The ULA mission booklet is available at:https://www.ulalaunch.com/docs/default-source/launch-booklets/divh_parkersolarprobe_mob.pdfIt shows a C3 of 153.79 .
Quote from: Newton_V on 08/02/2018 03:41 pmQuote from: edkyle99 on 08/02/2018 02:33 amWhen the Delta 4 second stage completes its second burn, will Parker Solar Probe/Star 48BV be heliocentric, or will it take the Star 48BV burn to put PSP into actual solar orbit? In other words, what orbit will the Delta stage be in after its second burn?I seem to recall C3 was > 50.This seems reasonable. The rough calculation above yields LEO+5.3 km/sec. Using this chart of C3 vs dV from LEO gives a C3 slightly over 50 km2/sec2 for the second stage, as opposed to 154 km2/sec2 for PSP itself.Also, PSP plus the Star 48 mass is about 2700 kg together. Then this plot of Delta IV Heavy performance shows about 55 km2/sec2. So all is consistent.EDIT: Added another way to get the same conclusion.
Quote from: edkyle99 on 08/02/2018 02:33 amWhen the Delta 4 second stage completes its second burn, will Parker Solar Probe/Star 48BV be heliocentric, or will it take the Star 48BV burn to put PSP into actual solar orbit? In other words, what orbit will the Delta stage be in after its second burn?I seem to recall C3 was > 50.
When the Delta 4 second stage completes its second burn, will Parker Solar Probe/Star 48BV be heliocentric, or will it take the Star 48BV burn to put PSP into actual solar orbit? In other words, what orbit will the Delta stage be in after its second burn?
I'm not sure if it's pertinent here, but I've been accepted to the NASA Social for the Parker Solar Probe launch. Is there anything I should look out for? If I get the chance to ask any questions, are there any questions I should ask? I can't think of one of my own so far.They just yesterday sent us the finalized schedule, as the slip to the 11th threw their scheduling off.
...Last civil launch of the most powerful rocket in service on the planet, no less!...
Quote from: eeergo on 08/03/2018 04:43 pm...Last civil launch of the most powerful rocket in service on the planet, no less!...Former most powerful rocket.
Quote from: AncientU on 08/03/2018 05:14 pmQuote from: eeergo on 08/03/2018 04:43 pm...Last civil launch of the most powerful rocket in service on the planet, no less!...Former most powerful rocket.Wrong, this one is. FH can't meet the C3 capabilities
Can someone explain why on the Delta IV Heavy the starboard booster ignites 2 seconds after the centre/port boosters?Screen shot from yesterdays ULA Mission PDF.
Quote from: Grandpa to Two on 08/03/2018 09:48 pmCan someone explain why on the Delta IV Heavy the starboard booster ignites 2 seconds after the centre/port boosters?Screen shot from yesterdays ULA Mission PDF.The main reason why the starboard side core ignites before the other two is to reduce the hydrogen fireball that occurs when LH2 rises upward and burns the orange insulation due to the ROFI sparks igniting the fuel.
Yeah, I remember seeing that on one of the docs I was reading recently, and it caught me by surprise. I thought it would've been outer/center, or center/outer, like falcon heavy was. But it's just more of Delta IV being a wonderful monster of a rocket that sets itself on fire.
Quote from: Lupi on 08/03/2018 10:47 pmYeah, I remember seeing that on one of the docs I was reading recently, and it caught me by surprise. I thought it would've been outer/center, or center/outer, like falcon heavy was. But it's just more of Delta IV being a wonderful monster of a rocket that sets itself on fire.Drop the adjective "wonderful" and you'll capture my feelings about this "monster"! This is my fourth mission of the year as prime NASA Electrical, and this "monster" is putting the finishing touches on wearing me down.And I've still got Pegasus/ICON to finish off! I'm so glad I'll have all of next year to rest up!
<snip>There are no LSP launches next year.<snip>
Drop the adjective "wonderful" and you'll capture my feelings about this "monster"! This is my fourth mission of the year as prime NASA Electrical, and this "monster" is putting the finishing touches on wearing me down.And I've still got Pegasus/ICON to finish off! I'm so glad I'll have all of next year to rest up!
Thinking of Jim, have you been working this mission?
Quote from: Jim on 08/03/2018 05:35 pmQuote from: AncientU on 08/03/2018 05:14 pmQuote from: eeergo on 08/03/2018 04:43 pm...Last civil launch of the most powerful rocket in service on the planet, no less!...Former most powerful rocket.Wrong, this one is. FH can't meet the C3 capabilitiesJim is this due to the fact that the Delta IV Heavy has a third stage and Falcon Heavy doesn’t?