Boeing is as synonymous with commercial aviation as Bell is to helicopters. They invented quality systems (on which ISO-9000 is based). So, how is it that they appear to have lost the plot?

Part-I:  Tail wags Dog

To understand this tragic tale, we need to go right back to the beginning. So in this essay it will be done in several parts. Firstly to get a perspective through a brief history of the Boeing Company leading up to the Max’s production and then to analyse the elements of the scandal itself. It starts more than a century ago. The Boeing company’s origins in Seattle were not in aviation but in lumber and cabinet manufacture and owned by William E. Boeing.  

Replica of the first Boeing aircraft – the B&W Seaplane at the

Museum of Flight in Seattle

In the inter war years, Europe was the lead in aircraft development with the USA generally optimising those designs and their manufacture. The British Avro, Vickers and Handley Page medium-heavy bomber designs were thus optimised into the Boeing B-17 ‘Flying Fortress’ heavy bomber – actually an early Boeing technical disaster. Rather than through any incompetence, this was a factor of their technical enthusiasm in stretching the norms of aviation technology. The B-17 was the largest, the fastest, the highest flying and with the biggest payload in its class, far exceeding all the parameters of the military RFP to which it was the Boeing Company response. As such it was also technically, significantly more complicated. So it was that, during a display to the client, the prototype crashed due to elements of the  very long start-up checks being overlooked, killing the Boeing Chief Test Pilot and an Airforce General flying as a passenger in the Co-pilot’s seat. Not surprisingly, the first contract for 200 units was thus awarded to Douglas. The enduring result of that crash was the birth of the aircraft check-list. Not surprisingly, subsequent contracts went to Boeing and ultimately, more than 12,000 B-17 units were built.

As a factor of the War, Europeans continued to lead in aviation innovation and development.  The Brits developed the first jet engine (the Whittle in 1933) and the Germans with the first jet aircraft (Heinkle-178 in 1939) as well as rocketry (V-I in 1944). The first mass-production jet was the British Meteor bomber (March 1943). The first US jet was the Bell XP.59-A (1942) powered by a Whittle engines built under license by GE.  

Post-war, this led to the first jet Airliner (the British Comet-1952) but after a series of fatal accidents due to metal fatigue, it was grounded for a time while the root cause, square windows, were changed to the current oval design. This allowed the much later Boeing Jet Airliner (the iconic B.707-1957) to catch up and subsequently dominate the market. Bill Boeing, unfortunately, passed away shortly before its maiden flight, so he did not witness the fruits of a lifetime of innovation. But the Boeing Company never looked back, dominating world aviation for the next two generations although, once again stretching aviation limits, the very large B-747 (1969) did come within a whisper of bankrupting them.

Beauty and the Beast – an unhappy ending

A most significant event in Boeing’s subsequent history was the 1996 merger with it’s former rival Douglas – now McDonald-Douglas (MD). This was a function of a so-called ‘Last Supper’ in Reagan’s White House, where it was decreed that the dozen US aircraft manufactures should be reduced by half. Because the MD widebody iteration, the DC-10, was unsuccessful, MD was financially the weaker partner in the merger. Accordingly, Boeing was the lead with the merged entity assuming its name. However, within a couple of years, the junior partner had assumed control. This led to cultural changes within Boeing which are the likely root cause of its current technical problems.

Boeing began as a hobby-venture and it never lost that ethos. It was a family firm driven by technological excellence – in it, the engineers were king. The MD culture was one of corporate bean-counters with shareholder value rather than engineering excellence being the foremost core-value. Hence, post-merger, this prevented Boeing make the necessary investment to match the European technical innovation focused in the European government under-written Airbus designs. So at the turn of the century, when the state-of-the-art and highly efficient A320 family started to dominate the narrow-body market, with the A330 to 380 impacting the wide-body market, Boeing had to compete with 1960/1970s designs – the B737-series and B767-series respectively. Neither was a match for the state-of-the-art Airbus competition as the table below of wide-body performance shows.

In parallel, within the Boeing corporation, the gulf between engineering and management was similarly growing, exacerbated by the latter moving out of Seattle into new offices in Chicago in 2001. Whereas before in the Boeing family, management and marketing spent as much time chatting on the factory floor as in the office, after the move, the process was rare and formalized.  Over the years, production targets were consistently increased as were expected sales margins by decreasing production costs. This latter was, in large part, focused on manpower reductions, certification limitation strategies, reduced quality control (QC) and minimizing pilot conversions.  One measure of this parsimonious attitude was clearly evidenced in the QC process whereby the number of inspectors on the factory floor, according to a documentary by Rory Kennedy (Downfall – the case against  Boeing – 2021), was reduced from a score to just one per shift.  

Clearly knocking out more aircraft each week (up to a dozen) with less of everything, instilled an atmosphere of stress in the culture and practices on the factory floor and this is now evidenced in virtually every major Boeing program. In addition to the 737-Max saga, poor program management is evidenced in the 777-X being years behind schedule, 787 production being on temporary hold due to QC standards and certification issues, the USAF new generation (B767-based) KC-46 aerial Tanker’s experiencing a very messy and delayed acceptance into service and, in space, aa the Starliner spaceship’s hugely delayed first launch. The common cause would appear to be corporate penny-pinching, and this is a probable root cause of the most recent B737-Max outrage as Part-III will show.

Part-II: The King has no Clothes – how Boeing lost Market Hegemony

By any standard, the 737 is a very successful mid-market aircraft with more than 10 thousand units thus far built over its 50-year life-span. During this time-frame, by incremental stretches, the 737-series range and payload have been more than doubled. In the widebody sector, the B747 Jumbo Boeing dominated the trans-oceanic routes. Overland, the only serious competition to its B767 wide-bodies were other US iterations such as the MD DC-10 and Lockheed Tristar. The Airbus was a European political response to this US market hegemony. Atypically, over the next 20 years this political market interference proved prescient as, with easy access to cheap government loans (all of which have since been fully repaid with interest), the bold Airbus designs and technical innovations soon challenged that of Boeing and particularly in the narrow-body market. The core of this challenge lay in the operating cost-efficiency of Airbus designs which was realised, in the main, through just two elements.

Foremost was the wing design and later the engines. An aerofoil (wing) at a positive angle of attack (α) to an airflow, creates a pressure differential between the upper and lower surfaces and hence, a lift force (L). The greater the airflow (ie. aircraft speed) the greater the lift. When equal to an object weight (W), it flies. With Lift being at 90° to the aerofoil axis, the positive α generates a reverse force, Induced Drag (ID – in orange in the diagram). The larger the α, the higher the ID. Airbus benefited from billions of design dollars of British wing profiling (based on those of gliding sea-birds) minimising that ID. The less the ID, the less the fuel burn. A measure of the success of this design was demonstrated by an A330 wide-body which, on loosing both engines at 40,000’ over the Atlantic, glided some 600 miles to land safely in the Canaries.

This advantage was further accentuated by a new generation of highly fuel efficient, by-pass engines.  The 737 had neither and, due to the very low ground-clearance of the wing, they faced severe engineering challenges to accommodate the significantly larger by-pass engine designs. As a result the new generation Boeings (737-800/900) were no match for the competing Airbus types (A320NG and A321)

As can be seen from the table above, the bypass engines on the A320/321-neos increased the former incremental advantage of the Airbus over its Boeing equivalent (B737-8/9) into a substantial one.  Until that point, Airbus had largely been playing catch-up: around 2015, the roles were reversed (see below).

This called for a completely new Boeing design and such was proposed by engineering (staffed mostly by former Boeing folk) shortly after the turn of the century. However, the multi-billion dollar proposal was deferred by corporate (now staffed mostly by former MD folk) which opted instead for the multi-100 million upgrading process. In large part this was due to the parallel need to prioritise a wide-body replacement for the B767 which was the B787 Dreamliner. This was the first Boeing aircraft to match the low drag profiled wings and computerised Fly-by-Wire (FBW) technology of their Airbus nemesis. While in production some 4 years ahead of its main Airbus rival (the A350) it was nonetheless years behind schedule and billions of dollars over budget (and ultimately outmatched by the later Airbus).  

So there was, and remains, no money available to deign, build and certify a new narrow body type, so Boeing were forced to opt for yet another upgrade of the 50 year-old 737 base-line design. In the short-term this proved a commercially astute decision with Boeing holding its own in the numbers game and being a lot more profitable overall than its rival. But the technical gulf between the Boeing and Airbus types was growing until, some 10 years ago, the bypass engines of the A320-Neo and 321-XLR series made it almost overwhelming.  So a way had to be found to fit the modern, and very much larger, by-pass engine to this old design. The problem was that the older engine types already only had a 19” ground clearance. So, as shown below, rather than locating the new engine under the wing as in the original classic designs, the bypass engine had to be moved forward of the wing so that it could be lifted higher off the ground.

Max-series

But moving the power plant forward impacted the Centre of Buoyancy such that, at high power settings, it would push the nose of the aircraft up with risk of stalling. That would require use of elevator to push it back down again which among other things, creates additional drag thus decreasing fuel efficiency (thus obviating the whole point of the exercise!).  The answer was to put a small tab on the elevator and to automate the process so as to catch and correct the nose-up movement at an insipient stage – that was the main function of MCAS (Manoeuvring Characteristic Augmentation System). The idea was to also make the aircraft fly and respond like the older 737-800s which had been sold in very large numbers: this the MCAS also successfully did.

So the Max also sold like hot cakes with some 5000 orders before the first unit entered service in Indonesia with a subsidiary of Lion Air (which was also the launch customer for the former B.900-ER and also one of the largest operators of that series). With that operator also diversifying into Airbus A320 options, this was a major coup for Boeing.  But, in the Sales department efforts to make the Max appear as an upgrade to which -800 series so that pilots could more readily convert, rather than new aircraft type requiring full certification and more onerous training, lay the seeds to the subsequent Max accidents. In Part-III, the germination of these fatal seeds will be followed in detailed slow motion.

Part-III: Sales wags Engineering.

In the first two parts of this article we saw how Boeing management supressed technical innovation and excellence to become a Wall Street darling. This allowed their rival Airbus to assume the lead both technically and commercially. While just holding their own in the wide-body market, in the larger narrow body sector, Boeing were getting trounced. Having neither the time nor the money to bring a new game-changer design into play, they opted instead to seek to match the competition by re-engining the venerable 737 design. This they did using a clever technical trickery – MCAS – to overcome the negative impact of the laws of aerodynamics. But to minimize the requirements relating to certification and subsequent conversion to type for the client airlines, the Sales department was allowed to obfuscate and minimise the engineering issues. The result was bumper sales – a commercial triumph.  

      Head to head

Then the nightmare started. Within a few months of entry into service, a Lion Air Max crashed into the sea shortly after take-off from Jakarta on a mild day with light breezes. With the Captain being a foreign national and the co-pilot relatively inexperienced, it suited manufacturer and operator alike to blame it on Pilot error. While the accident investigation followed it’s protracted course, that was the generally accepted view in the aviation industry. But then, five months later, a very similar accident occurred in Ethiopian Airlines also just after take-off and also in fair weather. Now, while Lion Air is an LCC in a poorly regulated developing nation, the national airline of Ethiopia is highly respected and run to very high standards by a bunch of experienced expats from the developed world. So the event was not so easily fobbed-off. As a result, led by the Chinese, more and more developed nations grounded the Max. The last to do so was the USA and then only after the Pilot’s Union wrote an open letter to the President resulting in it being grounded not by the FAA but by a Presidential Decree !

The root cause in each case was eventually found to be a failure in the angle of attack ‘α’ indicator. This is a simple mechanical pendulum device allowing the easy measurement of aircraft flight angle relative to the vertical, hence ‘α’. In the Ethiopian accident the sensor was found to have been broken by a bird strike; in Indonesia, after having dived into the sea at very high speed, no definitive prognosis could be made, but it was considered a reasonable assumption. Bird strikes are common hazard in aviation, so the two events could be considered appalling bad luck. But, as the investigations proceeded and multiple other casual factors came to light, it started to become abundantly clear that appalling management was equally to blame – and herein lies the scandal. This has been exposed in an excellent Netflix documentary – Downfall – by Rory Kennedy (yes, of ‘that’ family) issued late last year and on which much of this thesis is based. The failures cover almost every aspect of management within Boeing!  Let’s start with the technical.

In fully automated systems, everything must be duplex: if safety critical, then it’s triplex. The ‘α’ indication, being the fundamental driver of MCAS, is surely in the latter category. Yet it was simplex.! There are actually two such a sensors (to left / right of the nose) but no software provision was made to cover one or both failing except for a computing anomaly indication – thus effectively making this critical element simplex. At the time of writing, one can offer no logic for such a fundamental error: maybe it was a just factor of the sensor simplicity, that is was considered that there was nothing there to fail…..? That said, with man-in-loop (an earlier essay on Flight Automation refers), it would not in itself have been a big deal as the MCAS element could just be switched off and the aircraft flown manually.

It is here that the root cause of sales wagging the technical dog came into play. There were two main issues. Management wanted a speedy certification process to get the aircraft into service as quickly as possible so as to better compete with the A320-Neo family, and the Sales strategy was to minimise the conversion to type for B737-800/900 pilots, again emulating said 320-family, to be little more than a in-house computerised aircraft differences training with a standard line check by an authorised airline Training Captain on completion. This was instead of having to fly to the USA for a couple of weeks conversion Training with the OEM and the need to build specific simulators to accommodate the emergency aspects of that training.  If conversion to the new type could be accommodated with existing infrastructure, then time-lines and costs bringing the new type into service would be dramatically reduced for both the OEM and end-user Operators.  

So the OEM management decision was to ‘hide’ the MCAS within the auto-pilot as an auto-stabilization element (which, in effect, it was). This technical subterfuge was so complete that the only mention of MCAS in all of the technical and operational documentation was by over-sight, where it was left in the Glossary of Terms at the beginning.  Such is indicative that decisions with regard to this technical strategy was taken at the highest levels within the company. In fairness, there is a logic in this regard, in that the automated elements were really very simple and, as long as there was no failure, the system inputs would be so deep in the background of the aircraft’s operating system, as to be unnoticeable. So it was presented as a software ‘tweek’ to make this Max ‘feel’ like its 737-800/900 predecessors, which indeed, was essentially the case.  The problem was, it was not documented in any detail anywhere – not in the Pilots’ Ops. Manual, not in Technical Manuals, nor even in cockpit checklists. The Wall Street Journal advises that early in the subsequent investigation, a Boeing statement was that apparently it was policy “not to overload Pilots with too much information”!  No mention was even made of the two switches labelled ‘auto-stab.’ that turned off the MCAS.

Rory Kennedy’s Downfall documentary includes footage in a simulator showing what happens when the a indication fails. The pendulum effect of the broken a sensor input a high nose-up angle into the FMS computer: such was indicative of a stall. This causes various panel lights to start flashing, the (joy) stick shaker activates, a voice screams “stall, stall !” and the computer brutally shoves the nose down. The flying pilot could see there was nothing wrong so pulled the nose back up manually and the cycle restarts again getting more brutal each time as aircraft speed increases. The non-flying pilot frantically searches through checklists for information – there is none……. leaving the crew trying to understand what heck was going on as they loose control of the aircraft in a cacophony of cockpit noise, no doubt exacerbating things resulting in other mistakes. Such is the stuff of nightmares but, as a reality, there was no waking-up in a cold sweat, just a mercifully short screaming panic and oblivion. Actually all that needed to be done was to close the aforementioned couple of normal looking switches labelled ‘auto-stab’ and the MCAS would have been disconnected and the aircraft flown normally. But not only were these switches not documented, they were also tucked away at the back of the center console and so not readily visible. But this was stated nowhere in the cockpit checklists. In the USA the information had passed by word of mouth between crews, and was likely seen as a teething problem with auto-stabilization in a new aircraft type that would soon be sorted out, with the check-lists amended accordingly at the next update and as such, no big deal. Crews far away overseas were less well advised. Actually, the pilot that few the Lion aircraft the day before the crash, also had an MCAS problem, but with friends in the US, he knew what to do. On arrival in Jakarta, it is understood he entered it in the Technical Logbook. The engineers no doubt ground tested the system which, with the aircraft being horizontal on the ground, of course worked normally. That being the case, they would have entered “tested and assessed serviceable” in that aircraft’s  Technical Logbook (as is the normal procedure). The unfortunate Indian Captain assigned to the aircraft the next day had the same problem but was not so lucky and nor were his 180-odd passengers and crew !  

Conclusion

In the 18 months enforced down time since the accidents, the B737-Max has been virtually completely recertified by the FAA and the MCAS issue in particular is now fully resolved and properly documented, with pilots being properly trained in its use. The pendulum a sensor has now been made duplex. So one may be confident there will be no repeat in global Max operations of this sorry tale.

The same cannot be said for the Boeing company. Their quality management issues in manufacture are still on-going and, after the 10s of billions of lost revenue, fines, law suites and capital expenditure, one cannot imagine where they will find funds to develop a new mid-range aircraft design which they so desperately need to compete with Airbus. So, it is not impossible to image a scenario whereby Boeing chooses to withdraw altogether from commercial aviation and focus on their (larger) military market.

But, notwithstanding one’s harsh review of this recent scandalous history, the author of this piece, where possible, will always choose a Boeing over an Airbus. Why? Because, as stated in the former flight control essay, with the exception of the B-787, Boeing aircraft are flown by Pilots, while the more advanced (Fly-by-Wire) Airbus types are flown by a computer. Before one is sued for the publication of such an opinion, let it be said this is a subjective choice is based on no (accepted) objective evidence and hence, is solely a function of this Auther’s personal lack of digital empathy !

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