Squawk Box

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts.

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The crew of a Beech E90 King Air experienced a loss of empennage flight controls, which resulted in total loss of aircraft control, and the airplane crashed into a building during an instrument approach. The six occupants sustained only minor injuries.

Investigators looking into the crash found the problem may have begun under the floor at a heater register forward of the lavatory.

Two inches from the heat ducting is a tubing that supplies pneumatic pressure to the deice boots on the empennage. The heater register was at fuselage station 277. The pneumatic tu…

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”

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Textron Lycoming engines have come under scrutiny again, this time for crankshaft counterweight pilot holes that were out of round, resulting in the possible failure of the crankshaft counterweight bushings or counterweight ears.

The FAA has issued a Special Airworthiness Information Bulletin to help operators identify abnormal crankshafts and prevent premature engine failure.

Lycoming manufactured an unknown number of nonconforming crankshafts, and five have failed in t…

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”

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Virtually any aircraft may be subject to fuel contamination following the discovery that certain filters used in fuel farms and fuel trucks may deteriorate.

Velcon Filters Inc., maker of Aquacon and CDF cartridges, has determined that some of its filters would, under some circumstances, allow some of the gelatinous water-absorbing media to pass with the fuel.

As water is absorbed by the water-absorbing media, similar to whats used in baby diapers, the differential press…

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”

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An aircraft owner delivered a Kidde Dexaero fire extinguisher to an FAA-certificated repair station for a hydrostatic test and overhaul.

After a receiving inspection, the unit was routed to the production department so the necessary work could be performed. The unit was found to be full of extinguishing agent and was purged.

While disassembling the fire extinguisher, the technician noticed that the yellow outlet rupture disk had been fired, even though the cylinder was…

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”

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After an accident in which a helicopter crashed and burned, NTSB investigators discovered that the hose used to refuel the aircraft had decomposed internally and leached a gummy resin into the fuel. The contaminated fuel clogged the carburetor jets and the helicopter lost power on takeoff.

The truck-mounted fuel hose was a 30-foot terra-cotta colored hose labeled Versicon which the owner had acquired as a replacement hose from a local supplier in August 1997. The owner re…

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”

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When auditing a propeller repair station recently, the FAA discovered that certain alignment and inspection procedures had not been accomplished in accordance with the manufacturers propeller overhaul manual procedures.

Although there have been no reports of failures of the propellers, overhauled by Santa Monica Propeller Service from January 1997 to March 1999, the FAA considers it a significant safety risk because a propeller failure can lead to catastrophic loss of airc…

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”

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Some current production aircraft and replacement fuel cap kits include metal retention chains. These aircraft, often not originally equipped with any type of fuel cap retention device, were not certificated to meet the lightning protection rules that are currently required. The current required lightning certification criteria, explained in FAA Advisory Circular 20-53A, recognizes the contribution of metal chains to the potential of fuel tank explosions induced by lightning st…

Some of the following information is derived from the FAAs Service Difficulty Reports. Click here to view “Airworthiness Directives.”

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After the air combat simulation accident involving a Beech T-34, the FAA issued an AD limiting the airplanes aerobatic flight. As part of the investigation into the accident, the FAA has determined that a number of T-34s have been imported into the United States that have been sufficiently modified so that they no longer meet the original type design.

Over the years since the aircraft was originally produced, many of them have been exported and used by foreign governments for military missions or…

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”

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A certificated air carrier recently reported a reduction in engine power that was later traced to a stuck turbocharger wastegate. When the incident was reported, the FAA issued Safety Recommendation 99.397, which prompted the manufacturer to issue a service bulletin describing how carriers should inspect the wastegates.

While Part 91 operators are not required to meet the requirements of the SB, the FAA encourages all operators of turbocharged aircraft to conduct at least an…

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”

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Following on the heels of an airworthiness directive and an earlier warning about aerobatic flight, the FAA is continuing its investigation into fatigue on T-34s used in air combat simulation.

After the April 1999 accident that followed the in-flight wing separation of a T-34A Mentor, a metallurgic examination found structural fatigue cracks at several of the fracture surfaces. An examination of the left wing, which did not separate from the airplane, also displayed fatigue…