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History of the Delta Launch Vehicle



Current Delta News

(What about Delta IV?)
04-Oct-02 | NAVSTAR delays

Over the past year or more, NAVSTAR launches have been continually pushed into the future, primarily because the GPS constellation is healthy and not in need of any more spares, but also due to safety-related upgrades to the Delta II self-destruct system. If NAVSTAR IIR-8 and NASA’s ICESAT/CHIPSat both manage to launch this year, it will bring the grand total of 2002 Delta II launches to 5, the slowest year since 1994-1995, a two-year drought of only 3 launches per year. It may be mere coincidence, but the quiet schedule has proved convenient for Boeing, which has conscripted much of the Delta team into preparations for the first flight of the new Delta IV.

28-Aug-02 | Hope fades for NASA’s CONTOUR mission.

On 15 August CONTOUR was due to fire its on-board solid motor to leave Earth orbit, but since that time no signals from the spacecraft have been received. Adding to the concern is a 16 August telescope observation that appears to show two objects along CONTOUR’s intended trajectory, possibly a sign of catastrophic failure. (A third, smaller object has since been spotted.) One drawback to tracking efforts is the fact that at the time of ignition, the Deep Space Network (DSN) was unable to track the spacecraft due to its low altitude (about 120 nm); to this author this was a major flaw in the mission design. Operators have stepped down from the emergency nearly-continuous monitoring mode to free up the DSN for other missions. Communications attempts will now be made about once a week, and a concerted last-ditch attempt to communicate will be made in early December. Meanwhile, an investigation team has been formed, to be led by newly-appointed NASA Chief Engineer Theron M. Bradley Jr, a former nuclear engineer for the U.S. Navy. (NASA Press Release, 26-Aug-02)

22-Jul-02 | 30 years of Landsat

Tuesday, 23 July, marks the 30th anniversary of the launch of the first Earth Resources Technology Satellite, better known as Landsat-1. The Delta 0900 vehicle that launched it was the first to use the four-digit designator; more importantly, it was also the first to use 9 solid booster motors, and the first flight of the Delta Inertial Guidance System (DIGS). Initially considered an experimental satellite, Landsat-1 and its successors were so successful that today the program is referred to as “the central pillar of the national remote sensing capability.” (NASA Press Release, 22-Jul-02)

17-Jul-02 | Genesis’s unique flight path

The Genesis mission to collect samples of the solar wind and return them to Earth has a unique, propellant-conserving orbit made possible by complex, esoteric, applied mathematics and chaos theory. Here’s a NASA Press Release (17-Jul-02, revised 24-Jul-02), and an interview with the software developer, Martin Lo.

09-Jul-02 | Delta flight 292 – CONTOUR

Delta flight 292 has successfully launched CONTOUR, NASA’s Comet Nucleus Tour probe. Even as thunderstorms threatened to delay the launch, countdown preparations proceeded on schedule, and the clouds and rain dissipated just in time for the launch weather officer to give a Go for launch during the final T-minus 4 minute hold.

Liftoff of the three-stage Delta 7425 occurred at the opening of its launch window, at 2:47:41.366 a.m. EDT, 3 July 2002. Spaceflight Now’s Justin Ray stayed up into the wee hours of the morning and braved the rainy weather at the press site to proffer yet another quality mission status report. (As this reporter was fast asleep long before the terminal count, readers interested in further details of the launch are advised to read Justin’s report.)

Sixty-four minutes after liftoff, CONTOUR separated from the Delta third stage to enter a highly-elliptical orbit. It will remain in this orbit until 15 August, when an on-board Thiokol Star-30 solid motor will fire near perigee to place the craft in a heliocentric, Earth-return orbit.

Over the next few years, CONTOUR will use several Earth gravitational assists to encounter comet Encke in 2003 and comet Schwassmann-Wachmann 3 in 2006. During these encounters it will use its Neutral Gas and Ion Mass Spectrometer and its Comet Impact Dust Analyzer to determine the chemical composition of the comets. CONTOUR is the sixth mission in NASA’s Discovery Program* of small, specialized solar system probes.

28-May-02 | Solar storms

A recent spate of strong solar storms has provided an opportunity for TIMED (Delta 289) to give scientists “important new information on the final link in the Sun-Earth Connection chain of physical processes that connect the Sun and Earth.” Other spacecraft in the NASA fleet that are adding to the big picture are ACE (Delta 247), IMAGE (Delta 277), Polar (Delta 233), and Wind (Delta 227). (NASA Press Release, 28-May-02)

28-May-02 | Water on Mars… or under it

Scientists using the gamma ray spectrometer aboard 2001 Mars Odyssey (Delta 284) have been surprised to discover massive quantities of water ice — enough to fill Lake Michigan twice over, much more than anyone expected — lying just under the surface of the south pole. (NASA Press Release, 28-May-02)

23-May-02 | Ball Aerospace to build NPP

Ball Aerospace has been selected to provide the spacecraft bus, instrument integration, testing, and on-orbit checkout for NPP, scheduled to launch aboard a Delta II in 2006. NPP, a joint NASA/NOAA mission, is a nested acronym that stands for National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project, and is a continuation of the EOS (Earth Observing System), of which two satellites (Terra and Aqua) are currently in orbit. (NASA Press Release, 22-May-02)

06-May-02 | Delta flight 291 – Aqua

Following a flawless countdown that NASA’s launch manager characterised as “a snoozer,” Delta flight 291 launched on Saturday, 4 May, to put Aqua into its proper orbit. Official liftoff time was 09:54:58:290 GMT, at the opening of a ten-minute launch window.

This launch of a two-stage Delta 7920-10L was a significant one for Vandenberg AFB. It was the fourth Delta in a row to launch from the west coast range. The only other time this has happened was back in 1971-72, when Delta still had the convenience of working from two launch pads at once. (Space Launch Complex 2-East was decommissioned in 1972; today only the concrete apron remains and the site is used for equipment storage.) In fact, this is the only time SLC-2W has hosted more than two consecutive launches. Kudos to the entire Delta team for their hard work in the wilds of the central California coast.

The flight had a number of other notable aspects. It was the first flight of Boeing’s new stretched-length payload fairing, designated “10L” and three feet longer than the standard 10-foot-diameter composite fairing; it was chosen to accomodate Aqua’s large dimensions. Being a polar-orbit flight, the ground stations used to track the rocket ran the gamut of terrestrial climes, as it passed over McMurdo Sound, Antarctica, Malindi, Kenya, and Thule, Greenland, during its ascent. During a long second-stage coast phase, Aqua’s sensitive instruments required the vehicle to enter a passive thermal control, or “barbeque” roll, to equalize the sun’s heating effects. Finally, spacecraft deployment was performed using an uncommon method to avoid imparting tip-off rates to the payload. Rather than the typical spring-loaded release from the attach fitting, after the retaining clamp and secondary latches were released the Delta second stage used its helium thrusters to slowly back away from the spacecraft.

Aqua, formerly known as EOS-PM, is a NASA orbiter carrying six state-of-the-art instruments to comprehensively study Earth’s water cycle, including “atmospheric temperature and humidity profiles, clouds, precipitation and radiative balance; terrestrial snow and sea ice; sea surface temperature and ocean productivity; [and] soil moisture.” It was originally planned to launch in late 2000, but myriad problems related mainly to spacecraft readiness resulted in cumulative delays of about a year and a half. Over the next four months the satellite will be tested, calibrated, and boosted into a 438 nautical mile operational orbit, before beginning its 6-year science mission.

30-Apr-02 | Coming Soon!

To Reach the High Frontier: A History of U.S. Launch Vehicles, edited by NASA Chief Historian Roger D. Launius and Dennis R. Jenkins, will be published by the University Press of Kentucky in August 2002. It includes chapters on all the major families of American launch vehicles, from the Navaho project of the 1950s, to the expendable Atlas, Titan, and Delta rockets, to the Space Shuttle and discussions of other reusable vehicle concepts. “Delta: The Ultimate Thor” is an extensive overview of Delta history and development written by yours truly (but in case you think this is a totally shameless plug, I won’t be getting any royalties from the book). To order, click here.

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