Once again, the Experimental Aircraft Association in July pulled off another great AirVenture fly-in at its home in Oshkosh, Wis. This years event had a little of everything, including torrential rain the Friday evening before Mondays opening day, nighttime air shows and lots of airplanes of every shape, size and purpose. Perhaps because the pre-show rain knocked everyone off-kilter-followed by mid-week heat-the overall event seemed to need more cowbell, but it definitely was worthwhile checking out all the new stuff and checking in with long-time friends.
In the May 2019 issue, I couldnt help but note the connection between Key Dismukes article Stress in the Cockpit and Mr. Burnsides observations in Cockpit Communication. When there is poor communication in the cockpit, stress levels are going to rise. It doesn't matter if the communication shortfall takes place in the air or on the ground. Two of the four categories of errors made by airline crews that were pointed out by Dr. Dismukes were inadequate comprehension, interpretation, or assessment of a situation, and inadequate communication. These categories are faithful descriptions of the failure to explicitly define and communicate expectations that your friend experienced with his flight instructor.
The weight of the engine is only significant in that it is part of the center of gravity of the aircraft, which naturally lies aft of the main gear in a taildragger. Therein lies the problem, especially while landing. That center of gravity, without interference, will travel in a straight line when in motion, according to Newtons First law, which is often called inertia. It is imperative that we keep the airplane (longitudinal axis) tracking and aligned with that same straight line.
For example, a large flying club I was in a few years back had a pair of Cessna Cardinal RGs. They were getting a bit long in the tooth, but were roomy and relatively fast, and they were good cross-country airplanes. They also were configured basically the same, with two nav/comms but little else: no autopilot, for example, GPS or DME. After getting to know them both, I came to prefer the blue-and-white one over the orange version, since it was a bit younger and cleaner. Neither let me down, but one was sold to someone outside the club and, shortly thereafter, another pilot landed the remaining Cardinal RG gear-up.
Receiving inspection of new air filters (p/n P107336) revealed three out of four had a defective sealing surface, causing the sealing/mating surface to crack and crumble. This defective sealing surface could potentially enter the engine. The defective filters sealing surface has a light-gray color while the replacement filters we received, inspected and found to be in serviceable condition had a dark gray, almost black sealing surface. Suspect that the defective filters had improper material on the sealing surface or were improperly cured.
Remember that propeller blades are airfoils moving in a plane different from and usually perpendicular to the direction of flight. As an airfoil, the amount of lift the blade creates when moving through the air depends on its angle of attack, and its angle of attack-plus drag-can depend on a variety of factors, including the airplanes pitch attitude. Remember, too, that the outer portions of long prop blades move faster-they cover greater distance in the same amount of time-than shorter ones.
They expressed their nervousness, which was understandable. Who wants to show their flight skills to a critic when those skills are at low proficiency? It is human nature to want to show your best side, but a rusty pilot flight review will show the naked truth. I explained there is nothing wrong with being out of practice, and a flight review is not a test, but an opportunity to learn. Their anxiety acknowledged, we moved on to the needed practice.
I like to fly at night. The air generally is smoother, theres less traffic, the ATC frequencies are not as busy and ground illumination, the moon and the stars can compete in one of the best light shows youll ever see. Of course, humans were never meant to fly in the first place, and we often have difficulty actually seeing things at night. So we need to be mindful of night flyings risks and adopt procedures or limitations mitigating them.
Normally, I might have panicked, but with my experienced copilot at my side, I stayed calm. We talked through our options and decisions along as I continued to fly the plane. I began a series of small adjustments to the throttle and mixture to see how the engine responded. We quickly discovered these changes only made matters worse, so we left the settings as is. My buddy reminded me to stay high-altitude is our friend-and we looked for landing spots in case things deteriorated.
Knowing of the low overcast, if that pilots autopilot had this auto-capture feature, his motivation would have been to ease his workload and obviate spatial disorientation during transition into the clag. The effect of his action would have been to capture the airport elevation as target altitude. The TruTrak, at least, takes a few seconds to process and implement settings, so that the airplane would be expected to do exactly what it did: ascend into the clouds and a few seconds later return to the preset target altitude of the runway.
As the airplane was vectored to avoid cells and areas of heavy precipitation, the controller queried the pilot about his inability to maintain assigned headings. The pilot reported that his autopilot had kicked off and that the winds are really weird up here. At about 1310, the airplane slowed to about 70 knots groundspeed on a northeasterly heading before it began an accelerating 90-degree right turn to the south. By 1313, the controller again asked, ...appears you've turned back to the northwest and...are you going to turn back eastbound? The pilot replied, I don't know what's going on up here. I'm working on instruments…acting really goofy here. Shortly thereafter, the airplane turned and descended from a northerly heading sharply to its right. The radar track tightened to the right as the target rapidly descended, then disappeared at about 1315 in an area that depicted heavy precipitation.
When we first learned of the breadth of the detonation problem, we contacted XP-400 engine owners and paid to have them ship their engines to our facility for evaluation, Superiors Bill Ross told sister publication Kitplanes. We disassembled, inspected and tested the key components in each engine, he said, but even after adjusting the ignition timing specification, the results were still unsatisfactory. In response, the company decided to ground affected engines and create a buyback program.