New Engine Cowl Anti-Ice Valve

By: Andrew Field Department- Hydro Mechanical Systems, Technical Service Global & Challenger Series

Effectivity: Challenger 300/350 aircraft

ATA 30

Challenger 300 and Challenger 350 aircraft operators should be aware that a new Cowl Anti-Ice Valve (CAIV) Part No. WBG3020G103-003 will be available in the fourth quarter of 2021. 

The failure rate of the previous CAIV P/N WBA3020G103-005 caused unscheduled maintenance, trip delays and missed trips. Investigation has revealed that most reported failures were related to the CAIV jamming in either the closed or open positions.

The new CAIV is currently being operated on select aircraft to validate its reliability before launching it into service. A Service Bulletin will not be required to introduce the new CAIV as it is a plug-and-play unit requiring no change to the electrical and mechanical interfaces, however, to avoid nuisance L/R ENG ANTI-ICE FAIL CAS messages, the new CAIV can only be used in conjunction with the dual pressure switch Part No. WBA3020G107-007. 

All Challenger 350 aircraft are equipped with the -007 dual pressure switch on both left and right engines from production so no further action will be required.  As for the Challenger 300 aircraft, the original -005 dual pressure switch will need to be replaced (as a pair) on both left and right engines with the -007 dual pressure switches even if the new CAIV is installed on only one engine.

The new and old CAIV can be installed in a hybrid configuration.  For example, the left engine can be equipped with the old CAIV where the right engine can be equipped with the new CAIV and vice-versa.  The applicable Illustrated Parts Catalog will be updated when the new CAIV becomes available.