Quote from: jongoff on 04/18/2014 08:37 pmQuote from: jongoff on 04/18/2014 08:35 pmFalcon 9 stage 2 will be deorbited SW of Australia shortly; first time the second stage has been deorbited on an F9 flightI wonder whether this is being driven more by orbital debris considerations, wanting to practice relights on the second stage (building up experience for GTO missions), or if they're trying to use it to start gathering data for F9R upper stage reuse, or something else entirely.If the burn is to depletion it gives a data point on what total vehicle performance really is.
Quote from: jongoff on 04/18/2014 08:35 pmFalcon 9 stage 2 will be deorbited SW of Australia shortly; first time the second stage has been deorbited on an F9 flightI wonder whether this is being driven more by orbital debris considerations, wanting to practice relights on the second stage (building up experience for GTO missions), or if they're trying to use it to start gathering data for F9R upper stage reuse, or something else entirely.
Falcon 9 stage 2 will be deorbited SW of Australia shortly; first time the second stage has been deorbited on an F9 flight
Quote from: Avron on 04/18/2014 08:50 pm@elonmusk 1mLast known state for rocket boost stage is 360 m/s, Mach 1.1, 8.5 km altitude and roll rate close to zero (v important!)Hard to imagine a soft touchdown, this time anyway, if the last known state had the F9 at 28,000' going straight down at over Mach 1. Still, the very low roll rate is encouraging, and one can't wait to see yesterday's "Grasshopper II" video recreated after a live F9 launch.
@elonmusk 1mLast known state for rocket boost stage is 360 m/s, Mach 1.1, 8.5 km altitude and roll rate close to zero (v important!)
Quote from: Danderman on 04/18/2014 08:59 pmQuote from: AJA on 04/18/2014 08:56 pm2. They can still burn to depletion, while putting it in the predefined zone in the Pacific.By definition, burning to depletion and putting the second stage into a predefined "landing zone" in the Pacific are mutually exclusive, due to uncertainty in propellant consumption.It's kind of like saying " drive your car until it runs out of gas" and also "park the car carefully in the garage".lol.. but the garage is a VAST swathe of the Pacific.
Quote from: AJA on 04/18/2014 08:56 pm2. They can still burn to depletion, while putting it in the predefined zone in the Pacific.By definition, burning to depletion and putting the second stage into a predefined "landing zone" in the Pacific are mutually exclusive, due to uncertainty in propellant consumption.It's kind of like saying " drive your car until it runs out of gas" and also "park the car carefully in the garage".
2. They can still burn to depletion, while putting it in the predefined zone in the Pacific.
Quote from: TRS717 on 04/18/2014 08:58 pmQuote from: Avron on 04/18/2014 08:50 pm@elonmusk 1mLast known state for rocket boost stage is 360 m/s, Mach 1.1, 8.5 km altitude and roll rate close to zero (v important!)Hard to imagine a soft touchdown, this time anyway, if the last known state had the F9 at 28,000' going straight down at over Mach 1. Still, the very low roll rate is encouraging, and one can't wait to see yesterday's "Grasshopper II" video recreated after a live F9 launch.Actually this looks encouraging to me. From that altitude and speed, the first stage would need to decelerate at less than 2 gees to reach simultaneous zero altitude and velocity.
