Also, webcast would confirm if this is the first flight of the new Block upgrade Falcon 9.
Hey Chris, what exactly did you mean by this post?Quote from: ChrisGebhardt on 04/30/2017 10:10 amAlso, webcast would confirm if this is the first flight of the new Block upgrade Falcon 9.That the webcast telemetry would should a thrust increase? Or that the host(s) would tell us about an upgrade? Something else?
So much for the two launch a month cadence...
Quote from: Johnnyhinbos on 04/30/2017 11:34 amSo much for the two launch a month cadence... That's not really fair, NRO caused the majority of the slip. I think we have to let SpaceX slide on a one day. (if it grows... ok, phasers on whinge!!!! )... because if they go a nominal 12 or even 14 days between launches (planned) a one day slip still is 2 launches a month...
SpaceX never seems to launch and RTLS when the weather is this pretty.Sent from my LG-H850 using Tapatalk
Quote from: FutureSpaceTourist on 04/30/2017 10:33 amQuote from: ChrisGebhardt on 04/30/2017 10:09 amNRO PAO. NRO did not directly contract with SpaceX. They contracted with a private company who secured the contract to launch NROL-76 on a Falcon 9.QuoteThe SpaceX NROL-76 launch was not contracted to SpaceX directly by the NRO but through Ball Aerospace.https://twitter.com/nova_road/status/858629314341896192This really sounds like Ball is the spacecraft contractor - and given what they does, points at the payload more likely to be LEO optical reconnaissance, no?
Quote from: ChrisGebhardt on 04/30/2017 10:09 amNRO PAO. NRO did not directly contract with SpaceX. They contracted with a private company who secured the contract to launch NROL-76 on a Falcon 9.QuoteThe SpaceX NROL-76 launch was not contracted to SpaceX directly by the NRO but through Ball Aerospace.https://twitter.com/nova_road/status/858629314341896192
NRO PAO. NRO did not directly contract with SpaceX. They contracted with a private company who secured the contract to launch NROL-76 on a Falcon 9.
The SpaceX NROL-76 launch was not contracted to SpaceX directly by the NRO but through Ball Aerospace.
Quote from: Johnnyhinbos on 04/30/2017 11:34 amSo much for the two launch a month cadence...May could have 3.
Payload issues are part of the launch cadence.
Per L2 naughty "out of family" sensor that scrubbed the SpaceX Falcon 9 NROL-76 launch was a TOTO (Temperature Ox Tank Outlet) sensor. They had redundancy, but didn't want to risk losing another one, so the "abundance of caution" was as presented.
From the update thread:Quote from: Chris Bergin on 04/30/2017 12:35 pmPer L2 naughty "out of family" sensor that scrubbed the SpaceX Falcon 9 NROL-76 launch was a TOTO (Temperature Ox Tank Outlet) sensor. They had redundancy, but didn't want to risk losing another one, so the "abundance of caution" was as presented. It's not obvious to me why they are worried about losing another such TOTO sensor. If they have a redundant sensor, they know the temperature pre-launch. And once it's in flight, it should not matter if the sensor fails, since there is nothing they can do about it anyway.The only way I can see this being useful at all during flight is if they use it to optimize fuel usage or mixture adjustment. But as far as I know, this is normally done by volume remaining in the tank. They would want both tanks to run out at the same time, independent of the exact temperature of the LOX.
Quote from: Galactic Penguin SST on 04/30/2017 10:37 amQuote from: FutureSpaceTourist on 04/30/2017 10:33 amQuote from: ChrisGebhardt on 04/30/2017 10:09 amNRO PAO. NRO did not directly contract with SpaceX. They contracted with a private company who secured the contract to launch NROL-76 on a Falcon 9.QuoteThe SpaceX NROL-76 launch was not contracted to SpaceX directly by the NRO but through Ball Aerospace.https://twitter.com/nova_road/status/858629314341896192This really sounds like Ball is the spacecraft contractor - and given what they does, points at the payload more likely to be LEO optical reconnaissance, no?Given the ~51° orbit, which is not so well suited for optical payloads, perhaps it is a SAR satellite, perhaps something along the lines of the Ball built Radarsat-1 (http://space.skyrocket.de/doc_sdat/radarsat-1.htm)
Quote from: LouScheffer on 04/30/2017 02:12 pmQuote from: Chris Bergin on 04/30/2017 12:35 pmPer L2 naughty "out of family" sensor that scrubbed the SpaceX Falcon 9 NROL-76 launch was a TOTO (Temperature Ox Tank Outlet) sensor. They had redundancy, but didn't want to risk losing another one, so the "abundance of caution" was as presented. It's not obvious to me why they are worried about losing another such TOTO sensor. If they have a redundant sensor, they know the temperature pre-launch. And once it's in flight, it should not matter if the sensor fails, since there is nothing they can do about it anyway.The only way I can see this being useful at all during flight is if they use it to optimize fuel usage or mixture adjustment. But as far as I know, this is normally done by volume remaining in the tank. They would want both tanks to run out at the same time, independent of the exact temperature of the LOX.Proper characterization of the failure will impact future launches' reliability.
Quote from: Chris Bergin on 04/30/2017 12:35 pmPer L2 naughty "out of family" sensor that scrubbed the SpaceX Falcon 9 NROL-76 launch was a TOTO (Temperature Ox Tank Outlet) sensor. They had redundancy, but didn't want to risk losing another one, so the "abundance of caution" was as presented. It's not obvious to me why they are worried about losing another such TOTO sensor. If they have a redundant sensor, they know the temperature pre-launch. And once it's in flight, it should not matter if the sensor fails, since there is nothing they can do about it anyway.The only way I can see this being useful at all during flight is if they use it to optimize fuel usage or mixture adjustment. But as far as I know, this is normally done by volume remaining in the tank. They would want both tanks to run out at the same time, independent of the exact temperature of the LOX.
Traditionally, this would have made sense. But now it's old, expendable rocket thinking. They can characterize the failure after the booster returns.
Ball makes small sats. Its only moderately heavy payloads have been Worldview 2 and 3, with a mass of 2600 kg.They've never made a 5000 kg sat, for example, unlike the major sat builders.So I am speculating NROL-76 is quite small, under 3000 kg.