Boeing to Begin 737 MAX Recert Flights

[sora.sky]

After more than a year of being grounded, Boeing is to start a series of FAA recertification flights for the 737 MAX type. 

The first flight occurred today (6/29/2020) but is just the first step in a long haul to bring a very popular aircraft type back into service. 

 

Quote

If the flights are successful, it could still be months before the planes are deemed ready to fly again. If the F.A.A. identifies further problems, Boeing may need to make additional changes. The crashes were caused in part by anti-stall software on the Max, known as MCAS, which automatically pushed the nose of the planes downward. Boeing developed a fix for the software, though regulators have identified other problems since.

My thoughts

Boeing has had a really rough past few years, events of their own design. Same goes for the FAA.

-> The 737 lineup has had its reputation tarnished, with less informed travelers even protesting about getting on proven 737NGs that large operators worldwide fly with little incidence.

-> Airlines have cancelled their orders for the MAX; even Boeing loyalists like Southwest Airlines in the US have purportedly had serious talks with Airbus to take on competitor aircraft: the A320NEO and A220.

-> Civil aviation authorities will no longer see the FAA's certifications of aircraft as the gold standard. More countries will independently certify; those that are unable to do so will likely look to the EU or the Chinese's civil aviation authorities for guidance as opposed to the FAA. Many on aviation focused forums have expressed they will wait until the Chinese have signed off.

 

 

Sources

https://www.cnbc.com/2020/06/29/faa-boeing-737-max-test-flights-a-milestone-in-recertification-after-crashes.html

https://www.nytimes.com/2020/06/28/business/boeing-737-max-faa.html

[givingtnt]

Too bad, Boeing is the dumbest company to ever put a plane in the sky.

I might be biased towards the A220 (not that the max can even come close, that's why they asked for that 300% tax lol) 
but Boeing needs to eat dirt for a while.

[greenhorn]

I think there will be some people who will be very reluctant to fly on a MAX, regardless of how well it has been tested. A bad reputation can effectively kill an aircraft type, this happened to the DC10 (even though the refined versions were probably quite safe, but the many accidents suffered by the earlier models scared too many people).

[Soppro]

Good to see it back in the sky again. FAA will also need to rescue its reputation. It's going to be a dangerous period in the long term for the 737, the MAX series and insurgence of COMAC's C919 (basically a 737 rip off with aluminium body which they'll sell at half the price) could very well lead to its demise. I hope Boeing will deal with those challenges accordingly.

[darrenvox]

Sooo true...I'm just hoping all sort of other planes will fly too..some airports are looking like museums right now

[compconosuire]

what even happened with it? I know it crashed but I dont know any specifics of what actually caused it

[GDRRiley]

36 minutes ago, compconosuire said:

what even happened with it? I know it crashed but I dont know any specifics of what actually caused it

bad software mixed with an unstable aircraft

[Real_PhillBert]

This is what happens when engineers get overruled by accountants. Sadly, this happens FAR more often than people think. 

[BuckGup]

25 minutes ago, Real_PhillBert said:

This is what happens when engineers get overruled by accountants. Sadly, this happens FAR more often than people think. 

That's what happened with the challenger. There was 7 engineers who specifically said DO NOT launch or it has an extremely high chance of blowing up on the launch pad. But they really wanted to get the launch to lineup with the presidents speech so they did it anyways

[HM-2]

1 hour ago, Real_PhillBert said:

This is what happens when engineers get overruled by accountants. Sadly, this happens FAR more often than people think. 

That's not quite what happened in this case; more a disconnect between the culture within software development teams and aviation more generally. Bean counting did have something to do with it, inasmuch as Boeing fudged the software fixes to bypass physical problems that manifested because they were intent on making sure that the aircraft didn't need to go through a full type approval process (and was instead treated as a variant rather than an existing model); the aim of this being to lower operating costs and therefore make it more appealing, particularly in the budget airlines who don't want to pay for the expensive simulator time for their pilots to get type approved on new aircraft.

 

Really good writeup here - https://spectrum.ieee.org/aerospace/aviation/how-the-boeing-737-max-disaster-looks-to-a-software-developer

[TetraSky]

INB4, Boeing rebrand the 737 MAX to something else entirely in an attempt to salvage the existing aircraft. If only just to fool the common passengers into boarding them.

[ryanregowhite]

On 6/30/2020 at 4:18 AM, GDRRiley said:

bad software mixed with an unstable aircraft

The aircraft was not unstable. I was just reacts differently in a stall. The system was put in place to keep the type rating. 

 

Also, bad maintenance and pilot error played a major role in both accidents. With Lion Air the aircraft was not airworthy the aircraft had a broken AOA vain from the previous flight. Maintenance did not fix it correctly. And the pilots failed to react correctly. Now how can this be? Boeing did not include this in the difference course and that is true. But the procedure to disable MCAST is a memory item that has been on Boeing aircraft since the 60s. A memory item is a checklist that pilots must know off the top of there heads. a trim runaway is when an aircraft trim is moving un commanded this could be for a variety of reasons. The 707 727 737 trim runaway procedure is 

 

1. control column ............................Hold firmly

2. Autopilot (if engaged)..................Disengage 

                      Do not reengage the autopilot 

                      control airplane pitch attitude manually with

                      control column and electric trim as needed.

       3. Atuottrottle (if engaged)................Disengage

       4. If the runway stops after the autopilot is disengaged: 

-------------------------------------------------------------------------------------

      5. if the runaway continues after the autopilot is disengaged 

                    STAB TRIM CUTOUT

                    Switches (both)......................Cutout

                     if the runway Continues 

                              Stalbiser 

                              trim wheel ....................Grasp and hold 

-------------------------------------------------------------------------------------------

        6. Stableliser.......................................Trim manually

        7. Anticipate trim requirements

 

This is in the basic 737 training for all models the crew failed to correctly follow this procedure (although it is possible that thy did not receives this training correctly because lion air has an atrocious history for crew training) The European crew also failed to correctly follow the procedure. 

All of this said, Boeing is not innocent and deserves a lot of the blame. But it is important not to lose sight that an accident is never a single cause. Its a chain of events.

 

All of this said, Boeing is not innocent and deserves a lot of the blame. But it is important not to lose sight that an accident is never a single cause. Its a chain of events. 

 

 

[jones177]

I think they all should be converted to freighters. There is no point using them for anything else now. 

 

Way back in the 70s I was sitting on a tug at MIA waiting for a DC8 to land so I could hook up and tow it over to the hanger. While I was waiting I noticed a 727 coming it hot and high. As it "touched" down one of the main landing gear brock and it went down the runway dragging a wing. I thought it would be a wright off since not only did it drag a wing for half the runway but there was so much torque on the fuselage that the rear doors pooped open.

The next day Boeing came and insected the plane and the lead mechanic for the plane told me that Boeing was going to rebuild it.

I could not believe it.

A few days later a 707 with Boeing markings on it was parked beside the 727 and the Boeing technicians worked day and night and got the 727 back in the air in less than a week. 

To me they were the epitome of American know how and ingenuity. It is sad to see them as they are today.

 

On a side note as the rear doors of the 727 popped open what looked like a big light brown dog jumped out. Later as I was putting away my tools I learned that it was not a dog at all but a full grown male lion. They had put it in the tool cage for safekeeping and I only noticed it when I was inches away. 

 

    

[sora.sky]

6 hours ago, jones177 said:

I think they all should be converted to freighters. There is no point using them for anything else now.    

I doubt there's enough cargo demand to convert all parked 737 MAX's. Plus cargo airlines like buying tired twin aisle jets from the passenger airlines to convert, since they're going to be standing on the ramps most of the time.

 

The 737 MAX will carry passengers again. It will be one of the most scrutinized airframes when all is said and done. 

 

Its irrelevant now in the world of the coronavirus, but in a pandemic free world where a 737 MAX was never allowed to fly again, airlines would have had growth/renewal plans set back years. I believe right before the virus broke out, back of the line for A320neo production slots meant waiting until the end of the decade.

[jones177]

6 hours ago, sora.sky said:

I doubt there's enough cargo demand to convert all parked 737 MAX's. Plus cargo airlines like buying tired twin aisle jets from the passenger airlines to convert, since they're going to be standing on the ramps most of the time.

 

The 737 MAX will carry passengers again. It will be one of the most scrutinized airframes when all is said and done. 

 

Its irrelevant now in the world of the coronavirus, but in a pandemic free world where a 737 MAX was never allowed to fly again, airlines would have had growth/renewal plans set back years. I believe right before the virus broke out, back of the line for A320neo production slots meant waiting until the end of the decade.

Most airlines carry cargo in the belly of their aircraft and they are not flying. Air cargo rates have more than doubled. Any plane with a cargo door is a money maker right now.

The wide body jets are great for international cargo but are ill suited to regional flights and that is the market for a 737 cargo aircraft.

 

Back in my day it was the DC 10 that had a bad rep and they were converted to MD 10s and later MD 11 cargo aircraft.

I worked on them and there was nothing wrong with the aircraft but they had a bad reputation with the public that was mostly due to the negligence of ground staff(the cargo doors were not idiot proof).  

 

You may be right though. I remember the Airbus plowing through trees at an airshow(1988) and it did not seem to deter passengers from flying on them. 

 

[HM-2]

6 minutes ago, jones177 said:

they had a bad reputation with the public that was mostly due to the negligence of ground staff(the cargo doors were not idiot proof).

The DC-10 issues were a combination of penny-pinching and intentional design; having an outward opening cargo door means you get more cargo space but massively elevates the risk of explosive decompression if the locking mechanism fails. Per the Applegate memo, McDonnell Douglas were aware of design issues in the cargo door locks but chose not to implement either a more secure lock mechanism or venting within the cargo bay which would limit the likelihood of explosive decompression because both were too expensive and would require grounding aircraft already in service. The susceptibility of the DC-10 to catastrophic in-flight breakup caused by cargo door failure had been known since 1970.

 

The Airbus crash noted above was caused by pilot error rather than a design fault. 

[Monkey Dust]

8 hours ago, sora.sky said:

I doubt there's enough cargo demand to convert all parked 737 MAX's. Plus cargo airlines like buying tired twin aisle jets from the passenger airlines to convert, since they're going to be standing on the ramps most of the time.

 

The 737 MAX will carry passengers again. It will be one of the most scrutinized airframes when all is said and done. 

 

Its irrelevant now in the world of the coronavirus, but in a pandemic free world where a 737 MAX was never allowed to fly again, airlines would have had growth/renewal plans set back years. I believe right before the virus broke out, back of the line for A320neo production slots meant waiting until the end of the decade.

I wonder if the Coronavirus and impending recession will help the 737 MAX in the long run. Lots of planes are getting scraped early at the moment, once the time comes to rebuild, Boeing will have a load of ready built 737MAXs to sell. When the recovery happens a 'just needs painting in the carrier's livery' 737 MAX will trump waiting for an Airbus order to be filled when there is a rush to rebuild capacity.

[jones177]

9 minutes ago, HM-2 said:

The DC-10 issues were a combination of penny-pinching and intentional design; having an outward opening cargo door means you get more cargo space but massively elevates the risk of explosive decompression if the locking mechanism fails. Per the Applegate memo, McDonnell Douglas were aware of design issues in the cargo door locks but chose not to implement either a more secure lock mechanism or venting within the cargo bay which would limit the likelihood of explosive decompression because both were too expensive and would require grounding aircraft already in service. The susceptibility of the DC-10 to catastrophic in-flight breakup caused by cargo door failure had been known since 1970.

 

The Airbus crash noted above was caused by pilot error rather than a design fault. 

Cargo doors on most aircraft open out. The planes that I worked on all opened out except for the Lockheed Electra. That includes the 707, 727, 747, DC 10, L1011 and many more. So to me not a design flaw. 

The problem with the locks on the DC 10 was that they looked closed properly from certain angles when they were not.

 

Usually I would be already on the tug for the push back when these doors were closed so they were not inspected like the rest of the airplane by qualified personnel.  Also back then the ground man was on the tether communicating with the cockpit so they had a limited view as well.

 

The Airbus crash was a tragedy but the pilot should never have been tried. 

 

  

[HM-2]

3 hours ago, jones177 said:

Cargo doors on most aircraft open out. The planes that I worked on all opened out except for the Lockheed Electra. That includes the 707, 727, 747, DC 10, L1011 and many more. So to me not a design flaw. 

I didn't mean to suggest the simple fact of an outward opening cargo door was a design flaw so sorry if I was unclear there. It's a design decision that has clear financial benefits but introduces additional risks that require managing (as unlike a plug door it isn't self sealing); it was the cost cutting around these safety controls that resulted in the failures.

 

3 hours ago, jones177 said:

The problem with the locks on the DC 10 was that they looked closed properly from certain angles when they were not.

This incident actually formed a case study In some recent work we've been doing around critical control safety evaluation, and my understanding is that it's somewhat more complex than that. The lack of clear visual indicator that the doors had latched fully was one aspect, but the specific design of the latch mechanism was inherently flawed.

 

The door could be closed without excessive force and appear sealed to both ground crew and the pilots whilst not actually locking fully, and essentially having all in-flight forces including pressurisation handled by three small aluminium pins which were in no way designed to handle such stress. The entire mechanism was described as "fatally flawed" by the NTSB, and carriers were left to effectively institute their own fixes as despite the findings of this report no airworthiness directive was issued around door mechanisms or the lack of cargo hold ventilation.

 

 

 

Actually the while debacle is eerily similar to that of the 737 Max.

• In both instances an intentional design decision was made that was primarily financial in its reasoning.
• In both cases, systems were put in place the try and mitigate these decisions that were obviously substandard and lacked any "fail-safe" process.
• In both cases a serious incident- one severe, one calamitous- illustrated the folly of these decisions.
• In both cases, a second calamitous incident occurred because the actions taken to mitigate the risk of future incidents were underwhemling.

Both were avoidable with proper foresight, planning and risk assessment. The same is true of the Flight 232 incident involving the DC-10 which again illustrates a lack of failsafes (in this instance the decision not to incorporate any hydraulic fuses) along with a design decision that didn't properly assess possible risks (routing all three hydraulic systems through a 30cm conduit in the tail that lay within a likely debris path of an uncontained engine failure). But all credit to McDonnell Douglas, they at least fixed both of these issues after they'd caused fatalities and as you rightly point out the DC-10 lived a pretty long life.

 

 

 

You may remember as well but this isn't the first significant design flaw with the 737 range. There were at least two and possibly as many as six fatal crashes causer by rudder hardovers resulting from a design flaw in the rudder control unit. In these instances injecting hot hydraulic fluid into a cold unit (such as during descent manoeuvring after high altitude cruise) resulted in the rudder locking very often in completely the opposite direction to the pilots input.

 

I suspect we'll all eventually forget about the Max crashes, probably to our detriment from the perspective of avoiding repeating history, as we did with the 737 rudders and DC-10 doors.

 

3 hours ago, jones177 said:

The Airbus crash was a tragedy but the pilot should never have been tried. 

He was certainly negligent. He performed a manifestly dangerous maneuver in the course of what was effectively "showing off" a system he didn't fully understand the functionality of.

 

As for whether he should have been tried, the French standards for negligent manslaughter are very different to those here in the UK as is the sentencing. Getting ten months for killing 5 people seems fairly light to me, he probably would have been tried under health and safety laws here in the UK and got significantly more.

[jones177]

1 hour ago, HM-2 said:

I didn't mean to suggest the simple fact of an outward opening cargo door was a design flaw so sorry if I was unclear there. It's a design decision that has clear financial benefits but introduces additional risks that require managing (as unlike a plug door it isn't self sealing); it was the cost cutting around these safety controls that resulted in the failures.

 

This incident actually formed a case study In some recent work we've been doing around critical control safety evaluation, and my understanding is that it's somewhat more complex than that. The lack of clear visual indicator that the doors had latched fully was one aspect, but the specific design of the latch mechanism was inherently flawed.

 

The door could be closed without excessive force and appear sealed to both ground crew and the pilots whilst not actually locking fully, and essentially having all in-flight forces including pressurisation handled by three small aluminium pins which were in no way designed to handle such stress. The entire mechanism was described as "fatally flawed" by the NTSB, and carriers were left to effectively institute their own fixes as despite the findings of this report no airworthiness directive was issued around door mechanisms or the lack of cargo hold ventilation.

 

 

 

Actually the while debacle is eerily similar to that of the 737 Max.

• In both instances an intentional design decision was made that was primarily financial in its reasoning.
• In both cases, systems were put in place the try and mitigate these decisions that were obviously substandard and lacked any "fail-safe" process.
• In both cases a serious incident- one severe, one calamitous- illustrated the folly of these decisions.
• In both cases, a second calamitous incident occurred because the actions taken to mitigate the risk of future incidents were underwhemling.

Both were avoidable with proper foresight, planning and risk assessment. The same is true of the Flight 232 incident involving the DC-10 which again illustrates a lack of failsafes (in this instance the decision not to incorporate any hydraulic fuses) along with a design decision that didn't properly assess possible risks (routing all three hydraulic systems through a 30cm conduit in the tail that lay within a likely debris path of an uncontained engine failure). But all credit to McDonnell Douglas, they at least fixed both of these issues after they'd caused fatalities and as you rightly point out the DC-10 lived a pretty long life.

 

 

 

You may remember as well but this isn't the first significant design flaw with the 737 range. There were at least two and possibly as many as six fatal crashes causer by rudder hardovers resulting from a design flaw in the rudder control unit. In these instances injecting hot hydraulic fluid into a cold unit (such as during descent manoeuvring after high altitude cruise) resulted in the rudder locking very often in completely the opposite direction to the pilots input.

 

I suspect we'll all eventually forget about the Max crashes, probably to our detriment from the perspective of avoiding repeating history, as we did with the 737 rudders and DC-10 doors.

 

He was certainly negligent. He performed a manifestly dangerous maneuver in the course of what was effectively "showing off" a system he didn't fully understand the functionality of.

 

As for whether he should have been tried, the French standards for negligent manslaughter are very different to those here in the UK as is the sentencing. Getting ten months for killing 5 people seems fairly light to me, he probably would have been tried under health and safety laws here in the UK and got significantly more.

There was a few things like the DC 10 cargo doors that made me uncomfortable and in the end I did not mind leaving the industry.

 

As for the Airbus,  like most at that time I trusted the cable controls systems that I think is still in the 737 and I thought the implementation of fly by wire in the plane was too soon.  

I still drive stick shift so I am not the type to embrace new technology.

 

 

 

[spartaman64]

On 7/1/2020 at 2:19 PM, ryanregowhite said:

snip

i was going to say that but I did some research and apparently thats what the Ethiopian air pilots did but apparently the forces on the stabilizer is too great and they cant manually trim it

edit: the last one was the wrong video sorry