Flight Safety Information - August 13, 2026 No. 158 In This Issue : Incident: Delta B739 at Pensacola on Aug 9th 2026, flap detached on departure : Incident: Indigo A21N at Chennai on Aug 11th 2026, engine inoperative : Boeing 777-36NER - Landing Gear Smoking and Caught Fire on Landing ((China) : Air safety authorities investigating third Sydney Airport runway take-off incident : What’s that smell? Aircraft fume events back in spotlight ahead of London conference : South Korean airport becomes busiest in world for global traffic amid Iran war : Airbus Delivers 67 New Aircraft In July, Remains Below Monthly Average To Meet Annual Target : Researchers Use a Physical Device to Take Over Electronics in a Boeing 737 : Airlines Will Face Jet Fuel Issues For Months To Come, Energy Expert Says : How The World's Most Powerful Jet Engine Handles 2,400-Degree Temperatures : American Airlines shakes up leadership as CEO faces pressure to close profit gap : Explaining DO-178C: The safety standard for software in aviation : Calendar of Events Incident: Delta B739 at Pensacola on Aug 9th 2026, flap detached on departure A Delta Airlines Boeing 737-900, registration N895DN performing flight DL-3067 from Pensacola,FL to Atlanta,GA (USA), departed Pensacola's runway 35, climbed to FL250 and landed on Atlanta's runway 09R about 45 minutes later. However, the FAA reported: "AIRCRAFT TRAILING EDGE FLAP DETACHED FROM THE WING, PENSACOLA, FL." The aircraft remained on the ground in Atlanta for 23.5 hours before returning to service. https://avherald.com/h?article=53d6faec&opt=0 Incident: Indigo A21N at Chennai on Aug 11th 2026, engine inoperative An Indigo Airbus A321-200N, registration VT-IMI performing flight 6E-723 from Kolkata to Chennai (India) with 224 people on board, was descending through about 6000 feet towards Chennai about 10 minutes prior to estimated landing when the crew declared emergency reported the left hand engine (LEAP) was inoperative. The aircraft landed safely on runway 25 about 9 minutes later. The airline reported a "technical snag". The airport reported the aircraft declared emergency 9 minutes prior to landing reporting the left hand engine was inoperative. The aircraft is still on the ground in Chennai about 21 hours after landing. https://avherald.com/h?article=53d6f3e2&opt=0 Boeing 777-36NER - Landing Gear Smoking and Caught Fire on Landing ((China) Date: Tuesday 11 August 2026 Time: 16:06 Type: Boeing 777-36NER Owner/operator: EgyptAir Registration: SU-GDR MSN: 38291/926 Year of manufacture: 2011 Engine model: General Electric GE90-115B Fatalities: Fatalities: 0 / Occupants: Other fatalities: 0 Aircraft damage: None Location: Guangzhou Baiyun International Airport (CAN/ZGGG) - China Phase: Taxi Nature: Passenger - Scheduled Departure airport: Cairo International Airport (CAI/HECA) Destination airport: Guangzhou Baiyun International Airport (CAN/ZGGG) Confidence Rating: Information is only available from news, social media or unofficial sources Narrative: A EgyptAir Boeing 777-36NER SU-GDR, performing flight MS958 from Cairo, (Egypt) to Guangzhou, (China). The left main landing gear tires were smoking and catching fire after landing at Guangzhou Airport at 15:31. Emergency vehicles arriving to handle the situation, and there were no reports of injuries. https://www.aviation-safety.net/wikibase/575901 Air safety authorities investigating third Sydney Airport runway take-off incident An air traffic control mix-up has contributed to a third runway take-off incident at Sydney Airport in as many weeks. In short: Safety authorities are investigating a third runway incident at Sydney Airport that involved a Qantas flight crossing the path of a departing Virgin Australia aircraft. The incident followed a Jetstar flight slamming on its brakes during take-off to avoid colliding with a Qatar Airways plane being towed on the tarmac. What's next? The ATSB said it would conduct interviews with Virgin and Qantas crew involved and review recorded flight data. Safety authorities are investigating a third runway incident at Sydney Airport involving a Qantas flight crossing the path of a departing Virgin Australia aircraft. The Australian Transport Safety Bureau (ATSB) said on Wednesday that the incident on Sunday involved Virgin Australia Flight VA555 destined for Perth and Qantas Flight QF728 flying to Ayers Rock Airport. "At around 10am local time, air traffic control (ATC) cleared the Virgin Australia 737 for a full-length take-off on runway 34L," an ATSB statement said. "As the crew applied thrust for take-off, they observed the Qantas 737 begin to cross the runway ahead of them from taxiway Lima. "The Qantas crew reported having received a clearance from ATC to cross the runway. "The Virgin Australia crew reduced thrust and the aircraft came to a stop on the runway." The ATSB said air traffic controllers cancelled VA555's take-off clearance at the same time its crew noticed the Qantas aircraft ahead. "Once the Qantas 737 was clear of the runway, the Virgin Australia 737 was re-cleared by ATC to commence take-off," the ATSB said. It is understood the Qantas plane began to cross the runway about 1,200 metres ahead of where the Virgin Australia flight had started to take off, before its clearance was cancelled four seconds later. The ATSB said it would conduct interviews with the crew involved and review recorded flight data as part of its investigation. Air Services Australia said the two aircraft were never in close proximity and it was working with the Australian Transport Safety Bureau to investigate the incident. Aviation boss summoned, airport workers stood down after Sydney near-miss Jetstar flight almost colliding with another plane on the tarmac Australian Transport Safety Bureau's Chief Commissioner Angus Mitchell says pilots who avoided a near miss at Sydney Airport on Sunday morning "prevented what could have been far more serious". Spokespeople for Qantas and Virgin Australia told the ABC the airlines would support the ATSB investigation into the incident. In another incident earlier on Sunday, Jetstar Flight JQ402 was preparing to take off when it was forced to slam on the brakes to avoid colliding with a Qatar Airways 777 that was being towed along the tarmac. ATSB chief commissioner Angus Mitchell said on Monday that the Jetstar incident "could have been far more serious" if the pilots involved had not been quick-thinking. He said those sorts of runway incidents "shouldn't happen". "We do have an aviation sector that is the envy of the world. That's not to say that with incidents like this, we don't take them seriously to improve," he said. "But aircraft movements, whether it be in a busy airport or in the skies, are incredibly well coordinated here in Australia." Two airport workers were stood down temporarily following the near collision, which left a Jetstar crew member injured yesterday. Two weeks earlier, on July 27, a QantasLink flight and a Qantas plane were involved in a near-miss on the tarmac. Recent workforce shortages and rostering issues have contributed to delays at Sydney Airport. https://www.abc.net.au/news/2026-08-13/third-sydney-airport-runway-take-off-incident-investigated/107035400 What’s that smell? Aircraft fume events back in spotlight ahead of London conference Smoke, strange odours and suspected contaminated air continue to disrupt flights worldwide. This September, experts will gather in London to examine what causes fume events, what they mean for safety and what aviation can do about them. A woman with shoulder-length blonde hair and blue eyes smiles warmly at the camera, wearing a light-colored blazer against a teal background in what appears to be a professional headshot. In the space of just a few days, passengers have been evacuated from a Boeing 757 after smoke and fumes were reported in the cockpit, while a JetBlue Airbus A320 diverted to Jacksonville after its pilots encountered an acrid smell that irritated their eyes and lungs. Look for these types of incidents, and they are surprisingly easy to find. A major Wall Street Journal investigation into aircraft fume events found 108 reported incidents per million departures among major US airlines in 2024, equivalent to around two a day. But internal airline industry data reviewed by the Journal estimated the true rate could be closer to 800 events per million flights, or around 22 every day in the US alone. It is an issue that has been debated for decades, and one that will come under renewed scrutiny when the 2026 Aircraft Cabin Air International Conference brings aviation, medical, regulatory and scientific experts together in London this September. What is an aircraft fume event? The UK Civil Aviation Authority describes a fume event as involving an unusual odour, mist or smoke on an aircraft. Not every strange smell in a cabin is evidence of contaminated air: sources can range from overheated electrical equipment to cleaning products or something burning in a galley oven. But on most commercial aircraft, outside air used to ventilate and pressurise the cabin is taken from the compression stages of the engines through the bleed-air system. If oil or other fluids contaminate that air supply, fumes can potentially reach the cockpit or cabin. The smell can be difficult to describe. Engine-oil-related events have been likened to dirty or wet socks, while others are described as acrid, chemical or oily. The debate is not simply about how frequently this happens, but how events are detected, reported and investigated, what they mean for flight safety and whether more can be done to prevent them. Scientific work is continuing too. A recently published iScience study examining 42 organophosphates and commercial mixtures found widespread endocrine-disrupting activity, with aryl and triaryl phosphates showing some of the strongest effects. The researchers specifically identify aviation lubricants as a source of exposure to certain organophosphates. Aircraft Cabin Air Conference returns to London The 2026 Aircraft Cabin Air International Conference takes place at Imperial College London on September 22 and 23, bringing together more than 30 speakers and contributors from aviation, science, medicine, regulation, unions and industry. The conference is designed to examine not only the contaminated-air debate itself, but what aviation can practically do about it. Its objectives include mapping the flight-safety implications of contaminated air through case studies and accident investigations; examining the latest medical and scientific research; considering legal, regulatory and workers’ compensation issues; and reviewing the positions and guidance of organisations including ICAO, IATA, EASA, the FAA, IFALPA, ITF and GCAQE. Crucially, the program will also look at potential solutions, including less hazardous engine oils, bleed-air filtration, contaminated-air warning sensors and air-cleaning technologies, as well as developments in reporting and investigation. Among the confirmed subjects are the EASA CAQ III cabin-air research program, the implications of cabin-air provisions in the FAA Reauthorization Act of 2024 and the work of the UK’s All-Party Parliamentary Group (APPG) on Cabin Air Quality. Alongside scientists and medical doctors, industry speakers confirmed so far include specialists from Portuguese airline TAP, Collins Aerospace, Pall Aerospace, PTI Technologies, TSI, Aeroparts, CTT Systems and BASF. Worker speakers include Association of Flight Attendants-CWA International President Sara Nelson and the International Transport Workers’ Federation Civil Aviation Secretary Bilal Malkawi. The Aircraft Cabin Air International Conference takes place at Imperial College London on September 22–23. Early-bird registration is currently available at £525 plus tax, with booking available through the conference website. Have you experienced a fume event? The British APPG on Cabin Air Quality is also seeking evidence from people with first-hand experience of an aircraft fume event as part of its ongoing inquiry. Pilots, cabin crew, passengers and others who have personally experienced an event are being encouraged to complete the APPG’s survey, with responses helping parliamentarians build a clearer picture of what happens when these incidents occur and how those affected experience the aftermath. For an issue aviation has been debating for decades, there is no shortage of new evidence, new incidents or new questions. September’s conference will bring many of the people trying to answer them into the same room. https://aerospaceglobalnews.com/news/aircraft-fume-events-cabin-air-conference-2026/ South Korean airport becomes busiest in world for global traffic amid Iran war Incheon airport had 38.39m international passengers in first half of 2026, as traffic diverted from Middle East hubs South Korea’s Incheon airport has become the world’s busiest airport for international passengers, in part owing to disruption in the Middle East caused by the Iran war. The airport, South Korea’s main gateway, about 30 miles (48km) west of Seoul, handled 38.39 million international passengers in the first half of 2026, according to preliminary figures compiled by the Airports Council International (ACI), the global trade body for airports. Heathrow in the UK was second, with 37.79 million, followed by Changi airport in Singapore with 34.53 million. It is the first time Incheon has topped the international passenger rankings since opening in 2001. The airport was 10th in the world in 2002, rising to fifth in 2018 and third in 2024 and 2025. Part of the increase was attributed to disruption caused by the US-Iran conflict, which weakened the role of Middle Eastern hubs such as Dubai and diverted some transfer traffic to alternative routes through east Asia, Incheon International Airport Corporation (IIAC) was quoted as saying by the Yonhap news agency. Incheon’s international passenger traffic was up 6.3% year on year overall, with rising numbers of foreign visitors also contributing to the increase. Foreigners accounted for 39.3% of Incheon’s passengers in the first half of the year, up from 35.2% for the whole of 2025. The proportion reached a record 44.4% in the second quarter, with IIAC attributing the increase largely to growing numbers of visitors from China and Japan, according to local media. Heathrow, in west London, recorded 40 million passengers in total in the first half of the year, including both domestic and international travellers, its busiest first half on record. Passenger traffic to Asia-Pacific rose 7.9%, while capacity to the Middle East reportedly fell 16.5% owing to the regional conflict. Earlier this week Istanbul overtook Heathrow as Europe’s busiest airport by total passenger numbers. Figures published on Tuesday showed 7.9 million passengers passed through Heathrow’s terminals in July, compared with Istanbul’s 8.15 million. Incheon has also expanded its role as an international hub. It serves 101 airlines flying to 183 cities, including 158 international passenger destinations. A four-phase expansion completed in late 2024 increased the airport’s annual capacity to 106 million passengers. Kim Beom-ho, the acting president of IIAC, said the ranking reflected “the support of the government, the public’s encouragement and the hard work of everyone stationed at the airport”. South Korea also lays claim to the world’s busiest air route. The domestic corridor between Gimpo airport and Jeju island had 14.4 million seats scheduled in 2025, according to the aviation data provider OAG, more than any other route in the world. https://www.theguardian.com/world/2026/aug/13/south-korea-incheon-airport-iran-war-middle-east Airbus Delivers 67 New Aircraft In July, Remains Below Monthly Average To Meet Annual Target European aircraft manufacturer Airbus is still behind its target to deliver an average of 90 aircraft a month to meet its ambitious target of 870 deliveries this year. This comes after Airbus delivered just 67 airframes in July. As the manufacturer released its earnings results last week, Airbus remained confident it could reach the full-year target, while still battling Pratt & Whitney engine supply chain delays. So far this year, Airbus has achieved a total of 418 jet deliveries, and July saw 67 aircraft delivered (the same number as in July 2025). While the aircraft manufacturer has a target of 870 aircraft, Airbus Chief Executive Officer Guillaume Faury suggested that internally Airbus is pushing for 900 deliveries. Airbus Deliveries: 67 Aircraft Handed Over In July In a report by Reuters, Airbus faces ongoing delays with engine parts and accessibility from Pratt & Whitney; Airbus remains steadfast on achieving its ambitious goal of 870 aircraft before the year-end. While just 67 aircraft were delivered in July, the aircraft manufacturer seems adamant that it will achieve its goal before the end of the year. Airbus faced a subdued Farnborough Airshow, seeing the aircraft manufacturer record just a total of 204 airplane orders last month, which sees the total order book rise to 1,024, or 1,090 when including adjustments. This takes into consideration the 15 A330neo that were canceled by Malaysian low-cost carrier AirAsia X, and its pivot to order a total of 150 A220s made last month. Delivery fluctuations and supply-chain constraints have forced a persistent bottleneck at Airbus, delaying airframes for final engine installation and delivery. A headline order from SMBC Aviation, an Irish aircraft leasing company, saw a total of 100 A320neo family of aircraft added to the books for Airbus, making up half of all aircraft orders at the UK-based airshow. Other commitments included six additional A350-1000 for Riyadh Air, taking the total order up to 31 for the new Saudi airline startup. Other deals included an order for two A320neo and two A321neo for Tajikistan carrier Shohin Airlines, and Philippine Airlines plans to acquire six A350-1000 airplanes, which will revolutionize the airline's long-haul network. Boeing narrowly beat Airbus at Farnborough when it came to overall orders. Boeing secured a total of 173 aircraft at the UK airshow, slightly ahead of Airbus, which secured a total of 154 jets. This saw a combined total of 327 aircraft across both manufacturers, well below the predicted forecast that around 800 airplanes were to be ordered at the show. Airbus' ability to maintain a sustainable production ramp-up will be crucial in achieving its 870-aircraft delivery target for the full year. July Breakdown Of Aircraft Deliveries Airbus' 67 commercial aircraft deliveries in July were to 39 different customers. Of these 67 planes, 37 were A321neo, 18 A320neo, six A220-300, four A350-900 and two A350-1000. In July, no A330neo deliveries took place. This was a drop of 22 aircraft compared with the June number of 89. In the final five months of the year, the European aircraft manufacturer needs to deliver a total of 452 handovers, an average of 90 per month, to meet the midpoint of its annual target. Boeing is expected to release its latest delivery data next week, which will provide an up-to-date comparison between the two plane makers. While Airbus remains behind track to meet its ambitious goal of between 870 and 900 aircraft, it remains committed to increasing delivery output in the final few months of the year, despite being at the mercy of ongoing supply chain delays and engine deliveries, paired with widespread industrial challenges which have limited the flow of some raw materials and hardware, while also working through quality issues with forward fuselage panels from specific suppliers. https://simpleflying.com/airbus-delivers-67-new-aircraft-july-below-monthly-average-meet-annual-target/ Researchers Use a Physical Device to Take Over Electronics in a Boeing 737 Computer science researchers developed and tested a device that, if plugged into a hardwired communications channel connecting two key flight computers, can take over communications between these computers. The researchers designed, built and programmed a small hardware device, which acts as a third-party entity that takes over two key computers on a 737 aircraft. Newswise — Physical access to an aircraft has not typically been considered a cybersecurity risk – but it should be, according to a team of computer scientists at the University of California San Diego. In a paper presented Aug. 13 at the USENIX Security Symposium in Baltimore, Md, former UC San Diego PhD student Sam Crow showed that physical access to an aircraft – even for a brief period of time – would allow an attacker equipped with a custom-made hardware device to take over the communications between two key onboard computers. The device needs to be plugged into a port inside the plane’s belly – an action that the researchers estimate would take under 60 seconds. This would require access to the aircraft either when parked at a gate or when in an airport hangar during regular maintenance. Access to these areas is controlled carefully but not always successfully, the computer scientists note in the new paper. The researchers successfully demonstrated the attack on a testbed made of actual Boeing 737 airplane parts and airplane software. The proof-of-concept attack allowed researchers to change the plane’s flight path and change data that could make takeoff conditions unsafe. But they are careful to note that the attack requires someone to do significant planning and engineering work ahead of time. The research team communicated closely with Boeing, disclosed the vulnerability in 2020, and further tested and validated their findings in Boeing’s own lab. Of note, the Boeing 737 is one of the most used aircraft in commercial aviation, with 8000 in service today. It makes up about 25% of Delta’s existing fleet, 38% of American’s, 53% of United’s and all of Southwest Airlines’ fleet. However, while the team’s implementation is designed for the Boeing 737 specifically, the researchers believe their findings are relevant for the aviation industry more generally. “Our goal with this research is to alert the aviation community to this class of risks, so they may be appropriately mitigated well before they become dangerous. All of the authors of this paper routinely travel on Boeing 737 aircraft and expect to continue doing so,” said UC San Diego computer scientist and cybersecurity expert Aaron Schulman, one of the senior authors of the work. The research team, led by Schulman and Stefan Savage, both professors in the UC San Diego Department of Computer Science and Engineering, presented their peer-reviewed work describing the vulnerability and attack Aug. 13 at the USENIX Security Symposium. How does the attack work? The researchers discovered an unused maintenance port located in the plane’s Electronics and Equipment bay, which houses key electronic systems. This bay is located just under the plane’s nose, can be reached from the ground, and isn’t locked. This maintenance port provides access to the data transmitted between two critical on-board computers. One computer is the flight management computer, which controls the plane’s flight path as well as approach path before landing and also supplies critical information at takeoff. The other is the computer that displays this flight path information, along with other critical flight data for the pilots in the cockpit. Information and instructions to and from these two computers is ferried by hard-wired communication systems known as buses – in this case, two ARINC 429 buses, which were invented in 1977. Buses, like the ARINC 429, convey data via current flowing through two wires and a set of resistors. Because the system is decades old, it does not have data security features, such as message authentication. The researchers designed, built and programmed a small hardware device, which acts as a third-party entity that takes over these buses. It does so by driving more current so it can override any legitimate transmissions with its own. This approach allows the device to covertly transmit new instructions to the flight management computer while suppressing indications that changes have been made. Using their proof-of-concept demonstration, the researchers showed that their implant could re-route a plane in flight or modify data about weight, balance and temperature, which could lead to an unsafe takeoff. While pilots could override such changes, it would require that they detect that a compromise had occurred. “We believe we have made a strong case that time-limited physical access (e.g., 60 seconds) represents a realistic goal for a motivated attacker and that the consequences of even such short access can be significant (and hence worthy of attention),” the researchers write. Design and Implementation of a Physical Implant Attack on the Boeing 737 https://www.newswise.com/articles/researchers-use-a-physical-device-to-take-over-electronics-in-a-boeing-737 Airlines Will Face Jet Fuel Issues For Months To Come, Energy Expert Says WASHINGTON—The jet fuel crisis is likely to get worse before it improves, and some LCCs may not survive a prolonged period of higher costs, an energy and oil expert says. Houston-based Chris Russo, associate director for energy in North America at Publicis Sapient, told the Aviation Week Window Seat podcast that even if Iran war ended tomorrow and the Strait of Hormuz fully reopened, two factors would ensure jet fuel prices remain high for months to come. “The current-state problem is that refineries that take the crude and turn it into products that we use like gasoline, diesel and jet fuel are at capacity. They cannot produce any more of the refined product. The global refinery output has actually decreased. So even if we’re flush with crude, there’s only so much that they can produce right now and the demand for it is still so high that we are in a problem today with those prices,” Russo said. “The longer-tail problem that we have not properly equated for yet is that there is going to be a crude inventory shortage.” China and the U.S. have relied on their strategic oil reserves since the Iran war started nearly six months ago, Russo said, pointing to a statement by Shell CEO Wael Sawan that the world was facing a nearly one-billion-barrel supply shortage. “This hasn’t been factored into the prices of crude, so that will come back to bite because it will jack up prices again in the future and cause problems downstream for things like jet fuel,” Russo said. “This is going to be a challenge for airlines for a long while.” Russo said airlines should change their thinking about fuel purchases. “Most airlines look at fuel as just a cost of doing business. It’s a line item for them to pay and not necessarily get ahead of,” he said. “But airlines need to start taking a bit more of a longer-term view on how they want to procure fuel and how to manage the fuel and the procurement process as a whole.” Beyond reactive steps, like cutting routes or frequencies, or even fuel hedging, Russo said airlines should closely examine the contracts they have with suppliers to guarantee some amount of fuel over the next 12 or 24 months. “In those contracts, there are always terms and conditions around optionality. There are all these little things that can get inserted that often the airlines forget about,” he said. “And then when things happen in the market that change, you may have different levers within those contracts that could potentially help you acquire more at a better price or otherwise move product. Maybe you don’t want to pick it up in your Los Angeles market or your Amsterdam market, but in another location that’s important.” Russo said working those options could save an airline one to four cents per barrel, a meaningful saving when so many barrels are being bought. And while demand for air travel has remained strong worldwide, even at higher fares, Russo does not believe that is sustainable. “I really believe demand is going to go down at some point,” he said. “If these fuel prices keep going up, eventually it’s going to hit some threshold where passengers will refuse to pay those prices. So, do you get ahead of it by trying to hedge in anticipation of some drop in demand?” Russo also believes that some LCCs will not be able to survive a prolonged period of higher jet fuel costs. “No matter if you’re in the U.S. or in Europe or in Asia-Pacific, there is something to be said about the legacy carriers being a little bit excited about high fuel prices because of what that can do to the market in eliminating the low-cost carriers, such as Spirit Airlines. You are talking about eliminating your competition.” he said. “That’s actually a good thing. So, there’s the silver lining for your legacy carriers. I’m not saying that they wish ill, but let’s be real. When it comes to business sense, the less competition, the better.” https://aviationweek.com/air-transport/airlines-lessors/airlines-will-face-jet-fuel-issues-months-come-energy-expert-says How The World's Most Powerful Jet Engine Handles 2,400-Degree Temperatures When Boeing launched the 777X program in November 2013, the aircraft was intended to become the most efficient twin-engine widebody ever built. Powered exclusively by the GE9X, the jet promised a 10% reduction in fuel burn compared to the Boeing 777-300ER while carrying up to 426 passengers in a two-class layout and flying more than 7,200 nautical miles (13,334 km). But more than a decade later, the aircraft remains uncertified, making the 777X one of the longest-delayed commercial aviation programs in Boeing’s modern history. Behind the aircraft is one of its most technologically ambitious components: an engine designed to operate under extraordinary temperatures and pressures. The GE9X's pursuit of greater thermal efficiency means components inside the engine must operate in an environment where temperatures can exceed 2,400 degrees Fahrenheit (1,315°C). The GE9X was engineered around extreme thermal efficiency, using advanced ceramic matrix composites, fourth-generation carbon-fiber fan blades, and a 134-inch (3.4-meter) fan, the largest ever fitted to a commercial aircraft. Its core temperatures approach the levels at which conventional nickel-based alloys begin to lose structural strength, forcing engineers to rely on complex cooling systems and thermal coatings to maintain reliability. A recent durability issue involving an internal seal provides one example of just how demanding that operating environment can be. The engine manufacturer has said the midseal issue is not impacting 777X certification or entry into service. The GE9X Was Built To Push Commercial Engine Limits The GE9X was developed as the successor to the GE90, an engine family that powered the Boeing 777 for nearly three decades and accumulated more than 100 million flight hours. To justify replacing such a successful platform, GE Aerospace needed dramatic efficiency gains rather than incremental improvements. The engine holds the title as the most powerful commercial aircraft engine ever developed, with a certified thrust rating of 110,000 pounds-force (490 kN). During test campaigns, the engine surpassed that figure dramatically, reaching 134,300 pounds-force (597 kN), a performance strong enough to earn a Guinness World Record. The bypass ratio increased to roughly 10:1, compared to about 8.5:1 on the GE90, allowing the engine to move significantly more air around the core instead of through it. A major contributor to the engine’s efficiency was its high-pressure compressor, which achieved a pressure ratio near 27:1, among the highest in commercial aviation. Combined with an overall pressure ratio approaching 60:1, the GE9X extracted more energy from combustion than earlier widebody engines. However, achieving those figures required running the core at far higher temperatures and pressures, dramatically increasing stress on internal components. Even minor variations in airflow or cooling efficiency could influence component life inside the turbine section. The engine also introduced extensive use of ceramic matrix composite materials. These components are roughly one-third the weight of traditional aerospace alloys and can tolerate temperatures several hundred degrees hotter than conventional metals. GE incorporated CMCs into combustor liners, turbine shrouds, and hot-section structures to reduce cooling requirements and improve efficiency. Yet the same technologies that reduced weight and improved thermal performance also make long-term durability validation particularly important in such an extreme operating environment. Extreme Temperatures Created Extraordinary Engineering Challenges The GE9X’s thermal environment is fundamentally different from earlier commercial turbofans. During operation, temperatures within the combustor and high-pressure turbine sections can exceed 2,400 degrees Fahrenheit (1,315 °C), surpassing the melting point of many structural metals used in aerospace manufacturing. To prevent catastrophic material degradation, the engine depends on a network of microscopic cooling passages that route compressed air through turbine blades and surrounding structures. These systems create thin insulating layers of cooler air between engine hardware and combustion gases. One durability issue identified in the GE9X involved a seal system operating within this demanding engine environment. Internal seals perform a critical role inside high-bypass turbofans because they regulate pressure distribution and maintain precise airflow paths through the engine core. If seals wear unevenly or deform under thermal stress, airflow balance changes throughout the turbine section. That can reduce efficiency, increase vibration, accelerate fatigue, and alter thermal loading across adjacent components. Boeing Already Built 20+ 777Xs — But They Can’t Fly Yet Modern engines operate with far tighter tolerances than earlier generations, leaving little room for unexpected expansion or wear. On older engines, designers often incorporated larger mechanical margins that sacrificed some efficiency for long-term robustness. The GE9X was optimized far more aggressively because airlines demanded lower operating costs and reduced emissions. That makes understanding and managing wear particularly important as the engine accumulates operating cycles. How Much Does A Boeing 777X Cost? A few hundred million must be spared to acquire a brand-new Boeing 777X. The seal-related durability concern surfacedagainst the backdrop of the wider 777X flight-test program . The 777X first flew in January 2020, but FAAoversight intensified after the Boeing 737 MAX crisis led regulators to adopt far stricter certification procedures across all Boeing programs. Additional delays followed after a 2019 decompression event during structural testing forced Boeing to redesign portions of the aircraft’s fuselage and inspection procedures. By early 2026, Boeing had accumulated thousands of flight-test hours across multiple aircraft as the wider 777X certification campaign continued. In parallel, work continued on the GE9X durability issue as engineers addressed the demands of maintaining reliability and acceptable maintenance intervals in such an extreme operating environment. Industry analysts viewed the timing as particularly damaging because airlines had already adjusted fleet strategies around repeated 777X delays. Emirates alone ordered more than 200 aircraft from the 777X family, making it the program’s largest customer. Several carriers extended older widebody fleets or retained Airbus A380 aircraft longer than planned while waiting for the 777-9 to enter service. The wider delays have carried financial implications not only for Boeing and its suppliers but also for airlines that built long-term network planning around the aircraft's arrival Fixing The Seal Required Far More Than A Replacement Part Although the issue involved a relatively small internal component, resolving it proved exceptionally complicated because of how interconnected modern turbofan systems have become. Changes to seal geometry can alter airflow behavior across multiple turbine stages, influencing thermal expansion rates, vibration harmonics, and cooling efficiency throughout the engine core. Engineers, therefore, needed to ensure that any redesign corrected the original wear issue without unintentionally creating new stress concentrations elsewhere in the engine. GE Aerospace reportedly implemented revised tooling, updated inspection procedures, and modified production processes as part of the corrective effort. That required validating not only the redesigned hardware itself, but also the manufacturing consistency of the updated configuration. In high-pressure turbine environments, microscopic variations in surface finish or dimensional tolerances can significantly influence durability outcomes over thousands of thermal cycles. The engine manufacturer also had to demonstrate that the revised design would maintain acceptable maintenance intervals over long-term airline operations. Commercial carriers evaluate engines largely on lifecycle economics, including time on wing, overhaul frequency, and unscheduled maintenance risk. Even if an issue poses no immediate safety hazard, premature wear can erase fuel-efficiency advantages by increasing maintenance costs and reducing aircraft availability. Why FAA Pilots Flying The Boeing 777X For The 1st Time Changes Everything FAA pilots independently review the aircraft as one integrated system. The difficulties surrounding the GE9X highlight a wider trend affecting the entire aerospace industry. Modern commercial engines are approaching thermodynamic and material limits that were once considered impractical for large-scale airline operations. Because aerodynamic improvements now produce smaller gains than in previous decades, manufacturers increasingly rely on hotter cores, higher pressure ratios, lighter materials, and tighter tolerances to improve fuel efficiency. This strategy has delivered major environmental and economic benefits. According to GE, the 777-9 is expected to reduce fuel consumption and carbon emissions by approximately 20% compared to the aircraft it replaces. However, those gains come at the cost of greater engineering complexity. Modern engines contain more advanced materials, more sensitive thermal systems, and narrower performance margins than earlier generations, making development programs more vulnerable to unexpected durability issues. The GE9X represents more than an extraordinarily powerful commercial engine. It illustrates how next-generation aerospace engineering increasingly depends on mastering long-term survivability. In previous decades, performance breakthroughs often depended on making engines larger or more powerful. Today, the decisive challenge is ensuring highly optimized engines can endure years of airline service while operating close to the edge of material science itself. https://simpleflying.com/ge9x-jet-handles-temperature-boeing-777x/ American Airlines shakes up leadership as CEO faces pressure to close profit gap CHICAGO, Aug 12 (Reuters) - American Airlines (AAL.O), opens new tab is reorganizing senior management, broadening oversight across its commercial and operations teams and adding a former Spirit ‌Airlines executive to run technical operations, as CEO Robert Isom faces pressure to close the carrier's profit gap with rivals. In a staff memo seen by Reuters, Isom acknowledged a "meaningful gap" between American's current performance and where he said the airline should be. He said the moves were the "first step in a series of actions" aimed at strengthening the team, improving alignment and accelerating execution. The company's profit gap with ⁠Delta Air Lines (DAL.N), opens new tab and United Airlines (UAL.O), opens new tab was already wide before the recent fuel shock that followed the U.S.-Israeli attacks on Iran that kicked off a war that has caused energy prices to surge. Former Spirit Airlines COO John Bendoraitis will join American to lead technical operations, one of a number of moves to try to boost performance. Chief Commercial Officer Nat Pieper will add marketing and branding to his duties, Chief Customer Officer Heather Garboden will take on reservations and service recovery, and JC Gulbranson will add airports and planning. Chief Communications Officer Ron DeFeo is stepping down, according to the memo. Caroline Clayton will oversee communications and Steve Neuman ‌government affairs. Garboden, ⁠Gulbranson, Clayton and Neuman will join American's senior leadership team. American expects roughly break-even results in 2026, as higher jet fuel prices ate up gains from stronger revenue. Delta and United expect solid profits. The heat on Isom has already been building. Flight attendants earlier this year called for a leadership change, while its pilot union has questioned whether the current management team ⁠can close the earnings gap. Pilots' union head Nick Silva recently contrasted American's breakeven outlook with profits at rivals, arguing that "rising fuel costs are not holding our competitors back from innovation and profitability." This is a vital time of year In a memo to pilots last week, Silva said ⁠the union had sought a meeting with American's board to discuss concerns about the company's future but was "rebuffed." It has since held discussions with analysts, investors and other stakeholders, he said. "The consensus is clear: Something must ⁠change. The only question is 'When?'" Silva wrote. Isom made clear he is not changing course, saying American has "the right strategy and the right team to deliver it," as it focuses on expanding its global network, growing premium revenue and strengthening its AAdvantage loyalty program. https://www.reuters.com/business/american-airlines-shakes-up-leadership-ceo-faces-pressure-close-profit-gap-2026-08-12/ Explaining DO-178C: The safety standard for software in aviation DO-178C, officially titled Software Considerations in Airborne Systems and Equipment Certification, serves as the foundational standard for aerospace safety. It is the primary standard used by certification authorities like the Federal Aviation Administration (FAA), which regulates civil aviation in the United States, and European Union Aviation Safety Agency (EASA) which does the same in the European Union. The standard establishes processes that minimise the risk that software failures could compromise aircraft safety. In essence: it mandates rigorous demonstration that the software executes its intended functions precisely, and solely those functions. So, what are its operational mechanics, its scope of coverage, and the compliance considerations essential for manufacturers? Designed to be traceable While DO-178C is the standard used by certification authorities to approve software-based aerospace systems, Software Assurance Levels (SAL) are assigned to software components based on the safety assessment process and hazard analysis, defining the level of criticality applied to each software component. DO-178C is based on the idea that you cannot ‘test’ quality into a product at the end. Instead, safety must be designed into every step of the development life cycle. It focuses heavily on being traceable, meaning every line of code must be linked back to a specific requirement, and every requirement must be tested. The rigor of the process depends on how critical the software is to the safety of the flight. This is known as the Design Assurance Levels (DAL) and ranges from level A – catastrophic – to level E – no effect. For example, systems such as flight controls and autopilot are DAL A, braking systems are DAL B, flight management systems are DAL C, maintenance data recorders are DAL D, and in-flight entertainment systems are DAL E. Replacing DO-178B DO-178C (released in 2011) replaced the older DO-178B. While the core processes remained similar, “C” added four critical supplements to address modern technology. These are; DO-330: Software Tool Qualification, DO-331: Model-Based Development and Verification, DO-332: Object-Oriented Technology, and DO-333: Formal Methods. DO-330 governs software tool qualification. Should a tool be employed to automate a process, such as a compiler or a code generator, a defect within that tool carries the potential to introduce an error into the flight software. DO-330 establishes the rigorous process for demonstrating that the tools utilised possess a level of reliability commensurate with the code they generate. Historically, engineers would document requirements in natural language (such as English) before implementing the corresponding code, typically in C. With the adoption of DO-331, which governs Model-Based Development (MBD), the specification can now be formulated as a visual, mathematical model, utilising tools like Simulink. This model serves as the definitive specification and, in certain instances, is employed to automatically generate the resultant code. Features in languages such as C++, Ada, and Java, including inheritance, polymorphism, and dynamic memory allocation, present risks within a cockpit environment due to their potential to introduce unpredictable software behavior. DO-332 addresses this by stipulating ‘Local Type Consistency’ rules and stringent requirements governing the usage of these features to ensure the execution path remains deterministic and amenable to testing. Finally, DO-333 represents the pinnacle of verification standards. Rather than relying solely on testing the code with various inputs to identify failures, this standard employs mathematical logic to formally prove the code’s correctness. While testing can merely demonstrate the existence of defects, formal methods offer a mathematical proof of the absence of certain critical errors, such as a divide-by-zero calculation, within the codebase. Requirements for certification Achieving certification under rigorous standards such as DO-178C for airborne software constitutes a comprehensive, document-intensive undertaking. A project is obligated to generate a substantial volume of documentation, which serves as undeniable evidence of compliance with the defined safety objectives. This documentation must span the entirety of the software development lifecycle and encompass several critical domains: The Plan for Software Aspects of Certification (PSAC) is a foundational document that functions as the project’s contract with the certification authorities. It meticulously details the overall strategy for software development, delineating how the project team intends to interpret and satisfy the DO-178C objectives. Furthermore, it establishes the scope, life cycle processes, standards, and the specific artifacts designated for review. Then, the requirements documentation phase necessitates the meticulous definition of the software’s intended behavior. This is typically divided into high-level requirements (HLRs) and Low-Level Requirements (LLRs). HLRs define what the system is required to accomplish from an operational and safety perspective, frequently being derived directly from system requirements. They describe the functional, performance, and safety-critical behaviors of the software. LLRs detail how the software shall be structured and implemented to successfully satisfy the HLRs. They must be directly traceable to the source code and specify the internal design, interfaces, and algorithms. Next, the verification and validation phase is arguably the most resource-intensive, particularly for the highest level of safety criticality. Verification is crucial to prove the software meets requirements and has no unwanted features. Verification methods in DO-178C include reviews and analysis, which encompasses static analysis of the code, control flow analysis, and data flow analysis. It also includes testing, which involves thorough testing conducted across unit, integration, and system levels, and finally Modified Condition/Decision Coverage (MC/DC) analysis. MC/DC is a mandatory and highly stringent verification technique for Design Assurance Level A software. It stipulates that every condition within a decision in the code must be demonstrated to independently affect the outcome of that decision. This rigorous coverage requirement provides assurance that every logical path and gate within the code functions correctly and independently, furnishing the highest level of confidence against logic errors, and the effort involved in attaining 100% MC/DC is a principal driver of cost and schedule. Next, Configuration Management (CM) and Quality Assurance (QA) are essential processes to ensure the integrity and control of the entire development process. Configuration Management is a vital system for maintaining traceability and version control, ensuring that only the exact version of the source code, object code, executable module, requirements, design, and test cases that have been fully tested and verified are approved for operational use (i.e., “flown”), which effectively eliminates the risk of deploying an untested or improperly modified version. Meanwhile, Quality Assurance monitors the entire software life cycle to ensure that all planned processes, standards, and procedures, as stipulated in the PSAC, are correctly and consistently adhered to. The level of rigor mandated by DAL A (Catastrophic failure condition) is so extreme that the effort, expenditure, and time necessary for the verification of the code, specifically the achievement of MC/DC, frequently surpasses the resources allocated to the initial writing of the code itself. This difference highlights the extremely high bar for proving the software is safe and reliable for the most critical functions on an aircraft. Why does it matter? The inherent complexity of contemporary fly by wire aircraft mandates an exceptionally rigorous and structured methodology for software development. This requirement is satisfied by DO-178C. Without this standard, it would be extremely difficult to securely and reliably manage the complex, integrated software that controls essential aircraft functions like flight surfaces, engine thrust, navigation, and surveillance. DO-178C imposes an unparalleled degree of discipline upon engineering teams throughout the entirety of the software lifecycle. It necessitates a stringent process encompassing planning, development, verification, and configuration management. This comprehensive framework is specifically engineered to eliminate, or at least mitigate to an acceptable level, the risks associated with software anomalies. It ensures that every single line of code is demonstrably traceable to a specific high-level requirement and is subjected to exhaustive testing. This preventative measure stops unexpected code, a hidden dependency, or an undocumented feature from causing a catastrophic system failure or loss of life. While the precise number of lives saved by DO-178C is immeasurable, its profound impact on aviation safety is incontrovertible. It is globally recognised and accepted by regulatory bodies, including the FAA and EASA, as the international de facto benchmark for certifying the safety and airworthiness of all software employed in civil airborne systems. Its implementation directly prevents potential catastrophic failures in mission critical systems such as primary flight control computers, sophisticated navigation suites, including GPS and Flight Management Systems, and advanced surveillance technology like Traffic alert and Collision Avoidance System. By enforcing this superior level of quality and rigour, DO-178C fundamentally underpins public confidence in the safety of air travel. With expertise spanning electrical, electronic, software engineering, and business development, Andrew brings a unique, system-level understanding of safety-critical design. This ensures that WHIS solutions are grounded in real-world engineering challenges, giving customers confidence that performance, safety, and precision are built in from the start. https://www.aerospacetestinginternational.com/opinion/explaining-do-178c-the-safety-standard-for-software-in-aviation.html CALENDAR OF EVENTS . ALPA's 70th Air Safety Forum -September 14-17, 2026; Washington, DC . ICAO/EASA Third Global RSOO/RAIO Forum for Aviation Safety — September 29–30, 2026, in Georgetown, Guyana., https://www.icao.int/events : NATA Ground Handling Safety Symposium - September 15-16, 2026 Dallas/Fort Worth, TX www.nata.aero/ghss : Aircraft Cabin Air International Conference - 22-23 September 2026 . ISASI - BOSTON 2026 - September 28, 2026 – October 2, 2026 . Global Aviation Conference Frankfurt- 29-30SEP2026 - Frankfurt, Germany . Defence Aviation Safety Conference 2026 — October 5–6, 2026, United Kingdom. . European Aviation Training Summit 3 – 5 November 2026 • Estoril Congress Centre, Cascais, Portugal . 79TH ANNUAL INTERNATIONAL AVIATION SAFETY SUMMIT MONTREAL | NOVEMBER 10-12, 2026. . Airlines 2026 conference - November 11, 2026 (London) . 2026 NBAA Business Aviation Convention & Exhibition (NBAA-BACE) Oct. 20-22, 2026 | Las Vegas, NV . Bombardier Safety Standdown (November 10–12, 2026 in Wichita, KS) . 2027 ACSF Safety Symposium - April 6-8, 2027 - ERAU Daytona Beach, FL Curt Lewis