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Armada Technologies’ hull air lubrication system (ALS) is a second-generation ALS that uses the vessel’s own forward motion to drive water through a series of openings in the bow region of the vessel. These openings direct system water through branch lines to venturis and injectors that then “passively” deliver an optimal air / water mix (rather than simply air) for hull lubrication of unparalleled efficacy.

This “passive air lubrication system” or PALS utilizes a small number of low energy pumps and blowers rather than compressors to deliver greater system control and drag reduction optimization that is aligned to the vessel’s prevailing speed, draft and even weather conditions.

PALS passive bubble generation uses the forward motion of the ship and small capacity pumps and blowers. There is no need for the use of continuously-running, high-energy compressions and therefore, needs significantly less power to achieve the optimal effect.

PALS has a performance-augmented control system with “machine learning” for better overall bubble control, meaning the system will self-learn over time to offer greater and greater fuel and emission reduction benefits.


  • The PALS system requires no compressors
  •  PALS uses the forward motion of the ship and small capacity pumps and blowers using significantly lees power
  • The system’s active air / water mix injection mechanism design enables matching bubble production to ship type and operating condition
  • PALS run effectively in all operating conditions (i.e., speed, draft, weather) without the progressive pressure build and “burping” associated with cavity-based ALS
  • The Armada PALS unit is user-friendly and needs no additional staff to maintain the system
  • Because there are no compressors to maintain and fewer equipment parts to service, PALS requires less maintenance than a typical ALS
  • Installation is easier and less costly because it is not encumbered by the integration of compressors
  • Lower capital investment and operating costs provides a quick economic payback to the shipowner


Present-day ALSs use between 3 and 12 air compressors depending on the size of the vessel. These compressors demand significant power to enable the ongoing deliver of compressed air for lubrication. This power must be deducted from the gross benefit of any ALS to derive the net (and true) performance of the system. It is vital for any prospective shipowner considering ALS to consider the impact of this additional power demand on the global load balance of the ship as an integrated system. The power required to run an active ALS is generated via onboard auxiliary engines (4-stroke) or, less commonly, via a main engine shaft generator. In either case, the load balance to accommodate the additional power demand of the active ALS, may well augment the effective load on any single auxiliary engine; in some instances, requiring these engines to run off optimal (on SPOC curve).

Additionally, due to the high number of compressors needed to run the ALSs there is a higher-level breakdown risk, increased noise and vibration on the ship, and additional costs for equipment and maintenance.

Economic Value
Lower investment & operating costs
Hull Lubrication

Bubble size can be homogenized through the careful control of fluid speed through the system and , therefore, the shear stresses prevailing within the throat section of the venturi. Similarly, the system injectors enable the development of a consistent bubble carpet distribution on the bottom plating of the vessel. The net result in unfluctuating lubrication over a wide range of speed and depth variables.

Simple installation & maintenance – no compressors
Passive Bubbles

Runs effectively in all operating conditions such as speed, draft and weather

AI Control

PALS has a performance augmented control system with “machine learning” for better bubble control

Reliability of PALS Technology

PALS went through Hydrodynamic & Cavitation Tunnel (HYKAT) testing at HSVA in 2022.  The results verified that passive aeration by PALS is viable and offers credible double-digit, on-plate drag reduction.


The Armada PALS is expected to be available to shipowners to install by Q4 of 2023

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