Aircraft Accidents and COVID Contingency

Four decades ago, I was a courier for Federal Express around Great Neck, NY. The techniques they taught us helped us plan out our day and route to conserve time, which allowed me to decrease the trips I made between Kings Point and Manhasset. It also assured the freight in my truck made the flight to Memphis. Later, I used these techniques all through my aviation career for Contingency planning.

During the COVID-19 Pandemic, the aviation industry has been riddled with doom forecasters carrying on about how life as we know it was over with. The media took to playing the blame game despite there being plans to get us through. The medical industry, however, continued to improve society’s chances of surviving life after COVID-19 because of contingency planning. So, let the media persist in drowning us in calamity after unendurable calamity as they stew in possible future disasters, e.g. birds and cats living together; Colin Kaepernick winning a seat in the US Senate or even, God forbid, another Star Wars sequel. Oh, the Humanity! We, in aviation, think beyond the adversity; there are those who foresaw the problem coming and planned around, through and past it.

On September 11, 2001, the Federal Aviation Administration (FAA) grounded all civilian traffic until September 13th, immediately during and following the 9/11 terror attacks, using similar techniques employed in the early 1960s defense test known as Operation Sky Shield. Though the processes used this year were not as aggressive – most airlines are still flying – the airline industry and the FAA have planned well before the 9/11 attacks for many contingencies, including pandemics, war and crippling worker strikes. It would be interesting to learn that these plans include various other debilitating situations and at different levels of intensity. Everyone prays these contingencies are never used, but it is always wise to plan for the worst – hope for the best. The trick is to affect the least number of employees as possible, keeping as many employed during the crisis.

How, then, would the airlines plan a contingency for surviving a one month-PLUS business interruption? The answer would be threefold: business-as-usual, adaption and what was spoken about in the first paragraph, namely the conservation of time.

To be sure, airlines, e.g. UPS, FedEx and other cargo carriers, have not been hit as hard as the passenger airlines; they have continued flying business-as-usual. Medicines, personal protection equipment, ventilators, etc. have been flown in and out of the United States (US), as well as across the domestic US, on uninterrupted schedules since before the lockdowns began. Indeed, the freight and the flights to many destinations have increased, improving the flow of medical goods, as well as the movement of civilian goods, e.g. foodstuffs, the equipment/materials needed to build said medical equipment, documents (mail), and any cargo that would keep the American economy going uninterrupted. While trucking is the preferred mode of transport, weather and distance make flying more logical.

Passenger airlines have moved some cargo. Restricted to the bellies, these cargo movements are limited where the passenger traffic normally supplements the flight costs. What is a passenger airline to do, especially with widebody aircraft normally moving hundreds of customers per flight? The airline adapts. Narrow body aircraft can be employed to move medical personnel from small towns unaffected to coronavirus hot zones, like New York City. Most narrow body aircraft can be filled with military personnel responding to government needs, airliners that are normally used in the Civilian Reserve Air Fleet, aka CRAF. These CRAF airliners are made use of regularly during peace and war time to move military personnel to support military lift dedicated to other pressing causes, like moving tanks.

Passenger airliners can also be converted to carry just cargo, even in the passenger cabins. Airlines, such as American and Delta Airlines, have dedicated widebody airliners to all-cargo flights; they are flown to many international destinations or Alaska, Hawaii and other US territories abroad. This happens in one of two ways. The first way, the seats are used to restrain boxes with added netting restraints covering the seat/box coupling, which is then restrained to the seat tracks in the floor under the airliner’s carpeting. This should require a minimal revision to the airline’s weight and balance (W&B) procedures.

The second way would be for the airliners to be stripped of the seats, carpeting and all non-essential equipment, e.g. meal carts, coffee makers, aft bathroom fluids, to reduce excess weight that would add to fuel costs. Mechanics could strip and then reweigh the airliner for a new empty weight center of gravity. At the same time, the FAA and the airline would revise the W&B procedures and train personnel and pilots to the new procedures, e.g. strapping the freight to the floors, determining weight zoning and how to build freight in those zones. Passenger flights will be reintroduced after the interruption; as the flight schedule is slowly increased, the all-cargo converted aircraft will be gradually returned to passenger service.

Pilots can conduct training during this time, utilizing large, well-ventilated classrooms or empty hotel meeting rooms, to assure social distancing. These days of Powerpoint teaching presentations make mobile classrooms more accessible, even utilizing remote classrooms. Simulators, where available, can provide pilots with continuous practice and training in the weeks that flying has been throttled back. Pilots who live far from the training facility can be moved by taking advantage of industry co-op agreement privileges, jumpseating in the cockpit to minimize social interaction with the passengers.

Certainly, not all air carriers can continue business-as-usual or adapt by converting its fleet to all-cargo airliners. What, then, can a certificate holder, such as an air carrier or repair station, do to remain actively employed? The best one could do would be to commit to a conservation of time, namely one that allows social distancing and the Great Outdoors, or, to be more specific, the Great Outside.

On daily flights, commercial airliners pick up maintenance discrepancies like children pick up colds; they can be numerous and at times hard to detect. In the digital age, while many discrepancies are reported via the aircraft’s computer, the electrical anomalies can be hard to trace down due to corrosion and the hundreds of wires going into one cannon plug.

In a similar way, structural problems can emerge for simple reasons of everyday use, e.g. salt air, humidity, residual deicing fluid, heat expansion or corrosive chemicals. With aluminum, the various types of corrosion are more evident; testing can bring out the faults, even those hidden beneath the surface of the metal. With composites, defects are less obvious; bonding of the layers and epoxies are subsurface and look, to the naked eye, normal, all the while allowing water to occupy the gaps and through expansion at high altitudes, destroy the composite component’s integrity.

These aircraft problems are not limited to electrical or structural; often regular components that require extensive ground time will fail and have to be deferred to a later date. Each aircraft is designed with the ability to suspend repairs on certain systems and components to allow for flight scheduling, parts ordering, repair planning and troubleshooting. These items do not reduce safety, but give the air operator time to respond.

These discrepancies do accumulate. Sometimes an operator needs time to address them or time to move the part to the aircraft. During this pandemic, the air operators are given the gift of time – some would argue too much time – but time, nonetheless. Planes that sit due to shutdowns can be troubleshot and repaired; wire harnesses can be wrung out and replaced. The abundance of ground time gives repair stations the chance to catch up, move overhauled components out to the air operators and clear their shelf stock, while bringing more in. Work can be accomplished outdoors to allow for social distancing. Aircraft areas can be zoned during phase checks to prevent close and/or tight working quarters.

Structural repairs that require long ground times now have enough time to make the repair while making the flight times not yet decided in the future. Patch repairs can be easily addressed; the patch can be removed, inspected, repaired and the patch reinstalled without affecting the flight schedule. Corrosion can be removed, redressed and any components reinstalled in a timely manner.

This COVID-19 situation can be viewed as a ‘glass-half-empty’ crisis. It has put a strain on all industries – some more than others – not just aviation. However, there are means to keep as many technicians and support staff working as possible; to keep pilots and flight attendants current, those whose airlines are flying and those who are not. It is a time for aviation, just like America, to show its very best.

Aircraft Accidents and Lessons Unlearned XXXVI: Midwest Express Flight 105

A Midwest Express DC-9-14

On September 6, 1985, Midwest Express flight 105, a twin-engine Douglas DC-9-14, registration number N100ME, crashed while taking off out of General Billy Mitchell Field in Milwaukee, Wisconsin (accident number DCA85AA036). As per National Transportation Safety Board (NTSB) report AAR-87/01, the flight was the victim of an accelerated stall after reaching 450 feet of altitude. The aircraft suffered what the report called, an uncontained failure (UF) of the number (#) 2 (right) engine, before rolling almost ninety degrees. The loss of lift led to impact.

The Probable Cause, per the report, “was the flight crew’s improper use of flight controls in response to the catastrophic failure of the right engine during a critical phase of flight, which led to an accelerated stall and loss of control of the airplane. Contributing to the loss of control was a lack of crew coordination in response to the emergency.” What were missing in the report were supporting facts.

After I posted Lessons Unlearned XXXIV: Avianca Flight 52, a former NTSB colleague of mine said that, “I was unfair to the Board; that I was hard on the NTSB investigators.” I never intended to be ‘unfair’ or ‘hard’ on any of the investigative agency reports I have reviewed, foreign or domestic. Instead, my focus has been – and will always be – on aviation safety and the improvement of safety by drawing attention to glaring mistakes that were missed; glaring mistakes that may have contributed to later accidents.

1st mistake: Per AAR-87/01, (no NTSB Archive information available) the #2 engine’s UF occurred at the 9th and 10th stage high pressure compressor; the high-pressure compressor spacer failed at takeoff power. The investigator reported that the sleeve had been reworked because its air seal was damaged. Regrettably, the investigator did not verify the process followed to repair the air seal was accomplished per the manufacturer’s instructions or whether the manufacturer would even approve the air seal repair.

2nd mistake: The NTSB concluded that the accident did not result from engine failure, but from the pilots’ actions, i.e. Pilot Error. The NTSB concluded that limited crew communications led to the accident. They implied the pilots intentionally flew into an accelerated stall. Both probable guesses were unlikely.

Both pilots were proficient in the DC-9; their training was current; a majority of their experience was in the DC-9. The cockpit voice recorder (CVR) transcript did not suggest otherwise. The flight began routinely; conversation was professional and friendly. ADDED NOTE: the flight attendant (FA) deserved credit for admirable calm under stress. As the plane stalled, the FA gave controlled orders to the passengers to assume a crash position. The FA was a professional to the end.

The DC-9 aircraft was designed to be flown on one engine, even continued, safe flight in the event of a single engine failure on takeoff. There was an experienced crew, clear weather and a well-designed aircraft with hundreds of thousands of hours of proven reliability in operation. How and why would the pilots intentionally place the airliner in an unrecoverable stall? From the reported facts, they didn’t. Several inconsistencies in the report demonstrated inexperienced investigator problems.

3rd mistake: The CVR and the FDR both showed a data ‘gap’ that occurred simultaneously with a loud ‘clunk’ (identified as the #2 engine’s UF). The NTSB report said the incredible coincidence was from “a jump in the foil [recording tape] position of the recorder”. However, per the CVR transcript, at takeoff, the #2 engine generator powered the recorders. When the #2 engine failed, the #1 engine took over the electrical load – as designed – resulting in a momentary gap. There was no ‘jump in the foil’ tape.

4th mistake: The #1 engine’s power reduction was ignored; this was an inexcusable oversight. Normally the #1 engine throttle would have been advanced – not retarded – to fly out of the emergency. Per the CVR, the pilots never said they advanced the #1 the throttle or not. Was the #1 engine fuel line cut by sharp metal flung out by the #2 engine UF? Investigators never looked at this. Instead, in the absence of FDR engine data, the NTSB made ambiguous CVR interpretations to draw conclusions. In addition, the CVR transcript never suggested the crew lacked coordination or that they deliberately flew the aircraft into a stall. The accident report’s Probable Cause was based on inexperienced speculation, not facts.

5th mistake: What proof was there that any liberated metal penetrated the fuselage? On page 12 of AAR-87/01, section 1.11.5, “the FDR indicated an excessive increase in the climb-rate …”. The NTSB explained this away as an FDR and side-slip induced errors. However, any breach in the fuselage’s pressure vessel would have equalized the cabin pressure to outside pressure, resulting in … an increase in climb-rate. An investigator with a maintenance background would have known this.

6th mistake: The emergency event lasted 15.5 seconds, during which the NTSB incorrectly speculated about a ‘lack of crew coordination’. At 4.5 seconds after the loud ‘clunk’, the Captain (the pilot flying) asked, “What do we got here, Bill?” before saying 3.1 seconds later, “Here …”. Bill, the first officer (FO), transmitted to air traffic control (ATC) that there was an emergency (at 7.6 seconds). This was confusion, not disorganization. Clearly the pilots were puzzled by multiple conflicting instrument readings. Why would both engines lose power? In the remaining seven seconds, did they see hydraulic pressure drop? Did fuel pressure go to zero? Maybe split elevators? Did the aircraft slowly begin rolling? They did not even have enough time to reach for the emergency procedures. Most likely the pilots suffered from astonishment in an untrained for event. They did not suffer from cockpit mismanagement.

7th mistake: What would hydraulic pressure loss or flight control jamming have to do with the #2 engine UF? The Midwest Express 105 accident occurred less than four years before United flight 232 and eleven years before Delta flight 1288; both of these accidents resulted from uncontained engine failures. They demonstrated the catastrophic damage that engine parts, e.g. compressor blades or internal components, could do to the fuselage and systems in line with the separated component’s trajectory. From AAR-87/01, investigation into the #2 engine’s cowls, mounts, the vertical or horizontal stabilizers, was rudimentary; the factual information documented in the report about such damage was limited.

The engines each provide hydraulic pressure from a hydraulic pump mounted on each engine’s accessory gear box. It was more likely that numerous compressor blades were suddenly slung outwards during takeoff power, not in one direction but in many directions, ricocheting off structure; they would have sliced through the engine case, tore fuel lines, cut into hydraulic lines or the pump. Hydraulic fluid would have vented to atmosphere and drove pressure to zero. Total hydraulic pressure loss would have made the flight controls less manageable, with the aircraft ‘low and slow’. This possibility was never looked at.

Another possibility would be liberated compressor blades or components that damaged systems inside the aircraft’s tail or stabilizers, as was later seen with United 232 and Delta 1288. Elevator or rudder control cables would have been bent, cut; the bellcranks or pulleys damaged; flight control hinges jammed by expelled engine pieces; liberated compressor blades shot upwards that struck the elevator as the horizontal stabilizer moved into the blade’s trajectory. These possibilities were never looked at.

These potential events would explain why the cockpit was unusually quiet during the event. The captain and FO were mentally searching their training; the cautious call to ATC, “… uh, we’ve got an emergency here”; the stick shaker added chaos to the crisis. The atmosphere within the cockpit was one of growing confusion followed by what was more likely an uncommanded roll and stall. The pilots were dealing with conflicting information and ambiguous gauge readings within an inadequate allotment of time at a low altitude. It was a cruel hard fact: the aircraft could not be saved, no matter what they did.

It is an archaic process that NTSB Board Members, with no transportation experience, should still wield the power to cripple safety with ignorance. On one hand, the wrong party was blamed; on the other, the true root causes were ignored. Once published, an accident report is permanent; there are no appeals, no do-overs; no one to suggest that the investigation was done incorrectly. In the case of Midwest Express 105, the pilots have, for eternity, been saddled with the brand of Pilot Error for the crime of being in an aircraft that could no longer fly.

On February 3, 1987, the NTSB issued accident report AAR-87/01. The report was ambiguous; it was pure speculation; the report solely blamed two qualified pilots for an accident that was more a mechanical series of tragic events than operational mistakes. Root cause analysis would have properly interpreted the evidence. Safety was not improved. And isn’t improving safety what these accident reports are all about?