3) The Falcon 9 is not well-suited to LEO constellations because it is structurally limited to half its performance as well as fairing volume-limited.
Quote from: dante2308 on 07/27/2018 12:43 pm3) The Falcon 9 is not well-suited to LEO constellations because it is structurally limited to half its performance as well as fairing volume-limited.If even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).
Quote from: Oli on 07/27/2018 01:12 pmQuote from: dante2308 on 07/27/2018 12:43 pm3) The Falcon 9 is not well-suited to LEO constellations because it is structurally limited to half its performance as well as fairing volume-limited.If even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).Ariane 64 doesn't actually have much better performance than F9R to the 600-1200 km circular orbits where constellations are actually inserted, despite costing considerably more.In order to match the cost per kg that Iridium is paying, OneWeb would need to be getting ready Soyuz for $42 million including the dispenser. I rather doubt that they are anywhere near that.So yes, F9 is just fine for LEO, even before any serious price reductions due to reuse.
Quote from: Oli on 07/27/2018 01:12 pmQuote from: dante2308 on 07/27/2018 12:43 pm3) The Falcon 9 is not well-suited to LEO constellations because it is structurally limited to half its performance as well as fairing volume-limited.If even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).I don't think structural limitations are insurmountable. However we're talking about a factor of two here so I don't think it's trivial or that it's a fait accompli. It'll take some work that hasn't happened. The last word on why the Falcon Heavy was delayed from an engineering perspective was to prepare it to handle a different regime of structural loads and the resulting delay was... significant.
Quote from: Oli on 07/27/2018 01:12 pmIf even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).Ariane 64 doesn't actually have much better performance than F9R to the 600-1200 km circular orbits where constellations are actually inserted, despite costing considerably more.
If even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).
Quote from: envy887 on 07/27/2018 01:36 pmQuote from: Oli on 07/27/2018 01:12 pmQuote from: dante2308 on 07/27/2018 12:43 pm3) The Falcon 9 is not well-suited to LEO constellations because it is structurally limited to half its performance as well as fairing volume-limited.If even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).Ariane 64 doesn't actually have much better performance than F9R to the 600-1200 km circular orbits where constellations are actually inserted, despite costing considerably more.In order to match the cost per kg that Iridium is paying, OneWeb would need to be getting ready Soyuz for $42 million including the dispenser. I rather doubt that they are anywhere near that.So yes, F9 is just fine for LEO, even before any serious price reductions due to reuse.It's a wash if you take the Falcon 9 Black 5 against the Ariane 64 in terms of price. If a Block 6 comes around all bets are off.
Quote from: envy887 on 07/27/2018 01:36 pmQuote from: Oli on 07/27/2018 01:12 pmIf even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).Ariane 64 doesn't actually have much better performance than F9R to the 600-1200 km circular orbits where constellations are actually inserted, despite costing considerably more.600-1200km is part of LEO, I am aware of that. I was talking about plane changes.
Yes, I was agreeing with you. Constellation satellites typically can do their own plane changes by changing altitude and thus precession rate relative to the rest of the constellation, so that's not a deal breaker.
Quote from: dante2308 on 07/27/2018 01:40 pmQuote from: envy887 on 07/27/2018 01:36 pmQuote from: Oli on 07/27/2018 01:12 pmQuote from: dante2308 on 07/27/2018 12:43 pm3) The Falcon 9 is not well-suited to LEO constellations because it is structurally limited to half its performance as well as fairing volume-limited.If even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).Ariane 64 doesn't actually have much better performance than F9R to the 600-1200 km circular orbits where constellations are actually inserted, despite costing considerably more.In order to match the cost per kg that Iridium is paying, OneWeb would need to be getting ready Soyuz for $42 million including the dispenser. I rather doubt that they are anywhere near that.So yes, F9 is just fine for LEO, even before any serious price reductions due to reuse.It's a wash if you take the Falcon 9 Black 5 against the Ariane 64 in terms of price. If a Block 6 comes around all bets are off.Only at the actual price for Iridium ($70M per 10) and the best possible price for A64 (€90M per 15). If A64 is going to cost more like €105M list price unless they get more EU institutional launches, and you take the $62.2M list F9R price that's a considerable difference. Iridium would have needed $611 million (plus dispenser costs) for 5 A64 launches compared to $492 for 7 F9 launches to get their 70 sat base constellation up.That's about a 20% difference which is quite significant, and it doesn't even account for SpaceX reportedly selling F9R for well below list price recently, at closer to $50M.Quote from: Oli on 07/27/2018 01:51 pmQuote from: envy887 on 07/27/2018 01:36 pmQuote from: Oli on 07/27/2018 01:12 pmIf even true those limitations can arguably be overcome relatively easily. F9 looks like a cheaper LEO rocket to me unless maybe plane changes are involved. That would imply a low number of sats per plane though, potentially as part of a replenishment strategy (just speculating).Ariane 64 doesn't actually have much better performance than F9R to the 600-1200 km circular orbits where constellations are actually inserted, despite costing considerably more.600-1200km is part of LEO, I am aware of that. I was talking about plane changes.Yes, I was agreeing with you. Constellation satellites typically can do their own plane changes by changing altitude and thus precession rate relative to the rest of the constellation, so that's not a deal breaker.
Quote from: envy887 on 07/27/2018 02:00 pmYes, I was agreeing with you. Constellation satellites typically can do their own plane changes by changing altitude and thus precession rate relative to the rest of the constellation, so that's not a deal breaker.Look up what an orbital plane change is.
The Iridium NEXT launches are supposed to cost $61.5 million a pop. (The $492 million for 8 launches signed in 2010)So 6.56 million US$ per sat. (75, not 80 total. The May launch only had 5 sats.)Ariane 64 can launch 15 in one go with ~8% payload reserve for plane changes and stage disposal. 6 million € per sat, using the current exchange rate 6.99 million US$.So constellation deployment on Ariane would cost an additional ~$3.25 million. (Much closer than I thought!)Ordering a block of five Ariane 64 launches might drop the price just that a bit. [If the nominal price of 90M€ for A64 is real.]That said Iridium NEXT will be deployed before Ariane 6 launches for the first time.
Ariane 64 and Falcon 9 are competitive for LEO constellations is about the gist of it. No one is going to lose serious money using one over the other and depending on how you break it down and what assumptions you use, either might come ahead.
Sure. As long as those assumptions don't include any price reductions with reuse. SpaceX is currently launching at A64 prices or lower, and an obvious path to even lower future costs (and prices, if needed). Ariane 64 pricing is still speculative and based on significant operational cost reductions form Ariane 5, with no apparent mechanism to further reduce costs or prices.
It's a wash if you take the Falcon 9 Black 5 against the Ariane 64 in terms of price.
If a Block 6 comes around all bets are off.
Elon Musk has said Block 5 is the last major iteration of the Falcon 9. The next transportation system they are focused on now is the BFR/BFS, which will eventually replace the Falcon 9/H - and be priced even less on a $/kg basis.