WestJet Picks Fuel Tank Modification Option For 737 Fleet

Aug 18, 2023

Canadian LCC WestJet’s Boeing 737 fleet will undergo fuel tank modifications to maintain compliance with the FAA’s Fuel Tank Flammability Reduction (FTFR) Rule.

The Calgary-based airline has selected Jetaire Group’s Invicta product, a lightweight, proprietary reticulated polyurethane foam solution that lines fuel tanks to suppress fuel ignition. Invicta’s foam-based kit fills the oxygenated space in a tank and inhibits fuel movement, which prevents changes in weight distribution and friction that could result in a spark.

Canadian MRO provider KF Aerospace will provide installation of Invicta under its recently announced agreement with Jetaire to jointly market Invicta to Canadian customers. Jetaire has previously told Aviation Week that installation of Invicta takes approximately 2-4 days to install on a narrowbody aircraft and 4-5 days to install on a widebody. It says these installations are quicker and simpler than other fuel tank inerting products.

There are several other products on the market to mitigate the fuel tank flammability issue. AerSale offers a similar foam-based product called AerSafe, which entails installing fuel tank-formed inserts to limit the amount of available oxygen. Honeywell offers an air separation module kit for retrofits, and AeroParts has developed several options, including an air separation module repair and nitrogen-generating system.

The FAA’s FTFR rule requires certain transport category aircraft to incorporate flammability reduction means, such as nitrogen inerting, or an ignition mitigation means, such as the aforementioned foam solutions. Many of the corresponding FAA-issued airworthiness directives for aircraft without flammability reduction or ignition mitigation means—which require modifications to comply with the rule—have looming compliance deadlines in 2026.

Jetaire recently received Transport Canada approval of its supplemental type certificate (STC) for installation of Invicta on Boeing 737NG aircraft. The STC brings aircraft into compliance with FAA airworthiness directive 2020-18-13, which requires modifying the fuel quantity indicating system on Boeing 737-600, -700, 700C, -800, -900 and -900ER series aircraft to prevent development of an ignition source inside the center fuel tank due to electrical fault conditions. Jetaire says the product also ensures compliance with regulations such as FAR 25.981 and 121.1117, which relate to fuel tank explosion prevention and flammability reduction.

Jetaire has FAA approval for Invicta installation on 737s, 757s and 767s and Airbus A320 aircraft. It is working on STC approval for Invicta on 777 and A330-200 series aircraft. Jetaire expects to complete its STC for the A330-200 in August or September, and it has begun taking pre-orders for kits. Meanwhile, it anticipates completion of the 777 STC by the third quarter of 2024.

Jetaire also holds regulatory approvals for Invicta from the European Union Aviation Safety Agency, National Civil Aviation Agency of Brazil and Mexico’s Agencia Federal de Aviacion Civil.

Lindsay Bjerregaard is managing editor for Aviation Week’s MRO portfolio. Her coverage focuses on MRO technology, workforce, and product and service news for AviationWeek.com, Aviation Week Marketplace and Inside MRO.