SpaceX Falcon 9 v1.1 - Jason 3 - SLC-4E Vandenberg - Jan 17, 2016 - DISCUSSION

[deruch]

Recent announcement of the Port of Los Angeles as the home port for SpaceX's West Coast ASDS included statements that suggested Jason-3 will be a downrange recovery attempt.

http://losangeles.cbslocal.com/2015/06/18/spacex-planning-to-base-rocket-spacecraft-retrieval-at-port-of-los-angeles/

SpaceX representatives said they want to move their vessels – including a land platform – into berths at the port by July, with the retrievals expected to begin in August. (emphasis added)

[ChefPat]

Recent announcement of the Port of Los Angeles as the home port for SpaceX's West Coast ASDS included statements that suggested Jason-3 will be a downrange recovery attempt.

http://losangeles.cbslocal.com/2015/06/18/spacex-planning-to-base-rocket-spacecraft-retrieval-at-port-of-los-angeles/

SpaceX representatives said they want to move their vessels – including a land platform – into berths at the port by July, with the retrievals expected to begin in August. (emphasis added)

Maybe they're just covering all the bases.

[jacqmans]

Packaged in its shipping container, the Jason-3 satellite is delivered to Vandenberg Air Force Base in California aboard a Boeing 747 transport aircraft. The landing took place at 10:34 a.m. PDT (1:34 p.m. EDT) on June 18, 2015. Built at Thales Alenia Space in France, Jason-3 is scheduled to lift off atop a SpaceX Falcon 9 rocket on Aug. 8, 2015. NASA will launch the satellite for NOAA, the National Oceanic and Atmospheric Administration, the French space agency -- National Centre for Space Studies, and EUMETSAT, the European Organization for the Exploitation of Meteorological Satellites. Data from Jason-3 will provide information about oceans that forecasters need to better predict severe weather and devastating hurricanes before they arrive onshore. Photo credit: NASA/Mark Mertz

[darkenfast]

Cargolux doesn't spend much money on aircraft markings.  I can't even make out a tail number.

[Galactic Penguin SST]

SFN is now showing a launch time of 8:47 pm Pacific on August 8 (03:47 UTC on August 9). 

[CJ]

Looks like near zero chance of RTLS for this mission.

The FCC filing,

https://apps.fcc.gov/oetcf/els/reports/STA_Print.cfm?mode=current&application_seq=66365&RequestTimeout=1000

Shows a landing on ASDS, not Vandy.

It also shows that the ASDS will be just 35 miles from the pad, so at least they'll be doing an almost-RTLS, because this would involve a boostback burn far larger than they've ever done before. (the closest previous ASDS proximity to the pad for recovery attempts was about 210 miles, I think). 

HAt tip; I noticed this on redit.

 

[deruch]

Looks like near zero chance of RTLS for this mission.

The FCC filing,

https://apps.fcc.gov/oetcf/els/reports/STA_Print.cfm?mode=current&application_seq=66365&RequestTimeout=1000

Shows a landing on ASDS, not Vandy.

It also shows that the ASDS will be just 35 miles from the pad, so at least they'll be doing an almost-RTLS, because this would involve a boostback burn far larger than they've ever done before. (the closest previous ASDS proximity to the pad for recovery attempts was about 210 miles, I think). 

HAt tip; I noticed this on redit.

[cscott]

I think speculation has been that the licensing and planning have been for *both*, keeping their options open.  Licensing is long lead time. So the fact that the ASDS is licensed to operate just means that SpaceX *can* do an ASDS landing, not that they will (or won't).

[Kabloona]

The application does say the transmitters will be located either on VAFB or offshore downrange (ie on the barge), so it seems to leave both options open.

[CJ]

The application does say the transmitters will be located either on VAFB or offshore downrange (ie on the barge), so it does seem to leave both options open.

This seems to be the relevant bit;

This request is limited to the TC uplink, transmitting either from an offshore boat/barge or an onshore station at VAFB. The link will also be checked-out prior to launch, at SLC-4E. Launch vehicle flight communications for this mission are covered by a separate RFA.

Anyone have any idea what "TC uplink" means? What sort of transmitters are these?

[Steven Pietrobon]

TC might mean telecommand. Uplink means from the ground to the vehicle.

[cscott]

TC uplink = "telecommand uplink", usually used in conjunction with "TM downlink" = "telemetry downlink".  The strange thing is the "launch vehicle flight communications are covered under a separate RFA" business.  I'm guessing that this license is for commanding the stage pre-launch (checkout) and post-recovery (safing).  For regulatory or technical reasons, communications during flight are done under a separate license.  I wonder if that could be found.

[meekGee]

TC uplink = "telecommand uplink", usually used in conjunction with "TM downlink" = "telemetry downlink".  The strange thing is the "launch vehicle flight communications are covered under a separate RFA" business.  I'm guessing that this license is for commanding the stage pre-launch (checkout) and post-recovery (safing).  For regulatory or technical reasons, communications during flight are done under a separate license.  I wonder if that could be found.

Well it says "The link will also be checked-out prior to launch" - this language makes it less likely they're talking about a pre-launch link. (Also, isn't pre-launch communication done through a wired connection?)

Curious about the in-flight set up though.

EDIT:  In the body of the application, it says "Experimental first-stage recovery operation", so this license is indeed for post-flight.

But clearly they can talk to the stage in the last phase of the landing, the question is whether they do or not.

[Jarnis]

Could be for uplinking commands for safing the stage after landing.

[CJ]

Thank you to those above to explained what the TC meant.

Could be for uplinking commands for safing the stage after landing.

That's my current guess.

Also, IMHO the frequency (2090 mhz) is significant for this discussion. That's a line-of-sight frequency. So, that means that they could not have the transmitter at Vandy if they want to send commands to a F9 sitting on the deck of ASDS 35 miles away. Not without a 1000 foot tower (which would put the horizon 38 miles away), and the application lists max 100 feet, if I remember right.

My guess, based on this and the posts above, is that they are indeed keeping their options for a RTLS open.

My further guess is that there is at best a very slim chance for RTLS being approved, and zero unless CRS-7 is approved.

Does anyone happen to know roughly where the landing pad at Vandy is? I've been assuming it's close to the SpaceX launch complex (SLC-4), but I may well be wrong. However, if it is close to SLC-4, the risk to other facilities from a RTLS appears to be very minimal; SLC-4 is very close to the shoreline, with nothing on any likely launch or RTLS trajectory between it and the sea. There is a rail line between the pad and the sea, but that's closed for launches anyway. 

 

[Kabloona]

Landing pad is at SLC-4W, just west of the launch pad at SLC-4E.

[CJ]

Landing pad is at SLC-4W, just west of the launch pad at SLC-4E.

Thanks!!!

Then in that case, the F9 wouldn't need to overfly anything except the rail line for a RTLS on this launch azimuth. IMHO, that means there's still a chance a RTLS might be approved if CRX-7 goes well.

Edit; after having another look at Helodriver's pics in the Vandenburg thread, I think I see where the pad is. If I'm right, the landing F9 on this mission would need to overfly SLC-4W. I made a post in the Vandenburg thread
http://forum.nasaspaceflight.com/index.php?topic=35480.msg1392582#msg1392582

with a pic plus some other issues general to the pad and not limited to this mission.

[Kabloona]

 .?? The landing would be *at* SLC-4W, not overflying it.

[CJ]

.?? The landing would be *at* SLC-4W, not overflying it.

My bad. I wasn't aware that SLC-4W was being demolished, and thus misread your "at" to mean "in very close proximity to".

Jason 3 looks to have a target inclination of 66 degrees, so does that give us an azimuth of about 151 degrees for this launch? (I may have bungled the math).

[Kabloona]

Yes, I get an azimuth of 150 degrees.