The table of contents for our website has been updated so that it lists all posts and provides a correct link to each. See http://www.hughesscgheritage.com/table-of-contents/
In 2003, when Boeing was collaborating with JPL on a probe proposal, it occurred to me that a brochure should be developed for the upcoming 2ndInternational Planetary Probe Workshop at NASA Ames. I convinced Boeing management of the merit of this concept and began working with Jim Santoni, our resident graphics guru. We reviewed the archives of the Pioneer Venus and Galileo programs to find the photos that would most convincingly send the message that we had the experience needed to design planetary entry probes for future NASA missions.
One photo caught my eye. It captured our skilled technicians deep in the final assembly of the Galileo probe. They were carefully positioning the aft cover on the descent vehicle installed in the deceleration module. There was only one problem with the photo: the technicians were touching extremely valuable hardware with their bare hands. One was even wearing a ring. Knowing this 1980’s practice was certainly not consistent with the rules enforced in the early 2000s, I asked Jim to retouch the photo. For the brochure, he graphically applied gloves to the technicians’ hands. The cover of the brochure is included below, with the blue-gloved hands of the technicians clearly visible.
Several years later, as I was chatting with a young engineer about my experiences on the Pioneer Venus and the Galileo probes, he mentioned that he had seen the original photo of technicians. He recalled that the photo captured the technicians working without gloves. There I was, caught blue-handed as I explained how we had retouched the original photo for the brochure.
Richard ‘Dick’ Switz was born on May 18, 1928 in a farmhouse in Switz City, Indiana, son of Henry ‘Bud’ and Lucille Switz with older brother Donald and younger brother Hal. Switz City was named for his great grandfather. He grew up working on the family farm and attended Switz City High School.
Dick graduated from Purdue University, for which he maintained lifelong affection and pride, earning a Bachelor of Science in Civil Engineering. He was drafted after graduation into the U.S. Army, serving two years assigned to the Corps of Engineers in the Pentagon. After his discharge from the Army Dick accepted a job with Ryan Aircraft, and relocated to sunny San Diego, beginning the California adventure lasting the rest of his life. He enjoyed music, photography, traveling, time with family and friends and adored his grand/great-grandkids.
Dick spent most of his career with Hughes Aircraft, moving to El Segundo in 1966 from Reseda and played a key roles in designing Surveyor—the first spacecraft to successfully soft land on the Moon—many communication satellites and exploring other planets with Pioneer Venus and Galileo. After retiring in the mid-80s as Chief Scientist, Dick was elected for four years to the El Segundo City Council to proudly serve his hometown and was a parishioner of St. Anthony’s for over 50 years.
Dick passed away peacefully on October 14 at Torrance Memorial Hospital surrounded by family. He is survived by children Jim Switz and Rita Nelson (both of WA State) and Lauren Harger in Manhattan Beach, grandchildren Laura, Jenna, Sean and Megan and great-grandchildren Linken and Olia.
Visitation will be from 5 to 9pm on October 22 at the Rice Mortuary at 5310 Torrance Blvd in Torrance. A service will be held on October 23 at American Martyrs Catholic Church located at 624 15thStreet in Manhattan Beach at 10am followed by a reception at 11am.
Bob Varga, a longtime friend, passed away on October 2 as a result of complications from food poisoning. Bob spent many years at Hughes Aircraft and contributed greatly to a variety of proposals and spacecraft programs. Services and interment will be at the Green Hills Memorial Park at 11:30 am on October 17. Green Hills is located at 27501 South Western Avenue in Rancho Palos Verdes. Further information can be found at the Green Hills website–https://greenhillsmemorial.com/
Some time ago, perhaps several years, Maggy Murray, Bill’s wife, contacted me and volunteered some of Bill’s mementos for our website. Included were photographs of a number of launches of Hughes satellites. Unfortunately, these photos did not have a caption that identified the satellites being launched. I filed these away and forgot them until recently. Looking at the photos I realized that the launch vehicles were numbered and that would allow identification of the Hughes satellite being launched.
I found a website, KevinForsyth.net, that listed all the numbered Delta launches that allowed identification of the Hughes satellites. I also learned that the Delta is no longer in production and the last launch was on September 15, 2018 for a NASA mission, ICESAT-2. There were a total of 381 Delta launches with only 16 failures, a reliability of almost 96%.
Information on Centaur launches can be found on Gunter’s Space Page.
Delta B Syncom II launch July 26, 1963
Delta D Syncom III launch August 19, 1964
Delta D Earlybird on Launch Pad April 1965
Delta D Earlybird Launch April 6, 1965
Delta E1 Intelsat II F1 launch October 26, 1966
Atlas Centaur AC35 Intelsat IV F1 launch May 22, 1975
The Pioneer Venus Orbiter incorporated a payload of 12 scientific instruments one of which was a fluxgate magnetometer provided by Chris Russell of UCLA, the principal investigator. Previous flybys of Venus had revealed that the magnetic field of Venus was much weaker than Earth’s. The resulting system requirements for the Orbiter magnetic fields are shown in Figure 4-2 in Reference 1. The most challenging requirement is that the remnant field at the magnetometer (after a 50-gauss demagnetization of the spacecraft) be 0.5 gamma or less. A Gauss is the usual measure used in magnetics—a gamma is 0.00001 Gauss. The earth’s surface magnetic field varies from 0.3 to 0.6 Gauss.
These requirements presented some issues that Hughes had not dealt with previously. At the beginning of the PV program no one at Hughes that I knew had experience in this area. Very fortuitously at this time we received an application from a TRW engineer, Chris Thorpe, who had performed these tasks for the TRW Pioneer spacecraft and had worked with Chris Russell previously. We hired him very quickly into the Perry Ackerman lab and assigned him to PV program. Chris was a delightful Englishman with a wry sense of humor and supported me in systems engineering and Tony Lauletta in science integration throughout the program.
Chris quickly demonstrated his knowledge of spacecraft magnetics and instituted a magnetic control program that included:
- Formulating and maintaining a magnetic model of the Orbiter that predicted the magnetic field at the magnetometer
- Limiting the type and amount of magnetic materials used in fabrication.
- Using a nonmagnetic electroless nickel plate
- Controlling the location and orientation of magnetically troublesome units on the equipment shelf.
- Separating the magnetometer from the spacecraft by a deployable boom
- Provide for magnetic compensation of units that utilize permanent magnets in their operation to reduce their field contribution at the magnetometer
Based on Chris’ calculations the boom length was set at 15 ft 6 in. (4.72 meters). As I recall Chris’s prediction was 14.5 feet and one foot was added to provide some margin. Chris maintained the magnetic model throughout the Orbiter development.
The boom, consisting of three hinged segments, is folded together and stowed on the orbiter shelf until deployed shortly after launch. The boom is secured by two redundant pyrotechnic pinpullers either of which when fired would release the boom for deployment. As the three segments extend, each hinged joint locks in the deployed position. A spin rate of 6.5 rpm provides the centrifugal force that ensures deployment and positive latching.
System level testing of the magnetometer boom proved to be problematic. The boom root hinge, when pyrotechnically released, was to deploy with the spacecraft spinning at 6.5 rpm. However, aerodynamic drag prevented the boom from fully extending in sea level density air. In order to validate the design it was necessary to encapsulate the spacecraft in a large plastic tent filled with 90% helium that provide a gas mixture with one fifth the density of air. The deployment test in this environment was successful.
Two system level magnetic tests are required—remanent and stray field determination. The remanent test is to determine the magnetic field of the quiescent spacecraft and requires a magnetic coil to cancel the earth’s magnetic field. The NASA Ames facility Magnetic Standards Laboratory and Test Facility in Mountain View, CA was used for this test and of course this required shipping the spacecraft to that facility. Tests were conducted with the spacecraft in a magnetized and demagnetized state. The stray field test to determine the magnetic field of the operating spacecraft was conducted in the Hughes high bay in the early morning to provide a magnetically quiet environment. The test results are presented in Figure 4.2 in from Reference 1. Chris Thorpe oversaw these tests.
According to Chris Russell: The most definitive measurements of the magnetic moment of Venus were obtained during the Pioneer Venus Orbiter mission in its first years of operation (1979-1981). Repeated low-altitude (~ 150 km) passes by that spacecraft over the antisolar region, coupled with dayside observations to the same altitude, proved the insignificance of a field of internal origin in near-Venus space. The observed fields for the most part could be explained as solar wind interaction-induced features. The new upper limit on the dipole moment obtained from the Pioneer Venus Orbiter wake measurements placed the Venus intrinsic magnetic field at ~ 10-5 times that of Earth.
At the conclusion of the Pioneer Venus program Chris and I were assigned to the newly started Galileo probe effort. After I left Galileo I lost track of Chris. Recently I learned that he passed away in 2000 at the age of 76. If someone can provide any biographical details for Chris I can add them to this post.
Reference 1. Pioneer Venus Final Report, Contract No. NAS 2-8300, December 1978, Bernard J. Bienstock.
The two Pioneer Venus spacecraft were designed to be launched by the Atlas-Centaur for the 1978 Venus opportunity. Earlier studies had considered the Thor-Delta launch vehicle, but the Atlas-Centaur was judged by NASA to provide superior science performance and potential cost savings due to the greater payload capability. The starting point for spacecraft design is the allowable mass for the two spacecraft that is determined by the performance of the designated launch vehicle. Our customer, NASA’s Ames Research Center, adopted a specification weight for us to work to allowing for a cushion or contingency below the Atlas-Centaur launch capability. The ARC specification values, as a function of time, are shown in Figures 4-1 and 4-2 for the Orbiter and Multiprobe spacecrafts.
The 1978 Venus launch opportunity can be divided into two phases. The earlier launch opportunity, late May-early June, has a greater flight time to Venus and is a Type II interplanetary trajectory traversing an arc of more than 180O about the sun. However, this launch requires greater launch vehicle performance and provide less payload capability. The later launches in August, use a Type I interplanetary trajectory (less than 180O solar arc) and provide more than a 50% greater payload capability. As neither Hughes nor NASA Ames could support two simultaneous launch campaigns the Orbiter and Multiprobe require using both the early and late launch opportunities for the 1978 Venus opportunity. The Orbiter weight was significantly less than the Multiprobe and could launched during the earlier opportunity. An advantage is the 60% lower ∆V required for orbit insertion at Venus. The August launch opportunity is then available for the 60% heavier Multiprobe.
The final mass properties measurements for the two spacecraft are shown in Table 4-1 from the Reference 1. Note that the first row in the Table which is labeled “Spacecraft height” should read “Spacecraft weight.” Both spacecraft are stable spinners based upon the HS-333 design.
Joe Lotta was responsible for the Pioneer Venus mass properties analyses. This involved collecting inputs from each design area on a monthly basis and calculating the overall mass properties for each spacecraft. As shown in Figures 4-1 and 4-2 from Reference 1, over the course of the nearly four-year program weight growth was a constant concern. Considerable effort was devoted to trying to control weight growth and finding weight savings. At every opportunity trade-offs were considered and lists of weight savings with the cost detailed for each saving would be considered. Those weight savings characterized by lower dollars per pound would be implemented. Reference 1 documents 90 pounds of savings implemented for the Orbiter and 105 pounds for the Multiprobe. NASA ARC was able to provide increases in their specification weights to accommodate our weight growth. Some must have been due to Atlas Centaur performance improvements and the rest due to reduced contingencies and weight reserves. In retrospect it all came together and we witnessed two very successful missions.
Reference 1. Pioneer Venus Final Project Report. HS507-7970. December 1978, Bernard J. Bienstock.
The attached IDC, by Steve Dorfman, outlines for the Pioneer Venus team award fee based upon NASA’s evaluation of Hughes performance. Note that Tables 3 and 4 are missing and Table 7 is not mentioned in the text.
The attached letter, dated 27 August, 1979, from Dr. Wheelon to C. A. Syvertson, director of NASA’s Ames Research Center, analyzes the cost growth in Hughes’ Pioneer Venus program. The contract was cost plus award fee and what was at stake here was the determination by the Ames Performance Evaluation Board of Hughes’ award fee. This analysis was undertaken at the invitation of Ames to provide the causes for the program cost growth.
The following comments have been added by Steve Dorfman:
Jerry presented this paper presented at the 50th International Astronautical Congress, 4 – 8 October 1999, Amsterdam, Netherlands see www.iafastro.org. It details the recovery operations, led by Jerry, for the Hughes HGS-1 satellite that was launched for Asia Satellite Communications Ltd. Our search of the International Astronautical Foundation (IAF) online archives reveals that this paper or any reference to it is not available. The IAF indicates that no papers prior to 2004 are available. We feel that researchers should have online access to this paper as it is the definitive reference for this recovery mission.
Many wonderful and talented people at Hughes contributed to the success of this mission. A tribute to many of them as well as other contributors around the world is illustrated in the official mission poster which bears the signatures of all those folks.