The 'Allegiance' Star Destroyer

[Vympel]

Hey guys, this thread is for speculation as to the capabilities of the Star Destroyer that features prominently in the Dark Empire comics, provisionallyknown by the name of one of its class, Allegiance.

However, since Allegiance is not a Kuat Drive Yards class name- other notables being

Acclamator
Imperator
Mandator (SW2ICS)
Procurator (SW2ICS)
Executor

I propose that a more appropriate class name would be one of the following

Praetor
Censor
Dictator

Note that any other suggestions preferably are Latin (as in Roman Empire), and even better end in "or".

Now then

Saxton on the 'Allegiance' type: http://www.theforce.net/swtc/dagger.html#allegiance

"These destroyers are ubiquitous in situations involving a heavy fleet presence. They operated in an escort formation with the Eclipse, and participated in the enforcement of the security cordon around the planet Byss. Allegiance, the largest destroyer present at the Battle of Calamari, shares all of the distinctive structural features of this class and is the same size, approximately 2.2km long. For this reason, I provisionally refer to all of these ships as the Allegiance-class star destroyer. (I will replace this label whenever the official KDY classification becomes known.)

The warship is similar in form to the common Imperator-class star destroyer, but with several subtle but crucial distinctions. The stern, thrusters and command module are almost identical to those of the smaller vessel, but the main hull is significantly longer and more sharply pointed. The features surrounding the command tower are smoother than the terraced forms on the dorsal surface of an Imperator, with greater coverage by the flat armour plates and less exposure of inter-plate cortical surfaces. The ventral bulb of this ship is approximately ten times the volume of that on the Imperator. (According to the common assumption that the bulb surrounds part of the power or propulsion systems of a ship, the Allegiance design probably has much superior thrust, firepower and shieldpower.)

Unlike the smaller destroyers, there is a complete lack of any docking bay suitable for accommodating large starships. Any TIE or shuttle hangars must be small and open directly to space. This implies an important functional distinction: the destroyer's design is oriented away from the carrier or mothership role. This seems to be a compromise for reducing points of vulnerability and installing more extensive hull plating. The Allegiance design assumes and is dedicated to large fleet engagements, operating in concert with complimentary warship designs. For starfighter screening in combat, it must depend on the squadrons launched from other vessels such as the huge dedicated carrier ship seen in the fleet of Admiral Giel. In contrast, the Imperator is necessarily less specialised since it is often deployed on patrol in remote regions where it sometimes is the largest ship available."


So, let's hear some estimates for weapons and shields from the knowledgeable forum denizens!

[Spartan]

Okay here are some assumptions:

Power Output

Dr. Saxton credits the Allegiance class with a reactor volume approximately 10x that of a common Imperator Star Destroyer. He also credits the ISD with a reactor output of 1E25W. So the Allegiance should have a power output of 1E26; assuming that its reactor's power density is not higher than an ISD.

Shield Output

Ten times the power of an ISD... If we assume that shield capacity is 1/4 power output (despite, the problems with doing so), that's 2.5E25W (5,952 TT).

Sublight Acceleration

Now look at these images:
http://www.theforce.net/swtc/Pix/comics/de/eclipse3.jpg
and Darth Wongs ISD pics at
http://www.stardestroyer.net/Empire/index.html

The Ion engines appear to be about the same size, at the very least the Allegiance's engines haven't been scaled to the vessels size. Its possible that the engines make up for this with a higher output. But I'd hazard a guess that it is probably slower at sublight than an ISD.

Weapons Systems

The Allegiance undoubtedly is more heavily armed than an ISD. The shots in DE don't clearly show the most of the weapons. However, when the Starlight Intruder flies through the defense fleet at Byss; we see the Allegiance class has numerous heavy twin mounted turbolaser in the brim trench.

Starfighters Complement

The Allegiance class does mount a single forward hangar, I'll scale it from DE when I get home. The hangar is shown open on the vessel destroyed at Nar Shadda. In other shots notably the ones depicting combat there is a rectangular hull plate where the hanger appears. So the hangar has a heavy blast door that closes for battle. Just because the hangar aperture is reduced in size compared to an ISD. We should remember that the Allegiance has far greater internal volume, and even a Nebulon-B frigate carries a squadron of starfighters. Now an Allegiance won't be landing any AT-AT's, but se could easily carry many more starfighters than an ISD.

There may also be launch bays concealed in the brim trenches, similar to the Eclipses side mounted launch bays.
[/img]

[AL]

Okay here are some assumptions:

Power Output

Dr. Saxton credits the Allegiance class with a reactor volume approximately 10x that of a common Imperator Star Destroyer. He also credits the ISD with a reactor output of 1E25W. So the Allegiance should have a power output of 1E26; assuming that its reactor's power density is not higher than an ISD.

Shield Output

Ten times the power of an ISD... If we assume that shield capacity is 1/4 power output (despite, the problems with doing so), that's 2.5E25W (5,952 TT).

Sublight Acceleration

Now look at these images:
http://www.theforce.net/swtc/Pix/comics/de/eclipse3.jpg
and Darth Wongs ISD pics at
http://www.stardestroyer.net/Empire/index.html

The Ion engines appear to be about the same size, at the very least the Allegiance's engines haven't been scaled to the vessels size. Its possible that the engines make up for this with a higher output. But I'd hazard a guess that it is probably slower at sublight than an ISD.

Weapons Systems

The Allegiance undoubtedly is more heavily armed than an ISD. The shots in DE don't clearly show the most of the weapons. However, when the Starlight Intruder flies through the defense fleet at Byss; we see the Allegiance class has numerous heavy twin mounted turbolaser in the brim trench.

Starfighters Complement

The Allegiance class does mount a single forward hangar, I'll scale it from DE when I get home. The hangar is shown open on the vessel destroyed at Nar Shadda. In other shots notably the ones depicting combat there is a rectangular hull plate where the hanger appears. So the hangar has a heavy blast door that closes for battle. Just because the hangar aperture is reduced in size compared to an ISD. We should remember that the Allegiance has far greater internal volume, and even a Nebulon-B frigate carries a squadron of starfighters. Now an Allegiance won't be landing any AT-AT's, but se could easily carry many more starfighters than an ISD.

There may also be launch bays concealed in the brim trenches, similar to the Eclipses side mounted launch bays.
[/img]

The only thing i question is the Nebulon B thing. It does not appear to be large enough to support fighter craft. http://www.theforce.net/swtc/misc.html#continuity

the Allegiance may not support fighter craft at all but may have a bay for shuttles and supply ships only. It is very hard to say.

[Executor]

Okay here are some assumptions:

Power Output

Dr. Saxton credits the Allegiance class with a reactor volume approximately 10x that of a common Imperator Star Destroyer. He also credits the ISD with a reactor output of 1E25W. So the Allegiance should have a power output of 1E26; assuming that its reactor's power density is not higher than an ISD.

Shield Output

Ten times the power of an ISD... If we assume that shield capacity is 1/4 power output (despite, the problems with doing so), that's 2.5E25W (5,952 TT).

Sublight Acceleration

Now look at these images:
http://www.theforce.net/swtc/Pix/comics/de/eclipse3.jpg
and Darth Wongs ISD pics at
http://www.stardestroyer.net/Empire/index.html

The Ion engines appear to be about the same size, at the very least the Allegiance's engines haven't been scaled to the vessels size. Its possible that the engines make up for this with a higher output. But I'd hazard a guess that it is probably slower at sublight than an ISD.

Weapons Systems

The Allegiance undoubtedly is more heavily armed than an ISD. The shots in DE don't clearly show the most of the weapons. However, when the Starlight Intruder flies through the defense fleet at Byss; we see the Allegiance class has numerous heavy twin mounted turbolaser in the brim trench.

Starfighters Complement

The Allegiance class does mount a single forward hangar, I'll scale it from DE when I get home. The hangar is shown open on the vessel destroyed at Nar Shadda. In other shots notably the ones depicting combat there is a rectangular hull plate where the hanger appears. So the hangar has a heavy blast door that closes for battle. Just because the hangar aperture is reduced in size compared to an ISD. We should remember that the Allegiance has far greater internal volume, and even a Nebulon-B frigate carries a squadron of starfighters. Now an Allegiance won't be landing any AT-AT's, but se could easily carry many more starfighters than an ISD.

There may also be launch bays concealed in the brim trenches, similar to the Eclipses side mounted launch bays.
[/img]

If that Star Destroyer that was destroyed at Nar Shadda is an Allegiance (it does seem overall more massive and a sleeker dagger shape, so it probabley is) some of the pictures show it having the same arrangement as the Imperators, a bigger hanger towards the middle and a smaller one forward of that. Also the other pics you mentioned with the guns in the trench show the destroyer in the background having 2 hangers, I pursume this is the hip seen on the previous page, which does seem very likely to be an Allegiance due to the size of the reactot dome.

I have always pursumed that all imperial ships carry fighters and troops, since all stats given for ships from strike cruiser up seem to be able to carry at least a squadron of fighters and maybe an AT-At or similar land vehicle. I think all they all will have massive blast doors that can cover the hangers, I've seen a fan made computer art with these on an Imperator, and it does make sense, I always thought the ISD in ROTJ that didnt show a hanger bay was one with the doors closed.

[AL]

Okay here are some assumptions:

Power Output

Dr. Saxton credits the Allegiance class with a reactor volume approximately 10x that of a common Imperator Star Destroyer. He also credits the ISD with a reactor output of 1E25W. So the Allegiance should have a power output of 1E26; assuming that its reactor's power density is not higher than an ISD.

Shield Output

Ten times the power of an ISD... If we assume that shield capacity is 1/4 power output (despite, the problems with doing so), that's 2.5E25W (5,952 TT).

Sublight Acceleration

Now look at these images:
http://www.theforce.net/swtc/Pix/comics/de/eclipse3.jpg
and Darth Wongs ISD pics at
http://www.stardestroyer.net/Empire/index.html

The Ion engines appear to be about the same size, at the very least the Allegiance's engines haven't been scaled to the vessels size. Its possible that the engines make up for this with a higher output. But I'd hazard a guess that it is probably slower at sublight than an ISD.

Weapons Systems

The Allegiance undoubtedly is more heavily armed than an ISD. The shots in DE don't clearly show the most of the weapons. However, when the Starlight Intruder flies through the defense fleet at Byss; we see the Allegiance class has numerous heavy twin mounted turbolaser in the brim trench.

Starfighters Complement

The Allegiance class does mount a single forward hangar, I'll scale it from DE when I get home. The hangar is shown open on the vessel destroyed at Nar Shadda. In other shots notably the ones depicting combat there is a rectangular hull plate where the hanger appears. So the hangar has a heavy blast door that closes for battle. Just because the hangar aperture is reduced in size compared to an ISD. We should remember that the Allegiance has far greater internal volume, and even a Nebulon-B frigate carries a squadron of starfighters. Now an Allegiance won't be landing any AT-AT's, but se could easily carry many more starfighters than an ISD.

There may also be launch bays concealed in the brim trenches, similar to the Eclipses side mounted launch bays.
[/img]

If that Star Destroyer that was destroyed at Nar Shadda is an Allegiance (it does seem overall more massive and a sleeker dagger shape, so it probabley is) some of the pictures show it having the same arrangement as the Imperators, a bigger hanger towards the middle and a smaller one forward of that. Also the other pics you mentioned with the guns in the trench show the destroyer in the background having 2 hangers, I pursume this is the hip seen on the previous page, which does seem very likely to be an Allegiance due to the size of the reactot dome.

I have always pursumed that all imperial ships carry fighters and troops, since all stats given for ships from strike cruiser up seem to be able to carry at least a squadron of fighters and maybe an AT-At or similar land vehicle. I think all they all will have massive blast doors that can cover the hangers, I've seen a fan made computer art with these on an Imperator, and it does make sense, I always thought the ISD in ROTJ that didnt show a hanger bay was one with the doors closed.

when i was a kid i used to have the die cast metal isd and it had a sliding blast door to cover the massive hangar bay and i have also seen the fan made computer image of this door and it makes great sense

[Executor]

when i was a kid i used to have the die cast metal isd and it had a sliding blast door to cover the massive hangar bay and i have also seen the fan made computer image of this door and it makes great sense

Theres a link to the site on Curtis's website under the Star Wars Links

[Spartan]

AL wrought:

The only thing i question is the Nebulon B thing. It does not appear to be large enough to support fighter craft. http://www.theforce.net/swtc/misc.html#continuity

the Allegiance may not support fighter craft at all but may have a bay for shuttles and supply ships only. It is very hard to say.

I agree that the Neb-B doesn't appear to have any space for a fighter complement. But the official material, says it does. Who knows perhaps they gutted some of the interior spaces and camaflaged the hangar bay door. It makes since if the Rebel Neb's have a chop-shop modifications, that stock Neb's don't have. Then the fighters are easily explained because they could easily sacrificed cargo space, and crew berthing to fit in a small hangar. Plus with tractor beams they don't need much deck space to launch. An Imperial Star Frigate running up against a Rebel Neb-B, wuold get a nasty surprise if, they don't normally carry fighters. But hey did you see the Correlian corvette in the other thread, even it has fighter!

Now the Allegiance class almost certainly has some kind of fighter craft. The reason being that even a vessel immune to enemy fighter can beneifit from having them. For example fighters force an enemy vessel to use full shields; instead of shielding only the direction its taking capital ship fire from. Fighters are useful for scouting, patrolling, and as an alternate sensor platform, in the event that the parent vessel encounters heavy jamming.

[Master of Ossus]

Incidentally, the Nebulon-B doubtless carries many of its fighters in external racks, as shown by the MF in ESB. It probably does service some fighters and light freighters, but many of those can be external, reducing the problems created by internal space on a ship that size.

[Vympel]

Excellent post Spartan!!!

The one thing is the brim trench guns shown in Dark Empire- these were taken directly from a concept drawing of Star Destroyer weapons that wasn't used in ROTJ:

"Star Destroyer Waist Band Gun"
&
"Star Destroyer Guns"

These are probably the small/medium guns that are near invisible against a Star Destroyer's massive bulk- rather than heavy weapons. But they still look cool. Got anywhere I can find a picture of how they look in Dark Empire? (Got the impression it was the same as the ROTJ concept art)

[Spartan]

Okay I just checked DE their are indeed (2) hangar bays on the Allegiance class. Both hangars have very prominent blast doors, in most shots only the smaller forward bay is open. However, when the un-named Allegiance's tractors the control spire over Nar Shadda the main bay is open. Looking closely at the roof of the bay, there are what appears to be a railing system. It looks similar to what ISD's use to dock their tie fighters.

I measured the hangar bays and got 132 meter for the larger bay, and 88 meters for the smaller (foremost) bay. So the main bay could still easily swallow a 120 meter Corellian corvette.

I also checked the Byss security cordon scenes again. There are twin mounted turbolaser turrets on the upper and lower lips of the brim trenches. The sequence appears to alternate; up-down-up. The turrets are 1/4 the height of the trench; and measuring the distance between turrets, they are two turret width’s apart. The setup is similar to the Acclamator’s brim guns. However, since they are twin mounts instead of twin mounts instead of quads, they must be far larger given the difference in brim trench sizes between the two classes.

Hey! I just found another shot from that scene that shows single gun turrets mounted in the brim trench, that are even larger than the Twin turrets. The turrets height of the brim trench, the single gun is mounted off center with what appears to be a large sensor, in a rounded turret. The spacing between these is only one turret width. These weapon may be ion cannons since they look distinctly different than other brim turrets.

Clearly if these weapons densities hold for the entire 2.2 km length of the trench the number of weapons are in the hundreds.

I'm going to try and scale the trench to the size of the vessel; then the turrets to the trench, and finally the barrel diameters to the turrets. I'll post them tomorrow.

[Spartan]

Master of Ossus wrote:

Incidentally, the Nebulon-B doubtless carries many of its fighters in external racks, as shown by the MF in ESB. It probably does service some fighters and light freighters, but many of those can be external, reducing the problems created by internal space on a ship that size.

You make an excellent point about external racks. In fact in DE2 we again see the Flacon docked at the side of Brand's Ganthan Battlship. it appears that to docking arms extend from the vessel an hold the Falcon between them like a C-clamp (the actual docking clamp in even offset correctly in he picture, to match the MF top hatch from TESB).

[Spartan]

Vympel wrote:

Excellent post Spartan!!!

Thanks!

These are probably the small/medium guns that are near invisible against a Star Destroyer's massive bulk- rather than heavy weapons. But they still look cool. Got anywhere I can find a picture of how they look in Dark Empire? (Got the impression it was the same as the ROTJ concept art)

As you probaly saw in my post before this one, the Alliegances brim guns are very similar to the ones you posted; but compared to the size of the trench they are not point defense weapons. More to follow on those barrel sizes. Also there are those large single barrel turrets, the ion cannons on ISD's are single mounts I believe. So that would be my guess, that really big turbolasers

[Vympel]

Eagerly awaiting barrel size estimates- I'm a big fan of the Allegiance

[phongn]

A possible second explanation for the Nebulon-B's fighter complement is based off of an EFX glitch in ROTJ, creating a much larger ship that should be capable of having starfighters.

[Spartan]

Okay, here is my scaling of the Allegiance class Star Destroyers trench mounted turrets and gun barrels. Please note that I have found three distinctively different turret type:

The height of the brim trench varies between 32-36 meters. My scaling is based on the trench average height of 34.3 meters.


Twin turret type 1:

Turret height: 9.3 m
Turret diameter at base: 12.4 m
Barrel diameter: 1.55 m
Barrel length: could not be determine due to viewing angle.

This turret type has a rounded dome-like shape. The spacing for this type is two turret width’s apart. With four turrets mounted with in a 54 meter length of the trench. There are twin mounted turbolaser turrets on the upper and lower lips of the brim trenches.

Twin turret type 2:

Turret height: 9.3 m
Turret width: 14.88 m
Barrel diameter: 0.78 m
Barrel length: could not be determine due to viewing angle.

This turret type is a shallow dome shape. The spacing for this type is the same as the type 1, and it appear that the to turret types alternate.

Single turret:

Turret height: 18.2 m
Turret width: 26.0 m
Barrel diameter: 2.1 m
Barrel length: could not be determine due to viewing angle

These are single gun turrets mounted in the brim trench on the upper and lower lip; that are even larger guns than the twin turrets. The single gun is mounted off center with what appears to be a large sensor, in a rounded turret. The spacing between these is only one turret width. These weapon may be ion cannons since they look distinctly different than other brim turrets.

Compare this to the barrel diameters on an ISD2's HTL's which are around 1.2-1.3m.

[Vympel]

Excellent. Allegiance clearly has a lot of firepower in its waist. If only we could get a good look at its dorsal and ventral surfaces ...

[nightmare]

Just a note. I've scaled the actual Allegiance picture as witnessed in the battle of Mon Calamari to almost exactly 2800 m length, not 2200 m. This is assuming that the ship in the foreground is a standard ISD or ISD-II class.

[Spartan]

nightmare wrote:

Just a note. I've scaled the actual Allegiance picture as witnessed in the battle of Mon Calamari to almost exactly 2800 m length, not 2200 m. This is assuming that the ship in the foreground is a standard ISD or ISD-II class.

Those are not ISD's, the vessels are not even KDY brand. The vessels by my scaling and SW technical Comentaris is appox. 900 meter. So they are the same size as a Victory star destroyer, but more heavily armored. They also do not have the additional "air foils" that VSD mount. So they are light destroyers, assumably designed to serve only as combat escorts (ie. no visible hangar bays).

[Spartan]

Hey, Vympel

I've got a slow period coming up at work, so I'm going to make the Allegiance my next CG modeling project. When I get some pitures or animations done I'll see that you get them. I'm hoping to have it done by months end, and I'll post a link to any WIP's as I get them done.

[Vympel]

*jumping up and down with glee*

[Executor]

nightmare wrote:

Just a note. I've scaled the actual Allegiance picture as witnessed in the battle of Mon Calamari to almost exactly 2800 m length, not 2200 m. This is assuming that the ship in the foreground is a standard ISD or ISD-II class.

Those are not ISD's, the vessels are not even KDY brand. The vessels by my scaling and SW technical Comentaris is appox. 900 meter. So they are the same size as a Victory star destroyer, but more heavily armored. They also do not have the additional "air foils" that VSD mount. So they are light destroyers, assumably designed to serve only as combat escorts (ie. no visible hangar bays).

They are a KDY Destroyer they have similar bridge tower and domes, Curtis also has them scaled to 1200 metres.

[nightmare]

nightmare wrote:

Just a note. I've scaled the actual Allegiance picture as witnessed in the battle of Mon Calamari to almost exactly 2800 m length, not 2200 m. This is assuming that the ship in the foreground is a standard ISD or ISD-II class.

Those are not ISD's, the vessels are not even KDY brand. The vessels by my scaling and SW technical Comentaris is appox. 900 meter. So they are the same size as a Victory star destroyer, but more heavily armored. They also do not have the additional "air foils" that VSD mount. So they are light destroyers, assumably designed to serve only as combat escorts (ie. no visible hangar bays).

They are most definitely KDY brand. I see no reason why they should be light destroyers, particularly as the Allegiance is nicknamed "super", which means it has to be larger than standard. If those are VSD size, this can't be. Maybe I should include the pic to make sure what I'm talking about.

[nightmare]

Btw, I drew out the nose of the foreground destroyer and compared the keels to get my scaling. I think Saxton came to a smaller number because he considers several other pictures ASDs as well, even though this is THE Allegiance. The other pics leave more to the imagination, I think this is the best possible picture, maybe even the only one, to get any accurate scaling of the ASD.

[Executor]

Btw, I drew out the nose of the foreground destroyer and compared the keels to get my scaling. I think Saxton came to a smaller number because he considers several other pictures ASDs as well, even though this is THE Allegiance. The other pics leave more to the imagination, I think this is the best possible picture, maybe even the only one, to get any accurate scaling of the ASD.

I have the allegiance at around 2600 meters, but I cant remember where i got that length from

[Spartan]

nightmare wrote:

They are most definitely KDY brand. I see no reason why they should be light destroyers, particularly as the Allegiance is nicknamed "super", which means it has to be larger than standard. If those are VSD size, this can't be. Maybe I should include the pic to make sure what I'm talking about.

Nice Pic!

But...um how can you tell there KDY towers from fireballs? Kidding... We have been talking about different pictures sorry for the confusion, I was thinking of the Destroyers escorting Sedriss's ASD at the Battle of Balmora. Sorry

Btw, I drew out the nose of the foreground destroyer and compared the keels to get my scaling. I think Saxton came to a smaller number because he considers several other pictures ASD’s as well, even though this is THE Allegiance. The other pics leave more to the imagination, I think this is the best possible picture, maybe even the only one, to get any accurate scaling of the ASD.

I believe you have over estimated the size. Dr. Saxton measured all the relevant pictures and took the average length. Besides those other ships you mention are not similar they are identical, in general hull shape and profile. We are dealing with line drawings so we can hardly expect them to be completely consistent. I seriously doubt the artist bothered to scale each comic panel to insure the ASD or any other vessel was accurately portrayed. But, hey what's + or - 400 meters among friends. All our estimates are speculation, and are therefore suspect. However, I'll make a small appeal to authority here. Dr. Saxton did write ICS, and is a sure thing for Episode III ICS. If he says their 2.2 km long that's good enough for me. Hopefully when some Lucasfilm employee hits on the bright Idea of making a Jane's Fighting Starships of the Galactic Empire (and it companion volumes ) they'll have the good sense to call him.

I called them light destroyers and even at the correct 1200 meter, they are compared to the Allegiance. Also it fits RL, where most destroyers and cruisers were broken down into: light, standard, and heavy classes.

Now if we consider they ASD as a light cruiser, then those ships are just plain-jane destroyers. Then again there are those 750 m long Cantwell class star destroyers, so one never knows.