Airbus A220 operators have been told to inspect fuel feed tubes for chafing caused by a clamp that, in extreme cases, could inhibit fuel from flowing to engines.
A Transport Canada (TC) airworthiness directive issued May 13 said that operators have reported wear damage “on multiple airplanes” caused by bonding clamps contacting the tubes. "In one incident, the wear damage ultimately led to a hole in the main engine feed tube located in the collector tank, resulting in fuel imbalance during flight,” TC said. Worst-case, such wear could cut fuel flow to engines, TC added.
The regulator ordered affected operators to inspect A220 right- and left-tank fuel feed tubes within 1,800 flight hours of the directive’s May 27 effective date and “rectify any discrepancy.” It also requires repetitive checks every 1,800 hours.
TC based the directive on a March service bulletin issued by C Series Aircraft Limited Partnership, the Airbus/Bombardier joint venture that produces and supports the aircraft. The directive covers all A220-100s and -300s.
No Canadian operators have taken delivery of the A220, but the directive is likely to be adopted by other regulators whose countries have A220s on their registries.
Operators have taken delivery of 68 A220s, Aviation Week’s Fleet Discovery database shows. Europe has the most in service, as Swiss International operates 28 and Air Baltic has 17. Aviation safety in both carriers' countries, Switzerland and Latvia, is overseen by the European Aviation Safety Agency (EASA).