Ariane question

[pmn1]

When the Ariane 5 design was being looked at, was a CCB design such as we see with Delta IV or Atlas V a possibility - it seems to me that gave a good way of getting both a launcher for satellites plus one with the capability every now and again for a mini-shuttle without making the launcher too big for satellite launches. <div class="Discussion_UserSignature"> </div>

 

[keermalec]

What is a CCB?<br /><br />The Ariane V was specifically designed to launch both the European Hermes shuttle and satellites. The Hermes Shuttle was abandonned after its cost estimate shot up. <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[gunsandrockets]

<What is a CCB?><br /><br />I believe the reference is to a Common Core Booster, as in the triple booster configuration of a Delta IV heavy, or the Falcon 9 heavy. <br />

 

[erikm]

I don't think Ariane 5 was designed with CCBs in mind. I seem to remember reading that a prime reason for developing Ariane 5 was the Hermes minishuttle, but that that would be light enough to launch on a fairly stock booster.<br /><br />The Jules Verne ATV apparently weighs 20 tons or so. Hermes would have to have been in the same weight range, which doesn't seem impossible. Maybe a CRV-oid lifeboat?<br /><br />Current Ariane-launched loads are lighter but they're destined for GEO.<br /><br />EM

 

[qso1]

I cannot recall if Ariane V was designed with CCB in mind but as I recall, the term CCB itself did not come to my attention until the USAF started referring to plans for boosters with common cores. This probably in the early 1990s or maybe late 80s when the NLS program was being proposed. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[keermalec]

<blockquote><font class="small">In reply to:</font><hr /><p><What is a CCB?> <br /><br />I believe the reference is to a Common Core Booster, as in the triple booster configuration of a Delta IV heavy, or the Falcon 9 heavy. <br /><p><hr /></p></p></blockquote><br />Many thanks! ;-)<br /><br />I don't think the CCB concept was ever considered for Ariane V as the vulcain engine is not powerful enough for lift-off without the help of solid boosters.<br /><br />Dividing vulcain engine thrust by the mass of the Ariane V core gives only 6 N/kg, or 0.6 Gs, which is insufficient for lift-off. RS-68 engine thrust divided by mass of the Delta-IV core however, gives 14.6 N/kg, or 1.5 Gs, which is sufficient for lift-off. <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[pmn1]

Would Europe have the ability to make an engine with the same power as that used on the Delta IV or Atlas V cores? <div class="Discussion_UserSignature"> </div>

 

[keermalec]

Probably, but there must be an economic incentive imho. The Ariane V is currently quite cost effective. If one compares the launch cost of an Ariane V (180 million USD for 16 tons to the ISS) and a Delta IV Heavy (254 million USD for 21.9 tons to the ISS) the costs per ton of payload are roughly the same.<br /><br />This would not be the case if the CCB concept was the best cost solution. It may be that the CCB idea gives greater payload flexibility but is not necessarilly cheaper than the cryogenic core + solid booster concept.<br /><br />I suppose if the ESA were to go the CCB way, they could bring together several Vulcain engines on the same booster and develope a Common Core rocket, like the Falcon 9 (which uses 9 Merlin engnes per booster). Developing a powerful engine is not necessarily the only way of obtaining a CCB rocket.<br /> <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[pmn1]

Some replies on the NASA Spaceflight site<br /><br />http://forum.nasaspaceflight.com/forums/thread-view.asp?tid=7979&posts=7&start=1 <div class="Discussion_UserSignature"> </div>

 

[vulture2]

I believe the logic behind the Ariane 5 (or is it V) was very much the same as that of the Shuttle. Flexibility in payload mass was not a requirement, the LH2 engine didn't have the thrust for launch and the solid fuel boosters saved development cost compared to liquid fuel strap-ons. However it would be quite interesting to know how the operating cost of the solid boosters compares with a liquid fuel booster of similar performance. The boosters are much smaller than those on the Shuttle but still must be assembled from segments.<br /><br />The Delta IV Heavy could have used large solid boosters or even LOX/kerosine boosters like the Energia, but the remarkably high thrust of the RS-68 (for a LH2 engine) made the CCB approach possible and the reduction in the number of different components reduced the cost somewhat, probably making it the best choice at the time. <br />

 

[gunsandrockets]

<The boosters are much smaller than those on the Shuttle but still must be assembled from segments.><br /><br />What a pain it must be to ship those segments all the way to South America and then assemble them into a booster!