Atlas-V with RL10C powered Centaur

• Atlas-V with RL10C powered Centaur by Skyrocket on 05 Jun, 2014 11:03
• Some questions, as the NROL-35 mission in December 2014 will be the first Atlas-V mission featuring a Centaur upper stage with a RL10C-1 engine (http://www.spaceflightnow.com/news/n1406/04rl10c/): 
  
  Has anyone found the performance specifications of the RL10C versions of the Atlas-V rocket?
  
  Will these versions get a new designator to destinguish between RL10A and RL10C versions?
• #1 by MP99 on 05 Jun, 2014 11:20
• This was new to me.
  
  

  Quote

  Sowers said the RL10C will become the standard upper stage engine for all of the company's Atlas 5 and Delta 4 launches. An exception will be for the two-engine version of the Atlas 5's Centaur upper stage, which will continue flying with the RL10A-4-2 version of the engine.
  
  The shape of the RL10C's bell-shaped nozzle prevents two of the engines from being placed side-by-side in a dual-engine configuration, Sowers said.
  
  ...
  
  "The original plan was to go to all RL10Cs, but when the commercial crew program came along, it had some unique requirements that drove the need to retain the RL10A capability," Sowers said.

  
  cheers, Martin
• #2 by kevin-rf on 05 Jun, 2014 12:01
• The trade is shorter burn time (short higher thrust needed for LEO insertion) for longer burn times with better ISP (larger payloads to HEO/GTO orbits).
  
  Not surprising... more interesting is they will need to put ACES on hold due to the RS-180 issue...
• #3 by muomega0 on 05 Jun, 2014 12:37
• Quote from: Skyrocket on 05 Jun, 2014 11:03

  Some questions, as the NROL-35 mission in December 2014 will be the first Atlas-V mission featuring a Centaur upper stage with a RL10C-1 engine (http://www.spaceflightnow.com/news/n1406/04rl10c/): 
  
  Has anyone found the performance specifications of the RL10C versions of the Atlas-V rocket?
  
  Will these versions get a new designator to destinguish between RL10A and RL10C versions?
  

  
  

  Quote from: ULA

  But further upgrades to ULA's rocket upper stages, including concepts to build long-duration deep space tugs and propellant depots, may take a back seat as focus grows on developing a powerful U.S.-built booster engine to end reliance on Russian propulsion.

  
  

  Quote from: kevin-rf on 05 Jun, 2014 12:01

  The trade is shorter burn time (short higher thrust needed for LEO insertion) for longer burn times with better ISP (larger payloads to HEO/GTO orbits).
  
  Not surprising... more interesting is they will need to put ACES on hold due to the RS-180 issue...

  
  taking a back seat....because developing depots and long-duration deep space tugs eliminates the need for an HLV.  This is why you cannot outsource the integrated architecture.
  
  
  
• #4 by Star One on 05 Jun, 2014 15:27
• 
  

  Quote from: kevin-rf on 05 Jun, 2014 12:01

  The trade is shorter burn time (short higher thrust needed for LEO insertion) for longer burn times with better ISP (larger payloads to HEO/GTO orbits).
  
  Not surprising... more interesting is they will need to put ACES on hold due to the RS-180 issue...
  

  
  Unfortunately it seems a case of for every step forward they have to take one back as well.
• #5 by fregate on 06 Jun, 2014 13:47
• Quote from: Skyrocket on 05 Jun, 2014 11:03

  Some questions, as the NROL-35 mission in December 2014 will be the first Atlas-V mission featuring a Centaur upper stage with a RL10C-1 engine (http://www.spaceflightnow.com/news/n1406/04rl10c/): 
  
  Has anyone found the performance specifications of the RL10C versions of the Atlas-V rocket?
  
  Will these versions get a new designator to destinguish between RL10A and RL10C versions?
  

  Gunter, AFAIK RL10C-2 Engine (Boeing evaluated SLS Large Upper Stage with 4xRL10C-2 engine configuration as one of the options in 2013 LUS study The Space Launch System Capabilities with a New Large Upper Stage) should have the following:
  - thrust 24,750 lbf
  - specific impulse Isp vac = 462.5 s
  
  Aerojet Rocketdyne also is planning to manufacture RL10C-1 engines for
  

  Quote

  "a contract from Stratolaunch Systems Corporation (SSC) to provide six RL10C-1 production engines, with an option to provide an additional six RL10C-1 production engines at a later date, for the third stage of a revolutionary commercial air-launch system. The inaugural launch of Thunderbolt, the air-launch vehicle designed and developed for SSC, is scheduled for 2018."

  From spaceflight article it is still unclear which particular version of engine would be used for a common upper stage - S.Clarke mentioned engine family (RL10C).   
   
  
• #6 by edkyle99 on 06 Jun, 2014 16:11
• Quote from: Skyrocket on 05 Jun, 2014 11:03

  Some questions, as the NROL-35 mission in December 2014 will be the first Atlas-V mission featuring a Centaur upper stage with a RL10C-1 engine (http://www.spaceflightnow.com/news/n1406/04rl10c/): 
  
  Has anyone found the performance specifications of the RL10C versions of the Atlas-V rocket?
  
  Will these versions get a new designator to destinguish between RL10A and RL10C versions?
  

  Quote from: Skyrocket on 05 Jun, 2014 11:03

  Some questions, as the NROL-35 mission in December 2014 will be the first Atlas-V mission featuring a Centaur upper stage with a RL10C-1 engine (http://www.spaceflightnow.com/news/n1406/04rl10c/): 
  
  Has anyone found the performance specifications of the RL10C versions of the Atlas-V rocket?
  
  Will these versions get a new designator to destinguish between RL10A and RL10C versions?
  

  My understanding was that the 2013 Product Card provided performance for the RL10C versions and for the Common CBC version of Delta 4. Here's why I think that is true.
  http://forum.nasaspaceflight.com/index.php?topic=32176.0
  
   - Ed Kyle
• #7 by fregate on 09 Jun, 2014 06:18
• PowerPoint presentation Cryogenic Propulsion Stage by David Jones from Marshall Space Flight Center, HAT CPS Element Lead (Sep 2011) on page 10 lists RL10C-1 specifications as following:
  
  Cycle type - expander
  Vacuum thrust 23,900 lbf (10,841 kgf)
  Vacuum Isp, 448.5 sec
  Engine dry mass 419 lbm (191 kg)
  Engine Diameter, 56.8 in (1.443 m)
  Engine Length, 87.2 in (2.215 m)
  Mixture Ratio 5.88
  Chamber pressure 633 psia (4.364 mPa)
  Expansion ratio 130
  Nozzle 1 Fixed
  Throttle Fixed Throttle
  Restartable Yes
  Life expectancy 2,000 sec