After looking at some names posted in this thread by Marweas and Grey Falcon, and then looking at "Tribal Technology Overview" by Blake Hutchins & Dave Meddish, the name that stands out to me alot that doesn't involve the word "Tribes" is Stormhammer.
It is the spinfusors name.
Stormhammer
Stormhammer Chronicles
Project: Stormhammer
Stormhammer: War is Forever
^These are just some very quick ideas above. Maybe lame to some, but an attempt. Will think about more over next several days.
That name doesn't blow me away but it doesn't seem that outta place at least for a starting working title as the fusor is really the centerpiece weapon in Tribes.
Here is the Description of the spinfusor we know and love:
Spinfusor
The signature weapon of Tribal arsenals, few
warriors are found without a 'discer' equipped.This weapon is an odd hybrid of magnetic and gravitic acceleration technologies. Most warriors call it the "spinfusor" after the ammunition it fires. It is also called the Stormhammer or by the more archaic spinfusil. Some tribes just call it the disc launcher.
The weapon fires a light, discus-shaped charge (the "spinfusor") wrapped in a transferro-covilium skin. The explosive is usually a magnetically activated, hypervolatile impact-oxidizer such as Gamma-T or ZJ-90. Once activated, the weapon creates a localized magnetic field that suspends the disk in the ready position and spins it up to a high speed. Without the magnetic field, the disk remains inert. However, with exposure to the spinfield, the ordinance gains its explosive potential, which is apparent in the "inflation" of the disk to a more discus-like shape, and by the flashes of electrical sparks that become visible within the disk itself.
When the trigger is pulled, a gravitic pulse accelerates the disk to subsonic velocity without disturbing the magnetic field of the disk. The disk's spin then provides a gyro-stabilizing effect such that the disk travels in a straight line to its target in all but the fiercest atmospheric conditions. In addition, the weapon creates a gravity "line" to further stabilize the disk's vector. This line persists for a moment or two only. Anyone who comes into contact with such a line would feel a slight wrench or push, not enough to deflect a man-sized mass, but perhaps enough to break a warrior's concentration. The gravitic "direction" imparted to the disk also forces it to travel at a constant speed. In flight, the transferro-covilium skin of the disk superheats and ablates, giving the ordinance its familiar light-blue trail. The disk alone is capable of beheading a warrior in light armor even if the explosive somehow malfunctions (a very rare event). The gravitic pulse also triggers the loading of the next disk from the magazine.
In the current model of the spinfusor, a very short delay occurs between the time of pulling the trigger and acceleration of the disk. Removal of the kinetic dampers eliminates this delay, but dramatically increases the risk of the magnetic field collapsing and detonating the weapon's entire payload. Consequently, warriors accept a lower rate of fire as an unalterable feature of this weapon.
Outside of the mortar, this weapon produces the greatest splash damage (over five meters' diameter) of all the traditional tribal weapons. Given the highly mobile nature of tribal warfare, this explosive damage effectively increases weapon accuracy, since even a near-miss can be sufficient to disable or kill a target. It should be noted that the explosion is thermal and concussive, but that the disk disintegrates completely without producing any shrapnel.
Standard ordinance for a spinfusor - one disk -- weighs about half a kilo. Lighter and heavier ammunition is available to achieve longer range or greater splash damage, but the standard loadout remains the most popular. A typical spinfusor magazine sits on top of the weapon and feeds the disk into the launch position, each disk is flat and takes up relatively little space until it has been magnetically charged. The gelid blue color remains dull until the disk enters the magnetic field, at which time the disk takes on its luminous blue, electrically-charged appearance. The weapon's greatest disadvantage is the low magazine capacity, since only fifteen disks can be carried at any one time.
I think the working title name needs to incorporate one of the following: The Spinfusor, The jetpack(jumpjets), and/or the epicness of the battles present in previous Tribes games. Each of those things is for the most part unique to Tribes games.