SolarCellCoverage:

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   Evaluates the required solar cell coverage for a particular airship 
   hull geometry, as a function of the required power, the solar cell 
   efficiency, the global irradiance, and the daily fraction of
   sun-exposure
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   Form:
   R = SolarCellCoverage( h, u, S, Cd, P0, Emax, fSun, etaProp, etaCell );
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   ------
   Inputs
   ------
   h           (1)       Altitude                             [m]
   u           (1)       Velocity                             [m/s]
   S           (1)       Reference aera                       [m^2]
   Cd          (1)       Zero-incidence drag coefficient
   P0          (1)       Nominal power required for payload   [W]
   EMax        (1)       Maximum solar irradiance             [W/m^2]
   fSun        (1)       Daily fraction of sun exposure
   etaProp    (1,M)      Propeller/engine efficiency
   etaCell    (1,N)      Solar cell efficiency

   -------
   Outputs
   -------
   R          (M,N)      Required solar cell coverage ratio:
                           solar cell area / hull surface area

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Children:

Common: Atmosphere/StdAtm
Common: Graphics/NewFig