[Peetwo]

FINAL REPORT - In-flight breakup involving PZL Mielec M18A Dromader aircraft, VH-TZJ, 37 km west of Ulladulla, NSW on 24 October 2013

Safety Issues:

Removal of wings to complete service bulletin actions

Although wing removal was necessary to provide adequate access for effective visual and magnetic particle inspections of M18 wing attachment fittings, the aircraft manufacturer’s service bulletin E/02.170/2000 allowed the wings to remain attached during these inspections.

Issue number:

AO-2013-187-SI-02

Who it affects:

Maintainers of M18 aircraft completing CASA AD/PZL/5 and PZL Mielec service bulletin E/02.170/2000

Status:

Safety action pending

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M18 Dromader airframe life factoring

Operators of some Australian M18 Dromaders, particularly those fitted with turbine engines and enlarged hoppers and those operating under Australian supplemental type certificate (STC) SVA521, have probably conducted flights at weights for which airframe life factoring was required but not applied. The result is that some of these aircraft could be close to or have exceeded their prescribed airframe life, increasing the risk of an in-flight failure of the aircraft’s structure.

Issue number:

AO-2013-187-SI-01

Who it affects:

Operators of PZL M18 aircraft

Status:

Adequately addressed

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Spectrum of flight loads

Operation of M18 aircraft with a more severe flight load spectrum results in greater fatigue damage than anticipated by the manufacturer when determining the service life of the M18. If not properly accounted for, the existing service life limit, and particular inspection intervals, may not provide the intended level of safety.

Issue number:

AO-2013-187-SI-04

Who it affects:

All operators of M18 aircraft

Status:

Adequately addressed

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Use of eddy current inspection for airworthiness directive AD/PZL/5

The eddy current inspection used on VH-TZJ, and other M18 aircraft, had not been approved by the Civil Aviation Safety Authority as an alternate means of compliance to airworthiness directive AD/PZL/5. This exposed those aircraft to an inspection method that was potentially ineffective at detecting cracks in the wing attachment fittings.

Issue number:

AO-2013-187-SI-03

Who it affects:

All operators of M18 aircraft that have had their M18s inspected using the eddy current procedure QP.00.36 (EC)

Status:

Adequately addressed

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Adequacy of the eddy current inspection procedure

The documented procedure for eddy current inspection of M18 wing attachment fittings did not assure repeatable, reliable inspections.

Issue number:

AO-2013-187-SI-06

Who it affects:

All operators of M18 aircraft that have had their M18s inspected using eddy current procedure QP.00.36 (EC)

Status:

Adequately addressed

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Civil Aviation Safety Authority records

Important information relating to Civil Aviation Safety Authority (CASA) airworthiness directive AD/PZL/5 was not contained in CASA’s airworthiness directive file, but on other CASA files with no cross-referencing between those files. This impacted CASA’s future ability to reliably discover that information and make appropriately‑informed decisions regarding the airworthiness directive.

Issue number:

AO-2013-187-SI-07

Who it affects:

All aircraft operators in Australia

Status:

Adequately addressed

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Assessment of NDT procedures

The Civil Aviation Safety Authority did not have a defined process for a robust, systematic approach to the assessment and approval of alternative non-destructive inspection procedures to ensure that the proposed method provided an equivalent, or better, level of safety than the original procedure.

Issue number:

AO-2013-187-SI-08

Who it affects:

All aircraft operators in Australia

Status:

Safety action pending

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Australian supplemental type certificate SVA521

The engineering justification supporting Australian supplemental type certificate SVA521 did not contain consideration of the effect an increase in the average operating speed could have on the rate of fatigue damage accumulation.

Issue number:

AO-2013-187-SI-09

Who it affects:

All aircraft operators of the M18 aircraft in Australia operating under STC SVA521

Status:

Adequately addressed

Media coverage

First from Oz Flying:

The Dromader crash site south of Nowra. (ATSB)


Dromader Investigation points to Fatigue Cracks
16 Feb 2016

Fatigue cracks in wing mounting lugs caused the crash of an M18A Dromader firebomber in 2013, according to the ATSB report released yesterday.

Dromader VH-TZJ was in operation as a single-engine aerial tanker (SEAT) over a bushfire near Ulladulla, NSW, on 24 October 2013, when the port wing separated in flight. The pilot died in the accident.

" ... the left wing separated because it had been weakened by a fatigue crack in the left wing lower attachment fitting," the ATSB report states.

"The fatigue crack originated at small corrosion pits in the attachment fitting. These pits formed stress concentrations that accelerated the initiation of fatigue cracks.

The ATSB discovered during the investigation that manufacturer–PZL Mielec–issued instructions to remove the pits, but the pits were not completely removed during previous maintenance. Also, the components were tested for cracks using an eddy current inspection, which was not approved for that particular inspection and may not have detected the crack.

The ATSB report also stated that the way VH-TZJ had been flown prior to the accident could have accelerated the crack growth rate.

"The aircraft had been operated at higher speeds and subjected to a more severe flight load spectrum than assumed by the manufacturer when it determined the aircraft's service life limitation. This likely increased the rate of fatigue damage, increasing the rate of formation and growth of the micro-cracks in the left outboard wing lower attachment fittings."

CASA has since revised the Airworthiness Directive for inspecting the wing attachments to specify magnetic particle inspection.

The full investigation report is on the ATSB website.

Passing strange??- Yesterday the Bloomberg Business article on MH370 - see HERE - quoted the MH370 Super Sleuth Muppet as saying he is consumed by MH370:

Back in Canberra, the ATSB is investigating about 130 incidents in total -- ranging from a freight train derailment in Queensland to a seaplane crash off northeast Australia.

Yet Dolan says he’s consumed by MH370. He speaks mostly in a soft, low tone, pausing often as he chooses his words. At a table in his office, he refers to a map of the search zone in front of him as he outlines the analysis of the plane’s final moments:

Yet in the following ABC article he features as the ATSB spokesperson on the Dromader Final Report:

Undetected stress fatigue crack caused wing to break off in water bombing plane crash that killed pilot David Black


ABC Illawarra
By Nick McLaren
Posted Tue at 9:21amTue 16 Feb 2016, 9:21am


Photo: A Dromader water bomber pictured in flight. (Supplied: Hustvedt)

An investigation report into a fatal plane crash on the New South Wales south coast has found the left wing separated from the plane mid-flight due to an undetected fatigue crack.

The M18 Dromader was carrying out water bombing operations for the Rural Fire Service when it crashed near Ulladulla in October 2013.

The crash resulted in the death of experienced pilot David Black, 43, from Trangie in central-west NSW.

The final report from the Australian Transport Safety Bureau (ATSB) found the wing separated from the plane due to a fatigue crack in the lower attachment fitting, which originated in small corrosion pits.

The corrosion pits were not successfully removed during maintenance, and the unapproved inspection method may not have been effective in detecting the crack.

"The result of weathering, interaction with the metal and so on could lead to corrosion of the metal and that leads to pitting of the metal, and the way of dealing with that is to strip back the metal and remove the pitting," ATSB chief commissioner Martin Dolan said.

"And that wasn't done fully effectively in this case."

The report also noted the harder and faster an aircraft was flown, the more rapidly the structure would fatigue.

Mr Dolan said despite approval to carry heavier loads, the stresses to the plane could have been more accurately calculated.

"There was a range of tests and approvals that were done to allow it to fly with a heavier load," he said.

"But looking back over the various calculations done about that, we think that the risk of parts of the aircraft being subject to stress and fatigue risk was probably under calculated."

Since the accident, Commissioner Dolan said procedures for inspections and recommendations for carrying additional weight were close to being fully implemented.

"They have actually been implemented or are in the process of being implemented, and we'll just keep an eye on them until the work has been complete," he said.

"But we are satisfied with the action that has been taken or the action that's proposed."

The M18 Dromaders are no longer approved for water bombing operations.

Maybe the usual spokesperson was off crook; or due to budgetary constraints has had his/her hours cut back? Probably a good thing because it would seem that the CC (on top of being a MH370 Super Sleuth; & deep sea salvage & search expert) is something of an airframe fatigue & aircraft (NDI) engineering expert...  


MTF...P2