Supply chain problems are slowing the delivery of already delayed jets at Boeing. The US aircraft manufacturer has a backlog of 5,189 planes and was already grappling with longstanding problems with delivery timelines. But with building a Boeing involving thousands of individual items coming from different suppliers, ongoing supply chain problems are threatening to further blow out aircraft delivery times.

Supply chain problems slow down 737 MAX assembly

Boeing's delivery problems with several of its aircraft programs are well documented. The 777X program is running years behind schedule, and ongoing issues with the 787 Dreamliner have seen deliveries of that aircraft paused since June 2021. Despite its long-running grounding, the 737 MAX is emerging as Boeing's great white hope. But getting those planes out the door is also starting to prove a problem.

Boeing specialist Dominic Gates at The Seattle Times reports that a shortage of certain materials caused by rolling supply chain issues is further delaying the delivery at some planes. Among other things causing headaches is securing a reliable supply of foam insulation tape that Boeing uses as a fire suppressant. Assembly line workers cannot add the final sidewall panels that line the interior of the cargo bay without supplies of the tape.

The newspaper reports there are also problems with seat deliveries at the MAX assembly plant in Renton. As Gates notes, it's just one seemingly random supply chain issue that's holding up the assembly of the planes. As of February 28, Boeing has undelivered orders for 4,137 MAXs. Currently, Boeing is building 27 MAXs a month. Without taking any further orders, at this rate, it will take Boeing 153 months (or nearly 13 years) to clear the backlog.

Boeing's supply chain problems could worsen

Boeing's problem is that there is no relief on the supply chain horizon. Instead, supply chain problems look like getting worse. Boeing draws on suppliers from around the world. When supply chains work seamlessly, the manufacturer's lean towards cost-efficient just-in-time inventory delivery works well. But when supply chains get disrupted, as is the case now, Boeing faces a challenge. Boeing says the timing of their jet deliveries depends upon customer requirements, logistics, and their own processes.

Speaking at the recent Singapore Air Show, Gary Lowe, Chief Executive of ThyssenKrupp Aerospace North America, said he expected ongoing supply chain problems at Boeing and Airbus.

"Wherever I look in the supply chain, I see problems," he said. "I think it's going to be a lot more lumpy and problematic than people realize."

Boeing's order book updated

Meanwhile, the Chicago-based plane builder has also updated its order and deliveries report, with data now running through to February 28. Boeing delivered 22 planes in February, including 20 737 MAXs, a 777 freighter bound for DHL, and a 747-8 freighter heading to UPS.

Also in February, Boeing took orders for 37 planes, including 32 MAXs and five 777 freighters. Eighteen of those 32 MAXs are going to Air Lease Corp while Western Global Airlines purchased two of the 777 freighters. Boeing has not yet confirmed the identity of other MAX and 777 buyers last month.