Why not atlas or delta
So the question stands. If an alternate launcher (ULA or F9) has launched an Orbital Satellite based on the STAR bus, then is the payload interface compatible with Cygnus? What new work would have to be done?
The big issue with both SpaceX and ULA is finding a spare LV these are built to order. I doubt either company has spares. The alternative is to grab the LV from another scheduled government flight.
Orb/Cygnus was not really expected to launch again until Q1 2015, and the next one after that was in the Summer of 2015. So it does not appear to me they will miss much with a 6-9 month delay in launches. SpaceX has about 5 Dragon's planned for 2015, so it is not likely they could squeeze in any more.A year long delay OTOH, would definitely be a problem. Might have to order another ATV or HTV. Dragon does not do garbage duty either.
Quote from: TrevorMonty on 10/29/2014 05:27 pmThe big issue with both SpaceX and ULA is finding a spare LV these are built to order. I doubt either company has spares. The alternative is to grab the LV from another scheduled government flight.Launch vehicles are built to order.
A totally off the wall multiple part question:For the purposes of full non-perishable supply to ISS with the planned Cygnus craft.1) How many Cygnus could be lofted at a time by a Falcon Heavy?2) If close to the number of mission Orbital has planned for ISS in it's downtime would Orbital or Nasa consider placing them in a parking orbit and then sending Cygnus as needed from that orbit to ISS?3) Could a Cygnus remain parked in an orbit for a long time before being used? (batteries etc.)4) What would it take to convince Elon or Orbital to risk this on the Falcon Heavy test flight?
^^^ The fairing for FH isn't any bigger than the fairing for F9. So the FH doesn't buy you anything, can only loft one Cygnus per launch. I think F9 could lift the enhanced Cygnus (assuming it fits) fully loaded. Dragon is always volume, not payload limited and Cygnus doesn't have a trunk.
They also have a CRS contract with NASA, which might give NASA some leverage to make them add a Cygnus launch?
I am hoping the Antares mishap will motivate Orbital to pursue integration of Cygnus on Delta IV, both as a backup strategy for CRS if Antares doesn't return to flight soon, and as a forward-looking strategy to expand the capabilities of Cygnus beyond LEO ISS resupply.
I'm not sure which Delta IV M+ variant would be appropriate for launching an Enhanced Cygnus to ISS.
Quote from: sdsds on 11/01/2014 06:57 pmI am hoping [Orbital will] pursue integration of Cygnus on Delta IVDelta IV is one of the most expensive rockets in the world. Orbital has a fixed price contract. That is not going to happen.
I am hoping [Orbital will] pursue integration of Cygnus on Delta IV
Quote from: Lars-J on 10/29/2014 07:04 pm They also have a CRS contract with NASA, which might give NASA some leverage to make them add a Cygnus launch? OSC has a CRS contract too, they could contract ULA for launch services and this would be transparent to NASA. NASA has no leverage on Spacex or OSC to tell them which launch vehicle to use.
In another thread Dan thought of using Arianne if ULA isn't able to free up a core or two. Sure, Arianne has issues of its own, and has a spare Soyuz-ST that could be used for Cygnus, http://forum.nasaspaceflight.com/index.php?topic=34129.msg1268946#msg1268946a Win Win for both firms.