Delta to Update 767-400 Aircraft with DeltaOne Suites

For 2019, Delta’s 767-400 fleet will receive the DeltaOne Suites to replace the DeltaOne lie-flat seating. These planes are used on some transcon routes (JFK to LAX and SFO), as well as certain transatlantic flights.

delta 767400 takeoff

 On transcon routes, Delta uses the 757-200, the 767-300, and the 767-400. Which planes are used on each flight changes seasonally and based on demand. All these aircraft offer lie-flat seating in the DeltaOne business class cabin. The 757 has the newest seats, while the 767 models have older seating and IFE systems. I prefer the widebody layout of the 767, but these cabins are ready for an update (they’re about 10 years old). The 767-400 models were delivered from Boeing to Delta from 2000 to 2002, so there is still considerable life in the frames.

Delta operates 58 767-300s and 21 767-400 models. There are two very old -300 models that never got the lie-flat cabin update and still feature the recliner-style first class. These two aircraft will be removed from service in 2019. Most of the other 56 -300 models are scheduled for the DeltaOne suites upgrade by 2021, but after the -400 models.

We don’t have an exact timeline of when the 21 -400 models will be taken out of service to be upgraded, but it seems like work has started, and that most of the -400 fleet should be updated in 2019, with some potentially finishing in 2020.

The current 767-400 features 246 total seats, with 40 in DeltaOne lie-flat business class, 28 in ComfortPlus, and 178 in Economy. The updated versions will feature 34 DeltaOne Suites in business class, 20 PremiumSelect seats, the same 28 ComfortPlus seats, and 156 Economy seats, for a total of 238.

deltaone suites

The DeltaOne suites are a fantastic business class product. They are featured on Delta’s flagship A350 models, and by the end of 2019 will be retrofitted to all Boeing 777 aircraft. Delta will also be receiving brand-new Airbus A330neo models starting in 2019, which will replace some of the older 767-300 aircraft, and these new Airbus models will come with the suites as well. This will align Delta’s product offerings across its widebody fleet.

The DeltaOne business class suites offer aisle access, sliding doors, lie-flat seating, and 18” screens. When these suites become available on transcon operations, it will give Delta a significant advantage over American and United. American currently uses the A321T with first and business class seating but does not have a suite product. United has been rolling out two versions of Polaris seating, but it has not been consistent and they do not have a suite equivalent. They also use 757 with lie-flat seating on some transcon routes. United, to its credit, has been flying Polaris-equipped 777 and 787 planes occasionally on these routes. JetBlue features its Mint product, which has lie-flat seating with two semi-suites mixed in.

delta one suites2

There has been no additional information released regarding what else will be upgraded on the 767s. I would bet that there will be at least minor upgrades to the bathrooms, luggage bin designs, interior lighting, and some of the trim/paneling. I would also assume that the rest of the cabin (not the suites) will get Delta’s new wireless IFE system that debuted this year on the A220 aircraft.

There are a few interesting questions here, which Delta yet to provide details :

      • How will the DeltaOne Suites, which debuted on the Airbus A350 two years ago, be set up on the 767, which is narrower than the A350? The best guess is that they will be slightly narrower versions of the suite, but still be configured in a 1-2-1 set up. There is a possibility that some may be staggered due to width restrictions.
      • Where will the updated 767-400s fly to? Most likely, they will go to the international routes first, while the older 767-300s fill in on the transcon routes until all the planes are updated. We may see some occasional A330 use on these routes as the planes enter and leave service.
      • As far as complimentary upgrades go, Medallion members currently can upgrade into DeltaOne on the transcon flights – will this happen with the new suites, or will complimentary upgrades only include ComfortPlus and/or PremiumSelect?

Overall, the DeltaOne Suites will be an exciting and well-needed addition across Delta’s wide-body fleet.

Updated Information on the 737 MAX Crashes

Updated Information on the 737 MAX Crashes

As in most news and media releases, there is a lot of inconclusive reporting and speculation added to facts. Let’s set the record straight with updated, reliable information that has come out this week.

RENTON, WA - JANUARY 29: A Boeing 737 MAX 8 airliner lifts off for its first flight on January 29, 2016 in Renton, State. The 737 MAX is the newest of Boeing's most popular airliner featuring more futel efficient engines and redesigned wings. (Photo by Stephen Brashear/Getty Images)

The FAA and Boeing

The FAA is the regulatory body that needs to sign off on the airworthiness of any airplane that will fly in the US. This could be a very lengthy process on a brand-new aircraft, since every detail and design feature must be tested and approved. One item they test for is redundancy (if one part breaks, the plane needs to operate on the backup part). This is crucial in a plane, less so in a car for example, since the car can pull over if a part malfunctions. We’ve seen engineering mistakes and a lack of redundancy as a factor in many crashes

When the 737 MAX came out, it was not considered an all-new plane, but an update on previous 737 models. Therefore, the FAA used more lenient guidelines in testing the MAX models for airworthiness. Currently, we don’t know how much more relaxed this process was, but there’s a chance that the FAA missed testing all parameters of every system in the 737 MAX tests.

We do have access to some reports that say Boeing gave certain guidelines to the FAA and then released the plane with different operating characteristics. Boeing initially told the FAA that the MCAS computer could only manipulate the plane a small amount up and down, and in actuality the computers could move the plane more than 4 times what Boeing initially reported.

Issue #1 : Is Boeing at fault for releasing potentially incorrect information, or for changing the characteristics of the plane’s systems after the FAA approved airworthiness? Some say this is Boeing “cheating” to pass the tests, and that the FAA would have never approved the computers having the power to change the angles of flight as much as they can. Is the FAA at fault for not properly testing the full capabilities of the plane? Perhaps they took Boeing’s word on certain features and decided not to fully test the entire envelope? The agency could be stretched for time or manpower, or it could have outdated testing procedures. If the entire focus of the agency is to approve airworthiness of planes, something seems amiss in the 737 MAX review.

Boeing and Pilots

Boeing, as the manufacturer of the 737 MAX, is responsible for creating the flight manuals. While MCAS is included in the manuals, the explicit details of its operation and the entire potential operating parameters are excluded. Boeing is saying that including too much detail is not necessary for the pilots, as MCAS was only supposed to intervene in extreme situations. Any well-trained pilot should know how to overcome a stall. Pilot associations are not delighted with the lack of detail in the manuals, but we’ve now had numerous incidents where pilots have had MCAS intervene, and correctly overridden it. This has happened on four occasions in the US, and on the Lion Air flight the day before Lion Air 610 crashed.

Issue #2 : Is Boeing at fault for not including the full information in the manual? Is the FAA at fault for not requiring this level of detail before the plane is released? Why have some pilots been able to recognize MCAS engagement, and correctly disable it, while others have not?

lion air max 8

The Airlines and Training and Maintenance

Maintenance, parts installation, and training are the responsibility of the airline, not the manufacturer. Different countries have different training guidelines and requirements. The US is among the strictest, while other countries allow pilots to fly with less hours (The US requires 1,500 hours, while the Lion Air co-pilot was flying with 350). Is this a factor in any of the crashes? The Lion Air flight the day before the crash was able to recover thanks to an off-duty pilot sitting in the jump-seat who recognized MCAS and intervened. The two on duty pilots did not know what to do. This suggests that the off-duty Lion Air pilot knew about MCAS and was either more experienced or better trained or both. The next day, the pilots of 610 were either not lucky, less well trained, or were not aware of MCAS.

MCAS uses two sensors to determine a stall. These were reported as faulty on two flights before Lion Air 610 and changed twice. Was the issue resolved? Or were the sensors still not functioning, therefore giving MCAS incorrect information. In normal flight, MCAS shouldn’t kick in at all. So why did it?

Where was the fail-safe redundancy on these sensors? As currently set up, MCAS reads only one sensor if the two sensors don’t match. Instead, it should shut off and send the pilots a warning that the data from the sensors isn’t the same. Where was the FAA on signing off on this?

After the Lion Air crash, Boeing sent out a bulletin to all operators with updated MCAS information. However, Ethiopian Airlines did not have a simulator for the 737 MAX until January 2019 (they only had a 737 NG simulator). In March 2019, an MCAS scenario was added to the simulator. Flight crews are required to go through simulator training every 6 months, so there is a possibility the crew never trained on the MCAS system in the MAX simulator.

Issue #3 : Why are some pilots able to recognize MCAS and deal with it appropriately? At first, airlines were claiming that they never knew about MCAS and it was never included in Boeing’s guides. Yet plenty of pilots knew about it and operated accordingly. So, is this a situation where some pilots are too inexperienced to deal with the full range of operations (they are great at flying straight and in nice weather, but anything else and their lack of experience shows?). Or did Lion Air not get around to training some pilots on the new plane yet? What about training guidelines at Ethiopian? Could those pilots never have trained on a 737 MAX?

Issue #4 : What role does potentially improper maintenance and broken sensors play in MCAS? Is the system at fault for doing what it’s supposed to do (saving the plane for a stall), if it’s reading incorrect info? And why was MCAS not tested with safety redundancies in the first place?

What I Think Will Play Out

Air crashes are never the result of one factor, but a string of events and issues that come together under extreme circumstances. I don’t think we’ll see the blame placed on one body here but spread across numerous factors. Let’s also keep in mind that a full analysis of the data from Lion Air 610 has not yet been completed, and that we have minimal information on Ethiopia 302 as of this writing.

Boeing will need to provide all the details for MCAS in manuals and provide a more comprehensive roll out of the system. With the system update that went out to airlines for installation this week, we see that MCAS has slightly reduced parameters, so that it will make less drastic control changes and be easier to override. Boeing, legally, may not be at fault, but it will have to reimburse airlines for the costs of groundings, and its reputation regarding the 737 MAX won’t be as bulletproof as before. Boeing’s argument that well-trained pilots know how to prevent a stall will stand, as we’ve seen it in flight, but airlines will see that as pushing blame on to them.

The FAA will be probed for lackadaisical approval procedures, and all updates to planes may have to go through the same process as new models. There will be more oversight into the interactions between the regulatory bodies and the manufacturers, both in the US and abroad.

Certain airlines will come under fire for questionable maintenance practices (why did Lion Air 610 fly while rated not airworthy?) and requirements for pilot training will become more stringent, especially outside the US.

Airplane Groundings

Airplane groundings

Have there been previous groundings of planes in the US?

There have been two major groundings of planes by the FAA (Federal Aviation Administration) in the US, not including the current 737 MAX situation. These groundings were for an entire model range, not a subset of an aircraft model. The most recent one, and one that many people are familiar with, was for the Boeing 787 Dreamliner in 2013. The other model-wide grounding occurred in 1979, when the US banned the DC-10 after a horrific crash in 1979.

787 dreamliner grounding

The Boeing 787 Dreamliner

The Boeing 787 Dreamliner was an all-new aircraft design, first flying in 2009 and starting commercial service in 2011 with ANA Airways. There are nearly 1,500 orders as of early 2019 with more than half having been delivered. Although problems are common in the first year of a new aircraft’s life, after a number of incidents, including an electrical fire aboard an ANA 787 and a similar fire found on a JAL 787 at Boston’s Logan Airport, the FAA ordered a review into the design and manufacture of the Dreamliner. This was quickly followed with a full grounding of the entire 787 fleet.

Only two US airlines, United Airlines and American Airlines, operated the Dreamliner in 2013. Chile’s Directorate General of Civil Aviation grounded LAN Airlines’ three 787s. The Indian Directorate General of Civil Aviation directed Air India to ground its six Dreamliners. The Japanese Transport Ministry made the ANA and JAL groundings official in Japan and indefinite following the FAA’s announcement. The European Aviation Safety Agency also followed the FAA’s advice and grounded the only two European 787s, which were operated by LOT Polish Airlines. Qatar Airways announced it was grounding its five Dreamliners. Ethiopian Air was the final operator to announce groundings of its four 787 aircraft.

After it completed an investigation of the electrical and battery issues on the Dreamliner, the NTSB released a report in late 2014, which assigned blame to several groups:

    • GS Yuasa of Japan, for battery manufacturing methods that could introduce defects that were caught after inspection timelines
    • Boeing’s engineers, who failed to consider and test for certain worst-case battery failures
    • The FAA, which failed to recognize the potential hazard and did not require proper tests as part of the certification process

The battery incidents were considered thermal runaways (similar to overheating), were not contained in a safe manner, and happened much sooner than Boeing & parts suppliers had estimated. There was a significant chance of these incidents happening again or causing even worse damage (the JAL 787 battery caught fire on the ground; obviously could’ve been a much worse outcome had it happened in the air). By April 2013, the FAA allowed Dreamliners to return to service, once Boeing equipped them with upgraded battery and fire protection systems.

Reports estimate the cost of the grounding to be around $110M for ANA and JAL combined, which operated about half of the 50 Dreamliners in 2013. Overall, the groundings expected to cost Boeing approximately $600M. This total comes from the carriers expecting reimbursement of their losses from Boeing, as well as Boeing halting production of the 787 while the investigation moved forward.

The McDonnell Douglas DC-10

In the 1970s, Boeing dominated international long-haul travel with it’s wide-body 747. Competitors McDonnell Douglas and Lockheed Martin scrambled for a plane that could fly almost as far but was cheaper to operate. It was to be used on domestic transcontinental and transatlantic routes. Both companies came out with very similar models, dubbed the tri-jets (due to their three engines). These planes were everywhere in the late 1970s and early 1980s but disappeared from commercial aviation somewhat quickly.

While Lockheed’s tri-jet, the L1011 TriStar, didn’t achieve much volume in sales, the DC-10 was selling decently but was plagued with design problems. First, a flaw in the cargo doors caused them to blow out in flight, resulting in rapid decompression and sometimes crashes (American Airlines Flight 96 in 1972 and Turkish Airlines Flight 981 in 1974). Second, the DC-10 was involved in some bad publicity that was indirectly associated with the manufacturers design. In 1973, National Airlines flight 73 had an engine failure, blowing out a window and killing a passenger. In 1978, Continental Flight 603 had a tire issue on takeoff, causing a massive fire which killed two passengers. In 1979, Western Airlines Flight 2605 landed on the wrong runway in Mexico City, killing almost all on board.

In 1979, American Airlines Flight 191 crashed in Chicago after an engine separated from the wing on takeoff. The wing ripping off caused the hydraulic lines and their backups to be severed, which all ran together in the same part of the wing, a result of poor design. 273 people were killed, making this the deadliest crash in US history. Perhaps because this happened in daylight and in view of many people both at the airport and on the ground nearby, and because a photographer caught the plane on fire seconds before hitting the ground, this was one of the first crashes to be extensively covered by the media. The horrific reports and photos spread quickly throughout the public and was essentially a nail in the coffin for the DC-10 in the minds of the public.

american airlines 191

The FAA grounded all DC-10s, 138 of which were operated by US airlines. McDonnell Douglas quickly implemented changes to the hydraulic system and safety controls, and the planes were returned to service five weeks later. The full investigation found that improper maintenance led to the engine separating, but that design flaws prohibited pilots from maintaining flight control. When the DC-10 returned to service, its reputation never recovered. At the end of 1979, Air New Zealand Flight 901 crashed in Antarctica as result of poor flight planning and severe weather conditions. In 1982, World Airways Flight 30 didn’t stop in time on the runway in Boston and crashed into the harbor. There were numerous other crashes of DC-10 aircraft throughout the 1980’s, but the decade ended with the crash of United Flight 232, which crashed after an engine exploded and blew out hydraulic lines, making the aircraft uncontrollable. Although some survived the crash, 111 died. There was a very public investigation, and by the 1990s the DC-10, was relegated to mainly cargo flights.

The costs of the recent grounding of the 737 MAX

Analysts estimate that a 2-month grounding of the MAX would cost Boeing approximately $5B. These costs would initially come from reimbursing airlines for lost revenue as well as halting production and delivery of new planes. Other costs of grounding the plane would come from plane parking and airport fees, idle crews, and rescheduling factory work and supplier deliveries.


Updates on the 737 MAX Crashes

Updates on the 737 MAX Crashes

balck box et302

The data from ET302 has now been read, and pending a final official report, there is preliminary information that it was a very similar incident to Lion Air 610. Meaning that after takeoff, something went wrong involving MCAS, and the pilots were unable to regain control of the 737 MAX.

There are no updates on the part of the investigation that involves the faulty sensors and maintenance on Lion Air 610. It’s too early to know if this will factor in to the Ethiopian crash as well.

The issue here is whether MCAS is a flawed system or if it was being fed incorrect data from poorly maintained parts. We also have reports that MCAS has kicked in on other flights, even in the US, and pilots were able to recover without a problem. Will airlines training procedures come into play in this investigation as well? Why were some pilots able to work with MCAS while others weren’t?

There are some reports detailing the FAA’s process for approving the 737 MAX for flight. The FAA is responsible for making sure any products from a manufacturer are approved for flight. They act as a second monitor or as checks and balances to Boeing and Airbus, rather than the public just assuming the planes are air-worthy based on manufacturers’ claims.

The Seattle Times has gotten information suggesting that the FAA only partially checked into the 737 MAX’s MCAS system. The analysis suggests that MCAS can move flight controls 4x more than in the initial reports from Boeing and the FAA (this could affect the very dramatic nose down attitude of a plane). It can also reset itself after a pilot intervenes (this could potentially explain the repeated ups and downs from the doomed flights). The MCAS system read information from two sensors. If one sensor had faulty info or if the sensors reported different info, the system defaulted to one sensor. This does not follow fail-safe guidelines (the system should instead warn the pilots and shut off, if data readings are different, rather than just read one sensor, since that sensor could be incorrect).

There have been minimal responses to these allegations, as Boeing and the FAA cite being busy on the crash investigations. If this info is at all true, it suggests that the FAA processes are at best, outdated, and at worst, irrelevant and possibly affected by Boeing oversight, which would defeat the purposes of a checks and balances system.

Boeing has issued an update for all 737 MAX planes involving the MCAS system. It will include less aggressive interaction from MCAS, the ability to read from multiple sensors, and more complete override ability from pilots. Boeing will also update flight and training manuals. The legal side of these crashes will include justification from Boeing as to why they programmed the system the way they did to begin with, and justification from the FAA on how they determined it was safe or not.


Facts And Speculation on the 737 MAX Situation

What are the facts and what is speculation on the 737 MAX situation?

Air Canada Boeing 737 MAX 8 landing at London Heathrow International Airport LHR EGLL with nice blue sky weather. The Boeing 737 MAX8 aircraft has 2X LEAP engines and is the newest variant of the Boeing 737 series, Boeing 737-800. Air Canada AC is a Star Alliance member and connects London, England UK to the Canadian cities Calgary, Edmonton, Halifax, Montréal Trudeau, Ottawa, St. John's, Toronto Pearson, Vancouver. (Photo by Nicolas Economou/NurPhoto via Getty Images)

A brief history of the 737:

The short-range, narrow-body jet was planned in 1964 to be a smaller model in Boeing’s lineup, which at the time included the mid-market 727 and longer range 707 jet (the wide-body 747 would debut in 1969 to replace the 707, and the 757 and 767 models came out in the 1980s). The 737-100 made its first flight in 1967 and the lengthened 737-200 entered service in 1968 (these two models comprised the original 737 series). In the 1980s Boeing launched the longer 737-300, −400, and −500 variants (referred to as 737 Classic series). The 1990s brought the improved 737-600, -700, -800, and -900 versions (referred to as the 737 Next Generation or NG series). In 2017, the 737-7, -8 and -9 versions (referred to as the MAX series) debuted, and just under 400 have been built and delivered to customers.

Each refresh and generation of 737 brought more seating and cargo capacity, increased range and efficiency, and improved interiors and technology.

It’s relevant to point out that the 737 is now a much larger and longer-range plane than the original design called for. What was once a 100-seat plane with a range of 2,000 miles can now hold more than 200 people and fly twice as far. Because it’s still the same airframe, albeit heavily improved over the years, there are some design restrictions which are potentially noteworthy in the face of the recent 737 MAX incidents.

The 737 is low to the ground (originally built this way to facilitate servicing at the smaller airports the 737 was designed to fly in and out of, and because of the smaller engines on the original models). Therefore, the plane has short landing gear, which dictates the size of the engines that fit under the wing. Raising the height would require larger landing gear, which was deemed too expensive to re-engineer into the frame on later models; therefore, engine size is still restricted, even on the MAX. The more powerful & more efficient 737 MAX engines are larger than on the 737 NG models, which, in lieu of raising the plane, required the engines to be mounted higher and more forward on the wing than previous engines. This changed the center of gravity of the 737 MAX models compared to the NG, which in turn, required a change to the software that balances the plane in flight. This led to the MCAS system on MAX models.

Now let’s talk briefly about MCAS:

In flight, a stall occurs when the plane loses sufficient speed, and therefore airflow over the wings. Without the correct airflow over the wings, lift is reduced, and the plane would begin to drop. Pushing the nose down increases speed, and therefore airflow over the wings, and helps to avoid the stall. MCAS (Maneuvering Characteristics Augmentation System) software uses multiple sensors to determine when a plane may be stalling, and it could push the nose down to avoid a stall. Boeing says it can ONLY do this in certain extreme situations (i.e. it can’t push the nose down in regular flight, such as while taking off normally).

MCAS is new to the 737 MAX; the software was not on previous 737 generations

The FAA does not consider the 737 MAX a “new” aircraft, merely an “updated” version of the 737. This consideration means that less pilot training is required on MAX versions compared to a “new” aircraft. Airlines and manufacturers like this because it saves time and money. However, this does NOT mean that pilots weren’t trained, or that they did not know about MCAS.

Infamous accidents in modern aviation relating to stalls:

In 2009, Air France Flight 449, an Airbus A330 flying from Rio to Paris, encountered a storm with turbulence over the Atlantic. At the same time, the pitot tubes (which measure airspeed), froze over due to an icing condition in the storm. With the tubes frozen, the autopilot could not receive correct speed info, and disengaged. The pilots took manual control of the plane, as is procedure. The pilots took too long to figure out that they were entering a stall, and never recovered. The crash killed everyone on board, and the final investigation blamed poor pilot training, since all the issues were recoverable (there are procedures for turbulence, incorrect airspeed indications, and stall recovery, which are not uncommon occurrences in flight).

In 2014, Air Asia Flight 8501, an Airbus A320 flying from Indonesia to Singapore, encountered turbulence. Due to improper maintenance practices, a sensor for the rudder was never fixed months before the flight (sensors kept alerting the cockpit that it was not functioning). On this particular flight and during some weather issues, the pilots reset a circuit breaker to stop the rudder alert from sounding. Resetting the breakers disengaged the autopilot, leaving the pilots to manually fly the plane. Similar to the AF 449 situation, they entered a stall due to improperly reading cockpit information and were unable to recover. The final investigation blamed poor maintenance and lack of pilot training.

Simulations were done and both of these incidents were shown to be “recoverable” given the same parameters of the flights. A stall may sound tragic to the average person, but it’s something pilots train for from early in their careers and practice regularly. While poor maintenance and training made these particular occurrences fatal, a stall is not necessarily deadly. These accidents did show that many airlines have less than stellar maintenance and training programs.

Facts about Lion Air 610:

Lion Air Flight 610 was a 737 MAX 8 flying from Jakarta, Indonesia to Pangkal Pinang, Indonesia.

While the black box and flight data recorder have been recovered, they have NOT been fully analyzed, therefore most of what happened is still speculation.

The news, which is not an authority nor part of any investigative body, is saying that the computers on the 737 MAX 8 were sensing a stall, and therefore pushed the nose down, while the pilots were trying to pull the nose up.

Data DOES show that the plane pitched up and down many times before crashing. We DO NOT know why though.

We DO NOT know if the computers and/or MCAS were operating properly or not. If they were not functioning properly but everything else was, this would be a design issue. A full analysis will eventually tell us this.

We DO NOT know if the systems were operating properly but were being fed the wrong information by broken or inoperable sensors (i.e. if the computer was being told by sensors that the plane was stalling, it would be correct to pitch the nose down to recover).

We DO know that the SAME behavior happened on the same plane the night before Lion Air 610 (the aircraft was flying Bali to Jakarta), but we DO NOT know why. That flight pitched up and down many times, but pilots recovered and landed safely. The Lion Air 610 flight crew was aware that this had happened on the previous flight.

We DO know that in Bali, right before the Bali to Jakarta flight, the AoA sensors (Angle of Attack – simplified as sensors determining if the plane is nose up or down) were replaced on the plane due to previous pilots noting incorrect data. When the plane landed in Jakarta from Bali, the pilots noted the data was still not correct from the sensors that were just replaced before their flight.

From the Indonesian authorities (KNKT):

The Aircraft Flight Maintenance Log recorded that several problems occurred related to airspeed and altitude flag appeared on the Primary Flight Display three times, SPEED TRIM FAIL light illumination and MACH TRIM FAIL light illumination two times and Indicated Airspeed and Altitude Disagree shown on the flight Denpasar to Jakarta the day before the accident flight.

The KNKT released two safety recommendations to Lion Air stating the aircraft was not airworthy on the flight from Bali to Jakarta, and the flight should not have continued to Jakarta.

Refer to the CASR Part 91.7 Civil Aircraft Airworthiness and the Operation Manual part A subchapter 1.4.2, the pilot in command shall discontinue the flight when un-airworthy mechanical, electrical, or structural conditions occur. The flight from Denpasar to Jakarta experienced stick shaker activation during the takeoff rotation and remained active throughout the flight. This condition is considered as un-airworthy condition and the flight shall not be continued.

We DO NOT have the final results or responses on why this was not fixed or what maintenance did or did not do on the ground after the plane touched down the evening before Lion Air 610.

To summarize so far:

MCAS is a new system for the 737; it was meant to help pilots control the plane in certain extreme situations

There is a lot of speculation on the amount of control MCAS has on the plane, and whether or not pilots were made aware of its characteristics, and if they were trained properly

There were previous documented issues with equipment on the plane used for Lion Air 610. These were not resolved on earlier flights nor in time for Lion Air 610. It is possible that these broken sensors could have fed incorrect info to the computers and pilots. This would be a maintenance issue, not a design issue

Authorities recommended that the plane used for Lion Air 610 was not airworthy

Boeing and MCAS:

There is controversy around whether the operating manuals of the 737 MAX included details on the MCAS system. Some parties are claiming that it is NOT included in the manuals and that pilots were unaware of what the system could do, therefore potentially could not recover the plane from any actions the computer initiated.

Boeing is claiming that the 737 MAX is safe to fly, and that MCAS is detailed in manuals and pilots are aware of its operation. It is also saying that pilots, with proper training, should have knowledge of how to recover from a stall, regardless of how the stall occurs.

US pilots have confirmed that they were trained on MCAS, and they do not feel that the 737 MAX is unsafe. The rest of the world has grounded the planes until more information is available on what caused the crashes.

Lion Air is blaming Boeing for not disclosing MCAS operations; without MCAS info, it couldn’t prepare its pilots properly.

On March 12th, 2019 Boeing reported in a release:

For the past several months and in the aftermath of Lion Air Flight 610, Boeing has been developing a flight control software enhancement for the 737 MAX, designed to make an already safe aircraft even safer. This includes updates to the Maneuvering Characteristics Augmentation System (MCAS) flight control law, pilot displays, operation manuals and crew training. The enhanced flight control law incorporates angle of attack (AOA) inputs, limits stabilizer trim commands in response to an erroneous angle of attack reading and provides a limit to the stabilizer command in order to retain elevator authority.

From the FAA:

The FAA says it anticipates mandating this software enhancement with an Airworthiness Directive (AD) no later than April. We have worked with the FAA in development of this software enhancement. It is important to note that the FAA is not mandating any further action at this time, and the required actions in AD2018-23.5 continue to be appropriate.

A pitch augmentation control law (MCAS) was implemented on the 737 MAX to improve aircraft handling characteristics and decrease pitch-up tendency at elevated angles of attack. It was put through flight testing as part of the certification process prior to the airplane entering service. MCAS does not control the airplane in normal flight; it improves the behavior of the airplane in a non-normal part of the operating envelope.

Boeing’s 737 MAX Flight Crew Operations Manual (FCOM) already outlines an existing procedure to safely handle the unlikely event of erroneous data coming from an angle of attack (AOA) sensor. The pilot will always be able to override the flight control law using electric trim or manual trim. In addition, it can be controlled through the use of the existing runaway stabilizer procedure as reinforced in the Operations Manual Bulletin (OMB) issued on Nov. 6, 2018.

As of Wednesday, March 14th, American Airlines is flying 24 MAX-8s and has already installed updated software that more clearly warns pilots of the engagement of MCAS. Southwest, which flies 34 of the jets, is in the process of making that change.

From other pilots:

There is a confidential database that pilots can anonymously contribute to that’s not run by the FAA or the airlines. They can submit things that go right and wrong on an aircraft, or can voice opinions and complaints on operations, airlines, equipment, etc. Digging through this database, some reporters have found MCAS entries from 737 MAX pilots.

There are 5 entries related to MCAS, out of thousands of total entries. These 5 pilots all reference MCAS pitching the nose down right after takeoff and right after autopilot was turned on, and for an un-apparent reason. The pilot flying immediately switched off autopilot and pulled the nose up and there were no more issues.

One of the 5 entries references MCAS is more detail. Pilots were informed about the system, but the manuals did NOT reference the parameters that it would activate. It is meant to alleviate a stall only in extreme angles and situations, and the exact metrics for when these occur are not in Boeing’s pilot information guides.

These entries suggest that pilots knew that the MAX aircraft had MCAS but found it odd that Boeing did not include every single detail on the functionality of the system. However, none of the pilots were worried or felt unsafe, since training covered stall recovery. After the incidents, the pilots did look up the MCAS details and parameters, which are available from Boeing but only in certain deeper-dive material, and were confused as to why it activated in the first place, since in normal takeoffs the plane never fell into the realm of where MCAS should step in.

Overall summary and questions:

We will not know all the facts until the authorities from all involved countries and parties release their final reports. It’s important to not jump to conclusions, and to realize that aircraft and aircraft investigations are overwhelming complex.

There are big questions:

Did Boeing provide enough information on MCAS to sufficiently prepare pilots for flight operations?

Is MCAS technology safe or is its logic and operations flawed?

Did airlines, who are responsible for training pilots, prepare them properly?

What were the maintenance issues on Lion Air 610, why weren’t they properly dealt with, and what are the implications of improper maintenance on MCAS and flight operations?

If the same thing happened the night before Lion Air 610, and the pilots recovered, why weren’t the pilots able to recover the next morning?

Have other pilots had issues with the 737 MAX, and if so, where is this documented and what are authorities doing about it?

Boeing is updating MCAS and its manuals; will some see this as an admission of guilt by the manufacturer? If so, then is the FAA also guilty, as the governing body that determined the 737 was airworthy?

Boeing Statement on 737 MAX Software Enhancement

Boeing Statement on 737 MAX Software Enhancement

A copy of the press release from Boeing on the recent 737 MAX crashes :

March 11, 2019 – The Boeing Company is deeply saddened by the loss of Lion Air Flight 610, which has weighed heavily on the entire Boeing team, and we extend our heartfelt condolences and sympathies to the families and loved ones of those onboard.

Safety is a core value for everyone at Boeing and the safety of our airplanes, our customers’ passengers and their crews is always our top priority. The 737 MAX is a safe airplane that was designed, built and supported by our skilled employees who approach their work with the utmost integrity.

For the past several months and in the aftermath of Lion Air Flight 610, Boeing has been developing a flight control software enhancement for the 737 MAX, designed to make an already safe aircraft even safer. This includes updates to the Maneuvering Characteristics Augmentation System (MCAS) flight control law, pilot displays, operation manuals and crew training. The enhanced flight control law incorporates angle of attack (AOA) inputs, limits stabilizer trim commands in response to an erroneous angle of attack reading, and provides a limit to the stabilizer command in order to retain elevator authority.

Boeing has been working closely with the Federal Aviation Administration (FAA) on development, planning and certification of the software enhancement, and it will be deployed across the 737 MAX fleet in the coming weeks. The update also incorporates feedback received from our customers.

The FAA says it anticipates mandating this software enhancement with an Airworthiness Directive (AD) no later than April. We have worked with the FAA in development of this software enhancement.

It is important to note that the FAA is not mandating any further action at this time, and the required actions in AD2018-23.5 continue to be appropriate.

A pitch augmentation control law (MCAS) was implemented on the 737 MAX to improve aircraft handling characteristics and decrease pitch-up tendency at elevated angles of attack. It was put through flight testing as part of the certification process prior to the airplane entering service. MCAS does not control the airplane in normal flight; it improves the behavior of the airplane in a non-normal part of the operating envelope.

Boeing’s 737 MAX Flight Crew Operations Manual (FCOM) already outlines an existing procedure to safely handle the unlikely event of erroneous data coming from an angle of attack (AOA) sensor. The pilot will always be able to override the flight control law using electric trim or manual trim. In addition, it can be controlled through the use of the existing runaway stabilizer procedure as reinforced in the Operations Manual Bulletin (OMB) issued on Nov. 6, 2018.

Additionally, we would like to express our deepest condolences to those who lost loved ones on Ethiopian Airlines Flight 302. A Boeing technical team is at the crash site to provide technical assistance under the direction of the Ethiopia Accident Investigation Bureau and U.S. National Transportation Safety Board. It is still early in the investigation, as we seek to understand the cause of the accident.

Ethiopian Airlines 302 has a lot in common with Lion Air 610

Today, a Boeing 737 MAX 8 aircraft operating Ethiopian Airways Flight 302 crashed after takeoff, en route to Nairobi. A few months ago, Lion Air Flight 610, also a Boeing 737 MAX 8, crashed after takeoff. There were no survivors in either incident.

RENTON, WA - JANUARY 29: A Boeing 737 MAX 8 airliner lifts off for its first flight on January 29, 2016 in Renton, State. The 737 MAX is the newest of Boeing's most popular airliner featuring more futel efficient engines and redesigned wings. (Photo by Stephen Brashear/Getty Images)
RENTON, WA – JANUARY 29: A Boeing 737 MAX 8 airliner lifts off for its first flight on January 29, 2016 in Renton, State. The 737 MAX is the newest of Boeing’s most popular airliner featuring more futel efficient engines and redesigned wings. (Photo by Stephen Brashear/Getty Images)

The 737 MAX is an update on the long-running 737 model; the MAX was released in 2017 and is used in many airlines, including American, Southwest, and United, and has future orders for more than 5,000 units. The Boeing 737 is the best selling jet airliner in history and is used throughout the world. The MAX editions bring enhanced engines for longer range and better efficiency, cabin updates, improved electronics and technology, and more seating on some versions.

Similarities between the two crashes :

  • Both used very new Boeing 737 MAX 8 aircraft
  • Both crashes happened within a few minutes after takeoff
  • From preliminary data, it looks like both pilots had trouble maintaining altitude in the climb-out
  • Weather was not a factor in either incident

The Lion Air investigation has not concluded, but the focus remains on Boeing’s MCAS system, which has a feature that points the plane’s nose down if sensors determine a stall is imminent. On a flight the day before Lion Air 610 (using the same aircraft), pilots reported difficulty controlling the aircraft. Data is showing that the plane’s electronics, detecting a stall, kept pushing the nose down to prevent it, while the pilots would then try to pull back up. Something similar was happening on Lion Air 610 the next day. What is not confirmed is whether this was a fault of the MCAS computer, or a faulty sensor elsewhere that could have been feeding pilots incorrect info, thereby causing them to take incorrect action. Lion Air is claiming that Boeing did not advise airlines and pilots of this new MCAS functionality while Boeing is saying that this is not the case.

When the investigation is complete, this could potentially be bad for Boeing; however it could also be airlines provided lack of training on the system and pilot error is the cause. We could also find out that a plane was not maintained properly, which would fall on the airline, not Boeing. Having two of it’s aircraft crash within months of each other is not good for Boeing, regardless of the investigation’s outcome.

History shows us that Boeing and Airbus are not perfect; mistakes have been made in engineering, design, and execution of even the most popular airliners. However, the 737 has a very reliable history over many decades. We have also seen in recent years, as lower cost and non first-tier airlines expand, a lack of training (AirAsia 1501 in 2014). As a counter-point, we have also seen lack of pilot training as a cause in major airlines as well (Air France 447 in 2009).

Will these potentially related accidents turn out to be the fault of Boeing? Or will the authorities determine that pilot error, improper training procedures, or faulty maintenance be the cause of these 737 MAX disasters?




JFK to MEX on AeroMexico’s 787-8 Dreamliner in Business Class


January 2019

Status : Delta Diamond Medallion

MQM 6,270
MQD 1,632
SkyMiles 13,376
Price $406
Cost/Mile $.065
Delta Reserve Card 812 SkyMiles


There was a lot of noise on social media and deal sites promoting Aeromexico’s business class round-trip fares between New York City and Mexico City. These deals were a solid value at around $600, which is about half the normal price. Aeromexico flies a 787 Dreamliner once a day in each direction on this route, so I used ITA Matrix to find the round-trip flights in business-class on this particular plane (They have other flights using 737s and Delta’s 757s). Surprisingly, the pricing was coming up as $406! (Note : you had to buy through Orbitz, this price was NOT coming up on nor

This is a fantastic deal for round-trip business class to Mexico City. As I’m trying to maintain Diamond Status with Delta in 2020, I credited the miles to my SkyMiles account. The most challenging part of getting Diamond Status is attaining $15,000 MQDs (Medallion Qualification Dollars); Delta wants you to spend real money on tickets, and has increased the Amex Credit Card spend waiver to $250,000, which is unattainable for me (previously $25,000 in Amex spend got you the MQD waiver).

Delta’s Tier 1 partners, which Aeromexico is one of, accumulate mileage differently than a regular Delta flight. For MQDs, use the distance flown and a multiplier, which for most business class fares is 40%. So for Aeromexico flights, bought through Aeromexico and operated on Aeromexico metal, what you actually spend in dollars doesn’t matter for MQDs. For a round-trip flight to Mexico City, the distance is 4,080 miles; multiply that by 40% to get 1,632 MQDs. (Note : MQMs and SkyMiles also work like this; different fare classes have different multipliers).



Aeromexico uses Terminal 4 at JFK. The huge terminal is where nearly all Delta flights depart and arrive; a few international carriers utilize this building also. In 2018, Delta increased its investment in Aeromexico, and the infiltration of Delta’s operational know-how is beginning to be visible on the Mexican carrier. The boarding process used to be chaotic; now it’s just slightly unorganized. Compared to my last flight on AM to Mexico City (in early 2018), there was more signage for queing up and slightly clearer boarding alerts. Still, the airline should make more announcements and utilize the overhead screens to show which zone is being called.

The flight wasn’t full, and the terminal itself wasn’t busy. This is probably more related to winter weather and the government shutdown than to Aeromexico or Delta. I’ve seen T4 absolutely packed; the crowding also varies if you have any of the international flights on A380s coming in, which flood the terminal.I have both TSA PreCheck and CLEAR, and there was no line for either. I breezed through security and headed for the T4 Delta SkyClub, which you can access as a SkyTeam Elite member (Gold, Platinum, or Diamond Status) on a coach ticket or with any SkyTeam business class ticket. You can also access this club with the Delta Reserve Amex card. Delta has slowly been improving this club with better food options, upgraded seating, and additional features. Today, there were serving complimentary Pierre Herme macarons, which were really good. Never say no to a macaron.

As a business class passenger, I boarded with Zone 1. There was a friendly flight attendant at the cabin door helping passengers find their seats. My seat, 4A, was stocked with headphones, a blanket, and a pillow. All of these items were upgraded since my last flight a year ago (same route, same aircraft), suggesting that AM is investing in their product. The 787-8 uses a 2-2-2 layout with lie-flat seats; unfortunately, not everyone has aisle access. AM also has 787-9 aircraft, which have newer seats with a reverse herringbone layout, which gives each passenger aisle access and more privacy.


As the cabin filled up (every seat in business class was eventually taken), flight attendants came by with a choice of champagne (Jacques Brut, pretty good!), orange juice, or water. This service has been inconsistent on past flights. The cabin is still new and in great shape (as it should be on the recently acquired Dreamliners), and was well maintained and clean. However, the outside of the window was really scratched up, which made pictures difficult. One of the great features of the 787 are the electrochromic windows that darken with a button instead of with shade. And it’s Avgeek heaven to watch the Dreamliner’s composite wings flex up during takeoff (Fun Fact : the Dreamliner’s wings can flex up to 10 feet during takeoff and flight, and up to a max of 26 feet!).


If you haven’t flown a Dreamliner, definitely add it to your list. In addition to the windows, its quieter than most aircraft (my unofficial noise meter says the A350 and 747-8 are slightly quieter and the A380 is the quietest) and you get huge overhead bins, mood lighting, large bathrooms, a galley mini-bar (not on all airlines), and the more humid air that the composite structure allows. I’ve never come off these Dreamliners feeling like I’ve been flying for hours.

About 15 minutes after passing through 10,000 feet, flight attendants gave out menus and came by with a beverage cart. There was two dinner options, along with juices, one champagne, and six wine selections. The flight attendant referenced a sheet for everyone’s name, which has never happened on previous AM flights (nice touch!). They also passed out appetizers (fruit, cheese, and crackers). While it’s a nice business class feature, the crackers were in their original plastic bag – presentation could be better rather than cheese, 5 grapes, and crackers in plastic on a plate.About 15 minutes later they returned with drink refills and your meal selection. I selected the pasta over the fish. It came with a small salad, roll, a strange artichoke appetizer with cheese, and pasta with red sauce. Again, good service was let down by average taste and mediocre presentation. This was essentially the same meal you’d get on most international carriers in coach, but on a plate/tray instead of in the microwavable carton.


The flight attendants came around once more offering refills, which was an upgrade from the last few AM flights, where they disappeared immediately after dropping off meals.The trays were cleared about 15 mins after I finished, and then the cabin crew ceased to exist. This was pretty par for the course, although now it occurred later in the flight. I would’ve liked a snack service or additional drinks/water. They appeared before landing to collect garbage. On one AM flight in 2018, there was a snack bar set up in the galley; this was nowhere to be found on this flight.


A couple of other minor observations for this flight :

  • The IFE was similar to the new screens on Delta’s planes, and feature a decent selection, good resolution, and quick touch responses. However the remote didn’t work at all, and was located near the hip, so moving around in the seat made it pop out of the receptacle often
  • The Delta App synced with the outbound flight but not the return (I guess a step up from last year, where AM flights never appeared in the Delta App)
  • The seats made a decent amount of whirring noise when powering up or down – this is somewhat acceptable on older planes like the 767, but odd for a new Dreamliner
  • Mexico City Terminal 1 is a mess; checking in to fly back to JFK even with a paid business class ticket is awful – long lines and minimal service with no kiosks

Flying back to JFK on the same 787-8 produced nearly the exact same service with the same meal options. I’m glad to see Aeromexico improving its consistency; in the new year, they will hopefully improve the quality of business class as well as some of their operations, especially on the Mexico City side.


The Dreamliner is a great plane, and customers as well as Avgeeks seem to love it. If you’re considering Aeromexico’s Dreamliner, it’s worth checking for the newer seats on the 787-9. My experience with them last year was significantly better than the 2-2-2 configuration on the 787-8.Overall, this was a good flight on an improving airline, and an excellent value.

Delta’s Inaugural Airbus A220 Flight

The Airbus A220 is the newest regional jet to be introduced to the commercial market. The 100-160 seat plane was introduced in 2016 with launch customer Swiss Air, but Delta is the first US airline to purchase it. I had the opportunity to fly the maiden flight on Delta’s A220-100 in February 2019.

Previously launched as the Bombardier CS-Series, Airbus purchased the program from the Canadian manufacturer, and renamed the jets A220. There are -100 and -300 iterations, and Delta has ordered 90 planes, between the two models. These short to medium range jets are meant as a more modern and efficient replacement for an airline’s older A319, 737 Classic, and Embraer models. In addition to the latest technology and composite materials available, they feature a wider cabin than most regional jets, larger windows, and more overhead bin space. Airbus claims an overall 15% lower seat-mile cost, 20% lower fuel burn, a 25% reduction in maintenance costs, as well as a four-fold reduction in the noise level compared to existing competing aircraft.

Delta’s inaugural Airbus A220 flight was on February 7th, flying from Laguardia (LGA) to Boston (BOS). An hour later, another Delta A220 would kick off the LGA to Dallas (DFW) route. These first flights had been moved back a week or so due to the government shutdown affecting FAA certification paperwork.

The day before the inaugural flight, I received an email invite to join the “First Flyers Club” from Delta. It didn’t offer a lot of details but invited me to arrive early for a brief introduction and celebration of the new aircraft. I was planning to do this anyway, since I had read other people’s reviews when they flew on a new aircraft, but was excited nonetheless that Delta was promoting the event.


When I arrived at LGA at 430am, a little more than an hour before departure, the security lines and most of the airport were empty. Walking to the gate, there was a lot going on – breakfast was being set up, and there was a podium and step and repeat near the boarding desk. Amidst the Delta and LGA executives, the passengers seemed to be about 90% aviation enthusiasts here for the inaugural flight. The remaining passengers looked like they needed to get to Boston and were surprised/confused by the celebration.


Right before boarding, two guest speakers talked about the plane and equipment, and there were photos with the crew and pilots. Delta employees were handing out swag and it seemed everyone was really excited about the new plane. Once we boarded, there were placards and flight pins on every seat, which was a nice touch.


The Airbus was obviously brand new, as this was it’s first revenue flight, despite undergoing pilot and crew testing for a few months. The interior and aisle and ceiling height felt like a A320 or 737, not like a cramped CRJ or Embraer. While seating was 2-3, which is one more than those jets but one less than the usual 3-3 on the A320 or 737, the feel was that of a largier, airier plane. No ducking or bumping into overhead bins.



The windows were larger than most narrowbody planes but these are not definitely not the huge electroluminescent windows from the Dreamliner. Still, it’s nice to be able to see more and not have to move your head so much. The seats in coach were wider than any narrowbody I had ever been on; even though the plane will be used for shorter flights, it’s nice not to feel squished in. Every seat featured Delta’s new IFE system, which is wireless and doesn’t need any equipment under the seat – more footroom for all!. The screen operation and size is similar to the new IFEs on current refurbished Delta aircraft. One nice touch was the airshow, which included a pilot’s cockpit & gauge view, which was really cool.


The most noticeable thing about the plane, other than being brand new, was how quiet it was. Takeoff was QUIET – rivaling the A380. You feel a push and you feel speed increasing, but there is next to no takeoff roar. I was sitting near some guys from Pratt and Whitney (the engine manufacturer) and they cheered after takeoff – along with nearly everyone commenting on how quiet the plane was. Once flying, it’s a quiet ride, but not as notably silent as a big, new jet. Quieter than any regional or mid-range plane for sure.


Landing in Boston amidst cheering, most people deplaned but a lot of passengers stayed to talk to the pilots and crew, who were all really friendly, helpful, and informative. It seemed everyone had a great time and was really excited about the new A220. I flew back to LGA in business instead of coach, just to check out the front cabin. The larger seats feature a new water bottle storage area, and are a clean, attractive design. All seats in all cabins have outlets and USB ports, which is unlike the CRJ and Embraer aircraft.


The new A220 will be a great addition to regional flying – it’s a much improved aircraft than what is currently flying. There isn’t one frequent flyer who is excited when a CRJ is parked at their gate – now, we can look forward to a much better short range flying experience.

The Most Influential Air Crashes that Changed Modern Aviation

Despite people’s fascination with planes, travel, and flight, there were many accidents and deaths in the history of aviation. Some of these were a distant memory, while others were gruesome enough to stick in the minds of people and the media and to make a lasting impression. While it’s unfortunate that sometimes it took crashes and human lives to make a significant change in the industry, one can view these as learning experiences that forced commercial aviation to become even safer. Here are the incidents, in chronological order, that took place that had the largest impact on modern aviation.

1954 : BOAC Flight 781

Summary : BOAC 781 was a de Havilland Comet passenger jet flying from Rome to London that crashed into the sea off the Italian coast after suffering an explosive decompression. All 35 people on board were killed. The loss was the second in a series of three fatal accidents over twelve months caused by structural failures The first was BOAC Flight 783 near Calcutta, India, in May 1953. The investigation found that, after encountering a storm, stress on the frame caused it to break apart. The third was South African Airways Flight 201 in April 1954, which was also eventually determined to be explosive decompression due to structural failure.

Findings : The ruptured lungs of deceased passengers pulled from the ocean were an indicator that the cabin depressurized – the sudden decrease would cause the lungs to expand until they broke. Investigators were able to conclude that the crash had been due to failure of the pressurized cabin at a forward window. The failure was a result of metal fatigue caused by the repeated pressurisation and depressurisation of the aircraft.

Changes : The crash of Flight 781 caused a revision in the estimates of the safety requirements of airliner pressure cabins and materials. In addition, it was discovered that the stresses around cabin apertures were considerably higher than anticipated, especially around sharp-cornered doors and windows. As a result, future jet airliners would feature windows with rounded corners which reduced stress.

BOAC 781

Related & Notable : Aloha Flight 143
As Aloha 243, a 19-year-old Boeing 737 on a short hop from Hilo, Hawaii, to Honolulu in 1988, leveled off at cruising altitude, a large section of its fuselage blew off, sucking out a flight attendant (somehow the only fatality) and leaving many passengers flying in open air. Miraculously, the plane held together long enough for the pilots to land. The NTSB blamed a combination of corrosion and fatigue damage, the result of repeated pressurization cycles during the plane’s ~89,000 flights. The FAA tightened inspection and maintenance requirements for aircraft.

aloha 143 jpg


1956 : TWA Flight 2 & United Airlines Flight 718
Collision Avoidance and Improved ATC

Summary : A United Airlines Douglas DC-7 struck a Trans World Airlines Lockheed Super Constellation over the Grand Canyon. All 128 passengers and crew on board both flights perished.

Findings : The TWA Constellation, flying from Los Angeles to Kansas City, was in uncontrolled airspace near Colorado (out of range of air controllers, normal for the times). The United DC-7, flying Los Angeles to Chicago, also entered this uncontrolled space. With requests to change altitude due to weather unable to be both communicated to ATC and to other aircraft, separation remained difficult. The two planes collided at a 25 degree angle, resulting in mangled fuselages and explosive decompressions, and then plummeted into the canyon and exploded.

Changes : The accident resulted in a huge upgrade of the air traffic control system. Shortly after, the Federal Aviation Agency was created to oversee air safety.

Grand Canyon Crash

Related & Notable : PSA Flight 182 and Aeromexico Flight 498
Significant improvements to the ATC system would be implemented after two similar incidents. In 1978, a private plane flew into the landing path of San Diego Int’l Airport, crashing into PSA 182, a Boeing 727 just a few minutes from touching down. 144 people in the planes and on the ground were killed. In 1986, another private plane flew into the LAX control area, striking AM 498, a McDonnell Douglas DC-9, and killing 86 people. The FAA subsequently required all aircraft to use transponders (electronic devices that broadcast position and altitude). Airliners were also required to utilize the TCAS collision-avoidance system, which detects potential collisions with other planes and advises pilots to climb or dive to avoid each other.

PSA crash September 25, 1978. Photograph taken by Hans Wendt who has granted U-T permission to reuse (as of September 1999). U-T use only, NO SALES

1978 : United Airlines Flight 173
Cockpit / CRM

Summary : United 173, a McDonnell Douglas DC-8, flying New York to Portland, Oregon with 189 people on board, circled near the airport for an hour as the crew tried to sort out a landing gear problem. Although warned of the diminishing fuel supply, the captain waited too long to begin his final approach. The DC-8 ran out of fuel and crashed in a suburb, killing 10.

Findings : With the crew disorganized and dealing with a landing gear issue (it was actually lowered but was not indicating as such), the three men in the cockpit were not communicating nor working together to solve the various issues.

Changes : Airlines revamped their cockpit training procedures around the then-somewhat-new concept of Cockpit Resource Management (CRM). Previously, the captain was considered “god” in the cockpit, while CRM emphasized teamwork and communication among the crew, and has since become the industry standard.

United 173

Related & Notable : Eastern Airlines Flight 401
In 1972, Eastern Airlines 401, flying from New York to Miami, crashed in a swamp in Florida just 18 miles from the runway. The Lockheed L-1011 pilots were distracted with a landing gear light, failing to notice that the autopilot disconnected and that the plane was losing altitude. The crash killed 101 people, but 75 survived. This flight introduced the concept of CRM, while the 1978 United crash made it widespread.


1979 : American Airlines Flight 191
Maintenance procedures

Summary : American Airlines 191, a McDonnell Douglas DC-10, was taking off from Chicago en route to Los Angeles. Upon lifting off, the left engine separated from the wing, ripping out hydraulic lines with it. The plane continued gaining altitude briefly, but rolled on its side and crashed near the end of the runway, killing 273 people.

Findings : This disaster was particularly gruesome since many people were watching, both from the airport itself and on the ground nearby (The plane also unusually featured in-cabin cameras, so the passengers are assumed to have watched themselves crash). Investigators traced the issue to faulty maintenance on the part of American Airlines – fractures stemming from improper procedures led to the engine falling off. McDonnell Douglas was faulted for various design issues on the DC-10 which had failed after the engine ripped off, possibly preventing the pilots from recovering from an “engine-out” incident.

Changes : With so many people seeing the crash, as well as photographs published by the media, American 191 was a publicity nightmare for both the airline and McDonnell Douglas. Maintenance procedures and audits were overhauled, and American paid hefty fines. Various instruments and controls were redesigned on all airplanes. The DC-10, with numerous crashes over the next few years, was mainly relegated to cargo service.

american 191

Related & Notable : Alaska Airlines Flight 261
In 2000, Alaska 261, a McDonnell Douglas MD-83, was flying from Puerto Vallarta to Seattle, with a stop in San Francisco. Over the Pacific, the plane loss pitch control and crashed into the ocean off LA, killing all 88 aboard. The cause was found to be improper maintenance of the jackscrew assembly, which controlled the rear stabilizers and prevented the plane from climbing or descending.

alaska 261


1983 Air Canada Flight 797
Fire protection, emergency requirements & procedures

Summary : Air Canada 797, a McDonnell Douglas DC-9 en route from Dallas to Toronto, began emanating smoke from the lavatory. The plane began an emergency descent into Cincinnati, where the pilot landed even though the cockpit was clouded with smoke. Shortly after, the doors and emergency exits were opened but the cabin erupted in a flash fire before everyone could get out. Of the 46 people aboard, 23 died.

Findings : A fire of unknown origin caused smoke in the cabin and eventually burned through some electrical wires, causing loss of power in some parts of the plane and cockpit, including the controls for the rear stabilizers. Blame partially fell on the crew for delaying to advise the captain and correct the smoke issue therefore taking longer to land.

Changes : The FAA mandated that aircraft lavatories be equipped with smoke detectors and automatic fire extinguishers, all jetliners had to be retrofitted with fire-resistant seat cushions and interior materials, and that floor lighting had to lead passengers to exits. Also, regulations regarding evacuation procedures were updated.


Related and Notable : Valujet Flight 592
In 1996, ValuJet 592, a McDonnell Douglas DC-9 flying Miami to Atlanta, crashed in the swamp after takeoff due to improperly stored cargo causing a fire in the hold. All 110 passengers died. The fire was caused by chemical oxygen generators that had been illegally packaged and shipped. The FAA made smoke detectors and automatic fire extinguishers in the cargo holds mandatory and changed rules regarding carrying hazardous cargo.

Related and Notable : SwissAir Flight 111
In 1998, the pilots of SwissAir 111, a McDonnell Douglas MD-11 flying from New York to Geneva, smelled smoke in the cockpit and began descending towards Halifax, Nova Scotia. The electrical fire above the cockpit rapidly burned through the control wires, and the pilots, unable to fly the plane, crashed into the ocean. All 229 people aboard were killed. The fire was traced to the plane’s in-flight entertainment network which ignited flammable insulation. The FAA ordered the insulation replaced with fire-resistant upgrades and required changes in aircraft material (testing, inspection, and maintenance), electrical systems,and flight data electronics, as well as new checklists in fire-detection and training


1985 : Delta Flight 191
Microburst and downdraft detection

Summary : As Delta 191, a Lockheed L-1011, lined up for landing at Dallas/Fort Worth airport, a thunderstorm appeared near the runway. At around 800ft high, the airliner encountered a microburst wind shear—a strong downdraft and abrupt shift in the wind. Losing altitude rapidly, the L-1011 hit the ground about a mile short of the runway and bounced across a highway, hitting vehicles and utility poles, and then crashed into two water tanks. 134 of 163 people onboard were killed.

Findings : The NTSB deemed the cause of the crash to be attributable to pilot error (deciding to fly through a thunderstorm), combined with extreme weather associated with microburst-induced wind shear. The bureau also determined that a lack of specific training, policies, and procedures for avoiding and escaping wind shear was a contributing factor.

Changes : The crash triggered a seven-year research effort involving the FAA and NASA, which led to improved training in addition to the on-board forward-looking radar wind-shear detectors that became standard equipment on airliners by the 1990’s.

delta 191

1989 : United Airlines Flight 232
Engine safety & maintenance

Summary : United 232 was en route from Denver to Chicago, when the engine in the tail of the McDonnell Douglas DC-10 suffered disk failure, severing the plane’s hydraulic lines and rendering the plane uncontrollable. The 296 people aboard experienced a flight from hell as the captain struggled to land with minimal controls. As it crashed on the runway, the DC-10 cartwheeled and caught fire. Somehow 185 survived (111 died).

Findings : The NTSB determined that the accident was caused by a failure to detect a crack in the engine fan disk that was traced back to the initial manufacture of the titanium alloy material.

Changes : The accident led the FAA to order modification to the DC-10’s hydraulic system (the aircraft was already being phased out by many airlines due to previous fatal crashes) and to require redundant safety systems in all aircraft. It also changed the way engine inspections and maintenance were performed. This was really the nail in the coffin for the DC-10, and eventually influenced Boeing’s purchase of McDonnell Douglas in the 1990s.

united 232 1


2014 : Malaysia Airlines Flight 370
Real-time flight tracking

Summary : Malaysia 370, a Boeing 777 carrying 239 people from Kuala Lumpur to Beijing, dropped off radar screens shortly after reaching cruising altitude. Locator pings from the engines to satellites, not generally used in normal aviation, have somewhat reliably shown the plane turning around and heading south into the Indian Ocean, the opposite direction from its destination.

Findings : The plane’s transponders were disabled, making the jet almost invisible as it changed course and headed south, where some experts believe it flew for up to seven hours before running out of fuel and crashing into the ocean. Years later, all we have as clues are a few parts that have washed up thousands of miles away. Theories range from rapid decompression to intentional sabotage from a crew member.

Changes : We wouldn’t still be looking for the plane if it had been equipped with real-time tracking. The International Civil Aviation Organization has ordered all airlines to install tracking equipment that will better locate planes. Aircraft manufacturers are also developing improved black boxes and recording devices.


Note : Terrorist attacks are not included. These incidents changed aviation in numerous ways, but this list is focused on changes from lessons learned in engineering and design, as well as human error. The 1988 Pan Am 103 “Lockerbie” disaster and the 911 attacks, for example, are not part of this article.

Note : Crashes involving the military are also not included here. Incidents such as the shooting of Malaysia Air 17 in 2014, Iran Air 655 in 1988, and Korean Air 007 in 1983, all of which had something to do with the military, are not on this list.