Datcom by Holy Cows, Inc.
Home Demo videos Buy/Download FAQ
Questions
before you buy? Email Bill at
datcom@holycows.net
One user attempted to install Datcom+ Pro on
a MacBook running a parallel desktop with Windows 7, and it did not work, so
this configuration is NOT SUGGESTED.
A user has reported that it works fine under
Windows 11.
NO SALES TO
CHINA, TAIWAN OR CHINESE CITIZENS, SORRY
NO SALES TO
RUSSIA, OR RUSSIAN CITIZENS, SORRY
To purchase a licensed copy of the Datcom+
Pro package, follow these instructions
1. Download the RequestDatcomLicense program from this link.
2. Run this program on the
computer that you will be running Datcom+ Pro on. THE LICENSE CANNOT BE
TRANSFERRED TO ANOTHER COMPUTER. This program collects various bits of
information about your computer in order to generate a license. The file Datcom.req
will be generated in a folder Datcom on your desktop. Email this file to
datcom@holycows.net
3. Purchase the license through
PayPal, using the same email address used when the license request file is
sent. Price is $29 US. PayPal will do the conversion for you. Please note that
there will be ABSOULTELY NO REFUNDS. Note: The PayPal page takes a while to
load. It’s their fault, not mine. To purchase more than one license, click on
the Buy Now button below, then on
the PayPal site, change the quantity to the number that you want to purchase.
1 Datcom license
4. A new license file will be
generated for your computer and sent via email back to you. Generally this
license file will be returned within 24 hours, 7 days a week, usually in much
less time. I’m usually at my computer from 7am to 10 pm Eastern Time (United
States). A link to the Datcom+ Pro package will also be
sent.
5. Install the Datcom+ Pro
installation package as well as the license package.
FREE VERSIONS
The free version is still available. It has
not been updated with features of the Datcom+ Pro version. I have
no way of generating a new distribution package without a LOT of work, and I’m
not interested in doing that right now. It is recommended that you view the
tutorial videos to see just how easy it is to use the new Datcom+ Pro.
You will see how powerful this new package is, and the time saved over the free
version. You will find that you are more efficient with the Datcom+ Pro
package than with the free version.
Downloads here:
Once installed, to run the Datcom+ or Datcom+
Pro program, you just double-click on one of the Datcom Input Files (with .dcm
extension) in the Examples directory. If you just try to run the digdat.exe
program alone, it will not run correctly, and give you error messages such as
“open: No such file or directory” and “apparent state: unit 5 named
for005.dat”. This may also cause global warming.
B737 model
warning: This model came from the NASA reports on
Datcom from the 1970’s Their model is garbage. The wing airfoil is nowhere
close to correct. While finding the exact airfoil is not possible, you can
surely find something better than this symmetric airfoil.
There is a problem running the freeware
program Datcom+ under Windows 10/11. This hack should resolve the
issue. Note, this is only work if there is NOT A SPACE IN YOUR USER NAME. For
example, if your username is Joe, the path should be “c:\Users\Joe\Datcom\bin”.
If your username is Joe Smith and the path is “C:\Users\Joe Smith\Datcom\bin”,
this hack will NOT work. There is an untested solution to that below.
If you DO NOT have a space in your username,
follow these steps:
1.
Change the environment variable DATCOMROOT by clicking on the search
box, and typing in “environment variables”. Click on “edit the system environment
variables. Click on the Environment Variables box. Edit DATCOMROOT and remove
the double quotes at the beginning and end. Click “ok” twice.
2.
In the Datcom\bin directory on your desktop, edit the Datcom.bat
file. On lines 14-16, remove the double-quote (“) marks, so that the entries
look like this
set
PREDAT_PROGRAM=predat
set
DATCOM_PROGRAM=digdat
set
DATCOM_MODELER_PROGRAM=datcom-modeler
3.
You should be able to run the programs now.
If you have a space in your username, you might try this. I
haven’t tried it, so I don’t know if it will work. Create a new username
without a space in the username, such as Datcom. Install the Datcom+ program as
that user, and follow the instructions above. It should work for that new user,
and potentially it will then work for your normal username with a space in it.
I have not tried this, so I don’t know if it will work.
These are the PDF files of
the original Datcom manual, 3070 pages of equations and methods that the
Digital Datcom program is based on. Not all of the paper manual is represented
in the computer program.
DATCOM
complete manual from 1978 (3070 pages, 76 Meg)
Or, you can download just the sections that you are
interested in, below:
Section_6_High_Lift_&_Control-2.pdf