Artillery's an easy life, they said...

Defense of Yokohama Base
BETA Assault on Yokohama Base
Timeframe December 29, 2001
Location(s) involved Yokohama Base, Japan
Outcome United Nations/Empire of Japan pyhrric victory.
Known Belligerents
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United Nations

UN 11th Force

Special Task Force A-01
1st Tactical Armored Battalion
2nd Tactical Armored Battalion
3rd Tactical Armored Battalion
4th Tactical Armored Battalion
5th Tactical Armored Battalion
6th Tactical Armored Battalion
7th Tactical Armored Battalion
101st Mechanized Infantry Regiment
108th Mechanized Infantry Regiment
116th Mechanized Infantry Regiment
1st Air Support Unit
2nd Air Support Unit
3rd Air Support Unit
4th Air Support Unit
5th Air Support Unit
6th Air Support Unit
7th Air Support Unit
105th Air Support Team
Artillery units (M2001 Crusader)
Artillery units (MLRS)
Main Battle Tank units (Leopard 2A7I)

Empire of Japan
Imperial Japanese Army/Mainland Defence Force

Artillery Units
Several TSF Regiments

Imperial Japanese Royal Guard

19th Independent Guard Flight

Imperial Japanese Navy

2nd Squadron
8th Squadron
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Sadogashima Hive (H21)

Brigadier-General Paul Radhabinod (UN)

Professor Kouzuki Yuuko (UN)

Lieutenant Tsukuyomi Mana (IJ-IRG)
- - -

Heavy casualties to base personnel, moderate damage to Yokohama Base.

Heavy casualties, numbers reduced to less than 10,000.

The Defence of Yokohama Base took place on December 29, 2001, when a large group of 30,000 to 40,000 BETA initiated an assult on Yokohama Base of the UN 11th Force at night; the BETA were stragglers from the previous Sadogashima Hive Battle and were seeking out the Yokohama Hive's reactor in order to replenish their energy. Professor Kouzuki Yuuko's assumed that the remaining BETA within the Sadogashima Hive's various stabs would attempt to make for the Cheorwon Hive or another continental Hive; those assumptions proved erronous.

During their assault, the BETA demonstrated noticable use of tactics in this battle, using diversions to bypass UN defence lines laid in front of the base with impunity to strike at weak points. They reached as far as the deepest levels of Yokohama Base, where the Yokohama Reactor was located, and their forces were spread throughouly throughout the base and engaged with all human defences; all 250 TSFs, armored units, air support, and even mechanized and security infantry.

Yokohama's forces, led by Brigadier General Paul Radhabinod and Professor Kouzuki Yuuko as both the commander of A-01 and in an advisory role for Colonel Radhabinod, comprised of Special Task Force A-01, the 1st to 7th Tactical Armored Battalions, the 101st, 108th, and 116th Mechanized Infantry Regiments, 1st to 7th Air Support Units as well as their own MLRS, MBT, and artillery units.

They were supplemented by local Imperial Army/Mainland Defence Force artillery units and the 19th Independent Guard Flight led by Lieutenant Tsukuyomi Mana of the Royal Guard. Other units were the Imperial Navy ships of the 1st Squadron: Owari, Kii, and Izumo provided naval gunfire support from Tokyo Bay. Actual reinforcements, however, were not available from either the Empire of Japan, US Army forces, or even the surrounding UN bases.


Due to the damage caused to the Empire of Japan's Secondary Defence Line on the eastern shores by the XG-70b's explosion during Operation 21st, and increased volcanic activity in the region, the traveling horde was not detected any earlier. Burrowing from deep underground beyond the range of temporarily-set-up sensors, the BETA were only detected by the Takazaki and Chichibu observational posts, with a projected emergence area at Old Machida Town within roughly 70 minutes.

The Imperial Army and Mainland Defence Force were unable to spare any significant forces to reinforce Yokohama Base, with most of the entire Imperial Army concentrated around Kyoto in its defence. The other UN bases also lacked manpower, and US Army assets could not be called on within the timeframe of the attack. In order to repel the assault, the UN set up their artillery to aim for the wave behind the charging Destroyer-class that the BETA vanguard was composed of; the TSF battalions were arranged in a three-layered line formation to intercept those that would escape the bombardment, with the 1st and 2nd Tactical Armored Battalions placed on the New Yokohama Road as the Primary Defence Line, followed by the 3rd and 4th Battalions and 5th and 6th Battalions as the Secondary and Tertiary Defence Lines in a semicircle formation around the base. STF A-01 was deployed along with two flights of TSFs from the 7th Battalion and the 19th Independent Guard Flight around Yokohama Base's No. 2 Runway, where the XG-70d's hangar lift access was.

The planned bombardment began earlier than planned, but that was due to the BETA's appearance. However, the BETA at Machida were a diversion; the main force used the vibrations of the artillery firing in order to mask their movement underground. The BETA immediately engaged UN forces once aboveground at the Secondary Defence Line, with the F-15s of Victor Unit bearing the brunt of the intitial attack. The BETA quickly broke through the Secondary Defence Line and engaged forces at the Third, forcing Brigadier-General Paul Radhabinod to scramble the 105th Air Support Team to reinforce them. The 1st and 2nd Battalions, which were still at full strength, were quickly recalled to the base, and the 3rd and 4th Battalions were ordered to retreat and regroup at the Tertiary Defence Line to clear away from the new artillery bombardment zones, which now included the Primary and Secondary Defence Line.

You fail for not using diamond one

Defence plan of Yokohama Base.

Despite the ferocity of the attack, the BETA emerged again just outside of Yokohama Base at the No. 1 Runway and the training grounds; both the hordes at Machida and the Secondary Defence Line were diversions, and A-01 and the 7th Battalion were immediately engaged in combat. The F-4Js of Rapier Unit provided support fire while A-01 and the 19th Independent Guard Flight engaged in close-range combat to prevent the BETA from advancing towards the base's entrances.

While both the 6th and 3rd Air Support Units were diverted to the runways, the BETA were pressing the defenders in the training grounds, resulting in some air support being sent to reinforce them. The artillery on the base was destroyed, reducing Yokohama Base's defences to just its TSFs and close air support. Professor Kouzuki then suggested to seal the gates at No. 1 Runway, effectively putting them out of commision for at least half a year, and gathering all available TSF forces to defend the No. 2 Runway and its main gate; her projected goal was to force the BETA to drag out the battle for as long as possible, to increase the chances of the BETA running out of energy and for reinforcements to arrive. As a result, all personnel were evacuated to the second stratum of the base.

On the No. 1 Runway, the F-4Js of Tomahawk, Hermit, Lotus Flight and Gambler Flight were defending the base until the gates could be successfully sealed and hardened. Despite using dead Destroyer-class as temporary walls to prevent the BETA from swarming them, most of the four flights were overwhelemed; Hermit was the first to suffer total losses as Hermit-4 detonated several Supply Containers as impromtu bombs. Despite the ferocity of the blasts and Hermit-4's sacrifice, the BETA quickly filled in the gaps and continued their assault. With one of the gates damaged by the blast, the remaining TSFs were forced to defend the area until an engineering team could remedy the problem. Eight Fort-class BETA then moved forward to attack the gate; in order to stop them, Gambler Flight was forced to engage them up front. In the ensuing battle, Gamble-2's Jump Units were damaged, and she was subsequently killed by numerous Tank-class BETA.

Meanwhile, the Fort-class had began using their acid on the damaged gate in order to force it open; Gamble Flight continued to defend the area, with two remaining survivors from Tomahawk reinforcing them. By this time there were no Lotus Flight members left. With Tomahawk 1 killed en-route, Gamble-1, Gamble-4, and Tomahawk-3 were the only defenders left. With the nearest artillery support from the Imperial Navy's 1st Squadron at three minutes later, Gamble-1 decided to lead the remaining pilots in an attack on the Fort-class near the damaged gate.

At the No. 1 Runway, STF A-01 continued to defend the area against incoming BETA headed for the main gate. With Imperia Navy support secured, STF A-01 and the 19th Independent Guard Flight were ordered out of the area and to prepare for combat against the BETA in the interior of the base. With Yokohama Base's repair and resupply capability for aerial units lost, the 1st to  3rd Air Support Units were diverted to Atsugi Base, while the 4th to 7th Air Support Units were moved to Haneda Base; the 5th Tactical Armored Battalion moved to defend the No. 2 Runway while the Imperial Navy prepared to begin their bombardment of the No. 1 Runway, and the now-abandoned training grounds. Mechanized infantry prepared to engage enemies due to the failure to seal one of the gates at the No. 1 Runway, while the 7th Tactical Armored Battalion regrouped in the base's Second Stratum's Central Area to stage a defence against the incoming BETA.

The BETA came soon enough, engaging Rapier, Grizzly, Circus, Dragon, Joker, Flame, Liger, and Hawk Units of the 7th Battalion with a wave of Soldier-, Warrior-, and Tank-class that had entered from small breaches in the gate. Destroying the first wave, the 7th Battalion then let loose with all their weapons, going as far as to blast away with 120mm rounds against the front of Destroyer-class BETA in the second wave when the gate was fully breached. With plentiful ammunition to spend, the 7th Battalion quickly realized that as much as the Destroyer-class provided good cover, in enclosed spaces the same advantages applied to the advancing BETA.


The aftermaths of combat between the BETA and the 7th Battalion.

The line begain failing as the 7th Battalion entered into melee range with more Tank-class; the close quarters and cover provided by the dead bodies of the second wave's Grappler- and Destroyer-class BETA allowed them to get close. With several TSFs disabled and destroyed by Tank-class the lines began falling; Hawk-4 was swarmed by Tank-class, Hawk-2, who tried to save Hawk-4, started panicking when the Tank-class near Hawk-2 swarmed on him as well, and began to tear him from his F-15.

Hawk-1 immediately jumped to Hawk-2's aid, but the hysteric pilot opened fire indiscriminately, downing Hawk-1. Hawk-4 was next as Hawk-2 opened fire on the Tank-class latched onto the F-15, destroying both the TSF and the BETA. Grizzly-1 immediately ordered Grizzly-4 to disable Hawk-2's F-15 due to friendly fire concerns, but a sudden Tank-class ambush and Grizzly-4's subsequent incapacitation saw Grizzly-3 silence Hawk-2 instead. Hawk-4, distracted by this sudden turn of events, was rammed by a fresh wave of Destroyer-class rushing through the breach.

The 7th Battalion were eventually forced to abandon disabled units and retreat further, and the BETA continued their push towards the main shaft, the quickest way to reach the reactor. The 7th Battalion's survivors joined up with the 5th Battalion and reinforcements from the abandoned No. 2 Runway to prevent even more BETA from entering the shaft. The BETA traveling down the main shaft were immediately engaged by the 101st Mechanized Infantry Regiments; TSF reinforcements identified as Blizzard Squadron were prevented from follwing due to size-to-effectiveness constrains in the shaft.

At this point, the sudden appearance of Fort-class BETA on the now-undefended No. 2 Runway and their deployment of 36 Laser-class BETA as gate destroyers shocked the defenders; the entire battle had gone by without the appearance of a single Laser-class, and even now they ignored the Air Support Units that were currently flying away from Yokohama Base, instead focusing on the main gate at No. 2 Runway. With the decision to seal the 2nd and 3rd barrier gates of the main shaft, all members of the staff were quicky ordered to carry weapons for personal defence, while the BETA at the main shaft, with the help of the Laser-class breaking through the barriers, broke through the 101st, and engaged the 116th and 108th Mechanized Infantry Regiments at the second and third barrier gates respectively. By this time, almost all TSF forces save for STF A-01, the 19th Independent Guard Flight and a few scattered units had been engaged and/or destroyed.

Following this, STF A-01 was re-deployed to shut down the Yokohama Hive Reactor, located underneath the base. The plan called for an operator, who was initially supposed to be Professor Kouzuki herself, to be escorted to the control room and input the shutdown code before retreating to a separate location; two A-01 TSFs will return to the central gathering area, enter the main shaft and follow via the 4th and 5th barrier gates in the main shaft into the lowest stratum to guard the operator from heavier threats. Immediately after, the Moorcock-Lechte Drive of the second XG-70b stored in the base would be activated to draw the BETA's attention, using the sealed gates in the hanger to buy time before they break through and engage the TSFs inside.


Lieutenant Suzumiya on her way to the control room.

Lieutenant Suzumiya Haruka, A-01's operator, eventually volunteered to go on the basis that the risk to the Professor would be too great, and both 2nd Lieutenant Shirogane Takeru and Lieutenant Hayase Mitsuki were choosen as escorting TSFs. The rest of STF A-01 and the 19th Independent Guard Flight, now commanded by Lieutenant Tsukuyomi Mana, would guard Hangar 90. While the orders did not need to be carried out in order, the Professor Kouzuki warned that the Yokohama Reactor had to be shut down within 20 minutes of the Moorcock-Lechte Drive's activation.

Somewhere during this time, the IJA/MDF were finally ordered by the Ministry of Defence to aid the UN forces at Yokohama Base, sending in TSFs under a wave of artillery fire. Advancing from Tamagawa, the IJA/MDF fought through every BETA they could find from Machida to Yokohama, losing two regiments of units due to the differences in numbers; by that time, most if not all of the BETA had emerged from underground.

By the time Takeru and Hayase had reached the second stratum's Central Area, the place had been completely lost to the BETA; roughly 10,000 BETA remained in the interior of Yokohama Base. Rushing through all enemies, the two TSFs quickly sped into the main shaft and engaged Laser-class BETA attempting to break through the gates and the shaft. As Haruka and her escorts at Level B25 continued towards the Yokohama Reactor Control Room at B33, Professor Kouzuki ordered the activation of the Moorcock-Lechte Drive via external power.

Creature System OST go!

The Yokohama Hive Reactor, with the Control Room at Level B33 on the right.

2nd Lieutenant Shirogane and Lieutenant Hayase continued their rush through the shaft at dangerously high speeds for an underground operation, so as to minimize the number of BETA getting through the temporarily opened 4th and 5th barrier gates, using two Surface Jumps to enter the reactor room. However, by that time the BETA had already broken through, and some were recharging using the Yokohama Hive Reactor. As they sniped the BETA in the area to prevent shrapnel damage to sensitive areas, Lieutenant Suzumiya Haruka arrived at the Control Room at B33, which had been secured by security troopers. However, a password error stopped the shutdown program from working; the main and auxiliary cables connecting to the Yokohama Reactor had been severed by the BETA prior to Takeru and Mitsuki's arrival. Professor Kouzuki ordered them to replace the cables, and for Lieutenant Suzumiya Haruka to restart the computer. Despite their efforts, the security troopers were overwhelemed by several smaller strains that had broken into B33 via a maintanence shaft that 2nd Lieutenant Shirogane only found out about much too late; destroying communications with the Yokohama Base Control Room, they eventually breached the Reactor's Control Room, with a Warrior-class BETA killing Lieutenant Suzumiya Haruka and foiling the overall plan.
Too bad, its just more tank and grapplers

Hangar 90 defence plan.

Lieutenant Tsukuyomi Mana, who had ordered the defenders to make a barrier of bodies to choke the entrance to Hanger 90, had engaged the enemy alongside STF A-01; the defenders used short jumps to engage the enemy above the wall of dead bodies that had formed. The BETA then widened the breach into the hangar and increased their numbers, forcing all TSFs to engage them in close combat. However, they were unable to hold back the entire horde, with numerous Tank-class attacking both the active XG-70b and inactive XG-70d. Engaged in close combat, 2nd Lieutenant Suzumiya Akane lost her focus upon hearing news of her sister's death, and was incapacitated by a strike from a Grappler-class.

Meanwhile, Lieutenant Hayase used wired terminals in the lowest stratum to contact the Yokohama Control Room. Updating Professor Kouzuki on the current situation, they were ordered to destroy the Yokohama Reactor in order to force its shutdown. The connection was cut before the Professor could send them the target data, forcing Lieutenant Mitsuki to decide on using S-11s; 2nd Lieutenant Shirogane was ordered to return to the hangar to notify the defenders of the new turn of events, and to turn off the Moorcock-Lechte Drive and defend the Susanoo units.   

Returning to Hangar 90, 2nd Lieutenant Shirogane arrived just in time to save 2nd Lieutenant Sakaki Chizuru from being overwhelemd by multiple Grappler-class, and explain the plan to STF A-01 and the 19th Independent Guard Flight; turn off the XG-70b's Moorcock-Lechte Drive and cause the BETA to move towards the Reactor for Lieutenant Mitsuki to seal the room and let the timers on the planted S-11s do the rest. While trying to shut down the Moorcock-Lechte Drive, the damaged XG-70b collapsed, the impact severely injuring Lieutenant Kazama Touko, who was located next to the unit and was in charge of shutting it down at that time. Fortunately, the Drive shut down at that time, possibly from the power cables being severed by the collapse, and the BETA turned their attention to the last power source; the Yokohama Reactor. With the BETA retreating from the hanger, STF A-01 and the 19th Independent Guard Flight cleaned off the stragglers and prepared to evacuate the wounded and re-seal the hangar; Lieutenant Tsukuyomi then ordered 2nd Lieutenant Shirogane to return to the Yokohama Reactor and tell Lieutenant Mitsuki that she could now evacuate from the Reactor room and let the S-11s do their work.

Meanwhile, Lieutenant Munakata Misae and 2nd Lieutenant Ayamine Kei tried to evacuate Lieuteant Kazama, but her TSF was pinned to the hangar wall by the XG-70b's wreckage. While they were successful in freeing her TSF, Lieutenent Munakata was ambushed by a Grappler-class hiding in the wreckage.

As 2nd Lieutenant Shirogane travelled back down the main shaft, Lieutenant Mitsuki discovered that the BETA had disabled the timers on the S-11s, something that they had never done before. Ignoring 2nd Lieutenant Shirogane's request to delay the detonation due to the possibility that the BETA might have triggered an information breach of Yokohama Base and the Alternative Plans, Hayase that triggered the S-11's explosion herself, destroying the Yokohama Reactor and the BETA within the room. Following 2nd Lieutenant Shirogane's return to Hangar 90, STF A-01 and the 19th Independent Guard Flight procceeded with rescue operations for all base personnel before STF A-01, now comprised of only junior members, were ordered by Tsukuyomi to rest.

With the destruction of the Yokohama Reactor, the remaining BETA gave up the assault and retreated northwest towards the Cheorwon Hive, where they were intercepted by IJA/MDF reinforcements at Kobuchizawa, Yamashi Prefacture, and later at Takayama, Gifu Prefacture. The BETA force suffered 80% losses before escaping into the Sea of Japan, with the 8th IJN Squadron from Maidzuru Naval Base giving chase until 19 33 hours on the 30th of December, 2001, where the naval task force was forced to turn back due to the danger of Laser exposure from the Cheorwon Hive. According to the IJA/MDF, many of the BETA they encounted had simply stopped where they were.


We're on a high~way to luv ~ ♫

The immediate condition of the base personnel after the BETA retreat from the base.

The swiftness of this strike against human assets was both shocking and horrifying for the defenders; never before had the BETA attempted a surgical strike, and Yokohama Base was first-hand proof of what was in store for humanity if the BETA adopted actual battle tactics alongside the standard attrition warfare that they employed. Close air support proved inadequate for the numbers present, and with the heavy reliance on artillery foiled, the BETA quickly gained entrance into Yokohama Base. Professor Kouzuki, banking on the tactical knowledge displayed by the BETA and their single-minded drive towards the main shaft without wandering into other locations in the base, deduced that the BETA in this attack were not only headed by an instinct to seek out a Reactor, but were actually directed by a higher authority; actions like damaging the communications, power cables, disabling the timers on the S-11, keeping Laser-class in reserve and using the dead bodies of larger strains to constantly mask and confuse the human defenders on the current state of base infiltration by the smaller strains could only be explained as such.

As well, due to the speed at which the BETA reached Yokohama Base, it was assumed that the Sadogashima Hive's stabs already extended as far as Gunma, which was in the middle of mainland Japan; this meant that the BETA of the Sadogashima Hive, prior to their destruction in Operation 21st, had been well-positioned to initiate a large-scale strike against Japan within the near future; Shirogane Takeru suspected that the Empire of Japan's failure to properly intercept the BETA in Niigata back in the Unlimited timeline might have been due to the presence of these unknown stabs.

The increased volcanic activity was also a likely cause of late detection and was attributed to the long-term effects of G-bomb usage, as were demonstrated tactics used by the BETA to go underground when advancing in order to avoid artillery fire and needless exposure. The result of failure to detect underground signals meant that the defenders could not anticipate where the enemy could show up, and were complete caught off-guard when the BETA broke conventional battle tactics.

The greatest revelation in this battle was the capability of the Yokohama Reactor, and by extension all the Hive Reactors, acting as an information conduit. While S-11s may or may not have been used at previous Hive operations, they had not made an apperance at Sadogashima; the fact that the BETA from Sadogashima knew how to break an S-11's timer meant that the Yokohama Reactor had given them that information, which itself could have gained it from earlier anti-Hive campaigns, or obtained the information from the 00 Unit during the purification process.

STF A-01 suffered close to 50% of their remaining members as casualties in this battle. Suzumiya Haruka was killed by a Warrior-class while Hayase Mitsuki sacrificed herself to destroy the reactor; Suzumiya Akane, Kazama Touko, and Munakata Misae were all injured, with the latter two sent off to facilities in Kyoto. Initial casualty estimates for the base as a whole stood at over 10,000 personnel MIA or confirmed KIA. The remaining units on the base were close to annihilated, including the artillery, mechanized infantry, and security forces; of all the TSFs, only the Type-00F and -00As of the 19th Independent Guard Flight remained capable of operations, and Yokohama Base no longer had the capability to service air units in any capacity.

The remaining TSFs of STF A-01 that could still stand were no longer combat-capable; the continuous combat and high-capacity maneuvers that they performed had completely worn out a large part of their internal and external systems. Even the spare TSFs that could have been used for parts had been sent out by pilots that had ejected safely and wanted to head back into the action, and by tank crews, former pilots, and all manner of personnel in the defence of the base.

The IJA/MDF, while arriving late, managed to mop up the rearguard of the BETA invasion, with pursuit forces following all the way to the shores of the Sea of Japan, where the Imperial Navy took over. Despite the IJA/MDF's seemingly easy position, they were stretched beyond measure, with no deployment of air units available and an artillery barrage that was a fraction of the force displayed at Sadogashima, before their TSFs charged in. With the loss of two regiments of TSFs, it could be said that the Imperial Army no longer had the capability to fight key defensive battles on the scale of the 2001 Invasion of Niigata or the 2000 Miho Bay Skirmish, essentially leaving all of Western Japan open to a possible second large-scale invasion from the Cheorwon Hive, and making a successful defence of Kyoto, or anywhere in the Empire for that matter, impossible to fulfill.

For Yokohama Base itself, surface damage included the annihilation of the training grounds and the area in and around the No. 1 Runway. The No. 2 Runway remained operational with repairs being effected as soon as the base personnel could, together with the shuttle launchers. Underground damage was also contained, with blast damage from the S-11, gunfire damage, and other general causes ranging from moderate to more serious cases; most of the damage done to Yokohama Base had been to its troops and fighting force, as the BETA had largely ignored most of the facilities in order to reach the Yokohama Hive Reactor.

However, while the battle was a Pyrric victory for the crippled UN 11th Force, the fact that the BETA had gained an information advantage on humanity resulted in the UN accelerating its final plan, and the operation that would represent humanity's first strategic victory over the BETA: Operation Ouka.

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