Talk:Mass ratio

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Omitting aircraft stuff from intro

I've never seen a mass ratio used to describe an aircraft, and the inclusion of aircraft in the intro paragraph makes it unnecessarily vague and confusing. If you can cite a use of a mass ratio in the context of an aircraft that's not a rocket, please feel free to re-add the deleted material. --P3d0 03:22, 13 August 2007 (UTC)[reply]

Questions

I've got a couple of questions. They may just be silly questions but bear with me.

You mention that this is a "back-of-the-envelope" calculation: Does this mean it's an approximation (and if so, how good?) or just that it's easy?

It's not clear to me whether this equation takes into account the fact that as you're travelling and using fuel, the wet mass of the rocket will change. Is this under the approximation that the mass is constant, and it's kind of an average velocity? (This may not be relevant here but I thought I'd ask anyway)

Also from what I gather the Tsiolkovsky rocket equation is used in stages. Is the mass ratio also calculated in stages?

One suggestion I have is maybe defining $\Delta v$ early on for the less technically inclined reader (ie, ... the change in velocity, $\Delta v$ ...). Also you've left off a 'v' in math tag in the current last sentence.

This is a well written article btw. Kudos P3d0 --JT 02:35, 17 August 2007 (UTC)[reply]