Installation in DHC-2 aeroplanes not originally equipped of an artificial stall warning system - Civil Aviation Safety Alerts (CASA) No. 2014-02


Owners, operators and maintainers of Viking DHC-2 aeroplanes and other aeroplanes not equipped with an artificial stall warning system

Issuing Office: National Aircraft Certification
Document No. : CASA 2014-02
File Classification No. : Z 5000-35
Issue No. : 01
RDIMS No. : 9126820
Effective Date: 2014-07-17


The purpose of this document is to advise of the availability and recommend the installation of an Artificial Stall Warning System on all DHC-2 Beaver series aeroplanes and to advise of the enhancement to safety offered by installing an Artificial Stall Warning System where available.


When the de Havilland DHC-2 "Beaver" was originally certified, an Artificial Stall Warning System was available but not installed on all models. An Artificial Stall Warning System for the DHC-2 MKI was originally offered as MOD 2/973. This system was a prerequisite to aeroplanes furnished with agricultural spraying equipment and some aeroplanes delivered to the US Army. All DHC-2 MKIII "Turbo Beaver" were factory provisioned with an Artificial Stall Warning System that was very similar to the one offered as an option for the MKI Beavers.

Stalls encountered during critical phases of flight often have disastrous consequences. An Artificial Stall Warning System providing visual, aural, or tactile warning can give pilots a clear and compelling warning of an impending stall.

Viking Air Limited has developed an improved Artificial Stall Warning System under MOD 2/1605 based on the legacy Artificial Stall Warning System installation. The modification includes the original wing leading edge lift detector, a stall horn and stall light incorporating a push to test feature.

Recommended action:

Although the historical accident rate does not indicate that there is any particular stall-related problem with the DHC-2 Beaver when it is flown within its certified envelope, the installation of an Artificial Stall Warning System can enhance operational safety. Therefore Transport Canada recommends all DHC-2 aeroplane owners incorporate Artificial Stall Warning System MOD 2/1605, or other approved Artificial Stall Warning System.

Transport Canada further recommends that where possible, all owners and operators install an Artificial Stall Warning System in aeroplanes not originally equipped as such.

Contact office:

For more information concerning this issue, contact a Transport Canada Centre; or contact Paul Jones, Continuing Airworthiness, Ottawa, at 613-952-4357, facsimile 613-996-9178, or e-mail


For the electronic version of this document, please consult the following Web address

For the Director, National Aircraft Certification

Original signed by

Robin Lau
Acting Chief, Continuing Airworthiness

The Transport Canada Civil Aviation Safety Alert (CASA) is used to convey important safety information and contains recommended action items. The CASA strives to assist the aviation industry's efforts to provide a service with the highest possible degree of safety. The information contained herein is often critical and must be conveyed to the appropriate office in a timely manner. The CASA may be changed or amended should new information become available.