Author Topic: SpaceX Falcon 9 v1.1 - SES-8 - DISCUSSION THREAD (Read 611315 times)

Robotbeat · « **Reply #20 on:** 03/14/2011 07:03 pm »

Quote from: Danderman on 03/14/2011 05:11 pm

The industry standard is to launch satellites to GTO with a difference between the GTO orbit and GEO being 1500 m/s delta-V. That delta-V difference can be inclination change or velocity or both.

Since the Block 1 Falcon 9 does not put anywhere close to the nominal 10 tons into LEO, it is therefore impossible for it to inject 4 tons into GSO, as mentioned in the above quote. What may be possible is to put the 4 tons into GTO. However, someone here did the calculations and determined that 2.5 tons to GTO is the probable limit for a Block 1 F9.

So what? They've been putting all their eggs in the Block 2 basket for years, now.

ugordan · « **Reply #21 on:** 03/15/2011 02:55 pm »

Quote from: Danderman on 03/14/2011 06:01 pm

Quote from: Robotbeat on 03/14/2011 05:29 pm
Predicted performance figures are often not reached right away, and it shouldn't (and wasn't, if you read some of the older posts around here) be surprising.

No one is suggesting that performance figures should be met right away. But, they should be met Some Day. In the case of SpaceX, specific performance values are never met, they are "leapfrogged".

Quote from: Jeff Foust

SES CEO Bausch says Falcon 9 not ready for SES-8 launch; needs new fairing and upgraded engine, but believes ready by 2013

http://twitter.com/jeff_foust/status/47667295140589568

Nate_Trost · « **Reply #22 on:** 03/15/2011 02:57 pm »

Interesting, I think that's the first suggested timeframe we've seen for availability of Block 2.

Danderman · « **Reply #23 on:** 03/15/2011 03:37 pm »

Quote from: ugordan on 03/15/2011 02:55 pm

Quote from: Jeff Foust
SES CEO Bausch says Falcon 9 not ready for SES-8 launch; needs new fairing and upgraded engine, but believes ready by 2013

"The SES-8 satellite is scheduled to launch in the first quarter of 2013 from SpaceX's Launch Complex 40 at the Air Force Station at Cape Canaveral, Florida."

If I had to bet money, I would bet that the SES launch on F9 will ultimately be transmogrified into launch on Falcon 9 with the Merlin 2 OR Falcon/Raptor, if it doesn't disappear from the manifest like HYLAS. This is the downside of the "leapfrogging" approach used by SpaceX.

ugordan · « **Reply #24 on:** 03/15/2011 03:49 pm »

Quote from: Danderman on 03/15/2011 03:37 pm

If I had to bet money

Go right ahead.

Me, I'll stick with the opinion that SES people have had more insight into where SpaceX is right now, what it needs to do to get where it needs to and the risk of not being able to do it than uninformed observers here. That includes any forum "proof" on what F9 can and what it cannot do.

antonioe · « **Reply #25 on:** 03/15/2011 07:51 pm »

Iguess nobody has noticed who is the SES-8 manufacturer...

Robotbeat · « **Reply #26 on:** 03/15/2011 07:53 pm »

Quote from: antonioe on 03/15/2011 07:51 pm

Iguess nobody has noticed who is the SES-8 manufacturer...

Congratulations, Orbital Sciences!

(This is the problem with this board... it's so launch-vehicle-centric that it fails to give proper credit to those who actually make the spacecraft, which is usually more expensive than the launch vehicle, often FAR more expensive!)

robertross · « **Reply #27 on:** 03/15/2011 07:54 pm »

Quote from: antonioe on 03/15/2011 07:51 pm

Iguess nobody has noticed who is the SES-8 manufacturer...

HA!!

Orbital!!

http://www.ses.com/ses/siteSections/newsroom/Latest_News/index.php?pressRelease=/pressReleases/pressReleaseList/11-02-17/index.php

Orbital Sciences to build new satellite for launch in 2013 to provide incremental capacity

The Hague, February 17, 2011 - In order to respond to the strong demand for additional DTH capacity in Asia, SES WORLD SKIES, a division of SES S.A. (Euronext Paris and Luxembourg Stock Exchange: SESG), today announced that it has commissioned the SES-8 spacecraft from Orbital Sciences Corporation (NYSE: ORB) for a launch in the first quarter of 2013.

SES-8 will feature 33 high-power Ku-band (36 MHz-equivalent) transponders and will be co-positioned with the NSS-6 satellite at the orbital location of 95 degrees East. SES-8 is a medium-sized satellite with beams focused on South Asia (India) and Indo-China (Thailand, Vietnam, Laos) to support existing DTH customers with back-up and growth transponder capacity. The spacecraft will be built on Orbital's flight-proven STAR spacecraft platform and will generate approximately 5.0 kilowatts of payload power.

The 95 degrees East orbital slot is a cornerstone of the SES strategy in Asia. NSS-6, the satellite currently located at 95 degrees East is operating at 95%+ fill rates and is home to the largest DTH operator in India, Dish TV, with over 9.6 Million subscribers. India is the fastest growing DTH market in the world with an estimated 30 million subscribers and is projected to overtake the US as the largest DTH market. The 95 degrees East orbital location is also home to major CATV and DTH operations for the Thai market supporting 4.5 Million viewers. In addition, 95 degrees East supports key customers in the Middle East, Afghanistan, Australia, Papua New Guinea, and Korea, including the Armed Forces Radio and Television Service (AFRTS) Network distribution platform. SES continues to see robust growth in the emerging markets, particularly in West Asia, India, South East Asia. SES-8 thus provides the opportunity to support key strategic customers with their growth plans and to build on the extremely valuable video and data neighborhood.

States Rob Bednarek, President and CEO of SES WORLD SKIES: "SES-8 will provide incremental capacity at the well-established orbital position of 95 degrees East, which already features five DTH platforms and supports key telecom infrastructure and broadband networks across the Middle East and Asia. SES-8 is SES' sixth procurement of a STAR series spacecraft from Orbital, and we look forward to another successful mission that will provide our customers in Asia with new, state-of-the-art capacity for growth."

Commenting on the contract award, Christopher Richmond, Orbital's Senior Vice President and head of its communications satellite unit, said, "We are very appreciative that SES continues to rely on our STAR satellites as a mainstay in their global fleet. With three Orbital-built spacecraft already deployed in the SES fleet, along with the two currently in production, the new SES-8 satellite will be the latest successful collaboration between our two companies. We will continue to work closely with the SES team to build on our already solid relationship and help ensure SES meets the needs of its customers."

Comga · « **Reply #28 on:** 03/15/2011 11:06 pm »

Quote from: antonioe on 03/15/2011 07:51 pm

I guess nobody has noticed who is the SES-8 manufacturer.

What do you mean "nobody", Dr. E.
Some of us duly noted your win. It just wasn't the topic here.

McDew · « **Reply #29 on:** 03/16/2011 12:08 am »

Quote from: ugordan on 03/15/2011 02:55 pm

Quote from: Jeff Foust
SES CEO Bausch says Falcon 9 not ready for SES-8 launch; needs new fairing and upgraded engine, but believes ready by 2013

Bausch also stated that Falcon 9 will need a succesful launch of the upgraded engine and the new fairing prior to launching the SES-8 mission.

Antares · « **Reply #30 on:** 03/16/2011 03:32 am »

Physics makes strange bedfellows.

Robotbeat · « **Reply #31 on:** 03/16/2011 04:21 am »

Quote from: Antares on 03/16/2011 03:32 am

Physics makes strange bedfellows.

apace · « **Reply #32 on:** 03/16/2011 09:22 am »

Quote from: McDew on 03/16/2011 12:08 am

Quote from: ugordan on 03/15/2011 02:55 pm
Quote from: Jeff Foust
SES CEO Bausch says Falcon 9 not ready for SES-8 launch; needs new fairing and upgraded engine, but believes ready by 2013

Bausch also stated that Falcon 9 will need a succesful launch of the upgraded engine and the new fairing prior to launching the SES-8 mission.

Wonder if SpaceX build their fairing self or buying one from RUAG.

Skyrocket · « **Reply #33 on:** 03/16/2011 11:15 am »

Quote from: apace on 03/16/2011 09:22 am

Wonder if SpaceX build their fairing self or buying one from RUAG.

They build their own. One was originally to be flown on the maiden flight of F-9, but the development was not finished at this time. But it should be ready until 2013.

ugordan · « **Reply #34 on:** 03/21/2011 12:27 pm »

The Space News article on the contract appears to have been updated with some additional info and quotes. I haven't seen the projected mass of the satellite anywhere else:

Quote

SES-8 is expected to weigh around 3,600 kilograms at launch and would be too heavy for the Europeanized Soyuz

I take it the injection would be to a GTO which is 1500 m/s short of GEO (valid assumption?). On paper, Block 2 is able to inject 4500 kg to 1800 m/s short (F9 UG fig. 4.1.7), but performance drops like a rock if any inclination reduction is done from the Cape during 2nd MVac burn.

To be able to lift 3600 kg to GEO-1500 m/s would require the delta-V kit. The much less expensive inclination change at GTO apogee could partially explain why the performance numbers seem unrealistically high compared to an Atlas 401 which typically does a two-burn profile with the (more expensive) inclination change during 2nd burn.

Jim · « **Reply #35 on:** 03/21/2011 12:40 pm »

I don't understand the above post. Altas only does inclination changes when there is excess performance.

ugordan · « **Reply #36 on:** 03/21/2011 12:49 pm »

Yes, but the point I'm making is Atlas does so during the 2nd burn so that inclination change is more costly than if it's done at GTO apogee. So the vastly higher Isp on a Centaur doesn't completely blow away a vehicle that can "cheat" with a lower Isp apogee kick inclination change.

I don't know about typical Proton insertions, but seeing as how one possible backup to this bird could be an Ariane suggests SES-8 would "like to" end up in a transfer that's 1500 m/s short of GEO.

Jim · « **Reply #37 on:** 03/21/2011 01:51 pm »

Quote from: ugordan on 03/21/2011 12:49 pm

Yes, but the point I'm making is Atlas does so during the 2nd burn so that inclination change is more costly than if it's done at GTO apogee. So the vastly higher Isp on a Centaur doesn't completely blow away a vehicle that can "cheat" with a lower Isp apogee kick inclination change.

It isn't costly, if it is using excess launch vehicle performance, it is a benefit.

For commercial missions, none of the US launch vehicles make the inclination change at GTO apogee, it is always the spacecraft.

ugordan · « **Reply #38 on:** 03/21/2011 04:48 pm »

Quote from: Jim on 03/21/2011 01:51 pm

It isn't costly, if it is using excess launch vehicle performance, it is a benefit.

When I say cost I mean the delta-V requirement for a degree of inclination change. Obviously this is more costly deeper into the gravity well.

Jim · « **Reply #39 on:** 03/21/2011 04:59 pm »

Quote from: ugordan on 03/21/2011 04:48 pm

Quote from: Jim on 03/21/2011 01:51 pm
It isn't costly, if it is using excess launch vehicle performance, it is a benefit.

When I say cost I mean the delta-V requirement for a degree of inclination change. Obviously this is more costly deeper into the gravity well.

I understand the orbital mechanics. I still don't understand your point.

Falcon 9 and Atlas V will fly the same trajectories for GTO missions. Falcon 9 will do the same things, as Atlas if they have known prelaunch excess performance, such as inclination reduction, super or sub synchronous injection.