Quote from: niwax on 11/17/2018 08:20 pmQuote from: woods170 on 11/17/2018 08:12 pmQuote from: TrevorMonty on 11/17/2018 08:09 pmWell that was 933 posts for nothing.What did you expect? This is Elon Musk we are talking about.It's also NSF. This forum could spend 933 posts discussing if the next BFR will be chicken-powered.Chicken power confirmed!
Quote from: woods170 on 11/17/2018 08:12 pmQuote from: TrevorMonty on 11/17/2018 08:09 pmWell that was 933 posts for nothing.What did you expect? This is Elon Musk we are talking about.It's also NSF. This forum could spend 933 posts discussing if the next BFR will be chicken-powered.
Quote from: TrevorMonty on 11/17/2018 08:09 pmWell that was 933 posts for nothing.What did you expect? This is Elon Musk we are talking about.
Well that was 933 posts for nothing.
Quote from: Lars-J on 11/17/2018 08:27 pmQuote from: niwax on 11/17/2018 08:20 pmQuote from: woods170 on 11/17/2018 08:12 pmQuote from: TrevorMonty on 11/17/2018 08:09 pmWell that was 933 posts for nothing.What did you expect? This is Elon Musk we are talking about.It's also NSF. This forum could spend 933 posts discussing if the next BFR will be chicken-powered.Chicken power confirmed! How manys chickens per booster and what breed. These questions should keep us going till Elon's next tweet.
https://twitter.com/elonmusk/status/1063865779156729857
Quote from: FutureSpaceTourist on 11/17/2018 06:58 pmhttps://twitter.com/elonmusk/status/1063865779156729857Funny, I thought this had been dead since 2014. When you factored in the massive increase in KE and PE for orbital velocity, multiplied by the fact you trade 1 for 1 on a US rather than the 6 to 1 to 13 to 1 for the booster stage Although I respect that the SX design team must have moved heaven and Earth to make it work without losing an unfeasible amount of payload.
Quote from: john smith 19 on 11/18/2018 07:35 pmQuote from: FutureSpaceTourist on 11/17/2018 06:58 pmhttps://twitter.com/elonmusk/status/1063865779156729857Funny, I thought this had been dead since 2014. When you factored in the massive increase in KE and PE for orbital velocity, multiplied by the fact you trade 1 for 1 on a US rather than the 6 to 1 to 13 to 1 for the booster stage Although I respect that the SX design team must have moved heaven and Earth to make it work without losing an unfeasible amount of payload.Trailing ballute seems like one plausible solution that makes it seemingly work to greatly reduce heat flux.It could also be applicable to S1 - and reduce or eliminate the need for an entry burn.This may buy back some of the penalty, especially for FH high energy launches.It could also be applicable to aerocapture for Mars for non-BFS.They backed off on public statements about how much they were going to reuse shortly after first launch - since then there have been various statements going from 'testing' to learning to 'complete reuse in 2-3 years for $6M'.It's been very far from clear it was dead, though it seems so now, who knows what the next tweet will say?
If there is no intention to make the second stage reusable, how much benefit would there be to recovering it? What information could be gleaned to make it perform more effectively? The stage is already functioning fine, isn't it?
Quote from: TrevorMonty on 11/18/2018 09:16 amQuote from: Lars-J on 11/17/2018 08:27 pmQuote from: niwax on 11/17/2018 08:20 pmQuote from: woods170 on 11/17/2018 08:12 pmQuote from: TrevorMonty on 11/17/2018 08:09 pmWell that was 933 posts for nothing.What did you expect? This is Elon Musk we are talking about.It's also NSF. This forum could spend 933 posts discussing if the next BFR will be chicken-powered.Chicken power confirmed! How manys chickens per booster and what breed. These questions should keep us going till Elon's next tweet.Not actually chickens, they are falcons. Don't know what breed.
Trailing ballute seems like one plausible solution that makes it seemingly work to greatly reduce heat flux.It could also be applicable to S1 - and reduce or eliminate the need for an entry burn.This may buy back some of the penalty, especially for FH high energy launches.It could also be applicable to aerocapture for Mars for non-BFS.
From my back of the envelope calculations, for a 150 x 35622 km GTO, I get an apogee speed of 1598 m/s. Lowering perigee to 75 km requires an apogee speed of 1590 m/s, a deltaV of only 8 m/s. That of course is a Hohmann transfer and current S2 design may make surviving that long difficult. Did you assume your delta V happens soon after satellite deploy when both it and S2 are going fast ? That will definitely cost much more fuel there.