Vulnerability

Player Owned Customs Offices have their own different reinforcement mechanic. See Player Owned Customs Office for more details on that

Vulnerability is a game mechanic used by most deployable structures to encourage large, planned fleet engagements and enable both attacking and defending groups to more effectively and fairly engage in structure warfare.

• Structures cannot be affected by any form of Electronic Warfare.
• The structure will limit the amount of damage its armor and hull can take per second as defined by its damage cap attribute. This damage cap cannot be exceeded and dealing more damage will result in the excess damage hits being reduced or showing as zero (hits will say "deflected").
• When the structure is damaged it will have 15 (shield/armor) or 30 minute (hull) repair timer. If the repair timer reaches zero the structure will heal completely to full shields.
• To pause the repair timer the structure must receive damage that is at least 10% of the damage cap after resists.
• The defender chooses the time when the reinforcement ends, attacker chooses the day at which the reinforcement ends.
• The ±3h variation in the reinforcement exit times will never cause the fight to "roll over" to next day. The time of shield reinforcement fight will determine the dates of armor and structure timers.
• The reinforcement times are determined from the moment repair timers start. Whether the fight lasts for 20 minutes or 10 hours has no impact on the reinforcement times.
• Structures can be fitted only when it has full shields. The fit can not be changed while the structure is anchoring, onlining, repairing, under attack or reinforced.

While vulnerable the current status of the Citadel is shown on the damage indicator.

• 
  Citadel damage indicator

The outer grey/red circle shows the current damage. It has one section for shield (top), armor (lower left) and structure (lower right). In each section a dot represents 1/12th of full health. A grey dot means intact, a red dot means damaged. So in our example there are only 2 grey dots left on the lower right section, which means the Citadel has only about 17% (2 x 1/12 x 100%) hull left.

The inner yellow circle shows the repair timer. In our example it has about 2/3 of the 15 mins left. One can hover with the mouse over the Citadel damage indicator and it will display how much time is left on the repair timer and whether it is running or paused.

Deployment cycle

When a structure is deployed it has only structure HP. It has no armor or shield.

Immediately after deploying the structure will start to anchor and is vulnerable to attacks. At this stage the structure can be killed without any timers.

The anchoring timer lasts for 15 minutes. If the structure is receiving damage more than 10% of its damage cap the anchoring timer is paused.

Once the anchoring timer reaches zero the structure is reinforced and becomes unattackable.
This reinforcement lasts for 24 hours.

Once the structure comes out of reinforcement it again becomes open to attack, and once a Quantum Core is inserted it starts a 15 minute long onlining timer. If the structure is receiving damage more than 10% of its damage cap the onlining timer is paused.
While onlining the structure has only structure HP. It has no armor or shield and it can be destroyed without any additional timers.

Once the onlining timer reaches zero the structure fully heals its structure, armor and shield HPs.
At this point the structure is fully operational and can be fitted.

Reinforcement cycles

The owner of the structure sets the reinforcement hour for the structure. This is used for determine when armor and hull reinforcement cycles end. Structure and hull fights will always occur at this set time ± 3 hours.
Attackers can see the reinforcement hour by hacking the structure with a data analyzer.

Structure reinforcement cycle flowchart

The default state of an Upwell structure is to be at full shield. At this state the structure is attackable.

Structures in abandoned state (no fuel used for 7 days) have no reinforcement cycles. Those structures can be destroyed in single attack. The repair cycles are still the same 15 minutes for shield/armor and 30 minutes for structure.

Once damage has been taken the Upwell structure will begin a 15 minute repair timer that upon completion will fully repair the structure. This timer however is paused while the structure is taking damage at least 10% of its damage cap.

Once the shields are depleted medium/large/extra large structures with online service modules enter armor reinforced state and becomes unattackable. FLEX structures, abandoned structures and Large/X-Large structures with no online service modules (so it is in low power state) skip armor reinforcement and go straight to vulnerable armor phase. Being low power does not change the reinforcement phases for medium structures.

The armor reinforcement duration varies by structure and space type.

Armor reinforcement duration
	Wormhole	Nullsec/Lowsec	Highsec	War HQ
Medium	Next chosen hour 2.5 d later ± 1.5 hours jitter	Next chosen hour 3.5 d later ± 1.5 hours jitter	Next chosen hour 4.5 d later ± 1.5 hours jitter	Next chosen hour 24 h later ± 1.5 hours jitter
Large/XL	Next chosen hour 24 h later ± 3 hours jitter

Once the structure comes out of armor reinforcement it will start a 15 minute repair timer that upon completion will fully repair the structure to full shield. Again the timer is paused by dealing at least 10% of the damage cap.

Once the armor is depleted Large, XL and FLEX structures enter structure reinforcement and become invulnerable. Medium and abandoned structures skip the structure reinforcement state and go straight to vulnerable structure.

Hull reinforcement duration
	Wormhole	Nullsec/Lowsec	Highsec	War HQ
FLEX	N/A	Next chosen hour 30 minutes later ± 30 minutes jitter (0.5-25.5 hours)	N/A	N/A
Medium	None After armor depleted, hull immediately vulnerable
Large/XL	Next chosen hour 1.5 d later ± 3 hours jitter	Next chosen hour 2.5 d later ± 3 hours jitter	Next chosen hour 4.5 d later ± 3 hours jitter	Next chosen hour 24 h later ± 3 hours jitter

Once the structure comes out of structure reinforcement it will start a 30 minute repair timer that upon completion will fully repair the structure to full shield. As you may already guess you need to deal at least 10% of the damage cap to stop the repair timer.

Once the structure is depleted the Upwell structure is destroyed.

Structure States

Structures can be in one of several states. The state affects various aspects such as vulnerability to attack, tethering, reinforcement timers, and may be slightly different depending if it is a Medium or Large Upwell Structure. When coming across a structure in space, clicking on it will show you its current state - reference this table for what it means.

States can be seen when clicking on a structure in space

State	Features/Effects	Notes
Vulnerable	Open to be attacked Docking is available Tether is available Reinforcement timers are as normal Asset Safety in K-Space is available	The default state. All Upwell structures when properly fueled with a core and a module online will be in this state.
Anchoring	Invulnerable Cannot dock No Tether	Shown in the 24 hour period after an Upwell Structure is placed before a core is able to be added to it. There is an initial 15 min Repair timer, then the 24 Hour Anchoring period. Afterward the structure displays 'No Core' until the core is inserted, and then another 15 min repair timer begins. During each Repair timer the structure can be destroyed outright. Once the core is inserted the Structure enters the 'Low-Power' state until a Service Module is Onlined (with fuel) at which point it enters the standard 'Vulnerable' state.
Un-anchoring	Vulnerable Docking available Tethering available	When a Structure has been decommissioned by the owner, it enters a 7 day Un-anchoring state. It can be stopped at any time during this 7 day period by the owners. There is no way to tell when a Structure will come out of un-anchoring and be available to be picked up. When the un-anchoring timer ends, the Structure appears immediately in a container, along with another container containing the core and any modules/armor/fuel. Rigs are destroyed. All contents belonging to players will be subject to Asset Safety in KSpace / spill into space in Jspace.
Reinforced	Invulnerable Docking is available Tethering is available Lasts a variable amount of days +/-x hours from a time set by the owner (day and hour amount differs by Security Status of the system the structure is in) In the reinforcement period between the initial attack and the vulnerability of the Armor layer, Services can still be used (Clone Bay, Trashing items, ect) If the Armor has been removed then Services are no longer available (Clones cannot be accessed, industry jobs are paused, items cannot be trashed, ect)	Present during the periods after the Structure has its Shield (and/or Armor for Large Upwell Structures) entirely removed, until it comes out of Reinforcement for the repair window. For Large and XL structures, after the Armor has been destroyed and the structure is in the reinforcement window until the Hull vulnerability, Structure Services are no longer available For Medium structures, Structure Services stop being available the moment the hull begins to take damage during the final repair timer (as Medium structures have no reinforcement period between Armor and Hull)
Repairing	Vulnerable 15 min timer Docking is available Tethering is available	Shown during the timer window after a reinforcement period or after a Structure is done anchoring. After a reinforcement period the next layer of HP is able to be attacked - Armor + Hull for Medium structures, and Armor or Hull, for Large and XL Structure If a minimum amount of DPS is applied, the timer is paused. Structures also have a damage cap during this period. If the timer finishes, the structure repairs entirely back to full HP It is also shown initially after the deployment of a new structure, before the Anchoring period, and after the Core is inserted.
Low Power	Medium Structure: No differences Large and XL Structures: The Hull becomes vulnerable to being destroyed at the same time as the Armor, removing an entire reinforcement period Docking available Tethering available	If no service module is onlined or the Structure runs out of fuel (causing service modules to go offline) then the Structure will enter Low Power mode Any module being onlined will immediately cause the Structure to re-enter Vulnerable state
Abandoned	Vulnerable Docking available No Tether No Asset Safety No Reinforcement timers	Happens when a Structure has been in Low Power for 7 days. Onlining any Service Module when a Structure is in Abandoned State will immediately return it to Vulnerable The lack of Asset Safety means a structure in any area of space that has gone abandoned will drop everything into space when destroyed.
No Core Present	Special State Similar to Low Power Tether is not available	When there is no core in a Structure, it shows this. Most often seen just before a core is added to a Structure. As it has no core, it cannot be fitted and so cannot have any online and fueled modules, and so it falls into the "Low Power" state as well (and will show both at the same time). There is a possibility for a structure to have No Core, but also have online Modules - these are legacy structures placed before having a Core was required, and have somehow still remained in such a state in the years since this change was required. Note, such a structure will have online Modules, but no tethering, repair, or fitting services. Because the core always drops when a Structure is destroyed, this informs would be attackers no core is present to be dropped

See also

• EVE help center: Upwell Structures Vulnerability States