Weight equation is giving me hard time: Weight = (V / 1,278)2 x A x
Weight equation is giving me hard time: Weight = (V / 1,278)2 x A x
(OP)
Hi,
Trying to find a min flying weight from this Eq:
Weight = (V / 1,278)2 x A x Cl (where Cl=0.9 , V=6 m/s A=0.72 m^2)
This equation yelds no result in mathcad. What am I doing wrong?
Thanks Morten
Trying to find a min flying weight from this Eq:
Weight = (V / 1,278)2 x A x Cl (where Cl=0.9 , V=6 m/s A=0.72 m^2)
This equation yelds no result in mathcad. What am I doing wrong?
Thanks Morten





RE: Weight equation is giving me hard time: Weight = (V / 1,278)2 x A x
also that 1.278 has units, if you are using those in mathcad.
I imagine the original equation was
1/2*airdensity*v^2*CL*A
Cheers
Greg Locock
RE: Weight equation is giving me hard time: Weight = (V / 1,278)2 x A x
Thanks for your input. I have now removed all units in the sheet and still no answer. My definitions seems alright - but I get not result when doing the Wmin=
Very odd.
Another thing I need the area in dm^2 not in m^2 How would I go about that?
Any ideas?
morten
RE: Weight equation is giving me hard time: Weight = (V / 1,278)2 x A x
Weight:1/2*airdensity*v^2*CL*A
Weight=
When you hit return on the second equation, Mathcad should display Weight=90000 or whatever.
dm is a non-standard unit in Mathcad, so at the top of the sheet, define dm:0.1m
then you can use dm as any other regular unit. Be careful not to redefine built-in units, as that can have disastrous effects on other dependent units in your calculations.
TTFN