/************************************************/
/* ECE-1011 Spring 2003                         */
/* Section:......... 0                          */
/* Assignment:...... 2                          */
/* Programmer:...... BAHN, William L.           */
/* File Contents:... SOURCE CODE                */
/* Filename:........ s20_key                    */
/* Due Date:........ 10 Feb 03                  */
/* E-mail Address:.. wbahn@eas.uccs.edu         */
/************************************************/


/*============== STANDARD LIBRARY INCLUDE FILES =============================*/

#include <stdio.h>  /* printf(), scanf() */

/*============== PROGRAMMER DEFINED CONSTANTS ===============================*/

/*****************************************************************************/
/* Version and Author Control                                                */
/*****************************************************************************/

#define VERSION  (2)
#define REVISION (5)
#define PROGRAMMER "William L. Bahn"
#define LASTMODDATE "17 FEB 2003"

/*****************************************************************************/
/* Parameters for a particular type of aircraft                              */
/*****************************************************************************/
/* AIRCRAFT_TYPE "Text String Description"                                   */
/* MIN_GROSS    (Minimum Gross Weight in pounds)                             */
/* MAX_GROSS    (Maximum Gross Weight in pounds)                             */
/* FWD_CG_MINGW (Fwd CG Limit @ MIN_GROSS)                                   */
/* FWD_CG_MAXGW (Fwd CG Limit @ MAX_GROSS)                                   */
/* FWD_CG_BRKGW (Weight at which FWD CG begins changing)                     */
/* AFT_CG_MINGW (AFT CG Limit @ MIN_GROSS)                                   */
/* AFT_CG_MAXGW (AFT CG Limit @ MAX_GROSS)                                   */
/* AFT_CG_BRKGW (Weight at which AFT CG begins changing)                     */
/*****************************************************************************/

#define AIRCRAFT_TYPE "T41-B"
#define MIN_GROSS     (1500.0)
#define MAX_GROSS     (2500.0)

#define FWD_CG_MINGW    (35.0)
#define FWD_CG_MAXGW    (40.5)
#define FWD_CG_BRKGW  (1950.0)

#define AFT_CG_MINGW    (47.0)
#define AFT_CG_MAXGW    (47.0)
#define AFT_CG_BRKGW  (1500.0)

/*****************************************************************************/

#define BLANKLINE printf("\n")

/*===========================================================================*/
/*=========================== MAIN FUNCTION =================================*/
/*===========================================================================*/

int main(void)
{
	/* Variable Dictionary */
	double empty_wt, empty_cg;            /* Aircraft Empty Weight and CG     */
	double fuel_wt, fuel_cg;              /* Fuel Weight and CG               */
	double frontpax_wt, frontpax_cg;      /* Front Occupants Weight and CG    */
	double rearpax_wt, rearpax_cg;        /* Rear Occupants Weight and CG     */
	double baggage_wt, baggage_cg;        /* Baggage Area Weight and CG       */
	double misc_wt, misc_cg;              /* Misc. Items Weight and CG        */
	double gross_wt, gross_cg, gross_mom; /* Total A/C Weight, CG, and Moment */
	double dx, dy;                        /* Dummy variables for slope cals   */
	double fwd_cg, aft_cg;                /* Computed CG Limits               */

	/* Section 1 - Print out Aircraft Parameters -----------------------------*/

	printf("===============================================================\n");
	printf("Aircraft CG Calculator Version %i.%i\n", VERSION, REVISION);
	printf("Programmer: %s\n", PROGRAMMER);
	printf("Date of Last Mod: %s\n", LASTMODDATE);
	printf("===============================================================\n");
	printf("This program computes the weight and balance for an aircraft\n");
	printf("described by the following CG Envelope:\n");
	BLANKLINE;
	printf("Aircraft Type: %s\n", AIRCRAFT_TYPE);
	BLANKLINE;
	printf("Gross Weight Limitations:\n");
	printf("  The minimum aircraft gross weight is %7.1f pounds.\n", MIN_GROSS);
	printf("  The maximum aircraft gross weight is %7.1f pounds.\n", MAX_GROSS);
	BLANKLINE;
	printf("Forward CG Limitations:\n");
	printf("  For Aircraft Gross Weight below %7.1f lb:\n", FWD_CG_BRKGW);
	printf("    FWD CG Limit is %6.2f\" aft of the datum.\n", FWD_CG_MINGW);
	printf("  For Aircraft Gross Weight between %7.1f lb and %7.1f lb:\n",
			FWD_CG_BRKGW, MAX_GROSS);
	printf("    FWD CG Limit moves linearly from %6.2f\" to %6.2f\".\n",
			FWD_CG_MINGW, FWD_CG_MAXGW);
	BLANKLINE;
	printf("Aft CG Limitations:\n");
	printf("  For Aircraft Gross Weights below %7.1f lb:\n", AFT_CG_BRKGW);
	printf("    AFT CG Limit is %6.2f\" aft of the datum.\n", AFT_CG_MINGW);
	printf("  For Aircraft Gross Weights between %7.1f lb and %7.1f lb:\n",
			AFT_CG_BRKGW, MAX_GROSS);
	printf("    AFT CG Limit moves linearly from %6.2f\" to %6.2f\".\n",
			AFT_CG_MINGW, AFT_CG_MAXGW);
	printf("===============================================================\n");

	/* Section 2 - Gather Data for CG Calculation ----------------------------*/

	BLANKLINE;
	printf("===============================================================\n");
	printf("Data Entry for Weight and Balance Compution:\n");
	printf("NOTES:\n");
	printf("  1) Enter all weights in pounds.\n");
	printf("  2) Enter all locations in inches aft of the datum.\n");
	BLANKLINE;
	printf("Aircraft Empty Weight:\n");
	printf("  Enter the weight: ......");
	scanf("%lf", &empty_wt);
	printf("  Enter the location:.....");
	scanf("%lf", &empty_cg);
	BLANKLINE;
	printf("Fuel\n");
	printf("  Enter the weight: ......");
	scanf("%lf", &fuel_wt);
	printf("  Enter the location:.....");
	scanf("%lf", &fuel_cg);
	BLANKLINE;
	printf("Front Seat Occupants:\n");
	printf("  Enter the weight: ......");
	scanf("%lf", &frontpax_wt);
	printf("  Enter the location:.....");
	scanf("%lf", &frontpax_cg);
	BLANKLINE;
	printf("Rear Seat Occupants:\n");
	printf("  Enter the weight: ......");
	scanf("%lf", &rearpax_wt);
	printf("  Enter the location:.....");
	scanf("%lf", &rearpax_cg);
	BLANKLINE;
	printf("Baggage Area Contents:\n");
	printf("  Enter the weight: ......");
	scanf("%lf", &baggage_wt);
	printf("  Enter the location:.....");
	scanf("%lf", &baggage_cg);
	BLANKLINE;
	printf("Combined Miscellaneous Items:\n");
	printf("  Enter the weight: ......");
	scanf("%lf", &misc_wt);
	printf("  Enter the location:.....");
	scanf("%lf", &misc_cg);
	printf("===============================================================\n");

	/* Section 3 - Compute and output the Loading Table ----------------------*/

	/* Total Up the individual item weights */
	gross_wt = gross_mom = 0.0;
	gross_wt += empty_wt;
	gross_wt += fuel_wt;
	gross_wt += frontpax_wt;
	gross_wt += rearpax_wt;
	gross_wt += baggage_wt;
	gross_wt += misc_wt;

	/* Total Up the individual item moments */
	gross_mom = 0.0;
	gross_mom += empty_wt*empty_cg;
	gross_mom += fuel_wt*fuel_cg;
	gross_mom += frontpax_wt*frontpax_cg;
	gross_mom += rearpax_wt*rearpax_cg;
	gross_mom += baggage_wt*baggage_cg;
	gross_mom += misc_wt*misc_cg;

	/* Compute the total CG of all the items */
	gross_cg = gross_mom / gross_wt;

	/* Output the Loading Table */
	BLANKLINE;
	printf("===============================================================\n");
	printf("AIRCRAFT LOADING TABLE\n");
	printf("Aircraft Type: %s\n", AIRCRAFT_TYPE);
	printf("===============================================================\n");
	printf("ITEM               WEIGHT (lbs)   ARM (in)     MOMENT (in-lbs)\n");
	printf("Empty Weight     %8.1f     %7.2f      %10.2f\n",
				empty_wt, empty_cg, empty_wt*empty_cg);
	printf("Fuel             %8.1f     %7.2f      %10.2f\n",
				fuel_wt, fuel_cg, fuel_wt*fuel_cg);
	printf("Front Occupants  %8.1f     %7.2f      %10.2f\n",
				frontpax_wt, frontpax_cg, frontpax_wt*frontpax_cg);
	printf("Rear  Occupants  %8.1f     %7.2f      %10.2f\n",
				rearpax_wt, rearpax_cg, rearpax_wt*rearpax_cg);
	printf("Baggage Area     %8.1f     %7.2f      %10.2f\n",
				baggage_wt, baggage_cg, baggage_wt*baggage_cg);
	printf("Miscellaneous    %8.1f     %7.2f      %10.2f\n",
				misc_wt, misc_cg, misc_wt*misc_cg);
	printf("===============================================================\n");
	printf("TOTAL             %7.1f      %6.2f       %9.2f\n",
				gross_wt, gross_cg, gross_mom);
	printf("===============================================================\n");
	BLANKLINE;

	/* Section 3 - Compute and output the CG Limits --------------------------*/

	/* Compute FWD CG Limit assuming it is on the sloped portion */
	dx = (FWD_CG_MAXGW - FWD_CG_MINGW);
	dy = (MAX_GROSS - FWD_CG_BRKGW);
	fwd_cg = FWD_CG_MINGW + (gross_wt - FWD_CG_BRKGW)*(dx/dy);

	/* Compute AFT CG Limit assuming it is on the sloped portion */
	dx = (AFT_CG_MAXGW - AFT_CG_MINGW);
	dy = (MAX_GROSS - AFT_CG_BRKGW);
	aft_cg = AFT_CG_MINGW + (gross_wt - AFT_CG_BRKGW)*(dx/dy);

	printf("===============================================================\n");
	printf("Your computed CG is %5.2f\" at a gross weight of %6.1flb.\n",
			gross_cg, gross_wt);
	BLANKLINE;
	printf("*** Use only those lines below whose \"if\" clause is true. ***\n");
	BLANKLINE;
	printf("MAX GROSS WEIGHT\n");
	printf("If (%6.1f lb > %6.1f lb): ", gross_wt, MAX_GROSS);
	printf("Aircraft is over max gross weight.\n");
	BLANKLINE;
	printf("FWD CG LIMIT\n");
	printf("If (%6.1f lb <= %6.1f lb <= %6.1f): ", MIN_GROSS, gross_wt, FWD_CG_BRKGW);
	printf("FWD CG LIMIT = %5.2f\"\n", FWD_CG_MINGW);
	printf("If (%6.1f lb <= %6.1f lb <= %6.1f): ", FWD_CG_BRKGW, gross_wt, MAX_GROSS);
	printf("FWD CG LIMIT = %5.2f\"\n", fwd_cg);
	BLANKLINE;
	printf("AFT CG LIMIT\n");
	printf("If (%6.1f lb <= %6.1f lb <= %6.1f): ", MIN_GROSS, gross_wt, AFT_CG_BRKGW);
	printf("AFT CG LIMIT = %5.2f\"\n", AFT_CG_MINGW);
	printf("If (%6.1f lb <= %6.1f lb <= %6.1f): ", AFT_CG_BRKGW, gross_wt, MAX_GROSS);
	printf("AFT CG LIMIT = %5.2f\"\n", aft_cg);
	printf("===============================================================\n");
	BLANKLINE;
	
	/* End of Program --------------------------------------------------------*/

	/* Pause for User to Hit Return */

	while( '\n' != getchar() );    /* Clear all characters until a CR */
	printf("Program Execution Finished - Hit 'RETURN' or 'ENTER' to exit program: ");
	getchar();  

	return(0);
}