I've been watching and waiting for this day since first hearing that it was a double launch day last week. We've known something like that was possible, since ULA announced the Vulcan Return to Flight was going to be Friday the 13th back a couple of weeks ago, but the two big launches on the same day wasn't known back then.
The Launch Schedule from NextSpaceflight.
The launch times are in Eastern Standard Time.
The Vulcan mission is important to United Launch Alliance and to the Amazon Leo constellation of satellites it's getting into orbit. The Vulcan has been grounded since the flight of the Vulcan last February on what was the fourth Vulcan mission due to problems with the nozzles on the solid rocket boosters strapped on the sides of the booster. The nozzles broke on two of the first four Vulcan launches. This version is called the VC6L and has six of those solid rocket boosters. The VC6L is the most powerful configuration of the Vulcan rocket thanks to those six solid rocket boosters, and a low-Earth orbit-optimized Centaur V upper stage.
The investigation identified three credible causes of the nozzle liberation issue experienced on USSF-87, and NGC applied fixes to mitigate each. The changes to the booster included design and manufacturing fixes, and these will be tested on LV-01. NGC and ULA will gather data during this flight to help improve the nozzle.
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If the LV-01 flight goes well, ULA is prepared to ramp up its Vulcan flight cadence, with the LV-02 mission for Amazon Leo already being processed in VIF-G. The Space Force and NASA are monitoring the flight, as national security payloads and the Boeing Starliner crewed spacecraft are planned to launch on Vulcan in the future.
As LV-01 is important to ULA and Amazon, Starship's Flight 15 is important to SpaceX. This is the first Starship mission planned to return both the SuperHeavy booster and the ship to the launch site. Other boosters have been captured with the Mechazilla arms before, but only for Version 1 boosters, never a V3. Unlike the boosters, a Starship has never been recovered with the tower's arms. If successful, this will mark the first full recovery of an orbital launch system and a breakthrough moment in making Starship a reliable, rapidly reusable rocket.
Starship’s initial return to launch site mission is expected to orbit the Earth at an altitude of ~275 km and complete approximately 14 orbits around the planet over the course of a more than 22-hour flight. Similar to Starship’s first orbital mission, the flight profile has been designed with the opportunity to insert into a passively safe suborbital trajectory or safely deorbit at multiple pre-determined areas over the ocean after raising to an orbital altitude.
While these captures of the booster and ship are what many of us will be watching for, the real money-making aspect of the mission will be releasing 26 of the much bigger and more capable V3 Starlink satellites. Each Starlink V3 satellite will add 1 Terabit of capacity to the constellation, with all 26 satellites equaling ~10 Starlink V2 Mini launches on the Falcon 9.
Screen Capture of the SpaceX website with a video about the upcoming mission. Image credit: SpaceX
EDIT 11/13 10:00 AM to add: As of 9:50AM, word got out that the ULA Vulcan launch has been scrubbed for the day. Nextspaceflight.com shows re-schedule for Saturday at 12:32PM EST.
~275 km, or roughly 171 sm seems quite low. Since this mission is to insert satellites into orbit, at what final altitude will the sats fly and how will they get there?
ReplyDeleteStarlink has always been based on being in relatively low orbits to minimize internet latency for those connected through it. While we don't think about it much, they always have deployed the satellite just barely in orbit. That gave the controllers time while they were up in that initial RLEO (Really Low Earth Orbit) to double check the sats and if a particular one or two wasn't responding properly, they'd have those sats reenter on their own. Once they checked out, they would use relatively small thrusters to elevate them up to their spot in the constellation.
DeleteI remember seeing a thing about them raising a lot of orbits because the expansions of the atmosphere with solar "events" were causing too many to reenter too soon. I'm not sure what the current number is, but a quick search says 480 km.
275 km is the release altitude. The satellites use their own power upto the 350 km-ish altitude for V3's. The lower release altitude is in case anything goes wrong, everything will just fall out of orbit. If released in the operating orbit and something goes wrong, it could adversely affect everything already up there. The 350 km altitude is low to enable direct to phone communications.
Delete"The launch times are in Eastern Standard Time. "
ReplyDeleteI am on the West Coast and the times shown here are in Pacific Standard Time. It looks like the NextSpaceFlight site gives launches in one's local time.
Not a big deal but something to be aware of.
Thanks for that. I meant that the times displayed in the screen capture were EST, but didn't say that. I've been wondering about whether they displayed the time zone your computer says you're in - or something like that.
DeleteLooks like LV-01 has slipped to tomorrow.
ReplyDelete