Did we have this study yet?Evaluation of Future Ariane Reusable VTOL Booster stages
“Main goal is to compare costs but is tricky due to lack of knowledge of the operational costs”
Favorite line:Quote from: “Main goal is to compare costs but is tricky due to lack of knowledge of the operational costs”Understated.They don't think they can do return to launch site, but can handle down range landing. Like BO.Which suggests that they don't believe in "gas n go" turnaround. Lower cadence than rival.The heating issues suggest they've studied those landed boosters carefully.
Therefore, different mission trajectories were calculated with the DLR in-house tool toscaand were compared to telemetry data provided by the SpaceX launch webcasts.
All of this makes sense. The goal for them is to close the gap by enough of a demonstrator that handles a recoverable booster, where the down range recovery of a full scale booster with its lower cadence and higher number of high quality reuse allows enough advantage.Two ways of factoring this in to Ariane.Simplest would be to replace the solids (ESR P120's) with a barge landed methalox boosters (2-4), possibly also on Vega. You'd recover and reprocess. Disadvantage would be in the continued cost of the LLPM. But you'd have the most compact, cost effective program that could allow Ariane 6 to proceed with a phase over to partial reuse with little interruption in plan. And if the demonstrator was scaled to an appropriate size ... one could combine demonstrator program to a follow-on flight demonstration, easing into use.Most economic for the long run would be to replace the launcher architecture to take most advantage of a single recoverable booster of the scale to loft ULPM and payload. But that would not be compatible with existing facilities/operations. (However it would have the unique advantage of possibly handling RTLS, gas-n-go, and competing with BFR's CONOPs, should those like DLR suddenly get the inspiration to find it "economic" )None of this would be Ariane 6 as described.
Quote from: Space Ghost 1962 on 10/27/2017 11:37 pmFavorite line:Quote from: “Main goal is to compare costs but is tricky due to lack of knowledge of the operational costs”Understated.They don't think they can do return to launch site, but can handle down range landing. Like BO.Which suggests that they don't believe in "gas n go" turnaround. Lower cadence than rival.The heating issues suggest they've studied those landed boosters carefully.I don't think so. SpaceX has not given them access to the landed boosters. At best they could have studied the images of landed boosters. And those are "clouded" at best due to all the soot on the stages.
Other than that they studied the telemetry from the SpaceX webcasts (which is extremely limited in nature and subject to "filtering"):Quote from: DLRTherefore, different mission trajectories were calculated with the DLR in-house tool toscaand were compared to telemetry data provided by the SpaceX launch webcasts.
Quote from: Space Ghost 1962 on 10/27/2017 11:37 pmAll of this makes sense. The goal for them is to close the gap by enough of a demonstrator that handles a recoverable booster, where the down range recovery of a full scale booster with its lower cadence and higher number of high quality reuse allows enough advantage.Two ways of factoring this in to Ariane.Simplest would be to replace the solids (ESR P120's) with a barge landed methalox boosters (2-4), possibly also on Vega. You'd recover and reprocess. Disadvantage would be in the continued cost of the LLPM. But you'd have the most compact, cost effective program that could allow Ariane 6 to proceed with a phase over to partial reuse with little interruption in plan. And if the demonstrator was scaled to an appropriate size ... one could combine demonstrator program to a follow-on flight demonstration, easing into use.Most economic for the long run would be to replace the launcher architecture to take most advantage of a single recoverable booster of the scale to loft ULPM and payload. But that would not be compatible with existing facilities/operations. (However it would have the unique advantage of possibly handling RTLS, gas-n-go, and competing with BFR's CONOPs, should those like DLR suddenly get the inspiration to find it "economic" )None of this would be Ariane 6 as described.Naturally. But this is not for Ariane 6. It is for AriaNEXT. If there ever will be such beyond Ariane 6...
The x5 picture with SRB replacement by 2 flyback engines pods is probably lowest risk. This has advantage of one expendable fuel tank in centre stage along with x1 sustainer engine. The pair of engines pods flyback using Adeline concept. No need for downrange recovery, reuse is simple bolt them on new LV, can use existing US.Payload penalty is lower than booster recovery. ULA also have picture of similar concept except they don't have sustainer engine just big disposable tank, with 2 flyback engine pods.For moderate flight rates this maybe better system.
Quote from: woods170 on 10/28/2017 03:58 pmNaturally. But this is not for Ariane 6. It is for AriaNEXT. If there ever will be such beyond Ariane 6...Beg to differ. Matter of perspective on global events (and seemingly unrelated idiocies).Economics are a powerful motivator. One may want N vehicles to accommodate the sequencing from "current" to "next".What I've noticed before is the interesting ways that being painted into an economic corner, people rationalize an escape. Please note that Ariane 6 was to be a "PPH", not a Ariane 5 redux that it is becoming.Smart people always surprise you. Sometimes even surprise themselves.(Translation: they'll need more than will be allowed, they'll be a crisis, they'll get half a loaf, they'll adapt to get more to do "good enough", and the situation will ultimately close. My hunch if you will.)
Naturally. But this is not for Ariane 6. It is for AriaNEXT. If there ever will be such beyond Ariane 6...
Did we have this study yet?
Quote from: calapine on 10/27/2017 02:38 pmDid we have this study yet?Rather curious that they optimize for GTO while the most likely market for a reusable launcher will be LEO.
IMO Ariane 6 will have a short life once the absolute necessity of having a reusable booster stage sinks in hard. That, however, is still some time away. Once it does sink in however the Ariane 6 basic design will serve, IMO, as the starting point for an AriaNEXT. The result, with reusability capabilities will not be an Ariane 6 re-hash but basically an almost all-new rocket: Ariane 7. The only re-use capabilities we will ever see on Ariane 6, IMO, concern re-usable fairings.
Reusability is killing all the jobs in the solid rocket motor industry. This is not going to happen anytime soon. We are going to fly expendable rockets for a long time. Europe made a huge strategic mistake introducing solid rocket boosters with Ariane 3.What can Italy contribute to a reusable rocket? Almost nothing.
Some people don’t realize how strong is the Italian influence in the European launcher sector in particular within ESA, despite being only the 3rd contributor after France and Germany.
Quote from: Mike Jones on 10/29/2017 07:38 pmSome people don’t realize how strong is the Italian influence in the European launcher sector in particular within ESA, despite being only the 3rd contributor after France and Germany."Some people" = me? But seriously, I reject that as too pessimistic. If there is enough pressure from the outside than suddenly "there is a solution". That's the typically European way of doing things. It's the same with the European Union: Without a crisis no meaningful change happens.