How Does Aircraft Exhaust Systems Affect Flight Safety?

Flight safety and aircraft exhaust systems

An aircraft exhaust system significantly affects a plane’s performance and the safety of passengers. It works by keeping combustion by-products away from the engine while indirectly providing a heat source for the cabin and carburetor. However, a faulty system prevents the engine from functioning properly, or worse, it may cause carbon monoxide poisoning, fire and complete engine failure. 


The importance of ensuring that your aircraft exhaust system is regularly inspected and maintained cannot be overstated. Since exhaust systems are regularly exposed to over 1,000 degrees Celsius and a corrosive environment, their components are prone to leaks and cracking.


If you need FAA- and PMA-approved exhaust system parts or repair services, visit our website, Knisley Welding or call us at (800) 522-6990


Aside from repairing and manufacturing aircraft exhaust systems, we also design and customize spare parts for well-known brands such as Cessna, Piper, Beechcraft, Bell, Helio, and Mooney


Faulty exhaust system and carbon monoxide poisoning 

Aircraft fuel contains carbon that when  burned, produces carbon monoxide, which is an odorless and colorless gas that’s poisonous to humans. Meanwhile, the exhaust system works by pumping this hazardous gas out of the engine. 


But in the case of a faulty exhaust system, carbon monoxide and other poisonous fumes may seep into the cabin, causing symptoms such as weakness, chest pain, dizziness, headache and confusion, according to the FAA website. In large amounts, they can lead to death. 


Fire is another risk that comes with a faulty aircraft exhaust system. Remember that the engine produces a lot of heat, which the exhaust must push out to prevent overheating, cracks and leaks. 


Compared to car and bike exhausts, the aircraft’s exhaust system has a more critical role. Aside from allowing the engine to function at its best, it also acts as a heating system for the cabin, creating a comfortable environment for the passengers and pilots. 


Because of the critical role of the aircraft exhaust system, it requires regular maintenance and inspection in accordance with FAA requirements. 


What are the telltale signs of a faulty aircraft exhaust system?

You don’t have to be a professional aviation technician to perform cabin and exterior inspections. A good rule of thumb is to look for anything that appears mechanically unsound (missing/loose fasteners and rivets). And when it comes to the exhaust systems, watch out for flat gray or sooty black streaks on the pipes. 


However, repairs and maintenance should be left to professional aircraft mechanics. 


These are the other telltale signs of a faulty aircraft exhaust system that you should watch out for when conducting your pre-flight inspection. 

  1. Leaks, cracks and deformed spots on the muffler
  2. Misaligned stacks
  3. Yellowish stain or grayish residue near any exhaust system components
  4. Bent, broken or missing parts
  5. Metal fatigue, thinning or bulges in any part of the exhaust system


Even though there is no visible wear and tear, it doesn’t automatically mean the plane is safe to fly. This is why the FAA requires regular maintenance, which depends on aircraft use. But in general, planes are required to have a complete inspection every year and after every 200, 400, 600 and 800 hours of flying. 


Importance of maintaining and inspecting your aircraft exhaust system

Aircraft exhaust systems are exposed to corrosive elements and high temperatures, making them susceptible to leaks and cracking. In addition, the hydrocarbon fuel, which burns continuously in the system, leaves an acidic residue. With all these elements, certain parts such as the slip joints, cylinder exhaust flange attachments, and clamps are more prone to wear and tear compared to other parts of the engine. 


Due to the corrosive environment and extreme temperatures the exhaust system is exposed to, most mechanics recommend that you hire a professional to inspect it every 1-2 years.


During an inspection, mechanics focus on the mufflers and heat deflectors to see if they have creases, protrusions or thinning. They also look for signs of leakage through a vacuum and soapy water method, feeler gauges and/or pressurized systems.


Knisley Welding: Your aircraft exhaust system expert

Knisley Welding has been serving the aviation community for around 50 years. We have an extensive inventory of FAA-approved exhaust components, including spare parts for brands like Cessna, Piper, Beechcraft, Bell, Helio, and Mooney.  Also, we repair, design and customize replacement parts. 

Please fill out this form or call us at (800) 522-6990 to learn more about our FAA- and PMA-approved exhaust parts and repair services.