China staged a low-key but historic debut of its C919 civil jet at its biggest airshow on Tuesday, with some delegates unable to attend the scaled-down event because of Beijing’s zero-Covid policy as cases reached the highest level in six months.

In a reminder of the continuing health crisis slowing China’s return to global aviation, the organisers of Airshow China in the southern city of Zhuhai had urged attendees to arrive three days early because of Covid-19 precautions.

Even then, some were blocked from joining day one because they had visited a Beijing district that had positive cases last week, three attendees said.

A China-based executive at a Western engine maker said a lot of Beijing-based delegates had returned home in frustration, though some were allowed in at the last minute.

Organisers did not respond to a request for comment.

China’s zero-Covid policy has hampered…