On a really clear, perfect day for flying without a cloud in the sky, I had a flight from Cherokee County (KJSO) up to Auburn, IN (KGWB), which is about a 4 hour flight in the Malibu. I’ve flown this flight literally hundreds of times, but this day I would not get out of Texas.
As I climbed through 10,000 MSL over Longview, TX, I had a drop in manifold pressure and then got a very weird light…the fuel pressure light. I knew this light told me that I had limited fuel pressure at the engine, so this could be really serious. Not only did it mean I could lose fuel to the engine and possibly lose complete engine power, it also meant that there might be a leak in the system, and the fuel pumps which were running in the fuel tanks could be pressurizing a leak in the engine compartment. Neither scenario sounded good to me.
I immediately reduced power and started a descent for Gregg County Airport (KGGG). To help me lose altitude, I decided to put the gear down, as I was almost on top of the airport and had no question I could glide easily down in case of a complete engine failure. But, when I put the gear handle down, nothing happened! I didn’t get a light or a sound…nothing to make me think the gear had moved at all. Now, I was really confused!
The manifold pressure continued to decrease and ended up not being able to produce over 28” inches of manifold pressure. The gear situation became a primary concern as I was rapidly descending. At about 5,000 MSL, I pulled out the emergency checklist and performed a manual gear extension. I heard the gear drop, it sounded like everything was down and locked, but I had no indication whatsoever in the cockpit.
As I came down, I decided to do a low pass by the tower to let them look at the gear to see if everything looked normal. I figured this was a lesser threat than the manifold pressure/fuel pressure issue. On the fly-by they said it looked normal so I came in and made a normal approach that ended pleasantly.
In the hangar, I found a mechanic and took the cowl off. We found a large bundle of wires on the right side of the firewall that was completely burned through. I thought that I had an electrical issue and so did the mechanic. He spliced each one of the wires, performed a run-up, and decided that everything was working perfectly…or so I thought…
I canceled my trip to Indiana and flew back home to KJSO, about a 40 mile trip. About 20 miles from KJSO, guess what happened? Same exact indication! I responded to the emergency in the exact same manner as I did at KGGG and landed at KJSO without further incident.
Pissed, confused, and weary, I landed at KJSO. I called Kevin Meade and he asked me to go to the cockpit and pull on the cabin heater knob. I really thought Kevin was completely crazy, but he assured me he had a plan. Sure enough, when I pulled the cabin heater knob, it would not move at all. He then asked me about the mixture travel, and sure enough, it was slightly stiff. I was totally confused at this time. What was the issue?
Here’s the answer…I had an in-flight exhaust leak at the cross-over tube at the back side of the engine. The incredibly hot blast of exhaust air (1600F or so) blasted right on the bundle of wires and burned them through. It also blasts right on the heater cable in the engine compartment, melting the silicon in the cable seizing the cable. Same thing for the mixture…the silicon inside that cable had started to melt and partially seize that control as well.
I got to buy a new exhaust system, a new mixture cable, new heater cable, new wires, and a few other lesser items under the cowl. About $12,000 later, I was flying again with a whole new perspective.
1. Call Kevin Meade if you have something weird mechanically! He is absolutely incredible and is undoubtedly the premier Malibu mechanic, bar none. MMOPA pays him as a consultant to answer questions about the Malibu for its members, so don’t feel bad bothering him. He is very approachable and incredibly informative. Put his contact numbers in your cell phone. Within 45 seconds discussion, he had accurately diagnosed the issue on my airplane and directed me in the best manner to have it fixed. The dude is good..
2. Wires don’t burn in airplanes, at least not the little ones. There is simply no way for small wires to cause but burnt areas in the airplane. They can burn slightly and break, but there is just not enough amperage moving through the smaller wires to cause a big event. Starter cables, grounding cables, and other big wires…different story…but the little ones are not going cause such a big issue. I should have known better.
3. Be super cautious of exhaust leaks in a turbo-charged airplane. 1600F is a blow-torch! In C-421’s exhaust leaks have burnt wings off airplanes. I know of one pilot who had a leak on the crossover tube of his Malibu and the fire got so big that he had smoke in the cockpit, had to land off-airport, and seriously damaged an airplane. ALWAYS shake the exhaust before ever getting into a Malibu. If it moves at all, don’t fly! Exhaust leaks are really serious!
4. Don’t let rookies touch your airplane. Granted, I was the biggest rookie by letting the rookie mechanic touch my plane…but still…learn from my mistake and get really good maintenance for your airplane.