home page

 

<< Back to Articles' Directory

   A new Ares-I design   

Reading the last year's news, we know the problems of the Ares-I design, like the $3 billion SRB upgrade to the new 5-segments version (with the total R&D costs that may exceed $7 billion) the estimated 7+ years to design the new J-2x 2nd-stage engine and the funds' cuts that forced NASA to shift the first manned Orion launch from the (planned) "end of 2014" to the mid 2015.

As explained in my articles here (and in my posts on space forums and blogs) my opinion is that, great part of the problems, come from some bad (and still unchanged) choices made in the ESAS plan, like the decision to develop and build two different rockets, the use of new and costly engines and motors, a too big Orion designed for six astronauts (despite 99% of the missions will need three or four astronauts) etc.

However, with some simple design changes, the Ares-I can be built in less than 4 years (to fly in 2012 when the Orion will be ready) and at less than HALF the R&D costs of the current 5-segments-SRB/J-2x design (SAVING up to $4 billion!) also, the price of the new Ares-I hardware may fall to less than $80M (or $200M including the shared R&D costs for 25 test+operational orbital/lunar launches in the next 20 years) and the new Ares-I will be about 15% smaller and lighter!

Of course, the new Ares-I can't lift the planned (too heavy) Orion+SM+LAS but a lighter Truncated Biconic Shape Orion that needs a smaller Service Module and less propellent (in the standard, TEI-only version) and also a new underside LAS to SAVE up to 8 mT from the current Orion design.

Thanks to this giant mass saving the TBS-Orion (and its newLAS) can be launched with the standard 5-seg.SRB/J-2x Ares-I without any "underpower problem" but the current Ares-I design still keep unsolved ALL its costs and development time problems, then I suggest to change its design to a "two and half stage" version using a big SM to build a (resized) SwissKnife Orion.

The big SM of the SwissKnife-Orion has enough propellents for (both) LOI and TEI to be used with the Ares-IV to perform Apollo-8-like missions (with a smaller EDS) while, in the "standard" moon missions (with the Ares-V and the LSAM used for LOI) that extra SM propellent (and the SM engine) can be used as "third stage" to reach the LEO (for Moon and ISS missions).

The lighter Orion and the bigger SM (used as "third stage") need a smaller and lighter Ares-I, designed and built with ready available and (relatively) low cost engines, motors and hardware.

The "new Ares-I" first stage use the ready available, cheap, very reliable and man-rated standard 4-segments SRB, exactly the SAME used for the Space Shuttle but "expendable" (that is just a standard SRB used once!) since it costs a mere +10% over the reusable version (about $44M instead of $40M) but allows to cut the very high annual SRB-retrieval fixed costs (as explained on ghostNASA).

Since the standard SRB is a "dumb" motor (that needs the Shuttle's Orbiter energy, attitude control jets and computers to work) the new Ares-I can use the ready available (modified and re-programmed) DeltaIV or AtlasV attitude control jets and flight computers, to save very much time and money!

Of course, a smaller and lighter Orion, and the SM used as third stage, need a smaller and lighter 2nd stage that can be built with smaller and lighter tanks and four/five DeltaIV 2nd stage RL-10B-2 engines that (also) add further reliability to the Ares-I 2nd stage, since, if one of the engines will fail (like happened in the ApolloXIII flight with the SaturnV 2nd stage central J-2 engine) the flight (and the ENTIRE Moon mission!) doesn't need to abort and the Orion will always reach the LEO!

The Ascent Flight Profile of the new Ares-I will be pretty close to the old Ares version with the first stage SRB Separation at 50-55 km. of altitude, the second stage Engines Start at 55-60 km. but with the 2nd stage Engines Cutoff at a lower altitude than planned with the old J-2x Ares, then the Orion's engine will burn its "LOI propellent" to reach the LEO while the SM tanks will still store enough propellent
for a TEI burn in the following Moon mission.

Delete the 5-segments SRBs from the ESAS plan needs a redesign of the Ares-IV and Ares-V rockets that can be built with THREE (ready available, cheap, reliable and man-rated) expendable (standard) 4-segments SRB and three/five RS-68 (as suggested ten months ago in my Super SLV article) with the further advantage of a giant saving of time and money!

Of course, the new Ares-I design is only a "concept" that needs years of research to become real, also, the version suggested here is only one of dozens possible models, built with different engines, mass, etc.

March 28 - 2007

>>>>>>  If you talk/discuss about this argument on space forums/blogs/websites/magazines/articles please refer to the source of the idea and/or put a link to this article. Thank You. <<<<<<<<<<

Copyright © 2007 Gaetano Marano - All rights reserved - base images used for the drawings are © NASA

Home Page

 

 

Site Meter