Exhaust Leaks — Headaches for You and Your Plane

There are two things that are given in aviation: First, the cost to fly will go up each and every year; second, if you don’t keep an eye on your exhaust system, it will most assuredly kill you dead!

CASE STUDY: While on an IFR flight, the pilot of a P210 became irrational and then passed out. His wife was able to take the controls of the plane, but she too lost consciousness from the carbon monoxide leaking into the plane. After flying an erratic course, the plane ran out of fuel and crashed. There were no survivors.

The problem with carbon monoxide is that it is a colorless, odorless gas. Since you can’t see it or smell it, you can’t sense it.

The effects can range from causing you to exercise poor judgment, to giving you a headache, to causing you to black out. Whatever the case, if you don’t get it stopped, you may not live to get it fixed!

SMALL BEGINNINGS, BIG PROBLEMS
Most leaks in the exhaust system start out small, and can go unnoticed for some time. If those leaks happen to be hidden inside your heat exchanger and you turn the heat on, poisonous gasses — including carbon monoxide — will be ported directly into your cabin… by your own request.

FOR YOU AND YOUR AIRPLANE.
Take the small leak at the exhaust manifold of your engine. Take note of the things immediately next to the exhaust manifold on many engines — that’s right — intake manifolds. The way the fuel / air mixture is distributed, the cylinders all expect the same density air and fuel.

Example: If the exhaust leak is blowing directly onto an intake manifold, it’s also making the temperature of the air going to the cylinder higher and reducing the density of the air. Translation: Fuel-injected engines will suffer from a lean mixture on that one cylinder — so lean, in fact, that you can burn a valve!

A CANCEROUS GROWTH
If you spot an exhaust leak, get it repaired promptly. Hot exhaust gasses will continue to flow from the crack or hole, and it will grow over time. This constant erosion can eventually cause the entire pipe section to break off or fail in flight. If exhaust is directed into the engine compartment, instead of safely overboard as it was designed to, you will have a bigger problem.

PREVENTION & DETECTION
Preflight
: Look for the telltale gray stains caused by lead in your fuel, which comes out with the exhaust. Don’t fly the plane until any visible holes / leaks are repaired.

Bulges: These areas are weak spots in the exhaust header — one good backfire, and they will split wide open. The amount of fun you will have when that happens is directly correlated to where the hole opens up. Get bulged pipes sent out for repair promptly.

CO Monitors: These inexpensive devices can help to save your life, but only if you look at them, and refresh them on a regular basis. Keep one in plain sight in the cabin and make sure you open up a new one / replace batteries when you need to — they only work if they are used as directed.

Symptoms Awareness: One key sign of CO exposure is a dull, throbbing headache — and you don’t have to be a pilot to feel it, so be sure to include a symptoms rundown in your passenger preflight. If you or your passengers feel headachy and don’t know why… announce your concerns to a controller and get your airplane on the ground quickly.

In Flight DEFENSE: Open up a window or fresh air vent, and shut off any cabin heat to make your chances of success better — even if… especially if… it’s cold outside. The longer you wait to take action, the more likely CO poisoning will take your life — and that of your loved ones!

BOTTOM LINE: SEE and AVOID. Keep an eye on your exhaust pipes. Watch, maintain and refresh your cabin CO monitors. These simple steps will help spot problems before they become a threat to your life. Often, CO is seen as a winter flying problem, but CO poisoning can occur in any season. Stay vigilant throughout the year and you should be able to spot any exhaust problems before they give you or your airplane a headache that you won’t soon forget.