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The [possible] solution for Ares-1 "vibrations"
January 28, 2008

I've found very strange the fact that NASA released a news about a possible Ares-1 vibration issue since it's (simply) one of hundreds problems every new design faces (until all them are solved and the rocket flies) problems, usually NEVER revealed to the public not even when they are fixed... that's why it sounds me like a (possible) "excuse" to scrap the bad designed Ares-1, now or when they will realize that it can't fly (as explained in the Ares-1 can't fly and Ares-1 second stage MYSTERY articles) and is (also) too expensive.

The best solution to solve the "vibrations" and all other Ares-1 problems, is to scrap this rocket from the ESAS plan and restart with "something better" or (at least) adopt a different design like MY new Ares-1 or MY Ares-F.

However, if they (absolutely) want to build THIS Ares-1 with its 5-segments SRB a possible solution for the Ares-1 vibrations is to add four small fins in the middle of the rocket, joined to the 1st/2nd stages' interstage.

Since the "thrust oscillation issue" should affect only the 1st stage of the Ares-1 the fins will work like an aerodynamic "rail" that, at supersonic speed, will force the rocket into a correct traiectory replacing the stabilizing effect of the Shuttle+ET stack, to reduce/eliminate the SRB's "vibrations".

The fins may work very well since, the 1st stage, is jettisoned at 56 km. of altitude, then, it always fly in the dense (or enough) atmosphere, also, this solution may solve another possible (and largely unknown) problem revealed in this August 3, 2006 press release, where NASA admits that "The "biggest unknown" for engineers, remains how to control the Ares 1 steering and roll during flight. Engineers are using computer models and other analyses to solve the problem.".

The fins should be not joined to the 1st stage SRB (to avoid the redesign of the booster and a further increase of the R&D time and cost) nor to the 2nd stage (to avoid to add more dry mass) but could be joined to the rocket's interstage so, that fins, will be jettisoned with the 1st stage.

To keep to the minimum the influence of these fins to the rocket's specs, performances and payload they could be made with light alloys, carbon fibers and composite materials to have very strong fins with a modest increase of weight (that could be in the range of half mT).

[update] Talking about this idea on Space forums and blogs, I've realized that there is a basic misunderstanding since many forums' users say that: "aerodynamics has nothing to do with vibrations". That's true since, the purpose of the fins, is NOT to produce any "negative vibrations" (to match the positive vibrations of the 1st stage SRB) but, simply, to create an "aerodynamic counterforce" that DOESN'T ELIMINATE these "vibrations" but only its EFFECT, stabilizing the rocket, since, at multi-sonic speed the fins work like "blades" in the air (or like a train on its rail).

As already explained before, the fins can double their effect (also) as rocket's steering and roll control that doesn't need any actuators, electronics and energy source, since the fins add a strong "stabilizing force" to be "refined" using the attitude control jets.

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