definitely a possibility, and its main guns do seem to fall in the Impaler family
I'm including it in the Diamondback. They fill the same role.
That being said, here's my
Hyper-Carrier Findings
Summary Report
Initial Analysis of Surviving Vehicle Bay Contents of CBB 4
Date: M43.*** ***
Author: Archmagos Tranth
I have completed the my initial sweep of the vehicle bays of Command Battleship 4 (Hyper-Carrier pattern), which has proven to be even more lucrative than predicted. In addition to the expected void craft, the ship apparently held a quite sizable ground troop compliment. While the vast majority of the bays were empty, the overall findings are several times that of the Well of Urd due to the ship's focus.
I start with the recognizable designs. In addition to a great many Jet Bikes, Land Speeders, and Land Raiders, there were several models that were immediately recognizable, at least to a senior member of the Mechanicus. Many of these were once part of the Imperium's arsenal during the Great Crusade, but were lost over the course of the Horus Heresy and the millennia of decay that followed. From a philosophical-moral standpoint, recovering these designs would be a large step forward for the Mechanicus.
Fellblade Super Heavy Tank: 12 Intact, 4 Partial.
The most immediately recognizable of the vehicles found. I have spotted several differences compared to the historical Tigrus pattern, and the exact performance characteristics have yet to be tested. None the less, this promises to be a superior option to the Baneblade for rebuilding the Trusts Super-Heavy force.
Fellsword Super Heavy Tank Destroyer: 5 Intact, 3 Partial.
I honestly have no idea what the difference between these and the Great Crusade era Falchion are, but I would like to find out. Again, this holds great promise for replacing the Trust's Shadowsword rosters.
Land Raider, Helheim pattern: 20 Intact
Apparently, the Land Raider was not held in particularly high regard among the Ancient's ground troops, at least as a main battle vehicle. While applauded for it's durability, it's poor fire arcs and relatively slow speed gave it a reputation as being an overly large moving target. It was simply too big and costly for it's roll.
Spartan Super Heavy Assault Vehicle: 20 Intact, 5 Partial
While not exactly an exact match, it is a close enough comparison. Much more highly regarded than it's smaller cousin, it was prized for it's ability to move more than twice the number of troops, along with being able to mount a much greater quantity of "toys". These "toys" were apparently tactical aids that did much to not only help the vehicle, but it's nearby friendly units as well.
Hunter AA Missile Vehicle: 20 Intact, 10 Partial.
Again, close enough for the designation to stick. These are certain to contain advanced fire control and guidance systems.
Predator Light Tank: 80 Intact, 30 Partial.
These samples appear to be offshoots of the Phobos pattern, with performance figures more in line with the Baal pattern. The vast majority of them are equipped in what are obviously combat drop configurations, likely to take advantage of the Predators relatively light weight to add support to initial landing efforts and increase possible deployment opportunities.
Storm Eagle Dropship: 60 Intact, 100 Partial.
Again, a close equivalence. These seem to have been the predominant infantry scale tactical transport of the Ancient's elite and semi-elite infantry formations.
Fire Raptor Gunship: 20 Intact, 10 Partial
No surprises here, the utility of this variant was no doubt obvious.
Now we go into the less recognizable designs. In many ways, we are quite fortunate here. One of the surviving data-terminals was loaded with documents detailing the design history of many of these finds. While not very helpful in terms of re-engineering them, these documents will do wonders in creating viable deployment doctrines.
"Tac" Fighter: 200 Intact, 600 Partial
The Ancients put much faith into unmanned vehicles, with this being the latest is a multi-century long chain. Equally long is the chain of insults and general disregard that the combat personnel had regarding its intelligence and projected service life. Ironically, it's low intelligence prevented the Men of Iron from compromising them in any large numbers. This type of strike craft was meant to be used as an attrition asset and formed the overwhelming bulk of the ship's void compliment. Cheap and having adequate performance, these fighters were used in massed swarms where individual capabilities were mostly irrelevant. It is armed solely with two Lascannon batteries in the front.
Griffon Fighter-Bomber: 100 Intact, 400 Partial
A companion unmanned craft to the Tac, the Griffon is a slightly larger design meant to provide missile based fire support. Equipped with no less than four missile pods, each comparable to those of the Xiphon Interceptor, the Griffon can a substantial amount of firepower downrange in a very short amount of time. Unfortunately, it's sole reliance on a missile based weapons suit limited it's endurance and made it quite vulnerable once it expended its compliment.
Banshee Tactical Strike Craft: 30 Intact, 10 Partial
While it may seem like a primitive throwback, there is more to this rotorcraft than meets the eye. The Banshee is actually a hybrid, with the rotors assisting a gravity-repulsion mechanism. The rotors were added as part of an effort to make a stealthy ground attack craft, capable of both surgical strike and area suppression missions. The majority of it's service history consists of counter-insurgency operations against less technically advanced foes, a roll in which it excelled well beyond expectation. Against the Men of Iron, it was regarded as little more than a moving target to any comprehensive AA grid, but perfectly functional once combat attrition had opened gaps to exploit. It has two missile pods mounted in the front.
Wraith Aerospace Supremacy Fighter: 20 Intact, 20 Partial
Considered to be one of the most advanced combat craft available to humans, the Wraith seems more like something the Eldar would create. The centerpiece of the design is a Holofield generator combined with a truly impressive EWAR suit, making it nearly impossible to hit while in flight. Rumors about the exact nature of the Holofield were countless, with the most common being that there is a Psychic component involved. It's acceleration demands a particularly advanced inertial compensator system to keep within human limits. It's weapons suit consists of two large hard points on the upper wings, while the lower wing houses a "Pulse" Lascannon capable of accurate and long ranged burst fire.
Hercules Dropship: 5 Intact, 10 Partial
This appears to be a militarized version of a more mundane cargo transport. The craft was (apparently) shockingly durable and had a large payload capacity for its size, which led this incarnation. The primary addition is an intriguing rapid deployment system, capable of landing it's compliment in seconds, and much more impressively, without the dropship ever touching the ground. Considering that it can carry a Warhound Scout Titan, this is something that bears further investigation.
Goliath Heavy Walker: 40 Intact, 20 Partial
The Goliath appears to be a somewhat dated holdover, being halfway between a Sentinel and Knight. It appears that the primary rationale behind retaining them was the relative cost and ease of use enabling made it a much more economic alternative to the later. The ability to field them in massed numbers also helped. It is said to be surprisingly capable against aircraft, likely due to the highly capable targeting system. It has two joint-less weapon arms, each with a missile battery and an Accelerator Cannon, the Impaler equivalent to the Autocannon.
Diamondback Medium Hover-Tank: 20 Intact, 20 Partial
This hover-tank was considered somewhat experimental, but was on the verge of being granted production clearance. Apparently, the Ancients had significant problems developing scalable gravity-repulsion craft, resulting a very wide and unfilled gap between the Land Speeder and the Hover Ship. It took them quite some time to develop a propulsion design that would be both economical and combat viable for anything larger than a Predator equivalent. Designs like the Banshee "cheated" via working around the various issues, but were never able to exploit the opportunities that a Grav-Craft could offer.
The Diamondback was one of the first designs that was considered to be truly viable. It is armed with a pair of turret mounted Fast Traverse Accelerator Cannons, closely matching the capabilities of the ancient Sicaran Battle Tank of the Astartes Legions. In comparison, the Diamondback lacks the sponson mounts of the Sicaran, but is much faster and agile. In addition, it is substantially smaller while remaining just as durable.
Garm Heavy Tank: 40 Intact, 40 Partial
I was apparently somewhat mistaken in my earlier analysis. The test models were apparently spread over several of the command ships. We may find more in the others.