Delayed parts shipments are said to be behind the sixth delay to Mitsubishi Aircraft’s regional jet program.

Entry into service of the rebranded SpaceJet is now set for April 2021 at the earliest, although the manufacturer has admitted that it may not occur until fiscal year 2021 “or later”.

Even if the aircraft is ready for the start of the 2021 tax year, that will be more than eight years later than originally planned.

The repeated delays saw supplier Toray, which was to build carbon fiber stabilizers for the SpaceJet, step away from the program in November 2019.

It is unclear whether this was the reason for the latest slippage, but it wouldn’t be the first time that a carbon fiber specialist disrupted an aircraft program.

In 2009 Boeing was forced to take over the South Carolina plant of Vought Aircraft Industries, which produced composite fuselage sections for the 787, while in 2014 Airbus was forced to take over Alestis as the Spanish composite manufacturer ran out of cash developing the belly fairing and tail cone for the A350.

One small benefit from the further delay is that the SpaceJet’s carbon fiber components will have a greater array of inspection and repair technologies available to them once in service.

Recent examples include a robotic arm called LUCIE from Airbus that uses an ultrasonic laser to detect sub-surface defects without being in contact with the composite material, and an automated scarfing system from Lufthansa Technik called CAIRE.

Still, that will be of little comfort to Mitsubishi Heavy Industries, which has just added a $4.5 billion extraordinary loss to the regional jet program in which it has already sunk billions.

It has also replaced Mitsubishi Aircraft president Hisakazu Mizutani with Takaoki Niwa, a former engineer most recently served as president and chief executive of Mitsubishi Heavy Industries America.