This week, Airbus got a brutal reminder that even the world’s most-delivered jet — the A320 — isn’t immune to shocks as disparate as solar flares and flawed metal.

Days after recalling 6,000 A320-series planes over a software glitch linked to cosmic radiation, the European giant was forced to slash delivery targets when defects surfaced in some of their fuselage panels.

The twin setbacks — one rooted in astrophysics, the other in basic metallurgy — underscore how fragile success can be for a planemaker that dominates the busiest corner of aviation and is on track to outpace Boeing for a seventh straight year.