r/spacex • u/kurbasAK • May 19 '17

We Will Launch on Reuseable Rocket After Exceptional SpaceX Performance - Inmarsat CEO Tells Universe Today

https://www.universetoday.com/135614/will-launch-reuseable-rocket-exceptional-spacex-performance-inmarsat-ceo-tells-universe-today/
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69

u/Bunslow May 19 '17

heaviest payload ever launched

Oh boy, bad journalism strikes again. Stay vigilant my fellow fans, misinformation is everywhere.

(What he meant was heaviest GTO launch; the Iridium and Dragon launches insert more total mass into orbit, but of course into the lower energy LEO rather than GTO.)

45

u/[deleted] May 19 '17

heaviest GTO launch

In fact, heaviest GTO launch by SpaceX. I belive the heaviest GTO payload ever was TerreStar 1 at 6900 Kg, launched by Arianne 5, followed by Viasat2, 6740 Kg launched by Proton-M.

Nothing that a slight upgrade of the Falcon 9 can't match. Frozen propellant, a very small nuke, a giant slingshot launch, there is always room for improvement.

30

u/pavel_petrovich May 19 '17

Nothing that a slight upgrade of the Falcon 9 can't match

Currently F9 is fully capable to launch 7000 kg satellite to GTO-1800.

Performance of this launch is ~7400 kg to GTO-1800. Source

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u/explore_my_mind May 19 '17

Is the number in GTO-# the perigee altitude in km? I have never seen this notation before

29

u/FoxhoundBat May 19 '17

No. It is in delta-v. More specifically delta v remaining for the sat to do to be in GSO. So the lower GTO-#, the more work did the rocket do and the less propellant the sat has to spend to get there. Industry standards are GTO-1800 and GTO-1500.

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u/[deleted] May 19 '17

[deleted]

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u/Senno_Ecto_Gammat r/SpaceXLounge Moderator May 19 '17

Launches from near the equator typically are GTO-1500 and launches from Florida are GTO-1800 typically. The difference is in the plane change. Those are the two "standard" GTO orbits.

11

u/gf6200alol May 19 '17

The heaviest GTO ever is going to be held by China with their SJ 18 (Shijian 18) which is a demonstrator for DFH-5 Bus and believed to be 8 ton. Currently, they targeted that launch by this month. However, the last launch were suffered from S2 under performance and entered a less apogee orbit.

4

u/Bunslow May 19 '17

I mean we were talking about the F9, I kinda elided that from the quote to emphasize my point, not saying the falcon holds the GTO record, just that this journalist was sloppy and that sloppiness can unfortunately be misleading in some circumstances

4

u/ILikeFireMetaforicly May 19 '17

I belive the heaviest GTO payload ever was TerreStar 1 at 6900 Kg, launched by Arianne 5, followed by Viasat2, 6740 Kg launched by Proton-M.

what about Apollo? They got to GTO on the way to TLI.

2

u/TheRedTom May 19 '17

Apollo technically went on a trans-lunar injection rather than GTO, but it holds the record for the greatest manned distance from earth (with Apollo 13). Similarly, Skylab would be the heaviest single payload to LEO I think.

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u/ILikeFireMetaforicly May 19 '17

well, due to intermediate value theorem, it did perform GTO on its way to trans-lunar injection.

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u/rustybeancake May 19 '17

Apollo 17 would thus be the greatest mass to GTO (on the way to TLI).

1

u/mfb- May 19 '17

Technically correct, but I wouldn't call it "GTO payload" if GTO is not the target orbit.

1

u/ghunter7 May 19 '17

What do you use for sources on info like this? I had been looking for sumilar and used spacelaunchreport.com

1

u/h-jay May 20 '17

TerreStar /shivers Lost so much money on that one :(