Changing aircraft engines

A couple of COPA members have recently found out about an interesting limitation in the CARs. If you put a different type of engine in your owner-maintenance or amateur-built aircraft you have to get a new Special Certificate of Airworthiness!
The Special CofA in these two classes specifies the engine type on that document. This means that if you change the engine type or model, the Special CofA is rendered invalid and you need to apply to Transport Canada for a new one. This isn’t an oversight; Transport Canada purposely put this in the CARs so that they could keep track of the engines installed in Canadian aircraft.
The rules are different for certified aircraft and ultralights. In the case of certified aircraft the engine is not specified on their standard CofA. Transport Canada gets informed of changes in engine types because those modifications require a Supplementary Type Certificate (STC) and TC gets a copy of that for the aircraft file. This is especially important in the case of certified aircraft, as TC may have to send out Airworthiness Directives and so needs to know what engine is installed in your aircraft.
Advanced ultralights have no flight authority document, but are limited by manufacturer’s written approvals. The engine may only be changed for a different type or model if the manufacturer approves that engine for that aircraft or doesn’t specify an engine type. If you install an engine that the manufacturer does not approve of then your aircraft does not qualify to be an advanced ultralight any more.
Basic ultralights have no flight authority, such as a CofA or other restrictions and so you can swap engines without any paperwork at all. This category has the most flexibility in that regard, but it comes at the price of the “no passengers” restriction. Contact Adam Hunt at COPA.