Satellite fleet operator Telesat of Canada on Nov. 11 said it would purchase a Ku-/Ka-band broadband satellite, called Telstar 19 Vantage, to be stationed at 63 degrees west over Latin America now that it had secured an anchor customer in EchoStar’s Hughes Network Systems...
Germantown, Maryland-based Hughes, in its own announcement, said it had agreed to lease a large portion of Telstar 19 Vantage’s Ka-band — a total of 31 gigabits per second of throughput — for 15 years, with the satellite to be launched in early 2018...
Hughes said the Telesat capacity would be used for consumer broadband throughout Latin America, not just Brazil. Hughes officials have said 24 gigabits per second of throughput on Eutelsat’s satellite would serve 300,000 customers in Brazil...
Ottawa-based Telesat said Telstar 19 Vantage will carry more Ka-band than has been leased by Hughes, with the additional capacity to be directed to markets in Northern Canada, the Caribbean and the North Atlantic Ocean. A Ku-band payload will be aimed at high-throughput and conventional wideband markets in Brazil, the Andean region and the North Atlantic Ocean.
The Canadian telecom satellite operator Telesat plans to launch two multipurpose communications spacecraft aboard SpaceX Falcon rockets in 2018, the company disclosed this week in a quarterly earnings announcement.
A spokesperson for the Ottawa-based company said the new satellites, named Telstar 18 Vantage and Telstar 19 Vantage, would fly aboard Falcon 9 rockets.
estimated end-of-life mass of 3031 kg
OTTAWA, CANADA, September 15, 2017 – Telesat announced today that Bell Canada has signed a 15-year contract for substantially all of the HTS spot beam capacity over northern Canada on Telesat’s new Telstar 19 VANTAGE satellite. Bell Canada subsidiary Northwestel will use the capacity to dramatically enhance broadband connectivity for communities in Nunavut, Canada’s northernmost territory.
Telstar 19 VANTAGE is currently being built by Space Systems Loral in Palo Alto, CA. The satellite is scheduled to launch in the second quarter of 2018 on a SpaceX Falcon 9 rocket and will be co-located with Telesat’s Telstar 14R satellite at 63 degrees West, a prime orbital slot for coverage of the Americas. Once operational, Telstar 19 VANTAGE will have six distinct coverages over the Americas and North Atlantic and the most capacity in Gbps of any satellite in Telesat’s fleet.
The long-term agreement with Bell Canada marks another major pre-sale of HTS capacity on Telstar 19 VANTAGE. As previously announced, Hughes Network Systems LLC has contracted for all the South American high throughput Ka-band capacity of Telstar 19 VANTAGE. Combining Bell Canada’s long term contract with other customer commitments, Telesat has now signed long term contracts for the entire Ka-band HTS capacity on Telstar 19 VANTAGE over Northern Canada.
“The significant investment Telesat has made in Telstar 19 VANTAGE is the latest example of our decades-long record of committing major capital resources to bring advanced communications to Canada and its Northern communities” said Michele Beck, Telesat’s Vice President North American Sales. “Telesat is pleased to have concluded this important agreement with Bell Canada that will bring twenty times more capacity to the region using our new powerful, state-of-the-art satellite.”
“Our agreement with Telesat is another example of Bell’s commitment to work closely with our country’s technology leaders to roll out innovative communications network solutions that benefit Canadians everywhere,” said Stephen Howe, Bell’s Chief Technology Officer. “We look forward to delivering enhanced broadband services to Canada’s North with the new Telstar 19 VANTAGE satellite.”
Northwestel plans to implement new and improved broadband for communities across Nunavut, one of the most difficult regions in the world to serve, beginning in the second half of 2018.
“Making high-quality broadband services available to remote communities across the vast expanse of Canada’s north is a huge challenge,” said Curtis Shaw, Chief Operating Officer, Northwestel. “Northwestel looks forward to utilizing the power and capabilities of Telesat’s new state-of-the-art Telstar 19 VANTAGE satellite as part of our commitment to connect 25 communities across Nunavut to faster and more reliable broadband over the next two years.”
Tweet from SSL (https://twitter.com/sslmda/status/926087843209871365):
Last week, the Telstar 19 VANTAGE satellite began testing in our TVAC, an environment designed to simulate the harsh conditions of space.
Guessing this isn't making a NET June 17 as there has been no news of the payload reaching the Cape. Anyone have an update?
It is my understanding that the 2 Telestar data may ship out together as they will launch close together.Guessing this isn't making a NET June 17 as there has been no news of the payload reaching the Cape. Anyone have an update?
The next 3 GTO payloads are from SSL so they'll be trucked to the Cape, we may not get any notification of them arriving. It's easier to track them when they're getting flown in on Antonovs from Europe or Japan. This one is looking like July now.
It is my understanding that the 2 Telestar data may ship out together as they will launch close together.Guessing this isn't making a NET June 17 as there has been no news of the payload reaching the Cape. Anyone have an update?
The next 3 GTO payloads are from SSL so they'll be trucked to the Cape, we may not get any notification of them arriving. It's easier to track them when they're getting flown in on Antonovs from Europe or Japan. This one is looking like July now.
SSL wants to fly Telstar 19V to the Cape on an AN-124 but DOT hasn't approved the application. SSL filed a letter on the 13th asking them to reconsider and allow a flight on the 15th, but it doesn't look like that happened. Looks like they're hoping to fly in the next few days now if they can get permission.
Instead of waiting, like they usually do, Go Quest and Go Pursuit have left port with Hawk and OCISLY. Any ideas why?They did leave a few hours later. Nothing was unusual this time.
Is it not now (00:15 7/21 UTC) less than 30 hours until the opening of the window (05:50 7/22 UTC) and still no news?
Either SpaceX is doing worse than planned, and they can't get the rocket ready, or better than previously shown, and they can roll out a Block 5 F9 and launch in less than a day. In the absence of statements from SpaceX or CCAFS one's guess probably reflects one's position more than any facts on the ground.
We shall see, if not today, then tomorrow.
Do we know the exact launch mass of Telstar 19V yet? I've looked around for it but have only found the dry mass.
"Telstar 19 Vantage weighs approximately 5.4 metric tons, which means the first stage will be able to land on Of Course I Still Love You."
Do we know the exact launch mass of Telstar 19V yet? I've looked around for it but have only found the dry mass.
https://www.nasaspaceflight.com/2018/07/second-falcon-9-block-5-readying-for-static-fire-ahead-of-telstar-19v-launch/
"Telstar 19 Vantage weighs approximately 5.4 metric tons, which means the first stage will be able to land on Of Course I Still Love You."
The extra lift capability of the Falcon 9 Block 5 will allow the rocket to send the nearly 15,600-pound (7,075-kilogram) Telstar 19 VANTAGE satellite toward its operational perch in geostationary orbit more than 22,000 miles (nearly 36,000 kilometers) over the equator.
Telstar 19 VANTAGE will become the heaviest commercial communications satellite ever launched, eclipsing a record set by the TerreStar 1 telecom spacecraft, which weighed 15,234 pounds (6,910 kilograms) when it rode an Ariane 5 rocket into orbit July 2009.
It is also set to be the heaviest satellite ever launched by SpaceX into geostationary transfer orbit, the drop-off for most commercial telecom payloads.
Spaceflight Now is reporting this sat's mass is 7075kg, the heaviest GTO sat ever. Link to article: https://spaceflightnow.com/2018/07/21/record-setting-commercial-satellite-awaits-blastoff-from-cape-canaveral/
I was shocked when I read the spaceflightnow article. That’s huge and larger than the FH Arabsat 6.
7000 kg on a F9 with recovery, this is impressive.
AND if the 2nd stage basically reenters at first perigee encountered with no serious reentry burn employed...
AND if the 2nd stage basically reenters at first perigee encountered with no serious reentry burn employed...
SpaceX usually doesn't immediately deorbit the second stage on GTO flights.
AND if the 2nd stage basically reenters at first perigee encountered with no serious reentry burn employed...
SpaceX usually doesn't immediately deorbit the second stage on GTO flights.
True... I agree...
BUT if the 2nd stage does not make it around a few laps... Then we will know that the bird really helped itself in the initial published orbit figures we see... ;)
I was shocked when I read the spaceflightnow article. That’s huge and larger than the FH Arabsat 6.
7000 kg on a F9 with recovery, this is impressive.
It has more total mass than other comsats with all of that fuel, but SES-12 probably has significantly bigger dry mass. Different customers make different trade-offs.
7000kg gross and ASDS recovery... Single stick F9 B5...AND if the 2nd stage basically reenters at first perigee encountered with no serious reentry burn employed...
SpaceX usually doesn't immediately deorbit the second stage on GTO flights.
True... I agree...
BUT if the 2nd stage does not make it around a few laps... Then we will know that the bird really helped itself in the initial published orbit figures we see... ;)
If SpaceX doesn't do a deorbit burn then the second stage will be up there for a while. It's not going to deploy the satellite on a suborbital trajectory.
Gwen has said they have sand bagged their figures before. You think F9 B5 got legs? Hit recovery on GTO-1800 on 7000kg. Or you think they going for sub geosynchronous transfer orbit?
Perigee is usually at LEO, usually high up at least above 200km, high enough for the second stage to be in that orbit for a few months at least. No reason to think that this particular mission will have a lower perigee than others, it will be as normal as usual, what's going to be lower than usual will probably be the apogee, but that doesn't affect to the rate of decay of the orbit (Well, technically it affects, but because a lower apogee means a shorter orbital period so the second stage will pass more times through the perigee in less time, but it will also pass through the perigee at a lower velocity, so who knows if it really affects it in the end or not).
I was talking about the apogee affecting the decay rate, not perigee. I said about the perigee that we shouldn't expect this to be anything special at all and that it's usually above 200km. Second stages usually tend to stay for months in GTO even with perigees as low as that altitude, it's not that complex to understand I guess.
IIRC the first Block 5 launch used a Block 4 flight profile for S2 (not utilizing the extra thrust). Presumably this launch will be using full rated thrust on both S1and S2 to get this bird as close to a normal GTO as possible. Will be interesting to compare!
SpaceX has still not publicly made the webcast link available, it is a private youtube link.
SpaceX has still not publicly made the webcast link available, it is a private youtube link.
Is anyone going to share it?
Booster is back :)
Interesting. The calls were very clear over the loop that the F9 had landed safely, yet webcast host seemed very uncertain if a landing had occurred.
First stage cutoff was at 8170 km/hr = 2270 m/s.
This is exactly what we've seen on previous GTO with recovery missions. So no big performance boost for block 5.
Little bit of tumble on the payload?
I don’t remember seeing that much tumble on previous launches. I doubt it’s a concern but is different.
That was quite a long trail of green as S2 lit up. I guess I hadn't noticed that before. I didn't see a jellyfish plume on S2 this time, perhaps it needs light reflecting off it from the sun or moon.
Great launch.
That was quite a long trail of green as S2 lit up. I guess I hadn't noticed that before. I didn't see a jellyfish plume on S2 this time, perhaps it needs light reflecting off it from the sun or moon.
Great launch.
You'll only see a jellyfish if the launch is just before dawn or after sunset. The 2nd stage plume needs to be illuminated by the sun to create that effect, and in this case the 2nd stage did not get into sunlight until a couple of minutes after engine cutoff.
Looked very sub-synchronous. Telemetry froze for a while, but when it resumed (at 30:43) it showed 32835 km/hr = 9120 m/s. Add in the 402 m/s from Earth's rotation, to get 9522 m/s. That's about a 14000 km apogee (assuming no inclination reduction), and another 600 m/s to go to get to a nominal GTO. So GEO - 2400 m/s.That's what I'm getting too, something like a 250 x 14,000 km (or less) orbit. I think we expected subsynchronous, but I wonder about the "very" part.
First stage cutoff was at 8170 km/hr = 2270 m/s.
This is exactly what we've seen on previous GTO with recovery missions. So no big performance boost for block 5.
Am I misremembering, or is MECO normally at around 2.24, whereas today it was about 10 seconds later at 2.34? Is there any significance to this, as in a correlation to increased peformance, or is this an optional cutoff point based on mission profile?
Looked very sub-synchronous. Telemetry froze for a while, but when it resumed (at 30:43) it showed 32835 km/hr = 9120 m/s. Add in the 402 m/s from Earth's rotation, to get 9522 m/s. That's about a 14000 km apogee (assuming no inclination reduction), and another 600 m/s to go to get to a nominal GTO. So GEO - 2400 m/s.That's what I'm getting too, something like a 250 x 14,000 km (or less) orbit. I think we expected subsynchronous, but I wonder about the "very" part.
- Ed Kyle
That was quite a long trail of green as S2 lit up. I guess I hadn't noticed that before. I didn't see a jellyfish plume on S2 this time, perhaps it needs light reflecting off it from the sun or moon.
Great launch.
You'll only see a jellyfish if the launch is just before dawn or after sunset. The 2nd stage plume needs to be illuminated by the sun to create that effect, and in this case the 2nd stage did not get into sunlight until a couple of minutes after engine cutoff.
Yea, too far away by then for me to see it with my binoculars.
Looked very sub-synchronous. Telemetry froze for a while, but when it resumed (at 30:43) it showed 32835 km/hr = 9120 m/s. Add in the 402 m/s from Earth's rotation, to get 9522 m/s. That's about a 14000 km apogee (assuming no inclination reduction), and another 600 m/s to go to get to a nominal GTO. So GEO - 2400 m/s.The variable we won't know until we get TLE's is the inclination. There could be a bunch of inclination reduction in that burn as well that won't show up in the final velocity.
That was quite a long trail of green as S2 lit up. I guess I hadn't noticed that before. I didn't see a jellyfish plume on S2 this time, perhaps it needs light reflecting off it from the sun or moon.
Great launch.
You'll only see a jellyfish if the launch is just before dawn or after sunset. The 2nd stage plume needs to be illuminated by the sun to create that effect, and in this case the 2nd stage did not get into sunlight until a couple of minutes after engine cutoff.
Yea, too far away by then for me to see it with my binoculars.
Binoculars would have made no difference :-), the stage was way over the horizon and practically over Africa before it hit sunlight.
Looked very sub-synchronous. Telemetry froze for a while, but when it resumed (at 30:43) it showed 32835 km/hr = 9120 m/s. Add in the 402 m/s from Earth's rotation, to get 9522 m/s. That's about a 14000 km apogee (assuming no inclination reduction), and another 600 m/s to go to get to a nominal GTO. So GEO - 2400 m/s.The variable we won't know until we get TLE's is the inclination. There could be a bunch of inclination reduction in that burn as well that won't show up in the final velocity.
Can you provide the source? I remember she had said that, but forgot whenSpaceflight Now is reporting this sat's mass is 7075kg, the heaviest GTO sat ever. Link to article: https://spaceflightnow.com/2018/07/21/record-setting-commercial-satellite-awaits-blastoff-from-cape-canaveral/
At last the mythical 7-ton sat Gwynne mentioned shows up :D
Looked very sub-synchronous. Telemetry froze for a while, but when it resumed (at 30:43) it showed 32835 km/hr = 9120 m/s. Add in the 402 m/s from Earth's rotation, to get 9522 m/s. That's about a 14000 km apogee (assuming no inclination reduction), and another 600 m/s to go to get to a nominal GTO. So GEO - 2400 m/s.The variable we won't know until we get TLE's is the inclination. There could be a bunch of inclination reduction in that burn as well that won't show up in the final velocity.
Unless you have another look at worldmap with the trajectory on the livestream. You'll see it shifting north from crossing Lake Bangweulu to crossing above Lake Mweru - or roughly half the north-south extend of Lake Malawi. Which is a difference of about 300km at a distance of about 3000km from the equator. So it lost on the order of 6 degrees of inclination.
So ths reduces the delta-v required for plane change to 245 m/s, saves 75m/s and makes it approximately a GEO -2325m/s trajectory. [Goof corrected.]
Were the fairings halves recovered?
And now we see TLEs showing 243 x 17,863 km x 27 deg for 7,075 kg Telestar 19V. We missed the maximum velocity at engine cutoff due to the data dropout (screen freeze), which led us to our lower initial apogee estimate.Looked very sub-synchronous. Telemetry froze for a while, but when it resumed (at 30:43) it showed 32835 km/hr = 9120 m/s. Add in the 402 m/s from Earth's rotation, to get 9522 m/s. That's about a 14000 km apogee (assuming no inclination reduction), and another 600 m/s to go to get to a nominal GTO. So GEO - 2400 m/s.That's what I'm getting too, something like a 250 x 14,000 km (or less) orbit. I think we expected subsynchronous, but I wonder about the "very" part.
- Ed Kyle
HISPASAT 30W-6 (with its smaller mass of 6,092 kg) was launched by Falcon 9 Block 4 to 184 x 22,261 km, 26.97°
And now we see TLEs showing 243 x 17,863 km x 27 deg for 7,075 kg Telestar 19V. We missed the maximum velocity at engine cutoff due to the data dropout (screen freeze), which led us to our lower initial apogee estimate.Looked very sub-synchronous. Telemetry froze for a while, but when it resumed (at 30:43) it showed 32835 km/hr = 9120 m/s. Add in the 402 m/s from Earth's rotation, to get 9522 m/s. That's about a 14000 km apogee (assuming no inclination reduction), and another 600 m/s to go to get to a nominal GTO. So GEO - 2400 m/s.That's what I'm getting too, something like a 250 x 14,000 km (or less) orbit. I think we expected subsynchronous, but I wonder about the "very" part.
- Ed Kyle
HISPASAT 30W-6 (with its smaller mass of 6,092 kg) was launched by Falcon 9 Block 4 to 184 x 22,261 km, 26.97°
They had planned to attempt OSCILY landing for the Hispasat booster, but sea states prevented an attempt.
As I see it, VA-189/TerraStar 1 still holds the record for GTO mass (6,910 kg to 250 x 35,786 km x 6 deg), since Telestar 19V went subsynchronous.
- Ed Kyle
2018-059A/43562 (243 km x 17863 km x 27.00°) has a delta v to GTO of 2064.5751 m/s or it is in GTO-2065What parameters did you use? I get 2277 m/s using that approach (which seems to agree with this (https://gtocalc.github.io/) online implementation)...? BTW, doing a third of a degree of the inclination change in the first apogee raising burn saves ~4 m/s.
2018-059B/43563 (242 km x 17860 km x 27.00°) has a delta v to GTO of 2064.7341 m/s or it is in GTO-2065
according to my C/C++ program based on this (https://forum.nasaspaceflight.com/index.php?topic=36954.0).
2018-059A/43562 (243 km x 17863 km x 27.00°) has a delta v to GTO of 2064.5751 m/s or it is in GTO-2065What parameters did you use? I get 2277 m/s using that approach (which seems to agree with this (https://gtocalc.github.io/) online implementation)...? BTW, doing a third of a degree of the inclination change in the first apogee raising burn saves ~4 m/s.
2018-059B/43563 (242 km x 17860 km x 27.00°) has a delta v to GTO of 2064.7341 m/s or it is in GTO-2065
according to my C/C++ program based on this (https://forum.nasaspaceflight.com/index.php?topic=36954.0).
| #include <iostream> #include <iomanip> #include <cmath> using namespace std; int main() { int stay; do { stay=0; double perigee, apogee, inclination; cout << "Enter perigee in km, apogee in km, inclination in degrees." << endl; cin >> perigee >> apogee >> inclination; cout << setprecision(4) << fixed << "Perigee: " << perigee << " km" << endl << "Apogee: " << apogee << " km" << endl; double sma; sma = ((perigee + apogee) / 2) + 6371; //semi-minor axis, 6371 is Earth radius in km cout << setprecision(4) << fixed << "Semi-major axis: " << sma << " km" << endl; double const MU = 3.986005e14; double vp, va; vp = sqrt((MU * (apogee + 6371) * 1000) / ((perigee + 6371) * sma * 1e6)); va = sqrt((MU * (perigee + 6371) * 1000) / ((apogee + 6371) * sma * 1e6)); cout << setprecision(4) << fixed << "Speed at perigee: " << vp << " m/s" << endl << "Speed at apogee: " << va << " m/s" << endl; double rpd = 8681663.653 / pow(sma, 3 / 2); //revolutions per day cout << setprecision(4) << fixed << "Revolutions per day: " << rpd << endl << "Days per revolution: " << 1 / rpd << endl; double sync = 35786; sma = (sync + apogee) / 2 + 6371; perigee = sync; double nvp, nva; nvp = sqrt((MU * (apogee + 6371) * 1000) / ((perigee + 6371) * sma * 1e6)); nva = sqrt((MU * (perigee + 6371) * 1000) / ((apogee + 6371) * sma * 1e6)); cout << setprecision(4) << fixed << "Speed at perigee: " << nvp << " m/s" << endl << "Speed at apogee: " << nva << " m/s" << endl; double cross, along, need_along, dv_top, dv_bot, total; double const GEO_V = 3075; cross = va * sin((inclination / 180) * M_PI); along = va * cos((inclination / 180) * M_PI); cout << setprecision(4) << fixed << "Cross v at apogee: " << cross << " m/s" << endl << "Along track: " << along << " m/s" << endl; need_along = nva - along; dv_top = sqrt(pow(cross, 2) + pow(need_along, 2)); cout << setprecision(4) << fixed << "Delta-v at top: " << dv_top << endl; dv_bot = nvp - GEO_V; cout << setprecision(4) << fixed << "Delta-v at bot: " << dv_bot << endl; total = dv_top + dv_bot; cout << setprecision(4) << fixed << "Delta-v (total): " << total << endl; cout << "Enter 1 to restart or any key to close." << endl; cin >> stay; }while(stay==1); return 0; } |
2018-059A/43562 (243 km x 17863 km x 27.00°) has a delta v to GTO of 2064.5751 m/s or it is in GTO-2065What parameters did you use? I get 2277 m/s using that approach (which seems to agree with this (https://gtocalc.github.io/) online implementation)...? BTW, doing a third of a degree of the inclination change in the first apogee raising burn saves ~4 m/s.
2018-059B/43563 (242 km x 17860 km x 27.00°) has a delta v to GTO of 2064.7341 m/s or it is in GTO-2065
according to my C/C++ program based on this (https://forum.nasaspaceflight.com/index.php?topic=36954.0).
I used the TLE data along with the program written by LouScheffer. I literally "translated" that program.
This is the program, it should compile with GCC using C++11:
...
No word yet on T19V health - should have had something by now ? I may have missed it - I just don't see any news on health
Running solasto's implementation doesn't give any errors but I think it spits out a perigee speed that is lower than the apogee speed after the first burn and a corresponding negative delta v. This could be taken as a warning ;)2018-059A/43562 (243 km x 17863 km x 27.00°) has a delta v to GTO of 2064.5751 m/s or it is in GTO-2065What parameters did you use? I get 2277 m/s using that approach (which seems to agree with this (https://gtocalc.github.io/) online implementation)...? BTW, doing a third of a degree of the inclination change in the first apogee raising burn saves ~4 m/s.
2018-059B/43563 (242 km x 17860 km x 27.00°) has a delta v to GTO of 2064.7341 m/s or it is in GTO-2065
according to my C/C++ program based on this (https://forum.nasaspaceflight.com/index.php?topic=36954.0).
I used the TLE data along with the program written by LouScheffer. I literally "translated" that program.
This is the program, it should compile with GCC using C++11:
...
Unfortunately, that program is only correct for synchronous or greater. It does not account for the perigee burn to raise the apogee, gets the wrong sign for circularization if the apogee is below GEO, and will do the inclination reduction at the wrong burn if sub-sync. So the numbers from this program will be wrong for the sub-sync case, which this is. Sorry, it should check for that and either do it right, or at least give a message, rather than silently doing it wrong.
Running solasto's implementation doesn't give any errors but I think it spits out a perigee speed that is lower than the apogee speed after the first burn and a corresponding negative delta v. This could be taken as a warning ;)2018-059A/43562 (243 km x 17863 km x 27.00°) has a delta v to GTO of 2064.5751 m/s or it is in GTO-2065What parameters did you use? I get 2277 m/s using that approach (which seems to agree with this (https://gtocalc.github.io/) online implementation)...? BTW, doing a third of a degree of the inclination change in the first apogee raising burn saves ~4 m/s.
2018-059B/43563 (242 km x 17860 km x 27.00°) has a delta v to GTO of 2064.7341 m/s or it is in GTO-2065
according to my C/C++ program based on this (https://forum.nasaspaceflight.com/index.php?topic=36954.0).
I used the TLE data along with the program written by LouScheffer. I literally "translated" that program.
This is the program, it should compile with GCC using C++11:
...
Unfortunately, that program is only correct for synchronous or greater. It does not account for the perigee burn to raise the apogee, gets the wrong sign for circularization if the apogee is below GEO, and will do the inclination reduction at the wrong burn if sub-sync. So the numbers from this program will be wrong for the sub-sync case, which this is. Sorry, it should check for that and either do it right, or at least give a message, rather than silently doing it wrong.
Since TerreStar 1 was the previous record holder for largest commercial spacecraft to GEO and launched by Ariane Space to a geosynchronous transfer orbit, I am curious how the delta v compares to Telstar 19. Does anyone know the delta v for TerreStar 1?Terrestar 1 was a standard GTO from Kourou, so GEO-1500 m/s.
The extra payload mass is only a tiny fraction of the vehicle mass at staging.First stage cutoff was at 8170 km/hr = 2270 m/s.
This is exactly what we've seen on previous GTO with recovery missions. So no big performance boost for block 5.
You don't consider the fact that they did this with a payload in excess of SEVEN TONS, as significant?
GTO-2275 @7075kg ...
I decided to rewrite the code from scratch to fix the issue and to write it in good C++, but I decided to also add a feature that finds the most efficient way to GEO. So now it will also scrub some of the inclination at perigee, just as much to reduce the total delta v budget.
Here is the github repository: https://github.com/AleLovesio/delta-v-to-GTO (The source files are in the source folder)
I also uploaded the files here as txts since the cpp and h extensions are not allowed even if in the end they are just text files.
Since TerreStar 1 was the previous record holder for largest commercial spacecraft to GEO and launched by Ariane Space to a geosynchronous transfer orbit, I am curious how the delta v compares to Telstar 19. Does anyone know the delta v for TerreStar 1?Terrestar 1 was a standard GTO from Kourou, so GEO-1500 m/s.
Since TerreStar 1 was the previous record holder for largest commercial spacecraft to GEO and launched by Ariane Space to a geosynchronous transfer orbit, I am curious how the delta v compares to Telstar 19. Does anyone know the delta v for TerreStar 1?Terrestar 1 was a standard GTO from Kourou, so GEO-1500 m/s.
Thanks. I thought it would be interesting to compare Terrestar 1 to Telstar 19 since they have equivalent mass and SpaceX landed the first stage. A recurring argument recently is that SpaceX is wasting fuel on reuse versus getting the satellite at or nearer to GEO.
A recurring argument recently is that SpaceX is wasting fuel on reuse versus getting the satellite at or nearer to GEO.Fuel is cheap. Spacecraft are expensive.
And rockets are expensiveA recurring argument recently is that SpaceX is wasting fuel on reuse versus getting the satellite at or nearer to GEO.Fuel is cheap. Spacecraft are expensive.
A recurring argument recently is that SpaceX is wasting fuel on reuse versus getting the satellite at or nearer to GEO.
The customer will calculateSince TerreStar 1 was the previous record holder for largest commercial spacecraft to GEO and launched by Ariane Space to a geosynchronous transfer orbit, I am curious how the delta v compares to Telstar 19. Does anyone know the delta v for TerreStar 1?Terrestar 1 was a standard GTO from Kourou, so GEO-1500 m/s.
Thanks. I thought it would be interesting to compare Terrestar 1 to Telstar 19 since they have equivalent mass and SpaceX landed the first stage. A recurring argument recently is that SpaceX is wasting fuel on reuse versus getting the satellite at or nearer to GEO.
I decided to rewrite the code from scratch to fix the issue and to write it in good C++, but I decided to also add a feature that finds the most efficient way to GEO. So now it will also scrub some of the inclination at perigee, just as much to reduce the total delta v budget.
Here is the github repository: https://github.com/AleLovesio/delta-v-to-GTO (The source files are in the source folder)
I also uploaded the files here as txts since the cpp and h extensions are not allowed even if in the end they are just text files.
Could you compare with JCSAT-16? It's a close match telemetry-wise, but the final orbit from F9 was 184 km × 35,912 km × 20.85°.
| Current Orbit: 184.0000 km x 35912.0000 km x 20.8500 degrees; Apogee Speed: 1590.7738 m/s; Perigee Speed: 10261.2798 m/s; delta v to this orbit: 0.0000 Super-sync transfer. First maneuver: Perigee changed to 35786km Inclination changed to 0.0146 degrees Current Orbit: 35786.0000 km x 35912.0000 km x 0.0146 degrees; Apogee Speed: 3068.0452 m/s; Perigee Speed: 3077.2151 m/s; delta v to this orbit: 1679.4790 Second maneuver: Apogee changed to 35786km Inclination changed to 0.0146 degrees Current Orbit: 35786.0000 km x 35786.0000 km x 0.0000 degrees; Apogee Speed: 3074.9218 m/s; Perigee Speed: 3074.9218 m/s; delta v to this orbit: 1681.9025 Total delta v to GEO: 1681.9025 m/s |
A recurring argument recently is that SpaceX is wasting fuel on reuse versus getting the satellite at or nearer to GEO.
Yes. Another way to say it is that the satellite's propulsion system amounts to a thrid stage of the rocket. Drop the weight of the second stage empty tank and engine and keep going.A recurring argument recently is that SpaceX is wasting fuel on reuse versus getting the satellite at or nearer to GEO.
Just a note on wasting fuel: if the satellite bus is large enough to hold a sizeable amount of fuel for orbit raising (understood the be about 3mt for Telstar 19V), it is way more efficient due to less overall mass to let the satellite raise itself to the final orbit than have the second stage do the job partially. It is just a tradeoff between the reduced cost of a reusable launch into a low-energy orbit or paying more for an expendable launch and gaining some additional years of in-orbit operations.
Could you compare with JCSAT-16? It's a close match telemetry-wise, but the final orbit from F9 was 184 km × 35,912 km × 20.85°.
You are looking at it in vacuum. Even a tiny bit of gas inside the blanket would "puff it up". Also once it is "puffed up", there is nothing to make it collapse again. Even if all that gas just escapes from under the blanket, it stays puffed up unless something pushes it from the outside.
You are looking at it in vacuum. Even a tiny bit of gas inside the blanket would "puff it up". Also once it is "puffed up", there is nothing to make it collapse again. Even if all that gas just escapes from under the blanket, it stays puffed up unless something pushes it from the outside.
Anybody noticed that one of the LOX tank panels is significantly darker?
It seems they're going to manually retract the legs with cables running down from the lifting cap to the legsPersonally I find this highly suspect. It's been common practice for SpaceX to run guy wires from cap to automatic tensioners on the ground to keep the rocket stable. To me these images look like they are rigging those lines. I'd be happy to be proven wrong however...
This was the rumor that was going on since yesterday about the leg retraction:
https://twitter.com/MatthewCable6/status/1022285498612690944 (https://twitter.com/MatthewCable6/status/1022285498612690944)
Now it seems real:
https://twitter.com/ThAerospaceGeek/status/1022507131331911680 (https://twitter.com/ThAerospaceGeek/status/1022507131331911680)
Edit: Another picture in this tweet (I don't know how to add photos here) of the cables being lowered down from the cap to the bottom
https://twitter.com/ken_kremer/status/1022514478355763200 (https://twitter.com/ken_kremer/status/1022514478355763200)
It seems they're going to manually retract the legs with cables running down from the lifting cap to the legsPersonally I find this highly suspect. It's been common practice for SpaceX to run guy wires from cap to automatic tensioners on the ground to keep the rocket stable. To me these images look like they are rigging those lines. I'd be happy to be proven wrong however...
This was the rumor that was going on since yesterday about the leg retraction:
https://twitter.com/MatthewCable6/status/1022285498612690944 (https://twitter.com/MatthewCable6/status/1022285498612690944)
Now it seems real:
https://twitter.com/ThAerospaceGeek/status/1022507131331911680 (https://twitter.com/ThAerospaceGeek/status/1022507131331911680)
Edit: Another picture in this tweet (I don't know how to add photos here) of the cables being lowered down from the cap to the bottom
https://twitter.com/ken_kremer/status/1022514478355763200 (https://twitter.com/ken_kremer/status/1022514478355763200)
Were the fairings halves recovered?
If you mean were they caught by a ship with the net on it? No. If the fairings had the recovery hardware installed, they may get picked up from the ocean surface. But SpaceX doesn't currently have a fairing catching ship on the east coast. Their only one Mr. Steven, which operates out of Los Angeles and attempts catching fairing halves from launches out of VAFB. Next attempt will be on the upcoming Iridium 7 launch.
just saw the CNN story it was in my view not that negative I guess mileage might varyWere the fairings halves recovered?
If you mean were they caught by a ship with the net on it? No. If the fairings had the recovery hardware installed, they may get picked up from the ocean surface. But SpaceX doesn't currently have a fairing catching ship on the east coast. Their only one Mr. Steven, which operates out of Los Angeles and attempts catching fairing halves from launches out of VAFB. Next attempt will be on the upcoming Iridium 7 launch.
This is an actual headline on CNN:
SpaceX loses multi million dollar fairing
The headline doesn't mention that the launch and primary mission were successful, nor does it mention that SpaceX landed the first stage in the worst conditions ever. Nope, the headline is about how SpaceX FAILED to catch the fairing.
Wow, are we disappointed in SpaceX for failing to do something that has NEVER been done by anyone before. :o
just saw the CNN story it was in my view not that negative I guess mileage might varyWere the fairings halves recovered?
If you mean were they caught by a ship with the net on it? No. If the fairings had the recovery hardware installed, they may get picked up from the ocean surface. But SpaceX doesn't currently have a fairing catching ship on the east coast. Their only one Mr. Steven, which operates out of Los Angeles and attempts catching fairing halves from launches out of VAFB. Next attempt will be on the upcoming Iridium 7 launch.
This is an actual headline on CNN:
SpaceX loses multi million dollar fairing
The headline doesn't mention that the launch and primary mission were successful, nor does it mention that SpaceX landed the first stage in the worst conditions ever. Nope, the headline is about how SpaceX FAILED to catch the fairing.
Wow, are we disappointed in SpaceX for failing to do something that has NEVER been done by anyone before. :o
The CNN coverage is about the Iridium-7 launch, not Telstar 19V. Shouldn't this discussion be in that thread?Were the fairings halves recovered?
If you mean were they caught by a ship with the net on it? No. If the fairings had the recovery hardware installed, they may get picked up from the ocean surface. But SpaceX doesn't currently have a fairing catching ship on the east coast. Their only one Mr. Steven, which operates out of Los Angeles and attempts catching fairing halves from launches out of VAFB. Next attempt will be on the upcoming Iridium 7 launch.
This is an actual headline on CNN:
SpaceX loses multi million dollar fairing
The headline doesn't mention that the launch and primary mission were successful, nor does it mention that SpaceX landed the first stage in the worst conditions ever. Nope, the headline is about how SpaceX FAILED to catch the fairing.
Wow, are we disappointed in SpaceX for failing to do something that has NEVER been done by anyone before. :o
Midday update: booster legs still attached, some venting seen from a nearby truck, and loud venting noises heard, something is happening......
https://mobile.twitter.com/ThAerospaceGeek/status/1022890678571941888
https://mobile.twitter.com/ThAerospaceGeek/status/1022869961021292545
SpaceX - First Leg Retract - Booster Lift 07-27-2018
USLaunchReport
https://www.youtube.com/watch?v=L2tc2r3jwhE (https://www.youtube.com/watch?v=L2tc2r3jwhE)
Welp, the raised leg was lowered and all 4 leg pistons have been removed, the leg raising was just a test it appears......or they had issues latching the leg. Remains to be confirmed.
https://mobile.twitter.com/ken_kremer/status/1023610742237552643
Anyone knows where they needed the liquid nitrogen for? The tank can clearly be seen in the USLaunchReport video and in the pictures up thread.
Anyone knows where they needed the liquid nitrogen for? The tank can clearly be seen in the USLaunchReport video and in the pictures up thread.
Anyone knows where they needed the liquid nitrogen for? The tank can clearly be seen in the USLaunchReport video and in the pictures up thread.
My guess is to provide gaseous N2 for pressurizing the opposite side of the cylinders to cause the legs to retract themselves.
I guess I am used to tractor and truck hydraulics that always have fittings on both sides of the piston. Is it that much harder to make a piston and cylinder to do both ways?
I believe I heard something about a temporary slot for testing before moving into it's operational slot.TELSTAR 19V 2018-059A 1387.88min 0.37deg 35706km 33969km
That was a big burn! Now only ~40m/s left to get to GEO, then moving to it's orbital slot.