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#OSH19

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.

More Cockpit Stress

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.

IFR Route Changes

Sitting around and talking with pilot friends, you hear nonstop talk about aircraft and equipment. Eventually, someone always brings up ATC in conversation. Pilots argue among themselves more intensely than Socrates debating Plato. One question that new and even veteran pilots bring up is why, when they file an IFR flight plan, that their clearance is usually never as filed but includes a route change of some sort.

Laters And Waiters

In the decade-plus since the coming ADS-B mandate became a thing for U.S. aviation, those whose operations will be affected have fallen mainly into two camps: early adopters and those who put it off as long as possible. In this binary world, I freely admit to being something of an early adopter. And despite some cool-and less expensive-new gear on the market, Im happy with my choice to equip with ADS-B in 2016. Its likely those who have taken a wait-and-see attitude also are happy.

Power And Pitch

If youre like me, youve been watching the ongoing saga of Boeing and its 737 MAX. The gist of it for our purposes is that the new MAX versions of the 737 are powered by larger-diameter engines than the type was originally designed to accommodate. Since the 1980s-when Boeing switched from the types original low-bypass Pratt & Whitney JT8D engines to the CFM International CFM56-the reduced ground clearance when mounting high-bypass powerplants featuring improved fuel economy has required flattening the bottom of the cowlings. It was cheaper and easier than redesigning the landing gear, which is too short to accommodate the larger engines.

NTSB Reports

After a low pass over the field, the pilot returned to land. On final approach, he was blinded by [the] sun and the tailwheel hit vines growing near the airstrip, causing the airplane to stall. The left wing, left main landing gear and propeller were damaged during the hard landing. According to the NTSB, [b]ecause the pilot did not hold a current pilot certificate, nor did he meet the medical certification requirements, he was not legally authorized to act as pilot-in-command of the airplane at the time of the accident.

Flying Your Propeller

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.

Cockpit Communication

I recently had the chance to chat with a long-time friend and pilot about some issues he had with an instructor while working through a flight review. The friend was concerned about the instructors critique of his flying, which included comments like, I didnt expect you to do that, and I would have done it differently. The friend wasnt necessarily complaining about the critique itself but the after-the-fact manner in which it was supplied. Ultimately, it undermined his confidence and he chose not to fly with that instructor again, taking his chances with someone different.

Bad Bushings

Found damage on shock absorber assembly. Damage caused from the top boss contacting the shaft shock absorber shaft. The bushing was discovered missing on three aircraft at the same flight school. The manufacturer was notified of damage, affected parts replaced and the aircraft was returned to service. The quality/airworthiness department is currently reviewing work orders in an effort to isolate aircraft affected by this missing bushing. All three aircraft with missing bushings had between 1300 and 1400 hours total time.

Superior Pulls Engines From Service

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.

Losing Attitude

All other things being equal, one of the benefits of a primary flight display (PFD, which presents flight instrumentation on an electronic panel) is its use of a solid-state attitude and heading reference system, sometimes known as an AHARS. By using an AHARS to determine which side is up and in which direction the airplane is pointed, the vacuum-driven system is avoided and usually only an electrical system failure or failure of the display itself can eliminate the flight instruments. (Certification rules require backup flight instruments when a PFD is present but not when steam gauges are energized by a vacuum pump.)

NTSB Reports

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.