David Learmount & Julian Moxon / London, Guy Norris / Los Angeles
FLS Aerospace and Ryanair are embroiled in a dispute over maintenance performed on six of the airline's Boeing 737-200s, which the Irish carrier claims it was forced to retire early due to damage caused during paint removal.
The aircraft sustained potentially damaging scribe marks on their fuselages caused by a non-approved paint-stripping technique.
FLS says: "It is unfortunate that Ryanair has publicly associated FLS Aerospace with this matter as there is no evidence whatsoever that these scratches occurred as a result of painting carried out at FLS Aerospace."
The row comes as concerns grow that scribe marks caused by maintenance facilities' use of metal, instead of wooden, instruments to remove paint from lap joints could lead to catastrophic damage to the fuselage.
In September 2003, Ryanair made a statement about the retirement of its 737s, saying that work undertaken at FLS Aerospace was the reason for accelerating the retirements. A month later, the US Federal Aviation Administration issued an airworthiness bulletin saying that scratching on aircraft hulls caused during particular maintenance procedures has the potential to lead to cracking "and subsequent hull loss". It added that a Boeing examination revealed that scribing can lead to cracks 130mm-250mm (5-10in)-long 24,000 cycles after the damage was caused. One aircraft showed cracking after only 22,000 cycles.
FLS Aerospace, which has since sold the Bournemouth facility that carried out the work, says "other aircraft, not painted by FLS Aerospace, have been found to have similar markings and we believe this may be a wider industry issue".
Boeing says it has been asking all operators to inspect all aircraft for scribe marks at all structural edges - including lap joints - between fuselage panels and butt joints forming the circumferential seam between fuselage sections. "We have told operators and service centres not to use sharp instruments to cut off the sealant, and to inspect aircraft for evidence of marks and report back."
Source: Flight International
