Germany has grounded its Tiger attack helicopter fleet due to defective material being used in a vital component in the main rotor.
By Alan Lebeda [GFDL 1.2 or GFDL 1.2], via Wikimedia Commons
Der Spiegel says the titanium material in a bolt could become brittle and break apart in flight, the bolt is used in the main rotor control. The problem also exists on NH90 and EC135 helicopters but the material is used on non-safety critical areas.
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