Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9

Post originally Published February 5, 2024 || Last Updated February 5, 2024

See how everyone can now afford to fly Business Class and book 5 Star Hotels with Mighty Travels Premium! Get started for free.

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The A380's Steep Operating Costs

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9

The Airbus A380 superjumbo jet was meant to revolutionize air travel when it first took flight in 2007. With a maximum capacity of over 800 passengers, the double-decker aircraft promised economies of scale that would allow airlines to lower fares and increase profitability. However, the A380 has faced steep operating costs that have made it difficult for carriers to leverage its massive size.

One major issue has been the A380's four engines. While newer twin-engine aircraft like the Boeing 787 are increasingly efficient, operating four engines substantially raises fuel costs. Maintenance is also more intensive and expensive on the A380. Its huge wingspan and weight put greater strain on the airframe and require more frequent inspections. The plane's large size also limits the number of airports it can service, as many do not have gates that can accommodate it.
These factors have hampered the A380's operational flexibility and profit potential. Air France estimated its cost per available seat kilometer was over 10% higher on the A380 versus its 777s. Qantas found its A380 flights were profitable on high-demand routes like London, but lost money on lower-volume destinations. Without enough passengers to fill all 800 seats, the A380's operating costs were spread across fewer travelers, making it harder to break even.

The Covid-19 pandemic has only exacerbated these challenges. With demand for long-haul international travel plummeting, many A380s have been grounded indefinitely. Air France, Lufthansa and Qantas permanently retired their A380 fleets as the recovery timeline remains uncertain. Operating such large aircraft with depressed loads is simply economically unviable.

What else is in this post?

  1. Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The A380's Steep Operating Costs
  2. Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The 787 Battery Fires of 2013
  3. Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - Cracks in the Wings of the Airbus A380
  4. Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The McDonnell Douglas DC-10's Cargo Door Issues
  5. Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - Electrical Faults Plaguing the Airbus A350
  6. Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The De Havilland Comet and Metal Fatigue
  7. Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - Boeing 777 Engine Reliability Concerns
  8. Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The Boeing 737 Rudder Reversal Accidents

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The 787 Battery Fires of 2013

The 787 Dreamliner entered service in 2011 as Boeing's most advanced aircraft to date. Using lightweight composite materials and powerful electrical systems, the 787 promised unparalleled fuel efficiency and passenger comfort. However, in early 2013, a series of battery fires on 787s operated by All Nippon Airways and Japan Airlines led to the entire fleet being grounded for months.
Investigations found the fires originated from the 787's lithium-ion battery packs. These revolutionary batteries delivered major weight savings versus traditional nickel-cadmium units, supporting the 787's design advances. However, their chemistry made them prone to uncontrolled temperature spikes if manufacturing defects were present. Once overheating began, the batteries could enter a hazardous thermal runaway condition and ignite.

The root causes were traced to subcontracted battery maker GS Yuasa. Production flaws led to internal cell faults that allowed uncontrolled current flows within the battery. Quality control failed to detect these defects before the packs were installed on aircraft. While it was tempting to see the issues as solely a supplier problem, Boeing bore responsibility too. Its engineers failed to consider the worst possible failure modes of the new battery technology. Safety systems did not prevent catastrophic cell failures or the spread of fires between battery cells once ignited.
With its fleet grounded, Boeing worked urgently to develop containment solutions. The battery packs were re-engineered with improved insulation, heat venting and fire suppression capabilities. This multi-level protection approach ensured overheating cells could not ignite adjacent components. Changes to production methods tightened quality control and eliminated the manufacturing issues.

The 787 debacle was a painful lesson on the risks of pushing technology advancements too far, too fast without exhaustive safeguards. While Boeing's zeal for innovation delivered a truly game-changing aircraft with the 787, it came at the cost of adequate failure mode analysis. With a brand-new plane grounded months into service, Boeing's reputation and credibility suffered. Airlines were forced to cancel 787 flights, rearrange schedules and lease replacement aircraft. Both Boeing and Yuasa incurred huge costs to fix the battery issue.

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - Cracks in the Wings of the Airbus A380

In early 2012, over 40 hairline cracks were detected in the wings of several Airbus A380 superjumbos during routine inspections. While not inherently dangerous, these small fractures in the aircraft’s wing ribs raised concerns over the long-term durability of the A380 airframe. For an aircraft meant to have a service life of over 25 years, such early signs of metal fatigue were troubling.

The cracks originated near brackets that connect the wing’s exterior paneling to its internal rib structure. These ribs give the wings their strength and ability to flex during flight. The brackets experience substantial stress from aerodynamic forces, vibration, and the flexing of the wings during takeoff and landing. Over time, these forces can cause microscopic fractures in the wings’ aluminum alloy material that propagate into visible cracks.
Qantas and Singapore Airlines were among the first to detect the cracks in their A380 fleets back in early 2012. Airbus determined that manufacturing stresses from the riveting process contributed to the bracket cracks starting prematurely. Nonetheless, such metal fatigue remains a fact of life for all aircraft as they age. No plane type is immune from the slow accumulation of nearly imperceptible cracks over thousands of flight cycles.

While the A380 cracks did not pose an imminent airworthiness concern, Airbus could not leave them unaddressed. The aircraft maker worked swiftly to inspect the entire A380 fleet and enact repairs. Cracked brackets were reinforced with additional riveting to reduce local stress levels. The wing ribs themselves were retrofitted with improved carbon fiber-reinforced polymer strips to limit flexing near the brackets. Together, these enhancements aimed to prevent further cracking as the aircraft continued operating.
By late 2012, over a third of the global A380 fleet had been inspected and repaired where needed. The rapid response demonstrated Airbus’s commitment to the A380’s long-term viability despite its disappointing sales. While every new aircraft model experiences teething issues, Airbus could ill affordAnything negative for its prestige flagship jet. With the enhanced brackets and ribs, Airbus asserted the cracks did not indicate any fundamental design flaws that jeopardized the A380’s intended service duration.

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The McDonnell Douglas DC-10's Cargo Door Issues

The McDonnell Douglas DC-10 entered airline service in 1971 as a new wide-body aircraft aimed at high-capacity, long-haul routes. Early on though, the DC-10 gained an unfortunate reputation for deadly cargo door failures that cast a pall over its commercial success. In 1972, just a year after its debut, a DC-10 operated by American Airlines suffered an explosive decompression shortly after takeoff that resulted in a horrific crash killing 46 people. Investigations revealed that the aircraft’s complex cargo door latch had inadvertently been left unlatched before the flight by ground crew. As the cabin pressurized during ascent, the unsecured door violently blew open causing massive structural damage. Without today’s tougher aviation regulations, the cargo door flaw was left unaddressed. Tragically, in 1974 a Turkish Airlines DC-10 crashed in almost identical fashion, killing 346 passengers and crew.
With the public outraged, the US Federal Aviation Administration finally mandated significant redesigns to the DC-10’s cargo door mechanisms. The latches were strengthened and a visual warning system added to clearly alert the flight crew if the door was not properly latched before takeoff. For airlines operating the DC-10, these fixes were costly and time consuming to implement across their entire fleet. Worse still, public confidence in the DC-10 was severely shaken by the crashes. Some airline passengers went so far as to rebook their travel plans if flying on a DC-10. And who could blame them – at the time, the DC-10 had suffered 3 major crashes killing nearly 400 people after just 3 years in service.

For McDonnell Douglas, the negative publicity around the DC-10 cargo doors proved to be a reputational scar from which the aircraft never fully recovered. Up against more reliable wide-bodies likes the 747 from arch-rival Boeing, airlines shied away from buying the DC-10 despite its innovations. McDonnell Douglas also took a huge financial hit from lawsuits and settlement costs stemming from the crashes. While design changes did finally resolve the door issue, the damage was already done. The DC-10 was seen by airlines and passengers alike as an unsafe aircraft prone to catastrophic accidents versus a capable long-haul jet that happened to have a fixable flaw.

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - Electrical Faults Plaguing the Airbus A350

As Airbus’ newest wide-body aircraft, the A350 XWB has been a commercial success for the European aerospace giant since entering service in 2015. Over 900 orders have been placed by leading carriers worldwide attracted by its fuel efficiency, range capabilities and passenger comforts. However, during early operations of the A350, a troubling pattern of electrical faults emerged that affected critical systems and compromised safety margins.

One of the most alarming issues involved the aircraft’s electrical generation system. During some flights, voltages became unstable and wild fluctuations occurred between the A350’s electrical networks. This caused computers to reset and multiple flight-critical systems to fail including airspeed indicators, wing slat controls and engine systems. On a few occasions, total electrical failure was only narrowly avoided through emergency procedures.

The root cause was traced to defective power control units that managed the electrical generators. Substandard soldering during manufacturing left these circuit boards prone to partial shorts. Components then overheated mid-flight under heavy electrical loads leading to failures. While Airbus quickly instituted improved quality control and testing to weed out bad circuit boards, the frequency of electrical faults remained higher than comparable long-haul jets during the A350’s first two years of service.

Equally worrying were electrical fires that broke out on empty A350s undergoing pre-delivery testing on the ground. Sparking wires and overheating junction boxes in the cockpit indicated vulnerabilities in how electrical systems were integrated that could put pilots and passengers at risk in flight. Heat damage was extensive enough in some occurrences that aircraft delivery delays stretched into months.
Airbus dispatched engineers to airlines operating the A350 to meticulously inspect electrical components and wiring for any defects. Updated maintenance procedures were also introduced focusing on prevention and early detection of any electrical instabilities. Yet questions lingered if latent flaws still existed that could trigger serious mid-air faults years into the future after hundreds of flight cycles.

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The De Havilland Comet and Metal Fatigue

The ill-fated de Havilland Comet entered service in 1952 as the world’s first commercial jet airliner. With its high cruising speed and smooth flights, the Comet promised a revolution in passenger comfort for the nascent jet age. However, a series of fatal mid-flight breakups grounded the entire Comet fleet by 1954 and nearly spelled the end for de Havilland. Investigations ultimately revealed metal fatigue around the aircraft’s square cabin window corners as the primary cause. The Comet accidents spotlighted this little known phenomenon as a grave danger for pressurized aircraft.
When cruising at high altitudes, commercial jets must maintain significantly higher air pressure inside the cabin versus the very low external pressures. This pressure differential places heavy structural stresses on the exterior fuselage, demanding rigorous analysis of metal fatigue during the design process. On the Comet, the shape of its patented square windows concentrated stresses sharply at the window corners. After repeated pressurization cycles during flights, microscopic cracks began forming in the metal skin around the windows. These cracks propagated over time until catastrophic rupture occurred, tearing off sections of the fuselage.

With each subsequent crash investigation, de Havilland reinforced the fuselage and window corners in an attempt to address the structural flaws. However, the basic square shape remained vulnerable to metal fatigue. Moreover, the aviation industry’s understanding of metal fatigue factors like crack propagation rates and cyclical stress thresholds was highly primitive at the time. De Havilland ultimately redesigned the Comet with safer oval cabin windows that distributed stresses more uniformly. But by then, the damage was already done to the Comet’s reputation.
The hard lessons from the Comet accidents spurred intensive research across the budding jetliner industry on metal fatigue science and structural testing methods. Aircraft manufacturers like Boeing took meticulous care analyzing stress points across the entire airframe, not just around windows, as they developed new jet models. Today's rigorous aircraft certification standards reflect the critical insights on metal fatigue gained from the devastating Comet crashes in the 1950s.

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - Boeing 777 Engine Reliability Concerns

The Boeing 777 first entered service back in 1995 and has compiled an impressive safety record across its passenger and cargo variants. Over 2,000 777s have been delivered with over 400 million flight hours logged to date. However, while the aircraft itself has proven remarkably reliable, the same cannot be said of the GE90 turbofan engines that power the 777. This mammoth engine remains the largest ever mounted on a commercial jet. But with great power comes great responsibility when it comes to maintenance.

Cracks in the GE90 turbine blades have emerged as an ongoing headache for airlines operating the Boeing 777. These cracks originate from normal wear and tear factors like fatigue, corrosion and foreign object damage. However, worse than expected corrosion has occurred internally in the hollow titanium blades where high pressure air from the combustor section passes through. Fractures then form in the internal walls of the blades, releasing high energy debris when they finally rupture that can cause catastrophic secondary damage.
United Airlines, with over 150 GE90-powered 777s, has been the most vocal about durability issues with the engines. Back in 2018, the airline was forced to prematurely retire dozens of GE90s after inspections uncovered dangerous internal cracks in the high pressure turbine section. Customers were disrupted by canceled flights as United scrambled to swap out failed engines.

Even after significant redesigns by GE Aviation, the GE90 continues to suffer more turbine blade fractures than comparable engines like the Rolls-Royce Trent 800 powering some 777s. The root cause lies in the extreme demands placed on the GE90 to generate the massive 100,000+ pound thrust needed for the 777. This results in turbine inlet temperatures over the melting point of titanium alloy blades. Complex air cooling schemes help prevent melting, but sustained exposure to such heat inevitably takes a toll over time.

Grounded: 4 Problem Planes Beyond the Boeing 737 Max 9 - The Boeing 737 Rudder Reversal Accidents

The rudder is one of the most critical control surfaces on any aircraft, providing directional stability and allowing pilots to steer the plane. On the Boeing 737, a series of deadly rudder malfunctions in the 1990s eroded confidence in this workhorse narrowbody jet that formed the backbone of many airline fleets.

During several 737 flights, sudden uncommanded full rudder deflections occurred for no apparent reason. With the rudder jammed at its maximum limit, pilots lost control of the aircraft which entered severe rolls and violent dives. In 1991, a 737-200 operated by United Airlines experienced a rudder hardover while cruising at altitude. Despite the crew's valiant efforts, they could not regain control and the aircraft crashed near Colorado Springs killing all 25 on board. Then in 1994, during approach into Pittsburgh, another 737-300 suddenly suffered a rudder malfunction putting it into a steep bank. The pilots ultimately impacted the ground at high speed, resulting in the loss of 132 lives.

Investigations revealed that a defective propulsion control unit could trigger sudden rudder movements on the 737. This critical hydraulic component was originally prone to jamming due to internal wear of its servo valve. Under certain flight conditions, the jammed valve would deflect the rudder to its maximum limit. The surprised pilots would be unable to manually override the rudder due to high aerodynamic forces acting on it at speed.

The root causes were deeply concerning for a liner in service for over 25 years and meant to have intrinsic fail safe redundancy in critical systems. However, the troubling tendency for rudder malfunctions resulting in unrecoverable loss of control did not surface until the 1990s. This highlighted that simply assuming a system's redundancy will contain any potential latent flaws is dangerous. Just because a problem had not occurred before, does not mean foolproof safeguards exist if it ever does.

See how everyone can now afford to fly Business Class and book 5 Star Hotels with Mighty Travels Premium! Get started for free.