Israel Aerospace Industries (Tel Aviv Ben Gurion) has advised all operators of its converted B737 freighters to ground the aircraft due to a potentially unsafe design issue, Reuters has reported. The manufacturer has already submitted a fix for certification with the Civil Aviation Authority of Israel (CAAI).

"IAI has recommended to the aircraft’s operators that they not operate the aircraft until the results of the CAAI's review are known," the manufacturer said.

The potentially unsafe "apparent irregularity" relates to the rigid barrier installed on some of the 47 freighters converted by IAI. It does not affect flights in normal conditions but could potentially do so under extreme circumstances.

"IAI's tests indicate that the rigid barrier may not provide the support it was designed to provide in such extraordinary conditions. The issue does not affect aircraft flight but may limit the way the aircraft can be safely loaded for flight," it said.

IAI did not say how many of its P2F-converted freighters were affected. Reuters has reported that Express Freighters Australia (QE, Sydney Kingsford Smith) has already grounded all four IAI-converted B737-300(F)s operated on behalf of Qantas Freight (Sydney Kingsford Smith).

The Israeli manufacturer is expecting the CAAI to approve the proposed fix shortly.

"CAAI reviewed favourably our interim solution and intend to issue an Airworthiness Directive tomorrow (December 12) which will allow the aircraft to be operated safely," the manufacturer said in a follow-up statement.

So far, the CAAI has not issued any directives related to the type and has not mandated a grounding.

According to its website, IAI is specialised in passenger-to-freighter conversions and has so far delivered over 250 converted aircraft including B737-300(F)s, B737-400(F)s, B737-700(F)s, B747-100(F)s, B747-200(F)s, B747-400(F)s, B757-200(F)s, B767-200(F)s, B767-300(F)s, and MD-11(F)s.