Key Highlights

● GE Aerospace (GE) closed at $318.24 on Monday, down from $327.09, as the S&P 500 lost 59.72 points.

● The FAA will not certify Boeing's 737 MAX 10 until it assesses a software issue, and GE supplied that software.

● FAA Administrator Bryan Bedford said the agency will delay the aircraft until it is satisfied there is no issue.

● Boeing closed at $184.39, down from $198.07, one of the biggest decliners in the Dow, while industrials sold off broadly.

GE Aerospace (NYSE:GE), the jet-engine and aviation-systems giant, fell on Monday, September 28. GE Aerospace closed at $318.24, down from $327.09 on Friday. The drop came as the S&P 500, the benchmark index of 500 large US companies, slid 59.72 points to 7,683.69.

Collateral Damage from Boeing's Setback

The main pressure point came from Boeing (NYSE:BA). The Federal Aviation Administration said it would not certify the 737 MAX 10 until it assesses a newly flagged software issue, and GE Aerospace supplied that software, according to reports. No separate GE announcement was found to explain Monday's move.

What the FAA Flagged

The issue involves automated flight guidance, which can be unavailable in some landing and go-around scenarios, according to the FAA. A go-around is when pilots abort a landing and climb away to try again. The FAA said the software "can increase pilot workload when doing a go-around."

FAA Administrator Bryan Bedford was blunt: "We will be delaying the 10 until we're satisfied that we don't have an issue here." A Boeing spokesperson said: "We continue to follow the lead of the FAA as we work through the certification process."

Boeing Took the Bigger Hit

Boeing bore the brunt of the news. Boeing closed at $184.39, down from $198.07 on Friday, a fall of about 6.9% that made it one of the biggest decliners in the Dow.

The 737 MAX 10 is the largest version of Boeing's best-selling narrow-body jet family, and airlines have been waiting for it for years. Every certification delay pushes back deliveries, and for suppliers, the pace of Boeing's production affects their own sales of engines, parts and systems. That link helps explain why GE felt the pain, even though the regulatory spotlight fell on Boeing.

Industrials Under Pressure

The wider market added to the strain. Industrials was one of the four S&P 500 sectors that fell hardest on Monday, according to market data, alongside communication services, consumer discretionary and financials. The Dow lost 347.11 points to 51,481.51, with Boeing the biggest drag.

Bond yields surged as well. The 10-year Treasury Yield rose to its highest level since 2007 after President Trump rejected Iran's plan to reopen the Strait of Hormuz and oil prices climbed. Higher oil prices matter directly for aviation, since jet fuel is one of airlines' largest costs, and a squeeze on airline finances can ripple back through to aircraft and engine makers.

The FAA's Verdict Will Set the Tone

The most important thing for GE Aerospace shareholders is any update from the FAA on its assessment of the software issue. A quick fix could ease concerns about MAX 10 timing, while a lengthy review could keep pressure on Boeing and its suppliers. Any comment from GE on the matter will also be watched closely.

The macro calendar will matter too, from JOLTS and consumer confidence on Tuesday to PCE Inflation on Wednesday, the ISM Manufacturing survey on Thursday and the jobs report on Friday. The ISM survey offers a read on factory activity that can move industrial stocks, and any hot inflation data could push yields and pressure the sector further.