A reminder to aircraft owners, and engineers, to report defects that are affecting modifications, to the relevant design organisation.

In a recent occurrence reported to the CAA, cracks were discovered in a spray boom, and during the removal of the boom for replacement, even more cracks were found.

The engineer also reported the defect to the boom’s designer.

“That’s exactly the right thing to do,” says CAA Safety Investigator Sam Stephenson.

“But problems in service are not always reported back to the supplementary type certificate holder. I think sometimes there’s a ‘let’s just fix it and get on with it’ approach.

“But it’s important for the designer to know if there’s a weakness in their product’s design, or materials. How else can they improve it, and let other operators know about it?”


On the CA005D Defect Report [PDF 82 KB], there’s a tick box for “Manufacturer advised”. You use this to tell the CAA you’ve also reported the problem to the designer.

“If other participants find the same problem, we can work with the designer/manufacturer to issue a continuing airworthiness notice, so others can be made aware of the potential problem,” says Sam.

“If it was someone else who’d identified an issue with an aircraft you operate, wouldn’t you want to know about it?

“Also, the designer needs to stay on top of the reliability of their product, and if a participant has valuable information about that – for obvious safety reasons, they should pass that on.”

It’s usually the maintainer filing CA005D forms and notifying the original equipment manufacturer (OEM) of any faults. But because airworthiness issues are the responsibility of the aircraft owner or operator, they should always check this has been done.

Sam says the important thing is that issues in mods are reported – to both the CAA, and the designer.

Posted in Engineering and maintenance, Aircraft owner and aircraft;

Posted 8 months ago