Lion Air

[JDNSW]

Listening to the news about the plane crash in Indonesia, sounds to me like a partly blocked static air system. I thought airliners had at least two static air sources so I can't understand how something this simple could result in the loss of the aircraft.

[Hugh Jars]

Listening to the news about the plane crash in Indonesia, sounds to me like a partly blocked static air system. I thought airliners had at least two static air sources so I can't understand how something this simple could result in the loss of the aircraft.

B737 has 3, including the standby. The big problem can be when a situation like this presents itself, identifying the side giving the incorrect information. Nonetheless, there is a memory checklist for ‘Airspeed Unreliable’.
The scenario has been trained in recurrent sim sessions since the year dot, but has been at the forefront since the Air France prang a few years back.
Any pilot worth his salt will know the attitude/thrust settings for various flight regimes, as this is the key to beginning the troubleshooting process.
https://uploads.tapatalk-cdn.com/20181101/bb139c0aac69cfaf114054ad42ff32b2.jpg

[AndyG]

And this is why i fly QANTAS

[Hugh Jars]

And this is why i fly QANTAS

Some airlines I refuse to fly in the region:
Lion Air
Malindo
Garuda
Air Asia

Caveat emptor.

[Fourgearsticks]

Wheren't the conditions clear VFR? I have no idea on heavys but don't you get some feedback on speed either control/noise/feel? I have worked in Indo for a while and used to dred flights. Last time I was on Loin air the aircraft from about 5 miles out on final was rolling 45 degrees side to side all the way down final till I thought they were going to ground the wingtip. I didn't fly Loinair after that but was forced to fly their lines like Batik. Every flight without exception the flight crew were smoking the entire flight, the pax cabin had consistant cigarette smoke. No pax or cabin crew were smoking so only alternative is pilots.
The mob I was flying for for tax reasons were operating on CAR 135, the aircraft were maintained very badly and parts were replaced by cheaper non factory tagged or even worse local manufactured parts. The maintenance chief stated the factory that produced the aircraft had safety standards were too high and the price charged for spares was too high.
Loinair will blame the aircraft manufacturer or the pilot, any blame will be deflected away from Lionair with the help of Indo authorities.

[Hugh Jars]

VMC it was. There is a very interesting bunch of videos on utube called ‘Children of Magenta’. Not saying that an airspeed unreliable was the cause. The DFDR will reveal all.

[Bearman]

When I was working for Qantas years ago we were the ground handling agent for Garuda. After seeing the things their tech and cabin crew would try to bring through security I would never fly an Indonesian airline. They would blatantly try to flaunt IATA restictions.

[weeds]

Some airlines I refuse to fly in the region:
Lion Air
Malindo
Garuda
Air Asia

Caveat emptor.

Is it still relevant advice that one should (where possible) only fly with airlines that are allowed to land/operate in Australia? The theory that CASA standards were higher than other countries.

Although work flew me Malindo Air this year out of Brisbane and I vowed never to fly with them again.

[Hugh Jars]

Malindo, Garuda and Air Asia still fly to Australia. CASA (the regulator) is a sloth in dealing with this.
I will not fly on them, even though they come here.
Just being in the same airspace and listening to their radio work is alarming enough.

[JDNSW]

Thanks for the detailed information - I was hoping someone would come up with something like that. (My experience is limited to a wasp nest in the pitot tube of my Auster!)

One perhaps relevant comment I have seen in relation to this accident is that the problem is probably not either a specific defect in the aircraft, or a specific lack of training, but the cultural attitude to safety and risk.

(And lest we get above ourselves, have a read of some of the Australian airline operations not too many years ago!)

[Hugh Jars]

Indeed, JD.
The mud wasp is a significant threat in Brisbane at the moment. Our engineers install the pitot covers as soon as we park - even on a 30 minute turn. They are quick little buggers (the wasps).
From memory, we have had 2 instances of unreliable airspeed as a result of mud wasp activity prior to this procedure.

Your remark about safety culture hit the nail on the head [emoji846]

[Fourgearsticks]

I used to travel with Garuda to Indo. I found cabin crew were helpful, aircraft were clean and generally had better service than Qantas.
With Qantas most flight I went on had stressed cranky cabin staff, aircraft were dirty with seat backs filled with rubbish.
I worked from West Papua to Sumarta and a few spots inbetween, I had no choice than travel with Lion or one of their companies.

[JDNSW]

Indeed, JD.
The mud wasp is a significant threat in Brisbane at the moment. Our engineers install the pitot covers as soon as we park - even on a 30 minute turn. They are quick little buggers (the wasps).
From memory, we have had 2 instances of unreliable airspeed as a result of mud wasp activity prior to this procedure.

Your remark about safety culture hit the nail on the head [emoji846]

You would not guess where I had the mudwasp incident - no, not Brisbane, Redcliffe!

My Auster had an automatic pitot cover (are you familiar with them?), which was lifted clear by the airflow once the plane was moving at any speed. Unfortunately, I had parked for a few hours facing into wind strong enough to lift the cover off!

[Hugh Jars]

You would not guess where I had the mudwasp incident - no, not Brisbane, Redcliffe!

My Auster had an automatic pitot cover (are you familiar with them?), which was lifted clear by the airflow once the plane was moving at any speed. Unfortunately, I had parked for a few hours facing into wind strong enough to lift the cover off!

Yes JD, they are a great idea when they work. A couple of Cessnas I used to fly had them. Trouble is those sneaky little buggers find the smallest gap, and they’re up there like a rat up a drainpipe...

[JDNSW]

Latest information from Indonesia says the 737's angle of attack indicators were giving conflicting readings as well as the airspeed and altitude readings being conflicting. How does the angle of attack indicator on these work?

[Hugh Jars]

Latest information from Indonesia says the 737's angle of attack indicators were giving conflicting readings as well as the airspeed and altitude readings being conflicting. How does the angle of attack indicator on these work?

Hi JD. If you look at the scematic I posted further up the thread, you’ll see an alpha vane on each side of the nose. The little wing-shaped blade flies through the relative airflow at flying speeds. It stays aligned with the flow as the aircraft changes pitch (AoA) during flight. Those changes are transmitted elecronically and used with air data in the ADIRU’s to give output to the flight instruments (and a bunch of other equipment on the aeroplane).

Photo attached of alpha vane (circled) RHS B737NG.https://uploads.tapatalk-cdn.com/20181108/0fd023a6f186be6dc7e6028295e23b90.jpg

[Hugh Jars]

JD, here is a test board on gate 43 in Brisbane, taken yesterday. There are samples of various pitot tubes, as used on the aircraft that might park at that gate.
The idea is to research why the mud wasps do what they do. Info from our engineers is that they prefer a particular tube, but will use any.https://uploads.tapatalk-cdn.com/20181108/bdd9254240b2275ac15096125048a442.jpg

[weeds]

JD, here is a test board on gate 43 in Brisbane, taken yesterday. There are samples of various pitot tubes, as used on the aircraft that might park at that gate.
The idea is to research why the mud wasps do what they do. Info from our engineers is that they prefer a particular tube, but will use any.https://uploads.tapatalk-cdn.com/20181108/bdd9254240b2275ac15096125048a442.jpg

You say it’s a test board.....do they remove them off the plane to be tested??

[Hugh Jars]

I have no idea mate. They’re probably old ones with failed heating elements, or some other defect.

[JDNSW]

How could they give incorrect/conflicting readings? Presumably in the electronic transmission - sounds a bit as if in this case the angle of attack indicator was replaced, but that did not fix the problem.

Surely the pitot/static system is direct reading, with no intermediate electronics? Perhaps in addition to providing input to other systems.

[cripesamighty]

Saw this today

FAA issues 737 MAX emergency AD - Australian Aviation (https://australianaviation.com.au/2018/11/faa-issues-737-max-emergency-ad/?inf_contact_key=e8eda77263dd0ece02c860739b27a8dc4 b40cf01cb446f3366ce34de530900a9)

[Milton477]

I have often wondered if the big guys can "feel" their aircraft if flying ok without the need for instruments in VFR conditions. Is aviation automation making modern pilots seat of their pants numb?

[JDNSW]

The emergency AD issued by the FAA seems to be saying that a faulty attitude sender can cause uncommanded trim changes. And it seems that replacing the sender did not fix the issue. Possibly a software issue?

[Graeme]

I understood that the gauge was replaced, not a sensor, but perhaps the same item.

[JDNSW]

It gets hard to interpret some of the news reports - it seems a lot of reporters don't know the difference between altitude and attitude (or can't spell!), for example.

[101RRS]

I have often wondered if the big guys can "feel" their aircraft if flying ok without the need for instruments in VFR conditions. Is aviation automation making modern pilots seat of their pants numb?

I agree - yes is a major worry that pitot issues may have cause instrumentation issues BUT in the flight conditions the first rule of airmanship should apply which is simply fly the aircraft. In my view an experienced heavy pilot should have the "feel" of the aircraft even with the cockpit control remoteness from the control surfaces. In clear conditions where the ground and horizon is visible a qualified heavy pilot should still be able to fly the aircraft even with all instruments covered by their "seat of the pants".

However, as seen in many Air Crash Investigation shows heavy pilots get distracted by conflicting instruments and trying to resolve the conflict rather than applying the first rule of airmanship. With my limited flying experience it seems that this ws the case here, instrument conflict, trying to resolve and then loosing control. Also I bet the autopilot was engaged with it taking input from the dodgy sensors compounding the issue for the pilots.

Yes it is easy to guess from my lounge room but thats what we do. In view of Boeings recent advice on the aircraft (a new model) maybe there is a design element that started the problem in the first place.

Just my thoughts.

Garry

[superquag]

Jabiru... or Antonov , the same equation applies: Power + Attitude = Performance. And in VFR conditions, the most accurate, reliable and easily read Situational / Attitude Indicator is found outside the cockpit, - you know, the environment you're travelling in...


I was hammered with the notion that the first priority is always to 'FLY the aeroplane, - distractions can wait'.
- Great advice for piloting a car.

That, and placing less reliance on 'automation' (Cruise Control on bendy roads) are the Take-Home lessons from this tragedy.

[Hugh Jars]

The alpha vane transducer/s was replaced. There is no AoA gauge in the B737. For all intents and purposes, the ADI is the primary instrument.
It is possible to fly on limited panel, but the notion of being able to fly on no instruments with no outside visual reference is a furphy. Humans are not designed to fly with the design of our vestibular systems without a visual reference, such as an horizon or ADI. Google ‘leans’ ‘spatial disorientation’ ‘somatogravic illusion’.
Those of you who fly as passengers in jets experience a form of somatogravic illusion every takeoff (or some aborted landings). I often hear ‘jeez, the plane was going up at 45 derees!’ In reality, probably 10-15 degrees body angle, the rest was somatogravic illusion caused by the acceleration of the aircraft. I know several pilots who have been killed by this....

With a total loss of flight instruments and no visual reference, your time is numbered.

That’s why the flight instruments are duplicated or triplicated and powered from different sources - The idea is to have *something* available in the event of a system failure. What’s worse (as appears to be the case here) is that it isn’t a simple failure, but seems to be serviceable instruments giving invalid indications. That would be a nightmare. But there are procedures for identifying the faulty system (assuming you have time and altitude).

From experience I can tell you it’s a damn side easier to fly on limited panel with the instruments failed or covered up than dealing with incorrect information, because as pilots, we’re taught to trust the instruments (to a certain point), and NOT the seat of the pants.

[bsperka]

Jabiru... or Antonov , the same equation applies: Power + Attitude = Performance.


I was hammered with the notion that the first priority is always to 'FLY the aeroplane, - distractions can wait.

Aviate, navigate, communicate is the mantra that I've heard

[JDNSW]

According to what I have read, the accident was in VMC and daylight (or dawn at least); there should have been a visible horizon, so Hugh's comment about flying without a visual reference is not applicable. But it is easy to see how things could rapidly come unstuck if instruments were apparently working, but giving incorrect readings, especially if the same incorrect information was being fed to an engaged autopilot.

[Fourgearsticks]

As I said I don't know much about heavies, aren't there at least 3 AH's or AI's or whatever they are called these days? They operate independently? I asked earlier, do heavies give any feedback control wise with extremes of speed?

[Hugh Jars]

737 has 2 primary ADI’s (Attitude Director Indicator) and one ISFD (standby). The ADI’s form part of the Primary Flight Displays (PFD).
https://uploads.tapatalk-cdn.com/20181109/b83f411b437e10dc8efbd76f0da8fdc9.jpg
MAX PFD

https://uploads.tapatalk-cdn.com/20181109/eb11d2e0217a360f4d032f9f2aec3064.jpg
IFSD

There is not really much feedback (except for louder noise if you’re going faster. Some of the flight controls have artificial feel, but are all powered.

The 737 has inputs to move the stab trim in various flight regimes independently of the flight crew. The MAX has additional system called MCAS, which is believed to have driven the stab to full nose down as a result of faulty data from the alpha vane.

There is a procedure for runaway stabiliser (which this would have looked like). Whether they did that procedure is unknown.

[Fourgearsticks]

Sounds like they were in strife then

[LRJim]

737 has 2 primary ADI’s (Attitude Director Indicator) and one ISFD (standby). The ADI’s form part of the Primary Flight Displays (PFD).
https://uploads.tapatalk-cdn.com/20181109/b83f411b437e10dc8efbd76f0da8fdc9.jpg
MAX PFD

https://uploads.tapatalk-cdn.com/20181109/eb11d2e0217a360f4d032f9f2aec3064.jpg
IFSD

There is not really much feedback (except for louder noise if you’re going faster. Some of the flight controls have artificial feel, but are all powered.

The 737 has inputs to move the stab trim in various flight regimes independently of the flight crew. The MAX has additional system called MCAS, which is believed to have driven the stab to full nose down as a result of faulty data from the alpha vane.

There is a procedure for runaway stabiliser (which this would have looked like). Whether they did that procedure is unknown.FSX?

[Hugh Jars]

FSX?

What is FSX?

[Fourgearsticks]

Microsoft Flightsim?

[LRJim]

That's the one! Those pics look straight out of the simulator, too many days spent in front of a screen lol

[Hugh Jars]

The photos are out of a B737 technical reference app which I use for work. The MAX has only recently been added as a new variant, so the quality is a bit less than their usual standard.

[LRJim]

The photos are out of a B737 technical reference app which I use for work. The MAX has only recently been added as a new variant, so the quality is a bit less than their usual standard.Looks like they bought the graphics from Microsoft, I'm pretty sure it still is the simulator they train pilots on.
I had exactly the same graphics on my tablet I used for flight controls on FSX way back.
What do you use the app for? Flight briefing, mind refreshing, other?

Cheers Jim

[Hugh Jars]

It’s an interactive program on the aircraft systems which I (and thousands of B737 pilots) use to supplement the Boeing Vol 2 (and other) manuals into one simple information guide. Essentially it brings the information from various parts of the manuals together in one place. It was created by a pilot with many years experience (and extensive knowledge) on type.

Essentially, you tap on the item and it will bring up details and schematics of the related system, which makes it a lot easier to understand.

It’s also great to focus on particular systems in preparations for the dreaded recurrent sim check. An example follows. In the app, you just tap on any light or switch to get a full rundown of the item. Beats going from book to book to book [emoji846]

https://uploads.tapatalk-cdn.com/20181112/da5443a50efe9a54937a544587f1b8af.jpg

[LRJim]

It’s an interactive program on the aircraft systems which I (and thousands of B737 pilots) use to supplement the Boeing Vol 2 (and other) manuals into one simple information guide. Essentially it brings the information from various parts of the manuals together in one place. It was created by a pilot with many years experience (and extensive knowledge) on type.

Essentially, you tap on the item and it will bring up details and schematics of the related system, which makes it a lot easier to understand.

It’s also great to focus on particular systems in preparations for the dreaded recurrent sim check. An example follows. In the app, you just tap on any light or switch to get a full rundown of the item. Beats going from book to book to book [emoji846]

https://uploads.tapatalk-cdn.com/20181112/da5443a50efe9a54937a544587f1b8af.jpgInteresting, basically an interactive manual I really like it.
Looking at that next graphic it's definitely from the sim, it's used worldwide so dosnt surprise me that they would use the same graphics. It would definitely help new pilots stay familiar with the controls if all the graphics across the board are the same, I recognised it straight away and I've never stepped foot in B737.

Cheers Jim

[bob10]

Apparently, the correct procedure wasn't in the manual.

New Questions Swirl Over Boeing on Updated 737 Model that Crashed - The New York Times (https://www.nytimes.com/2018/11/13/world/asia/boeing-737-indonesia-crash.html?emc=edit_mbau_20181113&nl=morning-briefing-australia&nlid=8453466920181113&te=1)

[Hugh Jars]

Hi Bob,
I don’t have much info on the MCAS. Does it work through the stab trim, or is it a version of stick-push?

If it runs the stab trim, MCAS intervention might present as a runaway stabiliser (memory checklist for that). Stick push? - well that’s an entirely different animal......

[JDNSW]

Yes, it works through stab trim. See, for example, Indonesia 737 crash caused by “safety” feature change pilots weren’t told of | Ars Technica (https://arstechnica.com/information-technology/2018/11/indonesia-737-crash-caused-by-safety-feature-change-pilots-werent-told-of/)

[superquag]

We know the answer to the question... "How many 'hands-on' pilots are there in the Boing team that thought of, designed and signed off on that little add-on "Safety Feature"... the one that's lurking in the background even when the autopilot is turned off. ?
Or was it driven by the Sales Dept...

And it's not just airliners that are going overboard with computers gate-keeping between the Pilot and controlled surfaces.
Over on this side of the island, an iron ore train decided to go for a ride, while the driver was performing a routine (visual, out of cabin) carriage check. Cause of BHP runaway train | CEO says 'systems' - Australasian Mine Safety Journal (https://www.amsj.com.au/cause-of-bhp-runaway-train/)
and, How mining company BHP remotely derailed a runaway train - Create News (https://www.createdigital.org.au/bhp-remotely-derailed-runaway-train/)

My spy in the industry speculates that "they" may have been trialling a version of (Autonomous?) driverless train software, playing catch-up with another big company that has been successfully running theirs...
Not a Good Look when a software error takes over and buggers off with your expen$ive hardware !

Automobiles are not immune to 'automation mishaps', but being on the ground at a slower speed helps..[bigwhistle]
2002 Lexus LX 470 Anti-Skid Engage: My Lexus, without Warning, ... (https://www.2carpros.com/questions/lexus-lx-470-2002-lexus-lx-470-anti-skid-engage) and the same model here - Lx 470 2001 skid control malfunction:The vehicle suddenly - Fixya (http://www.fixya.com/cars/t8047680-lx_470_2001_skid_control)


Point is, it's a philosophy or 'Direction' of thinking that is driving this, - over-thinking, resulting in unexpected, obscure, UN-intended consequences.

[Hugh Jars]

Yes, it works through stab trim. See, for example, Indonesia 737 crash caused by “safety” feature change pilots weren’t told of | Ars Technica (https://arstechnica.com/information-technology/2018/11/indonesia-737-crash-caused-by-safety-feature-change-pilots-werent-told-of/)

I did some research today, and confIrmed it, JDNSW.

It looks like the MCAS drives the stab trim to meet its parameters - obviously nose down.

Boeing’s copout is the Runaway Stabiliser checklist. I admit that if I saw the stab trim running nose down for an unknown reason, I would be straight into that checklist.

It’s verging on criminal to include a totally new protection or system and not incorporate it into the manual suite for the people who operate this variant. It’s interesting that when Boeing introduced RCAS (roll protection) to the 737 fleet, there was a new section in the manuals, as well as a training module and a sequence in the simulator that needed to be completed. Someone seriously has dropped the ball here...

[JDNSW]

I get the impression that it was deliberate, so that no additional training was needed for pilots of earlier 737s.

This of course is separate from the issue of what exactly was the malfunction. The angle of attack sensor was replaced, so presumably not this. Sounds to me like it was a software error of some kind, either a coding error, or failure to design for some unusual set of parameters.

[bob10]

Hi Bob,
I don’t have much info on the MCAS. Does it work through the stab trim, or is it a version of stick-push?

If it runs the stab trim, MCAS intervention might present as a runaway stabiliser (memory checklist for that). Stick push? - well that’s an entirely different animal......


A very good question. Above my pay grade, I'm afraid.[bigsmile1]

[Rolly]

Interesting conundrum.
Here’s why, The runaway is a ‘Sensed’ Airspeed Unreliable(I.e low IAS approaching stall)........A completely different beast to ‘Runaway Stabilizer’.
I’m not conversant with this new system as I’ve only flown the classics and NG’s, where at least the runaway can be felt/seen in A/H and rapid descent but also recognized by trim wheel running continuously.
Does the trim wheel run continuously in the MAX with this failure? Because if not it would be hard to pick up(particularly close to the ground soon after T/O).
What’s also interesting is that this will only present itself when flying manually as the system is inactive/disarmed when A/P is engaged.

Also I’m gobsmacked that a manufacturer would integrate a system and make no mention within the FCOM?

[Hugh Jars]

Explainer: Unraveling the Boeing 737 MAX Lion Air crash | Reuters (https://reut.rs/2FnuCJN?fbclid=IwAR2OGMH943TuBGgbodcBPZg6E-RvWg5ImQi04QyVB6i4PEiPPd9bfFrp2G8)

So Rolly, it looks like it (MCAS) acts through the stab trim. They quote ‘two switches’ to override, I imagine these would be the stab trim cutout switches?

Wondering whether it would be input to the system similar to the Speed Trim?

[superquag]

.. and what these 'horses' are saying.
- Today, the most embarrassing reference on your CV; - would be the Boeing excutive(s) who signed off on including this feature... without telling the Pilots and Mechanics...[bigwhistle]

ALPA Seeks Clarity On Boeing 737 MAX Automated System Issues | MRO Network (https://www.mro-network.com/safety-regulatory/alpa-seeks-clarity-boeing-737-max-automated-system-issues?NL=AW-022&Issue=AW-022_20181116_AW-022_985&sfvc4enews=42&cl=article_1_b&utm_rid=CPEN1000002255446&utm_campaign=17430&utm_medium=email&elq2=0080d17892f64c82a5a1103905e66c14)

[Rolly]

Explainer: Unraveling the Boeing 737 MAX Lion Air crash | Reuters (https://reut.rs/2FnuCJN?fbclid=IwAR2OGMH943TuBGgbodcBPZg6E-RvWg5ImQi04QyVB6i4PEiPPd9bfFrp2G8)

So Rolly, it looks like it (MCAS) acts through the stab trim. They quote ‘two switches’ to override, I imagine these would be the stab trim cutout switches?

Wondering whether it would be input to the system similar to the Speed Trim?


Sorry Hugh,

I no longer operate the 737 so cannot determine the intricacies of MCAS however it seems logical that it would be an extension of speed trim

[bob10]

From the N.Y. Times.

In Lion Air Crash, Black Box Data Reveals Pilots’ Struggle to Regain Control - The New York Times (https://www.nytimes.com/2018/11/27/world/asia/indonesia-lion-air-crash-.html?emc=edit_na_20181127&nl=breaking-news&nlid=84534669ing-news&ref=cta)

From a blog.

Satcom Guru: First Look at JT610 Flight Data (https://www.satcom.guru/2018/11/first-look-at-jt610-flight-data.html)

[rick130]

If correct, how bloody frightening would that be. [emoji45]

[Rolly]

I heard an ex Engineer from Boeing discuss that the MCAS system was deliberately designed to remove control from the pilots and it could not be over ridden.
I’ll wait for the final report, however, if this is the case it is truly frightening.
Seems to go against Boeings philosophy, time will tell.