I have long thought turbolaser bolts could be best described as projectiles sheathed in some manner of brightly visible energy or some material. The reason I prefer this generalized description is that it avoids pseudo magical particles required when describing turbolaser bolts as energy weapons and it neatly provides a method by which both variable turbolaser bolt velocitys and exploding turbolaser bolts may be allowed.
As I understand the evidence turbolaser bolt behavior can be summarized thusly:
- [1] Bolts are visible to the eye and come in shades of red, green and blue. Possibly violet if Geonosian fighter weapons count.
[2] Bolts assume varied shapes. Some are unremarkable rounded rectangles in cross section, many have points on the leading end and taper toward the trailing end. Some also have bulges along their length.
[3] Bolts of all calibers possess wildly varying propagation speeds. In general any given bolt will take 3 to 4 frames to travel to a given target, with no regard given to the distance.
[4] Some bolts have been observed tracking targets, or moving laterally, in a way directly comparable to sweeping a beam.
[5] Upon impact with defensive shielding some bolts will seem to fragment or splinter into many glowing shards which further break apart and disappear with a flash.
[6] Many bolts have been observed exploding around intended targets, not usually with tremendous effect.
[7] A few turbolaser bolts have been observed damaging unshielded asteroids just prior to visibly coming in contact.
Working with the turbolaser bolt as a projectile idea I propose the following:
A physical shell exists which carries the mechanics required to generate a powerful energy field. This energy field (probably) shares characteristics with defensive shields and is the chief method by which the shell penetrates defensive shielding and causes damage. Energy, and thus damage potential, is stored within the shell and expressed through the energy field.
Depending on the shell additional mechanics may exist, such as a means to alter the shell's trajectory and to sense a guide by which the shell is steered.
Due to the (assumed) nature of defensive shielding unprotected physical contact with an outer defensive layer ('ray' shields) results in rapid melting or vaporization of any relatively small object. Energy imparted by this shielding layer is a function of time. A second (assumed) layer of defensive shielding ('particle' or deflector shields) serves to physically repel resulting gases, liquids and residual fragments. Contact time has no effect on energy imparted by this shield layer, it applies a force over its distance and can retard a certain maximum amount of kinetic energy.
This assumed shielding system requires all projectiles either possess great speed or great shielding of their own to survive the outer layer. Observe small asteroids with low velocity relative to the Millennium Falcon vaporize on contact with the shielding. The energy required to flash vaporize such an object is greater than the kinetic energy observed (as I recall it) and is provided by the shielding system. Observe also that many known missile systems employ visible energy fields and are sometimes indistinguishable from turbolaser, laser bolts.
To deal with the outer shielding layer either go fast, go shielded or go both. Observe that slow and shielded is preferred. Bolts take 3 to 4 frames to reach any given target at any given range. This means bolts are fired slow when the operators can get away with it. If greater velocities were favored bolts would always propagate fast.
The reason has to do with the inner shield layer. The shell generates a visible energy field which protects itself from the outer shield layer, and which also aids penetration of the inner shield layer. The method by which the shell's energy field penetrates this shield layer depends on the relative strengths of the energy field and the shield, and also on contact time. A longer contact time results in a greater penetration of the shield layer and for this reason slower shell velocities are preferred. Penetrating the second shield layer in this manner is less energy costly than a brute force method and gives such an equipped shell an advantage over a purely kinetic projectile.
(It should be noted that it may be necessary to assume the shell may focus on generating one energy field or another at any given time but not both. Normally the shell focuses on protecting itself from the outer shield layer first then switches to focus on defeating the inner layer. This assumption is used to allow bolt fragmentation. Possibly bulges sometimes found along bolt lengths allow several energy field types to be generated, which gives the shell an advantage penetrating a fully angled shield.)
To defeat the second defensive shield layer either go fast or go slow and shielded. The advantage is in the second option; cracking the shield with brute kinetic energy is possible but only the remainder energy will affect the hull. Successfully disabling and so penetrating the shield allows a far greater energy remainder to affect the hull. Observe that at close ranges slow bolt speeds are observed which suggests these speeds are preferred.
To wrap this up notice that at large ranges a greater shell velocity is required if the target is capable of actively defending. A balance then is needed between scoring hits and firing potentially damaging hits. Too slow and the opponent, if maneuverable, will avoid it or, if not maneuverable, will angle shields unpredictably and cause the shell to fragment, wasting most of its energy. It is likely convention then to set the shell velocity so that there is a 1/6 second lag between firing and striking.
Some smaller things:
- Variations in turbolaser bolt geometry have to do with the energy field's configuration and may be intended to better penetrate stacked shields or shields which are angled a certain way at the time of firing.
- Turbolaser bolt colors can be considered part of the nature of the energy field generators. Presumably a wide range of EM frequencies are possible, but visible colors are preferred for use as tracers in ECM heavy battle environments. (I prefer to consider a shell's energy fields to be largely similar to defensive shielding fields, only with a visible emission accounting for their visibility and a non visible emission frequency accounting for the invisibility of shields)
- Maneuvering engines and rear facing sensors allow some shell models to following a pointing beam (most likely a real laser) and be made to track a moving target in an environment with too much ECM to allow on board tracking sensors, or transmitted instructions much success.
- Internal energy capacitors may explode, either intentionally or not, resulting in observed flak shots. Sudden vaporization of the shell results in a lack of debris and the explosion is tinted by the hue of its residual energy field.
- Turbolaser bolt fragmentation or splintering may result when a shell is damaged. The second defensive shield layer, (most likely) the deflector shields, may be angled according to dialog. Perhaps this may mean a layer of (physically) deflecting shield may be focused outside the normal shielding system and in the path of the bolt. If the shell is set to defend against the outer ('ray') shield and its thermal effects before focusing on defeating the physical (deflector, or 'particle') shield it may be ill equipped and the shell suffers sudden deceleration and damage passing through the angled deflector shield. The shell fragments and the energy field only remains visible because it too has mass and does not wink out of existence immediately. The poorly or unshielded fragments pass into the outer shield layer and are vaporized.
- If shields may be invisible, then perhaps a shell may generate part or all of its damaging energy field invisibly.
To conclude, I think an energy field wrapped shell can explain all turbolaser behavior I am aware of in the movies. I also believe it is more satisfactory than the energy beam explanation, although I did not go into why.
I do hope this wasn't too long or dry