Are you sure that you need to edit all of the aircraft?

the only reason I know of to even get into the aircraft.cfg file is to get the title of the aircraft to add it to the aircraft.txt file

have you looked at the readme that comes with traffic tools? It is very helpful, in that it tells you how to add aircraft pretty easily. 

here is the portion of the readme that tells you how to add aircraft to the aircraft.txt file.

20. Aircraft...txt File
This is one of the three source files that the compiler needs to create a traffic file. It is a list of all the aircraft that are referenced by AI flight plans (see the FlightPlans...txt file).

Just adding a new aircraft to this list won’t automatically make it appear as an AI aircraft, there have to be flight plans that use that aircraft.

Not all add-on aircraft work well as AI aircraft. Before adding new aircraft it is strongly recommended that you read the section Guidelines for Adding Aircraft.

You can substitute a new aircraft for one of the existing ones and it will automatically appear as AI traffic because there are already flight plans for that aircraft. If you do this ensure that you substitute aircraft of roughly the same class. Flight plans specify the cruising altitude and trip time, so if you substitute a Cessna 182 for a Boeing 777, the Cessna will struggle to try to reach an impossible altitude, and won’t be able to complete the route in the allotted time so it may just disappear at one point or another. Similarly replacing a C182 with a 777 will result in the 777 flying unrealistically low, and it won’t have a ‘heavy’ gate at smaller airports so it may not even appear, or it may just disappear on landing.

Aircraft are referenced by flight plans using a tag that begins with "AC#", such as AC#32 for a DeHavilland Dash-8. If you substitute an aircraft, keep the same tag so the flight plans will point to the new aircraft.

If you want to increase the number of aircraft models beyond the existing thirty or forty, you will have to either create new flight plans for those aircraft, or go through the flight plan file and substitute those aircraft into some existing flight plans.

There is no obvious limit to the number of aircraft that can be added, other than the limit of 65535 tag numbers. FS may have some internal limit but it is more likely limited only by memory and system performance considerations.

Here are a few typical lines from the Aircraft.txt file. Each line specifies a different aircraft or a different paint scheme of the same aircraft:

   AC#1,200,"Beech Baron 58"
   AC#2,315,"Beech King Air 350"
   AC#3,477,"Boeing 737-400"
   AC#4,477,"Boeing 737-400 Paint1"
   AC#5,477,"Boeing 737-400 Paint2"
   AC#6,477,"Boeing 737-400 Paint3"
   AC#7,477,"Boeing 737-400 Paint4"

Here is a line spread out, with a description of each field:

   AC#4  ,     477  ,     "Boeing 737-400 Paint1"
     |          |               |
   Aircraft   Cruise      Aircraft title
    tag       speed

Aircraft tag:
This is used strictly by the compiler. Aircraft are referenced by this tag in the flight plan file, so for example if tag AC#4 is specified in a flight plan there must be a corresponding aircraft tagged AC#4 in this list. You can add any tag numbers you want, as long they are prefixed by "AC#" and are not already used. The number must be less than 65536. The same aircraft can be referenced in different sets of source files and they do not have to use the same number.

Cruise speed:
This is the cruise speed (TAS) given in the aircraft specifications. It can be found in aircraft manuals or other reference material. Note that this number does not determine the actual cruise speed of AI aircraft, that is based on a cruise speed parameter included in the aircraft model’s aircraft.cfg file. This number is used only by the compiler to compute the trip time for the flight so it can come up with arrival times and sector mapping for flight plans that don’t use fixed arrival times.

Aircraft title:
This is how FS2002 finds an aircraft model when it wants to make it appear as AI. This title must exactly match a title in the aircraft.cfg file for one of the installed aircraft. It will appear in a line such as title = Boeing 737-400 Paint1. Note that each aircraft can have several different ‘skins’, hence the Paint1, Paint2, etc. suffixes. Each of these will have separate title lines in the same aircraft.cfg file. These different paint schemes often represent different airlines.