SpaceX Falcon 9 v1.1 - Thaicom 6 - DISCUSSION THREAD

[Roy_H]

Do we know if Thaicom 6 will follow the same strategy, or will the rocket do the whole plane change?

I don't think it is desirable for the rocket to do the whole plane change. As it is the spent upper stage loops over the ring of geostationary satellites. If the rocket was used to get to zero degrees then the spent stage would pass through the ring of satellites, and although the odds of a collision would be small, why take the chance at all?

[douglas100]

It takes less delta V to change plane at apogee as opposed to perigee. This has been done by the upper stage of the launch vehicle on some missions. But most commercial comsats use on board propulsion.

[LegendCJS]

Elon said they'd max the performance of both these flights.

Cheers, Martin

I think you are referring to the statement that they will give maximum margin for both of these flights, in-order to have best chance of success in case of something like an engine out.  To me saying max margin/ reserves for contingency is different than saying they will maximize performance (I interpret max performance as planning to burn every last drop of fuel/  burn to empty in the nominal flight, something nobody ever does).

[Chris Bergin]

Right, you won't find a more comprehensive launch article than this one from William Graham!

http://www.nasaspaceflight.com/2014/01/spacex-falcon-9-v1-1-launch-thaicom-6/

Get it shared, retweeted, whatever - too many people sit on their hands here.

Setting up the required threads for launch day shortly.

[QuantumG]

Right, you won't find a more comprehensive launch article than this one from William Graham!

http://www.nasaspaceflight.com/2014/01/spacex-falcon-9-v1-1-launch-thaicom-6/

Fantastic article. A real wealth of information in there.

[edkyle99]

3,016 kg satellite at liftoff, aiming for a 295 x 90,000 km x 22.5 deg orbit.  Slightly (122 kg) lighter than SES 8 and going 10,000 km higher.

 - Ed Kyle

[MP99]

Elon said they'd max the performance of both these flights.

Cheers, Martin

I think you are referring to the statement that they will give maximum margin for both of these flights, in-order to have best chance of success in case of something like an engine out.  To me saying max margin/ reserves for contingency is different than saying they will maximize performance (I interpret max performance as planning to burn every last drop of fuel/  burn to empty in the nominal flight, something nobody ever does).

Thanks, yes, that is what I should have said.

Cheers, Martin

[PerW]

The presskit
http://www.spacex.com/sites/spacex/files/spacex_thaicom6_presskit.pdf

[boinc]

does anyone know something about the weather? whats the weather go?

[fatjohn1408]

Only 3016 kg. I thought it was higher.

Anyway orbit is going to 295x90,000x22.5
That is a very high SSTO.

[Galactic Penguin SST]

Sooo.....is the vehicle on the pad already? (assuming same pre-launch flow as the SeS-8 launch) Anyone at the Cape can help to see what's going on? 

[Garrett]

Sooo.....is the vehicle on the pad already? (assuming same pre-launch flow as the SeS-8 launch) Anyone at the Cape can help to see what's going on? 

according to the press kit, the rocket is erected at the pad 24 hours before launch.

[pospa]

Sooo.....is the vehicle on the pad already? (assuming same pre-launch flow as the SeS-8 launch) Anyone at the Cape can help to see what's going on? 

according to the press kit, the rocket is erected at the pad 24 hours before launch.

... and already powered on in T -13:30

[ChefPat]

Only 3016 kg. I thought it was higher.

Anyway orbit is going to 295x90,000x22.5

90,000 kilometers at apogee? Is this correct? AIUI SES-8 went to Super Synchronous Orbit but Thaicom-6 was going to a standard GSO. If it's going up to 90,000 kilometers, is it going to a Super Synchronous Orbit too?

[guckyfan]

3,016 kg satellite at liftoff, aiming for a 295 x 90,000 km x 22.5 deg orbit.  Slightly (122 kg) lighter than SES 8 and going 10,000 km higher.

 - Ed Kyle

Is that because it is lighter or because they factor in the higher than expected performance of the SES-8 flight?

[guckyfan]

Only 3016 kg. I thought it was higher.

Anyway orbit is going to 295x90,000x22.5

90,000 kilometers at apogee? Is this correct? AIUI SES-8 went to Super Synchronous Orbit but Thaicom-6 was going to a standard GSO. If it's going up to 90,000 kilometers, is it going to a Super Synchronous Orbit too?

There is that discrepancy in the press kit. They write GTO and then give these data, which is SSTO.

[macpacheco]

3,016 kg satellite at liftoff, aiming for a 295 x 90,000 km x 22.5 deg orbit.  Slightly (122 kg) lighter than SES 8 and going 10,000 km higher.

 - Ed Kyle

Is that because it is lighter or because they factor in the higher than expected performance of the SES-8 flight?

It looks like it's the reduced weight. It wouldn't be wise to announce a target orbit based on a single launch that went beyond expectations. They need a pattern of positive data before they can count on that as a sure thing.

PS: This is the launch update thread, questions like this don't really belong here...

[fatjohn1408]

3,016 kg satellite at liftoff, aiming for a 295 x 90,000 km x 22.5 deg orbit.  Slightly (122 kg) lighter than SES 8 and going 10,000 km higher.

 - Ed Kyle

Is that because it is lighter or because they factor in the higher than expected performance of the SES-8 flight?

It looks like it's the reduced weight. It wouldn't be wise to announce a target orbit based on a single launch that went beyond expectations. They need a pattern of positive data before they can count on that as a sure thing.

PS: This is the launch update thread, questions like this don't really belong here...

FYI the new target orbit (assuming a 185x185x27° parking orbit) requires 2960m/s.
The SES-8 target orbit required 3015 m/s from this parking orbit.

The SES-8 target orbit was thus energetically more difficult to reach for the Falcon 9. This is true for 185km parking orbits with an inclination bigger than 23.8°.

Both orbits are 1500 m/s away from GEO.

[fatjohn1408]

The first burn of the second stage is going to be 335 seconds. The duration of the second burn is unknown. 

[Zaran]

From the update thread:

3,016 kg satellite at liftoff, aiming for a 295 x 90,000 km x 22.5 deg orbit.  Slightly (122 kg) lighter than SES 8 and going 10,000 km higher.

 - Ed Kyle

Is that because it is lighter or because they factor in the higher than expected performance of the SES-8 flight?

This is due to customer preference according to Gwynne Shotwell, she stated, I believe during the pre-launch SES-8 press teleconference, that Thaicom 6 will go higher but have a slightly higher injection inclination than SES-8.