The AL-X99 Airborne Labor (Alternatively, AL-X99 Prototype Helldiver) was an experimental prototype labor manufactured by Shinohara Heavy Industries (SHI). The type was the direct predecessor to the ARL-99 "Helldiver" military labor, and was designed to be deployed as a paratrooper. It appeared in the Patlabor: The Early Days OVA in Episode 6: "SV2's Longest Day (Part 2)".
Design & Development[]

AL-X99 Rear View

ARL-99 Helldiver (Production Model) rear view
The AL-X99 was the pre-production testbed for the ARL-99 Helldiver. While the types share a similar silhouette, they are very different looking machines, and it is evident that the Helldiver would undergo significant design alterations before being mass-produced. The machine, as its name suggests, was designed for airborne operations as a paratrooper-like unit, but could be deployed from a nuclear submarine's missile launch mechanism, if needed.
Armor[]
The armor system of the experimental model is entirely different from that of the production model. Every visible armor panel is different, and the angular plating akin to the AV-98 Ingram, which the type is based off of, would be phased out in exchange for more aerodynamic rounded panels. The type is entirely devoid of fabric coverings for the joints, as the SHI testing facility lacks much of the debris found in a real combat zone. The critical shoulder and hip joints of the prototype feature armor plating, which would be omitted on the production model to increase its range of motion. Noticeably missing are the Helldiver's signature leg-mounted airbrakes, which assist the pilot in making a controlled descent during airborne operations by slowing down the labor. In the case of the Airborne Labor, the structure of the legs below the knees seems to act as a shock absorber to soften the impact when landing. The type's modified backpack made room for additional sensors for test-run telemetry and diagnostics.
Controls and Electronic Equipment[]
Due to it's military spec it is equipped with an independent custom computer on the shoulder and an FCS (fire control system) consisting of a 64GB CD-RAM. While the AL-X99 was designed with a fully-enclosed armored cockpit, it was extensively modified for use by Hiromi Yamazaki. An exposed glass cabin, similar to those found on industrial vehicles, was fitted in addition to the removal of all non-critical systems to allow the officer to fit inside. This canopy was used during early tests of the labor, and allowed the pilot to have a great degree of visibility, likely to make it easier to land the machine. The prototype also mounts a six-tube smoke discharger on either shoulder, a feature noticeably missing from the production model. However, the AL-X99 mounts no offensive weaponry, lacking the Helldiver's signature arm-mounted 40mm machine gun. It can be assumed that, because the type is a complete prototype, the AL-X99's internal drive mechanisms and sensor equipment are similar, if not identical to those found on the Helldiver.
Operational History[]
The AL-X99's full operational history is unclear, as in-universe it is likely classified information. The type was rolled out in 1998 or 1999, and would be borrowed by the Tokyo Metropolitan Police Department Special Vehicles Unit, Section 2, to participate in the effort to end the military occupation of Tokyo by rebellious members of the Japan Self-Defense Forces. When these forces seized ocean ferries and mounted nuclear missile launchers, Hiromi Yamazaki boarded the AL-X99 aboard a submarine, and launched directly onto the bow deck of one of the ferries, taking fire from the various weapons of the military members on board, but destroying the missile launcher with a single hand. Following this operation, the heavily damaged AL-X99 would be returned to SHI, where its further use, if any, is unknown.
Specifications[]
Empty Weight: 5.27 tons
Maximum Operating Weight: 6.04tons
Minimum Revolving Radius: 3.90 meters
Armor Material: Carbon Reinforced Material; Carbon Fiber Reinforced Plastics
Armaments[]
- 6-count Smoke Discharges x2