At least 17 China-based aircraft with seats removed will be affected as the country tightens up regulations around the use of passenger cabins to carry cargo.
Last month, the Civil Aviation Administration of China (CAAC) announced that from January the passenger cabins of China-registered aircraft would only be able to carry pandemic related cargo.
Meanwhile, removing seats from aircraft in order to carry cargo in cabin will be prohibited and any aircraft that have had their seats removed will need to be restored to their original configuration.
The new requirements are safety related, the CAAC said. So far foreign airlines have not been included in the new requirements.
According to data from the Cirium Fleets Analyzer there are currently at least 17 China-based aircraft that have had their seats removed, although it is not always possible to identify which MSNs are being used as cabin preighters.
The Cirium database shows that 14 of these aircraft are A330-200 aircraft operated by China Eastern Airlines, another is an A330-200 operated by Air China and the final two are A330-300s flown by Hainan Airlines.
The number of aircraft flown with seats removed has come down since the first quarter when Cirium data showed a total of 27 China-registered passenger aircraft were flying in an all-cargo configuration.
The full-extent of the stricter regulations on cargo capacity is hard to calculate as it is difficult to know how many aircraft are operating with cargo loaded on the seats.