What I find disturbing is that the fifth set of engines are only required in 2027, so there will only be four SLS flying in the next 11 years? I was under the impression that they'd be aiming at a somewhat higher launch cadence.
Will the new production line be able to produce 8 engines per year instead of 0.75 per year?Is that another billion dollar effort?Did anyone ever produce 8 RS-25s in a year?
Engine production rate shown is set at two engines per year, which is the SLS Program baseline steady state need and therefore establishes the manufacturing infrastructure and labor force size.
On the positive side, once the US Government pays to restart production of the RS25 as well as updating the design for modern fabrication methods and a fewer part count, it will be another option on the shelf for future launch vehicle designs. A lot of people have said the RS25 is an amazing engine, it is just expensive. Well, these investments will eventually make RS25 a lot cheaper to some future user if they step forward.
Quote from: Todd Martin on 01/06/2016 02:44 amOn the positive side, once the US Government pays to restart production of the RS25 as well as updating the design for modern fabrication methods and a fewer part count, it will be another option on the shelf for future launch vehicle designs. A lot of people have said the RS25 is an amazing engine, it is just expensive. Well, these investments will eventually make RS25 a lot cheaper to some future user if they step forward.This "it will be cheaper" thing tends to, you know, fail to happen.A semi-random example: ULA was supposedly created to make launches cheaper. After which they become more expensive.
To be more precise. One engine takes about 5 years to make. The factory has the capacity to start working on two new engines per year. This means that after 5 years (and assuming that each year you add two new engines to production), 2 engines are delivered for integration. And two for every year after that. So, the factory can hold 10/12 engines inside, in various stages of production/delivery. I might have this wrong.
Quote from: Dante80 on 01/06/2016 12:43 pmTo be more precise. One engine takes about 5 years to make. The factory has the capacity to start working on two new engines per year. This means that after 5 years (and assuming that each year you add two new engines to production), 2 engines are delivered for integration. And two for every year after that. So, the factory can hold 10/12 engines inside, in various stages of production/delivery. I might have this wrong.A rate of 2 a year is a head scratcher. It literally doesn't add up. One SLS needs 4 engines, they want to get into a launch cadence of at least once a year. A rate of two engines a year means a launch every two years. If the contract really does call for two engines a year then eventually they will have to ramp up capability or reduce the flight rate.
To be more precise. One engine takes about 5 years to make. The factory has the capacity to start working on two new engines per year. This means that after 5 years (and assuming that each year you add two new engines to production), 2 engines are delivered for integration. And two for every year after that.
Quote from: Dante80 on 01/06/2016 12:43 pmTo be more precise. One engine takes about 5 years to make. The factory has the capacity to start working on two new engines per year. This means that after 5 years (and assuming that each year you add two new engines to production), 2 engines are delivered for integration. And two for every year after that. 5 years to build an engine!?!?!
Quote from: Lars-J on 01/06/2016 04:15 pmQuote from: Dante80 on 01/06/2016 12:43 pmTo be more precise. One engine takes about 5 years to make. The factory has the capacity to start working on two new engines per year. This means that after 5 years (and assuming that each year you add two new engines to production), 2 engines are delivered for integration. And two for every year after that. 5 years to build an engine!?!?!From the JOFOC.ARJ hand builds their engines (at least, that's what I knew they did in the past).
Quote from: Dante80 on 01/06/2016 04:20 pmQuote from: Lars-J on 01/06/2016 04:15 pmQuote from: Dante80 on 01/06/2016 12:43 pmTo be more precise. One engine takes about 5 years to make. The factory has the capacity to start working on two new engines per year. This means that after 5 years (and assuming that each year you add two new engines to production), 2 engines are delivered for integration. And two for every year after that. 5 years to build an engine!?!?!From the JOFOC.ARJ hand builds their engines (at least, that's what I knew they did in the past). This is the production process I imagine for a 5 year build process: (see image) It's no wonder the surviving RS-25's are treated like precious commodities.(Meanwhile, another domestic liquid engine produces over 100 engines per year)
This is the production process I imagine for a 5 year build: (see image) It's no wonder the surviving RS-25's are treated like precious commodities.
It will be some time before launches catch up though. The contract seems to be for 6 engines, the first two of which will be delivered for integration in 2022. By the time they are used all (2027), a new contract placed before 2022 would have another 10 engines ready by then (I don't count 2 engines that will remain for spares).If we assume 1 SLS launch per year (from 2028 onwards), then launches will catch up with production in..2032 (EM-10 or EM-11).