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-   -   Zuma & FH launches (http://www.oldrocketforum.com/showthread.php?t=17057)

blackshire 01-04-2018 09:46 AM

Zuma & FH launches
 
Hello All,

Tomorrow night (Friday, January 5th), the 2-hour launch window for the Falcon 9 carrying the mysterious Zuma satellite will open at 8:00 PM EST (that's 0100 GMT Saturday morning, for those living a few Time Zones east of Florida). Live coverage of the launch, from Pad 40 at Cape Canaveral, can be seen *here* (see: http://spaceflightnow.com/2018/01/0...tatus-center-2/ ). Because of the "sensitive" payload, the normal video coverage is expected to cease at around staging, but because the first stage will--if all goes well--return to land at LZ-1 (Landing Zone-1) at the Cape, the coverage may just be switched to the first stage. The live launch webcast will begin tomorrow evening about 15 minutes before the launch, *and*:

SpaceX has released close-up photographs and video of their first Falcon Heavy vehicle on Pad 39A, which can be seen here: http://spaceflightnow.com/2018/01/0...avys-pad-debut/ . A pre-launch, on-pad static firing test--of all 27 Merlin rocket engines of the core first stage and the two boosters--is planned for this month, with the launch expected to occur soon afterward. Both events will be spectacular to watch!

blackshire 01-05-2018 12:43 AM

Instead of launching the Zuma satellite Friday evening, SpaceX instead carried out more propellant loading tests. The latest update (see: http://spaceflightnow.com/2018/01/0...tatus-center-2/ [pictures were also uploaded here]) says:

Following the additional testing at the launch pad today, SpaceX has confirmed a new launch date of Sunday, January 7 for the Zuma mission.

SpaceX

@SpaceX
Team at the Cape completed additional propellant loading tests today. Extreme weather slowed operations but Falcon 9 and the Zuma spacecraft are healthy and go for launch—now targeting January 7 from Pad 40 in Florida.

3:25 PM - Jan 4, 2018

blackshire 01-08-2018 02:11 AM

Zuma's launch was apparently successful (see: http://spaceflightnow.com/2018/01/0...u-s-government/ ), with some interesting camera views (liftoff occurred ~10 seconds after 13:49 *here*, see: http://www.youtube.com/watch?time_c...0&v=0PWu3BRxn60 ). The first stage returned and landed on LZ-1, which was unlit except by the engine exhaust. Much of its descent through the atmosphere, seen by a ground-based camera (they also showed the on-board view, via split-screen), was visible by what looked like "after-burning" from the engine nozzles, between the re-entry and landing burns.

tbzep 01-08-2018 08:20 AM

Isn't it awesome that Space-X has made 1st stage return seem routine? :cool:

I hope F9H doesn't break up just so they can have the chance to drop three on the bullseyes at the same time.


.

blackshire 01-08-2018 08:40 AM

Quote:
Originally Posted by tbzep
Isn't it awesome that Space-X has made 1st stage return seem routine? :cool:

I hope F9H doesn't break up just so they can have the chance to drop three on the bullseyes at the same time.


.
Yes--I wonder if they dared to hope that it would work so consistently. But knowing what can so easily turn a triumph into a tragedy (and they know it in far more detail than I), I wouldn't be surprised if the SpaceX folks will always--at least to an extent--"hold their breath" until each landing (like the Moon shuttle captain in "2001: A Space Odyssey"), and:

I'm hoping the inaugural Falcon Heavy flight later this month works better than we've been "psychologically inoculated" against, not only to see the first (non-rover) car in space, but also so that the other pending FH missions won't be further delayed--and yeah, I want to see a "double, then downrange encore" booster landing, too... :-)

foamy 01-09-2018 09:54 AM

So, did the ZUMA satellite fail, or is it just a DOD hush to make it look as if it did (perhaps an unintended [happy] consequence)?

SpaceX reported their rocket's flight as nominal.

tbzep 01-09-2018 10:45 AM

I've seen one reference that it may have failed to separate from the second stage, but I haven't looked for any other sources. Space-X claimed that the Falcon 9 operated nominally.

dlazarus6660 01-09-2018 08:46 PM

According to the CBS news, it failed to make low earth orbit and fell into the Indian ocean with the second stage still attached. :eek:

blackshire 01-10-2018 01:50 AM

Hmmm...if it fell into the Indian Ocean with the second stage still attached, *and* the Falcon 9 performed nominally, this suggests that the Zuma satellite may have had either a solid propellant third stage motor (an AKM--Apogee Kick Motor--either attached, or integrated into the spacecraft, as with some satellites) or a liquid propellant engine (or a set of thrusters) that would fulfill the same function as an AKM. These propulsion systems are used to either boost satellites into higher orbits or (if a satellite is so heavy that it's close to--or a bit beyond--the launch vehicle's maximum payload capability to the desired orbit) to complete the orbital injection process. If Zuma was equipped with any of these propulsion systems, it would have been rendered useless if Zuma failed to separate from the Falcon 9 second stage (the payload adapter was supplied by Northrop Grumman; more on this below). Also:

Whenever the Falcon 9 (or any launch vehicle, especially a commercial one) fails, its manufacturer "stands down" and delays subsequent launches until the cause of the failure is determined (or its most likely cause or causes is/are identified, because sometimes the "smoking gun" is impossible to find), and SpaceX hasn't done this, and:

This *lack* of a launch vehicle "stand down" also occurs if a mission fails due to a spacecraft malfunction, but its launch vehicle does its job properly. The Titan IIIA launch of the LES 1 (Lincoln Experimental Satellite 1) spacecraft on February 11, 1965 is an example of this. LES 1 failed to reach its intended highly-eccentric (2,800 km x 15,000 km) orbit and achieved few of its objectives because its attached solid propellant kick motor failed to fire due to an ordnance wiring error, but the Titan IIIA properly injected LES 1 into its planned initial 2,800 km circular parking orbit, so the Titan IIIA test series wasn't delayed. (LES 1, incidentally, has begun transmitting again [see: http://www.pe0sat.vgnet.nl/satellite/sat-history/les-1/ and http://en.wikipedia.org/wiki/Lincol...ental_Satellite ] decades after it ceased transmitting in 1967, much like the also long-dead AMSAT-OSCAR 7 [see: http://en.wikipedia.org/wiki/AMSAT-OSCAR_7 ] amateur radio satellite.) In addition:

The Zuma launch was delayed for almost two months due to concern about its Falcon 9's payload fairing, following testing of a payload fairing for another customer's Falcon 9 (see: https://en.wikipedia.org/w/index.ph...ah1ce34tmx0gbsy ), and apparent spacecraft/second stage separation failure--according to this article--may have been caused by the Northrop Grumman-supplied payload adapter. As well:

During the launch coverage (see: www.youtube.com/watch?v=CArCgeXn3AQ ), the SpaceX presenter mentioned--at about the 3:44 point--that payload fairing separation "should occur any second now," but not until the ~5:27 point (well after the first stage's boost-back burn) did he mention the fairing again, and in a rather odd way: "All right, so we'll address the payload deployment here in a second, once we have more information." Then he moved on to describing the first stage's return for a few seconds, then confirmed that the fairing had separated. Now:

While this doesn't necessarily mean that there was any problem with the fairing separation, I wonder if maybe it (perhaps one half) "hung up" for a moment? If so--maybe Zuma was a large spacecraft that took up most of the payload envelope volume?--such a "hang up" could have damaged the satellite, but even if there was no damage, seeing the two fairing halves separate at different times and/or different velocities (via the on-board camera and/or radar) could have delayed the announcement of this mission milestone. I don't know if any of these things occurred, but such unexpected events could have been responsible for the unusual coverage. (A more prosaic possibility is that SpaceX wanted to "err on the side of caution" concerning security, but I doubt this, because SpaceX has launched other secret payloads and forthrightly announced fairing separation after cutting to Stage 1-only video coverage [such as at the ~15:20 point in the following video of the NROL-76 launch in May, see: www.youtube.com/watch?v=EzQpkQ1etdA ].)

aeppel_cpm 01-10-2018 07:57 AM

I saw a report from the amateur sat trackers that the 2nd stage had been sighted over east Africa venting fuel (normal) at a time/place that implied a -higher- than initially guessed orbit.

And the 2nd stage is in-orbit when it's done. Other second stages have taken weeks to months to deorbit. If it came down in the Indian Ocean, it was because of a disposal burn - also common practice.

So, if the satellite didn't separate correctly, and a pre-programmed disposal burn brought it back down, I think the 2nd stage would have re-entered long - further SE of Australia than normal - because of the extra (unplanned) mass of the satellite making the disposal burn less effective.


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