation work in Global Navigation Satellite Systems avionics design, analysis, integration and testing, industry leadership, and intellectual property development.

What's That Up in the Sky?
Watch for strange objects flying around in the skies over Las Cruces, New Mexico! Physical Science Laboratory, under contract to the National Aeronautics and Space Administration to serve as the flight-test arm of the Environmental Research Aircraft and Sensor Technology HALE Remotely Operated Aircraft Program, is involved in an exciting new initiative focused on unmanned aerial vehicles (UAVs). The UAV program involves research, analysis, and validation resulting in Federal Aviation Administration regulations for certification and operation of UAVs in U.S. civil airspace. This initiative can be a critical impetus in keeping the United States at the forefront of aviation and the UAV industry. Part of the initiative is the development of a long-range UAV flight test corridor for certification and validation of UAVs and their subsystems. The corridor will comprise a triangular track of approximately 9,000 miles linking New Mexico, Hawaii, and Alaska, providing a wide diversity of routes and operating environments for safe flight operations above normal air traffic. Flight experiment design and operations support will be conducted at the Las Cruces International Airport and other locations.

SECTION NEWS _______________________________________________ THE ROCKY MOUNTAIN SECTION of the Institute of Navigation held its annual dinner meeting on Thursday, January 25, 2001, at the Air Force Academy Officer’s Club in Colorado Springs, Colo. Fifteen people attended. ION Western Regional Vice-President, Dr. A.J. Van Dierendonck, was the guest speaker. He gave a talk entitled, "Future GPS Civil Signals," in which he discussed the details both of the new GPS L5 signal and the new CA signal on L2. At the meeting, elections were held for the offices of chair and treasurer. Richard Pache was elected chair. Pache has been an active member of RMS-ION for four years and presently works in the GPS hardware group at Schriever AFB for Allied Signal/ Honeywell. Second Lt. Stephen Bolt was elected treasurer. Bolt is a GPS Block IIR navigation payload specialist in the Second Space Operations Squadron at Schriever AFB. The Rocky Mountain Section extends its congratulations to its new officers. DAYTON SECTION. The Dayton Section met March 8 at the Wright-Patterson O’Club. Capt. Paul Henderson, a graduate student at the Air Force Institute of Technology, spoke on the "Development and Testing of a Multiple Filter Approach for Precise DGPS Positioning and Carrier-Phase Ambiguity Resolution." The presentation covered his use of a multiple model Kalman filter to resolve the carrier-phase integer ambiguities inherent in the solution of Differential GPS SOUTHERN CALIFORNIA SECTION. The section held a luncheon meeting on Monday, March 12 that was sponsored and hosted by the Aerospace Corporation. The guest speaker, Kanwar Chadha, founder and vice-president of marketing at SiRF Technology, discussed "GPS as a Location Function in Consumer Mobile Platforms: Challenges and Opportunities". Also, the Southern California Section will be holding elections in June. Volunteers for the nominating committee are being accepted now. To volunteer, contact Cecelia Chodorow at (310) 607-6651 or send e-mail to cmchodorow@west.raytheon.com. GREATER PHILADELPHIA SECTION. The Greater Philadelphia Section, with the assistance of the ION National Office, completed an inventory and access system for its navigation library at the PSU/ARL’s facility in Warminster, Pa. The library has an extensive collection of navigation books and periodicals including a complete set of ION journals. For further information, contact Marvin May, chief scientist, Navigation Research and Development Center, Warminster, Pa. 18974. Phone: (215) 682-4003; Fax: (215) 682-4023 (fax); www.arl.psu.edu/facilities/facilities.html. NEW ENGLAND SECTION. On January 17, the New England Section had its 17th Meeting at the Volpe National Transportation Systems Center in Cambridge, Mass. Presentations on "Recognizing Context via Wearable Sensors," and "Inertial Gesture Recognition with Compact IMUs" were given by Brian Clarkson and Ari Benbasat, respectively, both of the MIT Media Laboratory. On February 28, the section held an away meeting at the Haystack Observatory in Westford, Mass. The meeting consisted of lectures by Mr. Dennis Hall, Dr. Joe Salah, Dr. Fred Rosenberg, Dr. Phil Erickson, and Mr. Phil Shute and a tour guided by Mr. Hall. The tour provided an opportunity to see this unique facility and meet some of its key engineers and scientists. The Haystack Observatory is an inter-disciplinary research center engaged in radio astronomy, geodesy, atmospheric sciences, and radar applications. In conjunction with the R&D Center’s open house, on March 20 the section held its 19th meeting at the U.S. Coast Guard Research and Development Center. Projects of specific navigation interests were on display during the open house, including maritime Automatic Identification Systems and the Optics Laboratory for navigation light measurements (light tunnel).

Corporate Profile ______________ Volpe National Transportation Systems Center www.volpe.dot.gov The DOT’s John A. Volpe National Transportation Systems Center in Cambridge, Massachusetts, is an internationally recognized center of transportation and logistics expertise. Through research and development, engineering and analysis, the Volpe Center helps decisionmakers define problems and pursue solutions to lead transportation into the 21st century. In essence, the Volpe Center is a catalyst for innovation - a source of critical insight necessary to realize transportation’s promising future. The Volpe Center’s work includes a broad mix of projects that cut across traditional transportation modes and technical disciplines. It is well known internationally for its transportation expertise. The Volpe Center’s highly skilled staff of experts is respected for their comprehensive knowledge and understanding of the transportation system. The center has also successfully implemented several major programs such as the Federal Aviation Administration’s Enhanced Traffic Management System (ETMS) and Safety Performance Analysis System (SPAS), and the Federal Motor Carrier Safety Administration’s SafeStat Online. The Center assists federal, state, and local governments, industry and academia in a number of areas, including human factors research, system design, implementation, and assessment, global tracking, strategic investment and resource allocation, environmental preservation, and organizational effectiveness. In these and other areas, the center provides its clients with valued policy support and strategic planning and analysis. The Volpe Center is part of the U.S. Department of Transportation’s Research and Special Programs Administration. However, the center differs from most federal organizations in that it receives no direct appropriation from Congress. Instead, it is funded 100 percent through a fee-for-service structure in which all of its costs are covered by sponsored project work. The Volpe Center supports approximately $200 million annually in project work.

New Corporate Members _____________________ The ION extends a warm welcome to the following new Corporate Members: The University of Texas U.S. DOT/Volpe National Transportation System Center U.S. Merchant Marine Academy Kongsberg Seatex AS

CALENDAR ________________ MAY 2001 8-11: GNSS 2001 5th European Symposium on Global Navigation Satellite Systems Palacio de Congresos de Sevilla, Seville, Spain Contact: Ms. Pilar Prieto Phone: +34-91-3210206 Fax: +34-91-3213169 e-mail: pprieto@aena.es or GNSS.2001@aena.es 13-18: RTCM Annual Assembly Meeting; Trade Winds Hotel, St. Petersburg, FL Contact: W.T. Adams, RTCM Tel: 703-684-4481 Fax: 703-836-4229 JUNE 2001 5-8: KIS 2001 International Symposium on Kinematic Systems in Geodesy, Geomatics and Navigation; Banff Centre, Banff, Canada Contact: Dr. Gérard Lachapelle or Dr. M. Elizabeth Cannon Tel: 403-220-5834 Fax: 403-284-1980 Web Site: www.geomatics.ucalgary.ca/KIS2001 11-13: 57th ION Annual Meeting and the CIGTF 20th Biennial Guidance Test Symposium; Albuquerque, New Mexico Contact: ION Tel: 703-683-7101 Fax: 703-683-7105 Web Site: www.ion.org/meetings.html SEPTEMBER 2001 11-14: ION GPS 2001; Salt Lake City, Utah Contact: ION Tel: 703-683-7101 Fax: 703-683-7105 Web Site: www.ion.org

_____________________________________________________________________________________________

Close Window / Return to ION Website