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Importing from USAF Digital DATCOM Files

This example shows how to bring United States Air Force (USAF) Digital DATCOM files into the MATLAB® environment using the Aerospace Toolbox™ software.

Example USAF Digital DATCOM File

Here's a sample input file for USAF Digital DATCOM for a wing-body-horizontal tail-vertical tail configuration running over 5 alphas, 2 Mach numbers, and 2 altitudes and calculating static and dynamic derivatives:

type astdatcom.in
 $FLTCON NMACH=2.0,MACH(1)=0.1,0.2$
 $FLTCON NALT=2.0,ALT(1)=5000.0,8000.0$                        
 $FLTCON NALPHA=5.,ALSCHD(1)=-2.0,0.0,2.0,    
  ALSCHD(4)=4.0,8.0,LOOP=2.0$
 $OPTINS SREF=225.8,CBARR=5.75,BLREF=41.15$                                      
 $SYNTHS XCG=7.08,ZCG=0.0,XW=6.1,ZW=-1.4,ALIW=1.1,XH=20.2,                      
   ZH=0.4,ALIH=0.0,XV=21.3,ZV=0.0,VERTUP=.TRUE.$                                        
 $BODY NX=10.0,                          
   X(1)=-4.9,0.0,3.0,6.1,9.1,13.3,20.2,23.5,25.9,                       
   R(1)=0.0,1.0,1.75,2.6,2.6,2.6,2.0,1.0,0.0$                     
 $WGPLNF CHRDTP=4.0,SSPNE=18.7,SSPN=20.6,CHRDR=7.2,SAVSI=0.0,CHSTAT=0.25,   
   TWISTA=-1.1,SSPNDD=0.0,DHDADI=3.0,DHDADO=3.0,TYPE=1.0$                         
NACA-W-6-64A412
 $HTPLNF CHRDTP=2.3,SSPNE=5.7,SSPN=6.625,CHRDR=0.25,SAVSI=11.0,                 
   CHSTAT=1.0,TWISTA=0.0,TYPE=1.0$                                               
NACA-H-4-0012
 $VTPLNF CHRDTP=2.7,SSPNE=5.0,SSPN=5.2,CHRDR=5.3,SAVSI=31.3,                 
   CHSTAT=0.25,TWISTA=0.0,TYPE=1.0$                                               
NACA-V-4-0012
CASEID SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG 
DAMP
NEXT CASE                                                                    

Here's the output file generated by USAF Digital DATCOM for the same wing-body-horizontal tail-vertical tail configuration running over 5 alphas, 2 Mach numbers, and 2 altitudes:

type astdatcom.out
 THIS SOFTWARE AND ANY ACCOMPANYING DOCUMENTATION
 IS RELEASED "AS IS".  THE U.S. GOVERNMENT MAKES NO
 WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, CONCERNING
 THIS SOFTWARE AND ANY ACCOMPANYING DOCUMENTATION,
 INCLUDING, WITHOUT LIMITATION, ANY WARRANTIES OF
 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 IN NO EVENT WILL THE U.S. GOVERNMENT BE LIABLE FOR ANY
 DAMAGES, INCLUDING LOST PROFITS, LOST SAVINGS OR OTHER
 INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE 
 USE, OR INABILITY TO USE, THIS SOFTWARE OR ANY
 ACCOMPANYING DOCUMENTATION, EVEN IF INFORMED IN ADVANCE
 OF THE POSSIBILITY OF SUCH DAMAGES.








                                        ****************************************************
                                        *    USAF STABILITY AND CONTROL  DIGITAL DATCOM    *
                                        *    PROGRAM REV. JAN 96   DIRECT INQUIRIES TO:    *
                                        *   WRIGHT LABORATORY  (WL/FIGC)  ATTN: W. BLAKE   *
                                        *         WRIGHT PATTERSON AFB, OHIO  45433        *
                                        *    PHONE (513) 255-6764,   FAX (513) 258-4054    *
                                        ****************************************************
1                         CONERR - INPUT ERROR CHECKING
0 ERROR CODES - N* DENOTES THE NUMBER OF OCCURENCES OF EACH ERROR
0 A - UNKNOWN VARIABLE NAME
0 B - MISSING EQUAL SIGN FOLLOWING VARIABLE NAME
0 C - NON-ARRAY VARIABLE HAS AN ARRAY ELEMENT DESIGNATION - (N)
0 D - NON-ARRAY VARIABLE HAS MULTIPLE VALUES ASSIGNED
0 E - ASSIGNED VALUES EXCEED ARRAY DIMENSION
0 F - SYNTAX ERROR

0******************************  INPUT DATA CARDS  ******************************

  $FLTCON NMACH=2.0,MACH(1)=0.1,0.2$                                             
  $FLTCON NALT=2.0,ALT(1)=5000.0,8000.0$                                         
  $FLTCON NALPHA=5.,ALSCHD(1)=-2.0,0.0,2.0,                                      
   ALSCHD(4)=4.0,8.0,LOOP=2.0$                                                   
  $OPTINS SREF=225.8,CBARR=5.75,BLREF=41.15$                                     
  $SYNTHS XCG=7.08,ZCG=0.0,XW=6.1,ZW=-1.4,ALIW=1.1,XH=20.2,                      
    ZH=0.4,ALIH=0.0,XV=21.3,ZV=0.0,VERTUP=.TRUE.$                                
  $BODY NX=10.0,                                                                 
    X(1)=-4.9,0.0,3.0,6.1,9.1,13.3,20.2,23.5,25.9,                               
    R(1)=0.0,1.0,1.75,2.6,2.6,2.6,2.0,1.0,0.0$                                   
  $WGPLNF CHRDTP=4.0,SSPNE=18.7,SSPN=20.6,CHRDR=7.2,SAVSI=0.0,CHSTAT=0.25,       
    TWISTA=-1.1,SSPNDD=0.0,DHDADI=3.0,DHDADO=3.0,TYPE=1.0$                       
 NACA-W-6-64A412                                                                 
  $HTPLNF CHRDTP=2.3,SSPNE=5.7,SSPN=6.625,CHRDR=0.25,SAVSI=11.0,                 
    CHSTAT=1.0,TWISTA=0.0,TYPE=1.0$                                              
 NACA-H-4-0012                                                                   
  $VTPLNF CHRDTP=2.7,SSPNE=5.0,SSPN=5.2,CHRDR=5.3,SAVSI=31.3,                    
    CHSTAT=0.25,TWISTA=0.0,TYPE=1.0$                                             
 NACA-V-4-0012                                                                   
 CASEID SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG        
 DAMP                                                                            
 NEXT CASE                                                                       
1          THE FOLLOWING IS A LIST OF ALL INPUT CARDS FOR THIS CASE.
0
  $FLTCON NMACH=2.0,MACH(1)=0.1,0.2$                                             
  $FLTCON NALT=2.0,ALT(1)=5000.0,8000.0$                                         
  $FLTCON NALPHA=5.,ALSCHD(1)=-2.0,0.0,2.0,                                      
   ALSCHD(4)=4.0,8.0,LOOP=2.0$                                                   
  $OPTINS SREF=225.8,CBARR=5.75,BLREF=41.15$                                     
  $SYNTHS XCG=7.08,ZCG=0.0,XW=6.1,ZW=-1.4,ALIW=1.1,XH=20.2,                      
    ZH=0.4,ALIH=0.0,XV=21.3,ZV=0.0,VERTUP=.TRUE.$                                
  $BODY NX=10.0,                                                                 
    X(1)=-4.9,0.0,3.0,6.1,9.1,13.3,20.2,23.5,25.9,                               
    R(1)=0.0,1.0,1.75,2.6,2.6,2.6,2.0,1.0,0.0$                                   
  $WGPLNF CHRDTP=4.0,SSPNE=18.7,SSPN=20.6,CHRDR=7.2,SAVSI=0.0,CHSTAT=0.25,       
    TWISTA=-1.1,SSPNDD=0.0,DHDADI=3.0,DHDADO=3.0,TYPE=1.0$                       
 NACA-W-6-64A412                                                                 
  $HTPLNF CHRDTP=2.3,SSPNE=5.7,SSPN=6.625,CHRDR=0.25,SAVSI=11.0,                 
    CHSTAT=1.0,TWISTA=0.0,TYPE=1.0$                                              
 NACA-H-4-0012                                                                   
  $VTPLNF CHRDTP=2.7,SSPNE=5.0,SSPN=5.2,CHRDR=5.3,SAVSI=31.3,                    
    CHSTAT=0.25,TWISTA=0.0,TYPE=1.0$                                             
 NACA-V-4-0012                                                                   
 CASEID SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG        
 DAMP                                                                            
 NEXT CASE                                                                       
0 INPUT DIMENSIONS ARE IN FT, SCALE FACTOR IS 1.0000

1                             AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM   
                                                        WING SECTION DEFINITION
0                                 IDEAL ANGLE OF ATTACK =   0.00000 DEG.

                              ZERO LIFT ANGLE OF ATTACK =  -3.09292 DEG.

                                 IDEAL LIFT COEFFICIENT =   0.40000

                  ZERO LIFT PITCHING MOMENT COEFFICIENT =  -0.08719

                             MACH ZERO LIFT-CURVE-SLOPE =   0.09654 /DEG.

                                    LEADING EDGE RADIUS =   0.00993 FRACTION CHORD

                              MAXIMUM AIRFOIL THICKNESS =   0.12000 FRACTION CHORD

                                                DELTA-Y =   2.46808 PERCENT CHORD


0                         MACH= 0.1000 LIFT-CURVE-SLOPE =   0.09693 /DEG.      XAC =   0.26404
0                         MACH= 0.2000 LIFT-CURVE-SLOPE =   0.09811 /DEG.      XAC =   0.26457
1                             AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM   
                                                   HORIZONTAL TAIL SECTION DEFINITION
0                                 IDEAL ANGLE OF ATTACK =   0.00000 DEG.

                              ZERO LIFT ANGLE OF ATTACK =   0.00000 DEG.

                                 IDEAL LIFT COEFFICIENT =   0.00000

                  ZERO LIFT PITCHING MOMENT COEFFICIENT =   0.00000

                             MACH ZERO LIFT-CURVE-SLOPE =   0.09596 /DEG.

                                    LEADING EDGE RADIUS =   0.01587 FRACTION CHORD

                              MAXIMUM AIRFOIL THICKNESS =   0.12000 FRACTION CHORD

                                                DELTA-Y =   3.16898 PERCENT CHORD


0                         MACH= 0.1000 LIFT-CURVE-SLOPE =   0.09636 /DEG.      XAC =   0.25854
0                         MACH= 0.2000 LIFT-CURVE-SLOPE =   0.09761 /DEG.      XAC =   0.25881
1                             AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM   
                                                    VERTICAL TAIL SECTION DEFINITION
0                                 IDEAL ANGLE OF ATTACK =   0.00000 DEG.

                              ZERO LIFT ANGLE OF ATTACK =   0.00000 DEG.

                                 IDEAL LIFT COEFFICIENT =   0.00000

                  ZERO LIFT PITCHING MOMENT COEFFICIENT =   0.00000

                             MACH ZERO LIFT-CURVE-SLOPE =   0.09596 /DEG.

                                    LEADING EDGE RADIUS =   0.01587 FRACTION CHORD

                              MAXIMUM AIRFOIL THICKNESS =   0.12000 FRACTION CHORD

                                                DELTA-Y =   3.16898 PERCENT CHORD


0                         MACH= 0.1000 LIFT-CURVE-SLOPE =   0.09636 /DEG.      XAC =   0.25854
0                         MACH= 0.2000 LIFT-CURVE-SLOPE =   0.09761 /DEG.      XAC =   0.25881
1                               AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM
                                         CHARACTERISTICS AT ANGLE OF ATTACK AND IN SIDESLIP
                                        WING-BODY-VERTICAL TAIL-HORIZONTAL TAIL CONFIGURATION
                                 SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG
 
 -----------------------  FLIGHT CONDITIONS  ------------------------           --------------  REFERENCE DIMENSIONS  ------------
  MACH    ALTITUDE   VELOCITY    PRESSURE    TEMPERATURE     REYNOLDS             REF.      REFERENCE LENGTH   MOMENT REF. CENTER
 NUMBER                                                       NUMBER              AREA       LONG.     LAT.     HORIZ      VERT
             FT       FT/SEC     LB/FT**2       DEG R         1/FT               FT**2        FT        FT        FT        FT
0 0.100    5000.00     109.70   1.7609E+03     500.843     6.1507E+05           225.800      5.750    41.150     7.080     0.000
0                                                               -------------------DERIVATIVE (PER DEGREE)-------------------
0 ALPHA     CD       CL       CM       CN       CA       XCP        CLA          CMA          CYB          CNB          CLB
0
   -2.0    0.032    0.113   -0.0340   0.112    0.035   -0.304    8.926E-02   -2.105E-02   -3.458E-03    9.142E-04   -6.161E-04
    0.0    0.035    0.296   -0.0752   0.296    0.035   -0.254    9.350E-02   -2.034E-02                             -6.205E-04
    2.0    0.042    0.487   -0.1153   0.488    0.025   -0.236    9.732E-02   -1.971E-02                             -6.268E-04
    4.0    0.052    0.685   -0.1541   0.687    0.004   -0.224    1.005E-01   -1.927E-02                             -6.349E-04
    8.0    0.084    1.098   -0.2304   1.099   -0.069   -0.210    1.059E-01   -1.890E-02                             -6.554E-04
0                                    ALPHA     Q/QINF    EPSLON  D(EPSLON)/D(ALPHA)
0
                                     -2.0      1.000      0.953        0.571
                                      0.0      1.000      2.094        0.583
                                      2.0      1.000      3.284        0.606
                                      4.0      1.000      4.520        0.610
                                      8.0      1.000      6.897        0.594
1                               AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM
                                                         DYNAMIC DERIVATIVES
                                        WING-BODY-VERTICAL TAIL-HORIZONTAL TAIL CONFIGURATION
                                 SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG
 
 -----------------------  FLIGHT CONDITIONS  ------------------------           --------------  REFERENCE DIMENSIONS  ------------
  MACH    ALTITUDE   VELOCITY    PRESSURE    TEMPERATURE     REYNOLDS             REF.      REFERENCE LENGTH   MOMENT REF. CENTER
 NUMBER                                                       NUMBER              AREA       LONG.     LAT.     HORIZ      VERT
             FT       FT/SEC     LB/FT**2       DEG R         1/FT               FT**2        FT        FT        FT        FT
0 0.100    5000.00     109.70   1.7609E+03     500.843     6.1507E+05           225.800      5.750    41.150     7.080     0.000
                                                    DYNAMIC DERIVATIVES (PER DEGREE)
0           -------PITCHING-------    -----ACCELERATION------    --------------ROLLING--------------    --------YAWING--------
0   ALPHA       CLQ          CMQ           CLAD         CMAD         CLP          CYP          CNP          CNR          CLR
0
    -2.00    9.739E-02   -8.918E-02     1.874E-02   -4.247E-02   -7.824E-03   -1.516E-03   -1.498E-04   -1.059E-03    6.334E-04
     0.00                               1.913E-02   -4.336E-02   -8.226E-03   -1.649E-03   -4.034E-04   -1.068E-03    1.240E-03
     2.00                               1.991E-02   -4.512E-02   -8.599E-03   -1.792E-03   -6.631E-04   -1.073E-03    1.878E-03
     4.00                               2.003E-02   -4.540E-02   -8.890E-03   -1.942E-03   -9.290E-04   -1.073E-03    2.542E-03
     8.00                               1.952E-02   -4.424E-02   -9.387E-03   -2.262E-03   -1.479E-03   -1.060E-03    3.926E-03
1                               AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM
                                         CHARACTERISTICS AT ANGLE OF ATTACK AND IN SIDESLIP
                                        WING-BODY-VERTICAL TAIL-HORIZONTAL TAIL CONFIGURATION
                                 SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG
 
 -----------------------  FLIGHT CONDITIONS  ------------------------           --------------  REFERENCE DIMENSIONS  ------------
  MACH    ALTITUDE   VELOCITY    PRESSURE    TEMPERATURE     REYNOLDS             REF.      REFERENCE LENGTH   MOMENT REF. CENTER
 NUMBER                                                       NUMBER              AREA       LONG.     LAT.     HORIZ      VERT
             FT       FT/SEC     LB/FT**2       DEG R         1/FT               FT**2        FT        FT        FT        FT
0 0.200    5000.00     219.39   1.7609E+03     500.843     1.2301E+06           225.800      5.750    41.150     7.080     0.000
0                                                               -------------------DERIVATIVE (PER DEGREE)-------------------
0 ALPHA     CD       CL       CM       CN       CA       XCP        CLA          CMA          CYB          CNB          CLB
0
   -2.0    0.028    0.114   -0.0335   0.113    0.032   -0.297    9.000E-02   -2.124E-02   -3.465E-03    8.781E-04   -6.226E-04
    0.0    0.031    0.298   -0.0751   0.298    0.031   -0.252    9.421E-02   -2.051E-02                             -6.270E-04
    2.0    0.038    0.491   -0.1155   0.492    0.021   -0.235    9.800E-02   -1.987E-02                             -6.332E-04
    4.0    0.048    0.690   -0.1546   0.692    0.000   -0.223    1.011E-01   -1.943E-02                             -6.413E-04
    8.0    0.081    1.105   -0.2316   1.106   -0.074   -0.209    1.065E-01   -1.906E-02                             -6.614E-04
0                                    ALPHA     Q/QINF    EPSLON  D(EPSLON)/D(ALPHA)
0
                                     -2.0      1.000      0.957        0.573
                                      0.0      1.000      2.103        0.585
                                      2.0      1.000      3.297        0.609
                                      4.0      1.000      4.537        0.612
                                      8.0      1.000      6.923        0.596
1                               AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM
                                                         DYNAMIC DERIVATIVES
                                        WING-BODY-VERTICAL TAIL-HORIZONTAL TAIL CONFIGURATION
                                 SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG
 
 -----------------------  FLIGHT CONDITIONS  ------------------------           --------------  REFERENCE DIMENSIONS  ------------
  MACH    ALTITUDE   VELOCITY    PRESSURE    TEMPERATURE     REYNOLDS             REF.      REFERENCE LENGTH   MOMENT REF. CENTER
 NUMBER                                                       NUMBER              AREA       LONG.     LAT.     HORIZ      VERT
             FT       FT/SEC     LB/FT**2       DEG R         1/FT               FT**2        FT        FT        FT        FT
0 0.200    5000.00     219.39   1.7609E+03     500.843     1.2301E+06           225.800      5.750    41.150     7.080     0.000
                                                    DYNAMIC DERIVATIVES (PER DEGREE)
0           -------PITCHING-------    -----ACCELERATION------    --------------ROLLING--------------    --------YAWING--------
0   ALPHA       CLQ          CMQ           CLAD         CMAD         CLP          CYP          CNP          CNR          CLR
0
    -2.00    9.840E-02   -8.993E-02     1.900E-02   -4.307E-02   -7.877E-03   -1.525E-03   -1.499E-04   -1.057E-03    6.448E-04
     0.00                               1.940E-02   -4.398E-02   -8.276E-03   -1.659E-03   -4.038E-04   -1.066E-03    1.264E-03
     2.00                               2.018E-02   -4.574E-02   -8.646E-03   -1.802E-03   -6.637E-04   -1.070E-03    1.915E-03
     4.00                               2.030E-02   -4.602E-02   -8.934E-03   -1.953E-03   -9.297E-04   -1.070E-03    2.593E-03
     8.00                               1.978E-02   -4.483E-02   -9.423E-03   -2.273E-03   -1.479E-03   -1.057E-03    4.003E-03
1                               AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM
                                         CHARACTERISTICS AT ANGLE OF ATTACK AND IN SIDESLIP
                                        WING-BODY-VERTICAL TAIL-HORIZONTAL TAIL CONFIGURATION
                                 SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG
 
 -----------------------  FLIGHT CONDITIONS  ------------------------           --------------  REFERENCE DIMENSIONS  ------------
  MACH    ALTITUDE   VELOCITY    PRESSURE    TEMPERATURE     REYNOLDS             REF.      REFERENCE LENGTH   MOMENT REF. CENTER
 NUMBER                                                       NUMBER              AREA       LONG.     LAT.     HORIZ      VERT
             FT       FT/SEC     LB/FT**2       DEG R         1/FT               FT**2        FT        FT        FT        FT
0 0.100    8000.00     108.52   1.5721E+03     490.151     5.6457E+05           225.800      5.750    41.150     7.080     0.000
0                                                               -------------------DERIVATIVE (PER DEGREE)-------------------
0 ALPHA     CD       CL       CM       CN       CA       XCP        CLA          CMA          CYB          CNB          CLB
0
   -2.0    0.032    0.113   -0.0340   0.112    0.036   -0.305    8.926E-02   -2.106E-02   -3.458E-03    9.190E-04   -6.161E-04
    0.0    0.035    0.296   -0.0753   0.296    0.035   -0.254    9.350E-02   -2.034E-02                             -6.205E-04
    2.0    0.042    0.487   -0.1154   0.488    0.025   -0.236    9.732E-02   -1.971E-02                             -6.268E-04
    4.0    0.052    0.685   -0.1541   0.687    0.004   -0.224    1.005E-01   -1.927E-02                             -6.349E-04
    8.0    0.085    1.098   -0.2304   1.099   -0.069   -0.210    1.059E-01   -1.891E-02                             -6.554E-04
0                                    ALPHA     Q/QINF    EPSLON  D(EPSLON)/D(ALPHA)
0
                                     -2.0      1.000      0.953        0.571
                                      0.0      1.000      2.094        0.583
                                      2.0      1.000      3.284        0.606
                                      4.0      1.000      4.520        0.610
                                      8.0      1.000      6.897        0.594
1                               AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM
                                                         DYNAMIC DERIVATIVES
                                        WING-BODY-VERTICAL TAIL-HORIZONTAL TAIL CONFIGURATION
                                 SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG
 
 -----------------------  FLIGHT CONDITIONS  ------------------------           --------------  REFERENCE DIMENSIONS  ------------
  MACH    ALTITUDE   VELOCITY    PRESSURE    TEMPERATURE     REYNOLDS             REF.      REFERENCE LENGTH   MOMENT REF. CENTER
 NUMBER                                                       NUMBER              AREA       LONG.     LAT.     HORIZ      VERT
             FT       FT/SEC     LB/FT**2       DEG R         1/FT               FT**2        FT        FT        FT        FT
0 0.100    8000.00     108.52   1.5721E+03     490.151     5.6457E+05           225.800      5.750    41.150     7.080     0.000
                                                    DYNAMIC DERIVATIVES (PER DEGREE)
0           -------PITCHING-------    -----ACCELERATION------    --------------ROLLING--------------    --------YAWING--------
0   ALPHA       CLQ          CMQ           CLAD         CMAD         CLP          CYP          CNP          CNR          CLR
0
    -2.00    9.739E-02   -8.918E-02     1.874E-02   -4.247E-02   -7.824E-03   -1.516E-03   -1.498E-04   -1.060E-03    6.334E-04
     0.00                               1.913E-02   -4.336E-02   -8.226E-03   -1.649E-03   -4.034E-04   -1.069E-03    1.240E-03
     2.00                               1.991E-02   -4.512E-02   -8.599E-03   -1.792E-03   -6.631E-04   -1.073E-03    1.878E-03
     4.00                               2.003E-02   -4.540E-02   -8.890E-03   -1.942E-03   -9.290E-04   -1.074E-03    2.542E-03
     8.00                               1.952E-02   -4.424E-02   -9.387E-03   -2.262E-03   -1.479E-03   -1.061E-03    3.926E-03
1                               AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM
                                         CHARACTERISTICS AT ANGLE OF ATTACK AND IN SIDESLIP
                                        WING-BODY-VERTICAL TAIL-HORIZONTAL TAIL CONFIGURATION
                                 SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG
 
 -----------------------  FLIGHT CONDITIONS  ------------------------           --------------  REFERENCE DIMENSIONS  ------------
  MACH    ALTITUDE   VELOCITY    PRESSURE    TEMPERATURE     REYNOLDS             REF.      REFERENCE LENGTH   MOMENT REF. CENTER
 NUMBER                                                       NUMBER              AREA       LONG.     LAT.     HORIZ      VERT
             FT       FT/SEC     LB/FT**2       DEG R         1/FT               FT**2        FT        FT        FT        FT
0 0.200    8000.00     217.04   1.5721E+03     490.151     1.1291E+06           225.800      5.750    41.150     7.080     0.000
0                                                               -------------------DERIVATIVE (PER DEGREE)-------------------
0 ALPHA     CD       CL       CM       CN       CA       XCP        CLA          CMA          CYB          CNB          CLB
0
   -2.0    0.028    0.114   -0.0335   0.113    0.032   -0.297    9.000E-02   -2.124E-02   -3.465E-03    8.829E-04   -6.226E-04
    0.0    0.031    0.298   -0.0751   0.298    0.031   -0.252    9.421E-02   -2.051E-02                             -6.270E-04
    2.0    0.038    0.491   -0.1156   0.492    0.021   -0.235    9.800E-02   -1.987E-02                             -6.332E-04
    4.0    0.049    0.690   -0.1546   0.692    0.000   -0.223    1.011E-01   -1.943E-02                             -6.413E-04
    8.0    0.081    1.105   -0.2316   1.106   -0.073   -0.209    1.065E-01   -1.906E-02                             -6.614E-04
0                                    ALPHA     Q/QINF    EPSLON  D(EPSLON)/D(ALPHA)
0
                                     -2.0      1.000      0.957        0.573
                                      0.0      1.000      2.103        0.585
                                      2.0      1.000      3.297        0.609
                                      4.0      1.000      4.537        0.612
                                      8.0      1.000      6.923        0.596
1                               AUTOMATED STABILITY AND CONTROL METHODS PER APRIL 1976 VERSION OF DATCOM
                                                         DYNAMIC DERIVATIVES
                                        WING-BODY-VERTICAL TAIL-HORIZONTAL TAIL CONFIGURATION
                                 SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG
 
 -----------------------  FLIGHT CONDITIONS  ------------------------           --------------  REFERENCE DIMENSIONS  ------------
  MACH    ALTITUDE   VELOCITY    PRESSURE    TEMPERATURE     REYNOLDS             REF.      REFERENCE LENGTH   MOMENT REF. CENTER
 NUMBER                                                       NUMBER              AREA       LONG.     LAT.     HORIZ      VERT
             FT       FT/SEC     LB/FT**2       DEG R         1/FT               FT**2        FT        FT        FT        FT
0 0.200    8000.00     217.04   1.5721E+03     490.151     1.1291E+06           225.800      5.750    41.150     7.080     0.000
                                                    DYNAMIC DERIVATIVES (PER DEGREE)
0           -------PITCHING-------    -----ACCELERATION------    --------------ROLLING--------------    --------YAWING--------
0   ALPHA       CLQ          CMQ           CLAD         CMAD         CLP          CYP          CNP          CNR          CLR
0
    -2.00    9.840E-02   -8.993E-02     1.900E-02   -4.307E-02   -7.877E-03   -1.525E-03   -1.499E-04   -1.057E-03    6.448E-04
     0.00                               1.940E-02   -4.398E-02   -8.276E-03   -1.659E-03   -4.038E-04   -1.066E-03    1.264E-03
     2.00                               2.018E-02   -4.574E-02   -8.646E-03   -1.802E-03   -6.637E-04   -1.071E-03    1.915E-03
     4.00                               2.030E-02   -4.602E-02   -8.934E-03   -1.953E-03   -9.297E-04   -1.071E-03    2.593E-03
     8.00                               1.978E-02   -4.483E-02   -9.424E-03   -2.273E-03   -1.479E-03   -1.057E-03    4.003E-03
1          THE FOLLOWING IS A LIST OF ALL INPUT CARDS FOR THIS CASE.
0
1 END OF JOB.

Import Data from DATCOM Files

Use the datcomimport function to bring the Digital DATCOM data into MATLAB.

alldata = datcomimport('astdatcom.out', true, 0);

Examining Imported DATCOM Data

The datcomimport function creates a cell array of structures containing the data from the Digital DATCOM output file.

data = alldata{1}
data = 

        case: 'SKYHOGG BODY-WING-HORIZONTAL TAIL-VERTICAL TAIL CONFIG'
        mach: [0.1000 0.2000]
         alt: [5000 8000]
       alpha: [-2 0 2 4 8]
       nmach: 2
        nalt: 2
      nalpha: 5
       rnnub: []
      hypers: 0
        loop: 2
        sref: 225.8000
        cbar: 5.7500
       blref: 41.1500
         dim: 'ft'
       deriv: 'deg'
      stmach: 0.6000
      tsmach: 1.4000
        save: 0
       stype: []
        trim: 0
        damp: 1
       build: 1
        part: 0
     highsym: 0
     highasy: 0
     highcon: 0
        tjet: 0
      hypeff: 0
          lb: 0
         pwr: 0
        grnd: 0
       wsspn: 18.7000
       hsspn: 5.7000
      ndelta: 0
       delta: []
      deltal: []
      deltar: []
         ngh: 0
      grndht: []
      config: [1x1 struct]
     version: 1976
          cd: [5x2x2 double]
          cl: [5x2x2 double]
          cm: [5x2x2 double]
          cn: [5x2x2 double]
          ca: [5x2x2 double]
         xcp: [5x2x2 double]
         cma: [5x2x2 double]
         cyb: [5x2x2 double]
         cnb: [5x2x2 double]
         clb: [5x2x2 double]
         cla: [5x2x2 double]
       qqinf: [5x2x2 double]
         eps: [5x2x2 double]
    depsdalp: [5x2x2 double]
         clq: [5x2x2 double]
         cmq: [5x2x2 double]
        clad: [5x2x2 double]
        cmad: [5x2x2 double]
         clp: [5x2x2 double]
         cyp: [5x2x2 double]
         cnp: [5x2x2 double]
         cnr: [5x2x2 double]
         clr: [5x2x2 double]

Filling in Missing DATCOM Data

By default, missing data points are set to 99999 and data points are set to NaN where no DATCOM methods exist or where the method is not applicable.

It can be seen in the Digital DATCOM output file and examining the imported data that

$$ C_{Y\beta},$$
$$ C_{n\beta},$$
$$ C_{lq},$$ and
$$ C_{mq}$$

have data only in the first alpha value. Here are the imported data values.

data.cyb
ans(:,:,1) =

   1.0e+04 *

   -0.0000   -0.0000
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999


ans(:,:,2) =

   1.0e+04 *

   -0.0000   -0.0000
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999

data.cnb
ans(:,:,1) =

   1.0e+04 *

    0.0000    0.0000
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999


ans(:,:,2) =

   1.0e+04 *

    0.0000    0.0000
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999

data.clq
ans(:,:,1) =

   1.0e+04 *

    0.0000    0.0000
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999


ans(:,:,2) =

   1.0e+04 *

    0.0000    0.0000
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999

data.cmq
ans(:,:,1) =

   1.0e+04 *

   -0.0000   -0.0000
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999


ans(:,:,2) =

   1.0e+04 *

   -0.0000   -0.0000
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999
    9.9999    9.9999

The missing data points will be filled with the values for the first alpha, since these data points are meant to be used for all alpha values.

aerotab = {'cyb' 'cnb' 'clq' 'cmq'};

for k = 1:length(aerotab)
    for m = 1:data.nmach
        for h = 1:data.nalt
            data.(aerotab{k})(:,m,h) = data.(aerotab{k})(1,m,h);
        end
    end
end

Here are the updated imported data values:

data.cyb
ans(:,:,1) =

   -0.0035   -0.0035
   -0.0035   -0.0035
   -0.0035   -0.0035
   -0.0035   -0.0035
   -0.0035   -0.0035


ans(:,:,2) =

   -0.0035   -0.0035
   -0.0035   -0.0035
   -0.0035   -0.0035
   -0.0035   -0.0035
   -0.0035   -0.0035

data.cnb
ans(:,:,1) =

   1.0e-03 *

    0.9142    0.8781
    0.9142    0.8781
    0.9142    0.8781
    0.9142    0.8781
    0.9142    0.8781


ans(:,:,2) =

   1.0e-03 *

    0.9190    0.8829
    0.9190    0.8829
    0.9190    0.8829
    0.9190    0.8829
    0.9190    0.8829

data.clq
ans(:,:,1) =

    0.0974    0.0984
    0.0974    0.0984
    0.0974    0.0984
    0.0974    0.0984
    0.0974    0.0984


ans(:,:,2) =

    0.0974    0.0984
    0.0974    0.0984
    0.0974    0.0984
    0.0974    0.0984
    0.0974    0.0984

data.cmq
ans(:,:,1) =

   -0.0892   -0.0899
   -0.0892   -0.0899
   -0.0892   -0.0899
   -0.0892   -0.0899
   -0.0892   -0.0899


ans(:,:,2) =

   -0.0892   -0.0899
   -0.0892   -0.0899
   -0.0892   -0.0899
   -0.0892   -0.0899
   -0.0892   -0.0899

Plotting Aerodynamic Coefficients

Plot lift curve, drag polar and pitching moments.

h1 = figure;
figtitle = {'Lift Curve' ''};
for k=1:2
    subplot(2,1,k)
    plot(data.alpha,permute(data.cl(:,k,:),[1 3 2]))
    grid
    ylabel(['Lift Coefficient (Mach =' num2str(data.mach(k)) ')'])
    title(figtitle{k});
end
xlabel('Angle of Attack (deg)')

h2 = figure;
figtitle = {'Drag Polar' ''};
for k=1:2
    subplot(2,1,k)
    plot(permute(data.cd(:,k,:),[1 3 2]),permute(data.cl(:,k,:),[1 3 2]))
    grid
    ylabel(['Lift Coefficient (Mach =' num2str(data.mach(k)) ')'])
    title(figtitle{k})
end
xlabel('Drag Coefficient')

h3 = figure;
figtitle = {'Pitching Moment' ''};
for k=1:2
    subplot(2,1,k)
    plot(permute(data.cm(:,k,:),[1 3 2]),permute(data.cl(:,k,:),[1 3 2]))
    grid
    ylabel(['Lift Coefficient (Mach =' num2str(data.mach(k)) ')'])
    title(figtitle{k})
end
xlabel('Pitching Moment Coefficient')

close(h1,h2,h3);
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