Here is A.X.E. - a free HEX editor that many folks at SWWISA use... 

Hex Editing campaign.dat

This info was originally compiled by Sygrod and is available here:

http://home.golden.net/~ksharman/rb/Main.html

However thanks to the further efforts of Mark Hutchinson, we can see the advantages to HEX editing this important file.

First start by grapping a good HEX editor like A.X.E. (here), then download the instruction file for editing campaign.dat.  Mark explains in detail how to correct the '3 Ace scheme' glitch and quite a few other topics he came across.

I would offer this as a layout on this page, but it is better-off left in the form Mark sent it to me.

- Campaign Hexing

Changing Red Baron to a Higher Screen Resolution - Jammer

It's very simple. Look here:

This is a shot of rbprefs.dat in the hex editor AXE. The first red box shows you were the width is stored. 00 05 means 0500 hex. The last two digits are stored first. 0500 hex = 1280 decimal. The second box is the height. 00 04 = 0400 hex = 1024 decimal.

To change you resolution to 1280x960, you would first need to translate 960 into hex: 03C0. Then, edit the second box to read: "C0 03".

For 1600x1200 it's:
1600 = 4006
1200 = B004

HEX Editing the fog distance - by Geoman

I don't know if anyone knows about this but here's a tip to move the fog further at the distance and increase the Terrain Range:

Set all Graphics options to Max. Open rbprefs.dat (in the Data folder) with a hex editor and change the 9th byte from 64 to FF. You can also change the 10th byte from 0 to 1 or 2 (any more and the game will crash!)

Now when you fly, the fog will appear far in the distance and you will enjoy your flight and the new terrain graphics!

NOTE: Always backup your original files first and note that the above change will have a drastic effect on your frame rates!!!