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Varible clarification please - Printable Version

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Varible clarification please - Matt Agajanian - 09-04-2017 06:35 AM

Hi all.

I found this variation of our famous Mach Formula in the . From what I gather, Vc is aircraft speed (350 from the HP manuals formula). But what is the name of the variable is the Delta variable in the 1/Delta portion of this picture?

Thanks

Mach formula


RE: Varible clarification please - Maximilian Hohmann - 09-04-2017 09:42 AM

Hello,

Rho is the density of the gas. All the fancy factors in this equation are valid for specific units of speed and density only. Without supplying these, the equation is not really useful I'm afraid.

Regards
Max


RE: Varible clarification please - SlideRule - 09-04-2017 10:23 AM

(09-04-2017 06:35 AM)Matt Agajanian Wrote:  ... what is the name of the variable is the Delta variable in the 1/Delta portion of this picture?

Matt

A partial explanation is available at Flight Instruments under the heading The Math (about ¹⁄₄ page scroll down). This doesn't exactly answer your question but it's a start. Hope it helps.

BEST!
SlideRule


ps: keep scrolling, there is additional math(clarification/explanation) further down.


RE: Varible clarification please - Matt Agajanian - 09-04-2017 06:59 PM

That seems to help. See, the way I figure it, after spending so much time with the formula we know & love, although that formula is based on speed & altitude, this one is for a specific purpose as the one I found has a different purpose/application and bases its formula on different variables (even though most of that looks identical to the one in HP manuals). Right?