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Honeywell 737 ASM Lasts Longer, Performs Better, Saves Money

Honeywell 737 ASM Lasts Longer, Performs Better, Saves Money

Honeywell changed the game when it comes to fuel-tank safety by pioneering Nitrogen Generation Systems (NGS) more than a decade ago. The NGS, which all-but eliminated fuel-tank explosions, relies on a critical component called the Air Separation Module, or ASM.

The ASM separates the oxygen from bleed air from the main engines to produce nitrogen-enriched air, which is then delivered to the fuel tank. This creates an in-tank atmosphere with less than 12 percent oxygen, far below the 21 percent level found in the outside air, and too low to enable any fuel vapors to ignite.

Honeywell engineers have been leading the way in ASM advancements that improve the module’s performance, extend service life and reduce maintenance cost for the airlines. Last year we introduced an ASM developed to meet the specific demands of the Boeing 737 aircraft environment.

While several suppliers provide alternate components within the NGS, we are the sole provider of the NGS system, giving us a deep understanding of the function and control laws critical to mission readiness for the Boeing 737. Our ASM was engineered to fit seamlessly as part of the integrated Honeywell air management system, which is standard on all 737-series aircraft.

The Honeywell ASM is designed to meet the unique needs of 737 operators who often fly short routes and execute quick turn-arounds. It is available today as an aftermarket solution when airlines need to replace the module, either upon failure or as part of their preventive maintenance process.

As part of the ASM development process, we met with Boeing and many 737 operators to discuss their needs and expectations. Their overwhelming complaint was about the ASM’s expected service life.

Current ASM offerings generally fail after about three years or between 9,000 and 12,000 hours of operation, requiring unscheduled removal and replacement. The result is higher cost and unplanned downtime while the module is removed and replaced, a process that takes 10 to 12 hours. 

Honeywell’s ASM significantly extends the module’s service life. We offer a seven-year warranty, enabling airlines to incorporate routine ASM change-outs into their regularly scheduled heavy-maintenance intervals. In addition, the ASM can now be included along with the NGS in a Honeywell Maintenance Service Plan.

Our module significantly outperforms the standard option. Even toward the end of the seven-year warranty period, the Honeywell ASM outperforms a newly installed OEM module by 120 percent under real-world operating conditions.

Installation is easier, too. Thanks to the Honeywell ASM Kit, technicians can install the new ASM unit in half the time – about 6 hours – reducing airline maintenance costs. The kit includes the ASM and an advanced-technology filtration system that removes contaminants typically found in the 737 operating environment before they reach the ASM.

Better performance, longer service life, easier installation and lower cost of ownership make Honeywell’s ASM the ideal aftermarket choice for any Boeing 737 fleet. Contact your Honeywell representative or visit us online for more information.

Sean Kelley
Product Management Director Honeywell Aerospace - Air and Thermal Systems

Sean is a Product Line Director at Honeywell Aerospace where he leads several Aerospace product lines, including Cabin pressure systems and On-Board Inert Gas Generation Systems (OBIGGS) across all Aerospace segments totaling $200M in annual revenue.


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