EatSleepFly said:
How much, if any, risk of fire is there if engine oil is seeping, leaking, spraying, oozing, spattering, or otherwise coming into contact with red hot exhaust pipes in flight? How much would it take to create a real risk and/or cause a fire? Say on a TIO-540 for example. Just curious. Thanks in advance!
Any time you have any flamable substance coming into contact with exaust components it is a problem. If everything with the engine is OK, then you are OK. But the other 90% of the time it's a problem.
The main worry is that an exasust leak could ingnite the oil.
Example:
After overfilling the oil in your Seminole you go flying. The excess oil is vented through the crankcase breather and settels on you exaust manifold and pipes, and every other surface in the cowling. The oil is heated by the hot pipes and gives off flamable vapors. These vapors reach the flange at one of the exaust valves that is leaking. It ignites which quickly spread to the rest of the engine compartment. The fireproffing over the fuel lines which was never properly instaled fails, and the fuel line ruptures.
You now have a gasoline fed fire and have about 60-90 seconds to shut off the source of fuel before either your spar melts in two, or the flames eat through the firewall into the fuel tank, or both.
Did I forget to mention that there is no fire warning system in the PA-44. Your first sign of trouble will be the paint on the cowling blistering, then flames. You have used about 45 of your precious seconds before you can even notice that there is a problem.
Fire is THE biggest danger onboard any aircraft. Nothing else comes close. I constantly hear people talking about how they worry about what will happen if the engine quits, and the FAA requires us to train for it. Yet few CFIs understand, much less teach, how dangerous a fire is.
Oh yeah, the turbocharger in a TIO-540 can reach 16,000 degrees and about 30-40,000 RPM. It's a small bomb under the cowling.
