When it comes to aircraft maintenance, few tasks are as high-stakes as welding. A single poor weld on an exhaust flange, engine mount, or intake manifold can spell disaster mid-flight. In Canada, the risks are amplified by a strict regulatory environment. Here, aviation welding isn’t just about making metal stick: it’s about following certified welding standards enforced by Transport Canada aircraft repair protocols.

Whether you're maintaining a classic Cessna or managing a fleet of bush planes, ensuring your aircraft welding is 100% compliant with Transport Canada’s expectations is not optional: it’s the law. 

In this guide, we’ll break down the specific requirements, common compliance pitfalls, and what to look for in a certified aviation welding provider in Canada.

Why Aircraft Welding in Canada Demands More Than Skill

Aircraft welding is unlike welding in automotive, construction, or industrial settings. It demands exacting precision, documentation, and accountability.

Why? Because aviation components must:

• Endure extreme temperature fluctuations
  
  
• Withstand constant vibration and stress
  
  
• Fit into tight geometric tolerances with zero margin for error
  
  
• Meet regulatory expectations for airworthiness and safety
  
  

Every weld on a Canadian aircraft must be completed using Transport Canada–approved procedures, documented thoroughly, and often subjected to non-destructive testing. Simply knowing how to TIG weld isn’t enough.

Transport Canada’s Oversight in Aviation Welding

Transport Canada Civil Aviation (TCCA) is the national authority responsible for enforcing the Canadian Aviation Regulations (CARs). Under Part V, Airworthiness, they establish policies for:

• Aircraft design and modification approval
  
  
• Maintenance organization certification
  
  
• Repair standards for structural and non-structural parts
  
  
• Inspection procedures and record keeping
  
  

If an aircraft part is repaired or fabricated without following these standards, even if it “looks fine,” the aircraft is no longer compliant. That can result in inspection delays, insurance denial, grounded operations, or, in the worst case, mechanical failure.

The Role of AMOs (Approved Maintenance Organizations)

Only AMOs with specific ratings for welding are legally allowed to perform certified welding on Canadian-registered aircraft. These organizations must:

• Be authorized by Transport Canada under CARs Subpart 573
  
  
• Maintain a documented Maintenance Policy Manual (MPM)
  
  
• Employ approved welders working under strict oversight
  
  
• Follow standardized quality control procedures
  
  

Acorn Welding is a Transport Canada–approved AMO authorized to perform structural and non-structural welding on a wide range of aircraft. Every weld we complete is signed off by a qualified inspector and entered into the aircraft’s maintenance record.

Transport Canada – Continuing Airworthiness

What Makes Aircraft Welding “Certified”?

For a weld to be certified under Transport Canada’s rules, it must meet five distinct criteria:

1. The Work Must Be Performed by a Certified AMO

Even if the welder is highly skilled, the work is not certified unless performed under the scope of an authorized AMO. Shops that do automotive or industrial welding cannot legally return aircraft components to service.

2. The Procedure Must Follow a Written Weld Specification

Each weld must follow a Welding Procedure Specification (WPS) that outlines:

• Type of weld (e.g., butt, lap, fillet)
  
  
• Material types and thicknesses
  
  
• Filler metal specifications
  
  
• Shielding gas type and flow rate
  
  
• Joint preparation
  
  
• Preheat or post-weld heat treatment
  
  
• Acceptable weld sizes and penetration depth
  
  

At Acorn Welding, we maintain dozens of WPSs tailored for legacy aircraft exhaust systems, engine mounts, sheet metal repairs, and more.

3. The Welder Must Be Qualified to Perform That Weld

Welders must pass regular qualification tests on the exact processes and positions they will use on aircraft parts. These tests may include:

• Visual inspection
  
  
• Bend tests
  
  
• Radiographic or ultrasonic evaluation
  
  

Welders are typically certified to AWS D17.1 (Aerospace Welding Standard) or an equivalent Transport Canada–approved standard.

4. All Work Must Be Documented and Traceable

Every part we repair or fabricate includes full traceability. That means:

• Unique part ID or serial number
  
  
• Batch number of filler metal
  
  
• Welder identification
  
  
• Date and procedure code
  
  
• Maintenance release certification signed by an authorized person
  
  

This documentation supports airworthiness compliance, audit trails, and resale value.

5. Non-Destructive Testing (NDT) May Be Required

Depending on the criticality of the component, NDT methods like dye penetrant, radiography, or ultrasound may be required. These detect hidden cracks, inclusions, or incomplete fusion not visible to the naked eye.

Pitfalls That Cause Non-Compliance

Even experienced AMEs and maintenance crews can fall into traps when choosing the wrong welding shop. Here are the most common compliance issues:

• Repairs done by non-AMO facilities
  A high-quality TIG weld done outside an AMO means the part is still legally unserviceable.
  
  
• Missing traceability
  No tracking of filler metals, welder IDs, or WPS used? That’s a compliance red flag.
  
  
• Improper documentation
  If the repair isn’t properly released with a Maintenance Release Statement, it can’t go back on the aircraft.
  
  
• Incorrect process for material type
  Welding Inconel with a stainless steel filler rod might look fine, but it will eventually fail and violate certification.
  
  

At Acorn Welding, we mitigate these risks with rigorous internal audits, trained inspectors, and welders who understand both the technical and regulatory side of aviation work.

The Importance of In-House Welding Under AMO Supervision

One key advantage of working with Acorn Welding is our fully in-house, AMO-compliant facility. Unlike general-purpose fabrication shops, we don’t outsource any welding work, meaning:

• Shorter lead times
  
  
• No communication breakdowns
  
  
• 100% traceability
  
  
• Single-source accountability
  
  

This ensures total control over quality and compliance, from initial inspection through welding, testing, and final documentation.

How We Ensure Transport Canada Compliance at Acorn Welding

Here’s a snapshot of how our process aligns with Transport Canada expectations:

Compliance in Action

Example 1: Exhaust Stack Fabrication for a DHC-2 Beaver

A client operating a de Havilland Beaver needed a full exhaust stack replacement. The original OEM part was discontinued.

• We used their old part as a reference for geometry.
  
  
• Our TIG welders fabricated a new stack using Inconel.
  
  
• We matched the original part’s vibration mounts and slip joints.
  
  
• NDT was performed due to proximity to the firewall.
  
  

The part was delivered with a full release and has since flown over 300 hours with zero issues.

Example 2: Engine Mount Repair for a Piper Navajo

A cracked engine mount threatened to sideline a charter operator. Because it was a primary load-bearing structure, Transport Canada required:

• Procedure based on approved WPS
  
  
• TIG weld with documented penetration
  
  
• X-ray testing before return to service
  
  

Our team handled everything in-house, and the part passed inspection on the first try.

Choosing a Certified Welding Partner: What to Ask

Before hiring anyone to weld an aircraft part, ask:

• Are you an Approved Maintenance Organization?
  
  
• What certified procedures do you follow?
  
  
• Do you perform non-destructive testing in-house?
  
  
• Can you issue a Transport Canada–compliant release?
  
  

If they hesitate, walk away. Your aircraft’s safety is not worth the risk.

Looking for Certified Aviation Welding in Canada?

Acorn Welding is Canada’s premier provider of certified aviation welding, exhaust system fabrication, and legacy aircraft part manufacturing. We are a Transport Canada–approved AMO offering full in-house compliance, fast turnaround, and decades of experience in Canadian aviation.

If you're operating an aircraft in Canada, there is no substitute for Transport Canada–compliant aviation welding. At Acorn Welding, we take compliance seriously and we’ve built our reputation on precision, documentation, and in-house quality control.

Whether you’re restoring a legacy aircraft or replacing a cracked exhaust system, our team ensures every weld meets certified welding standards and passes Transport Canada scrutiny.

Contact Acorn Welding to get your parts repaired, fabricated, and back in the air the certified way.