Sunday, October 1, 2006
An inspection and, if necessary, repair is needed for Raytheon model 1900, 1900C and 1900D airplanes to ensure that the wings don't separate from the airplane, according to an August 31 emergency airworthiness directive (AD) issued by the Federal Aviation Administration (FAA).
AD 2006-18-51 was issued after two aircraft evidenced cracks. The FAA noted that the wing rear spar on one aircraft had undergone the manufacturer's recommended thorough inspection at 17,500 hours time-in-service, but the cracks showed up at 19,126 hours, before the 3,000-hour interval at which repetitive inspections are required.
The emergency AD is effective on receipt, and its actions are considered interim. Further AD action may result, based on reports of the inspection findings. Operators are encouraged to use a strong, high-intensity light when they conduct the inspections.
Don't Look in the Mail
Airworthiness directives (ADs) will be distributed electronically commencing in fiscal 2007 (September 2006) according to an August 21 memorandum issued by the Federal Aviation Administration (FAA). In the meantime, the FAA announces that effective June 8 "we're eliminating unnecessary paper mailings to reduce cost and waste involved."
Specifically, for paper-mailed ADs, only the regulatory text, or "body," will be mailed, not the preamble information. Nor will corrections be mailed to owners and operators. These will be available on the internet.
The FAA explains, "We also add a 'correction' comment to our AD webpage …after we post the AD correction on our web site."
Emergency ADs will continue to be faxed or mailed.
As the FAA says, "We appreciate your patience as we make this transition to electronic distribution of ADs."
Readers offered to reactions, one saying the change is inevitable, the other offering a cautionary assessment:
Reader 1: "Seems to be a logical development. Companies are now insisting that they not have to mail out paper copies of annual reports, prospectuses, and the like, because they are available online. Besides, [with more online and less mailing] the FAA might be able to divert some resources towards being effective in other areas."
Reader 2: "Paragraph 4 of this memorandum says,
'We will no longer mail AD corrections to owners and operators. All AD corrections are readily available on the internet.'
Doesn't this now demand the operator periodically check for potential corrections and ties him/her to the internet and the FAA web site? Failing to do so may result in missing a critical correction. How often must one check? Once a week? Once a month? Doesn't this add a substantial time burden to the operator, and shouldn't that be considered in the economic impact of any AD?
If I have to check, for example, every two weeks and have to spend time figuring out which ADs to check, it seems to me that could amount to a very substantial amount of time over the course of a year. It is an increased burden, in my view.
And now if the operator doesn't check and misses a correction, there is also the issue of a violation:
Sec 39.7 [What is the legal effect of failing to comply with an airworthiness directive?] [Anyone who operates a product that does not meet the requirements of an applicable airworthiness directive is in violation of this section.]
Sec 39.9 [What if I operate an aircraft or use a product that does not meet the requirements of an airworthiness directive?] [If the requirements of an airworthiness directive have not been met, you violate Sec. 39.7 each time you operate the aircraft or use the product.]
This seems to transfer responsibility of ensuring correctness of the FAA to the operator. I suppose one analogy would equate to having surgery or receiving an injection against a deadly disease and handing the patient a card that says, 'Please check our web site in case we used a procedure or an injection that wasn't exactly correct and could be fatal if you fail to detect it. By the way, with all our patients now checking, there may be a substantial delay in accessing our web site. Have a nice day, and thank you for your interest in aviation safety.' "
More Codes to Better Define Wiring Failures
More than 60 codes for wiring failure will replace one generic code used in the Navy. Since the ways in which wire can fail vary (chafing, topcoat flaking, etc.), Navy officials believe the new codes will provide better visibility of the exact nature of wiring problems being encountered by maintainers.
The coding scheme may place the Navy well ahead of commercial practice. In the commercial realm now for about three years, a single code has been used to identify a wiring fault (instead of assigning the problem to a component).
The Navy has decided that Malfunction Code 160, which is defined as "Broken Wires, Defective Contact or Connection," can cover a variety of failures. The 63 codes now used were designed to neck down and identify how failures on wiring are occurring (see box).
According to Navy documents, wiring failures in fleet aircraft were under reported, despite the fact that wiring failures were a source of concern.
Research has also indicated that in numerous instances, many components described with Malfunction Code 799, a failure that cannot be duplicated, were actually experiencing wiring failures.
The wiring failures affected the component, causing maintainers too often to believe the component failed, when in fact the component malfunction masked the real problem of a wire failure. The actual wire failure was never traced, so expensive components were swapped back and forth, and components received maintenance they didn't need.
The Navy's expanded wiring malfunction code descriptions are organized by failure categories and groups so that maintainers can better identify the specific wiring failures.
As Jim Jen-kins, an official with the Navy's aging aircraft program said, "If we continue to inaccurately report wiring failures, then wiring will never receive the needed attention from the naval aviation maintenance community."
The 63 aircraft wiring malfunction codes were developed specifically to identify the root causes of wire failures.
According to Bob Ernst, the Navy's aging aircraft program director, "We need to find out if a wire is chafed, if it's misrouted, if it's a bad solder joint, crimp, or whatever."
According to Jenkins, "With the new malfunction codes, engineers will be able to identify what the failure is and map the right solution to solve the problem."
As one source said of commercial practice, "The reporting even of 'significant aircraft wiring problems,' at least up to a few years ago, was very catch-as-catch-can and at the judgment of the airlines."
However, even the one code for wiring failure means the sort of data-driven safety the FAA espouses will be severely hobbled - for want of data.
More Codes, Better Visibility of the Problem
The Navy has shifted from one wiring failure code to 63 in order to generate more specific data on the nature of the failure:
Before: wiring failures were reported under Malfunction Code 160, "Broken wires, defective contact or connection."
Now: new wiring malfunction codes are used, thereby giving more visibility and attention to aging wiring issues; 63 codes have been promulgated, of which a few are listed here to give a flavor of their specificity:
- Corroded terminals, posts, etc.
- Wires chafed
- Loose solder joints and crimps
- Damaged/defective relays
- Loose/improper or damaged clamp
- Corroded connector/backshell