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US refuses to ground Boeing 737 Max

bbc.com

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Re: US refuses to ground Boeing 737 Max

#331

Post by kickopotomus »

buboard wrote: post #313
kickopotomus wrote: post #312

Earlier quoted context omitted.

Yes, it is. The 737 NG (700 series, 800 series, etc) has a hull loss rate of 0.27 per million departures[0]. I am having difficulty finding the exact number of departures for the MAX but 737s average about 3-5 departures per day[1]. Only 350 MAXs have been delivered and the first one was delivered on May 6, 2017[2] (676 days ago). So even being generous and supposing that all 350 aircraft were delivered exactly on Ma…

the question is if this difference is statistically significant

You are taking a commercial flight. You have the choice between 2 different aircraft which are essentially identical but you are more than 50 times more likely to crash in one of them. Which do you take?

EDIT: I have learned that I was far too generous with the flight numbers. The MAX series has only logged ~150K flights. Therefore it's hull loss rate is roughly 13.33 per million making it almost 50 times more dangerous than the NG line.

Yes, the difference is statistically significant.

Re: US refuses to ground Boeing 737 Max

#332

Post by jhayward »

CaptainZapp wrote: post #242
jhayward wrote: post #217

Earlier quoted context omitted.

We don't know which pilot was the flying pilot on this takeoff.

That should not be relevant at all. During the critical phases of flying both pilots will be engaged with the operation. While it's true that the first officer may execute the take-off the captain will be at the controls, alert and ready to intervene at any time. Later during cruising the responsibilities may be split. For example: The captain may deal with administrative stuff while the first officer is actually fly…

It is relevant because MCAS is tied to the AOA sensor on the side of the active flight computer. Even if the Captain intervened, he may not have thought to switch flight computers to rule out a malfunctioning AOA sensor.

I'm well aware of cockpit procedure; my brother is a 30-year captain, now retired and our family has been flying since before I was born. One of my earliest memories is of using the barf bag in a 172 while my father was shooting landings.

Re: US refuses to ground Boeing 737 Max

#333

Post by jhayward »

sangnoir wrote: post #250
jhayward wrote: post #217

Earlier quoted context omitted.

We don't know which pilot was the flying pilot on this takeoff.

Let's assume it was the FO. Do you think the captain was just watching it all play out as the plane lost altitude?

You are aware of the MCAS being tied to the single sensor on the side of the active flight computer?

Re: US refuses to ground Boeing 737 Max

#334

Post by wallace_f »

wallace_f wrote: post #87
crubier wrote: post #78

Earlier quoted context omitted.

Sure, then let's fly other unsafe planes types as well to save money, and hand the benefits to the poor! Except, in which universe do airlines hands out their revenue to the poor ?

That's not the point. The point is that the comparison between people's lives and money is invalid. Because scarce resources are a real thing, there necessarily should be a value to life, otherwise you are just ignoring reality.

I like how people downvote this, yet when stepping over homeless people in SV think "I only make $100,000+, and I need every bit of it, even if $20 could drastically improve this human's welfare.

Then when they board a flight on their own: "millions is not too much to spare! No cost is too great for my life!"

It is a double standard.

Re: US refuses to ground Boeing 737 Max

#335

Post by rorykoehler »

whack wrote: post #311
rorykoehler wrote: post #208

Earlier quoted context omitted.

If cars are considered defective they are recalled. Happens often. Your comment is shockingly tone deaf.

Whether you choose to categorize a death being caused by "defects" or "user error" is ultimately irrelevant. Any system that's prone by design to user error should be considered equally defective. Even with the two ambiguous incidents on Boeing 737, they are still far safer than the vehicles that people choose to ride everyday for pleasure. I will never ride a motorcycle myself, but would hate to see them banned nati…

If the brakes on your car failed one in every 100k engagements would you feel safe driving your car? Anyways news just in. Sanity prevailed. https://www.bbc.com/news/business-47562727

Re: US refuses to ground Boeing 737 Max

#336

Post by av_throwaway_20 »

improbable22 wrote: post #194
av_throwaway_19 wrote: post #68

Earlier quoted context omitted.

It isn't just the FAA and Boeing. Where I work many of us have a "common type rating" between the A330 and A350 (-900 and -1000). While I commend Airbus for making them similar they are in no way common enough to justify the minuscule training course. Flying the A350 you get lots of brilliant features like brake-to-vacate, auto wing leveling during a crosswind landing (when you de-crab), differential flap setting in…

I'm curious to hear more. I understand that common type means that much less training is required to fly the new plane for the first time. But once you are trained for several kinds of aircraft, does the airline treat them differently? For instance, will they happily schedule you to fly anything you are type-certified for, tomorrow? Or do they keep you on one type for a block of time, perhaps with a simulator day to…

They treat them as the same type with only a few conditions regarding recency. For example, out of three simulator checks you need to do one in each type (330/330/350 or 350/350/330 for example).

Also need to do at least one takeoff and landing in each (in addition to the three takeoffs and landings in 90 days), in 60 days.

Otherwise they treat them the same. I routinely get rostered to fly one type on a short sector, get in, change aircraft to the other type and fly it somewhere else.

Literally only an hour to adapt to the other type.

Re: US refuses to ground Boeing 737 Max

#337

Post by av_throwaway_20 »

sib wrote: post #227
poof131 wrote: post #131

Earlier quoted context omitted.

> My company's error rates have increased on the "common fleet" by almost triple. That is Terrifying. It seems like the FAA has optimized for allowing the Manufacturers and Airlines to streamline changes and operations while slowly letting safety deteriorate. Perhaps these accidents will force what seems like a needed change in type ratings.

From GP's comment, it appears that s/he is not referring to the FAA. "It isn't just the FAA and Boeing."

It isn't the FAA.

It's a country in Asia to give you a hint. If you google for the fleets mentioned you can probably work it out!

Re: US refuses to ground Boeing 737 Max

#338

Post by av_throwaway_20 »

xkcd-sucks wrote: post #238
av_throwaway_19 wrote: post #68

Earlier quoted context omitted.

It isn't just the FAA and Boeing. Where I work many of us have a "common type rating" between the A330 and A350 (-900 and -1000). While I commend Airbus for making them similar they are in no way common enough to justify the minuscule training course. Flying the A350 you get lots of brilliant features like brake-to-vacate, auto wing leveling during a crosswind landing (when you de-crab), differential flap setting in…

Temporary Abnormal Behaviors, now there is a nice piece of jargon

My favorite: Controlled Sunlight Blocking System (CSBS)

aka: window shades

Re: US refuses to ground Boeing 737 Max

#339

Post by av_throwaway_20 »

raverbashing wrote: post #158
av_throwaway_19 wrote: post #68

Earlier quoted context omitted.

It isn't just the FAA and Boeing. Where I work many of us have a "common type rating" between the A330 and A350 (-900 and -1000). While I commend Airbus for making them similar they are in no way common enough to justify the minuscule training course. Flying the A350 you get lots of brilliant features like brake-to-vacate, auto wing leveling during a crosswind landing (when you de-crab), differential flap setting in…

> However, coming back to the 330 after lots of 350 flying it's very easy to forget just what you have and don't have. Yeah that seems to be an important issue. You easily "get used" to a feature and I wouldn't be surprised if a pilot used to the 350 got in a bad situation on the 330. Are those error rates taken from FOQA? And is the company raising the issue?

They come from a regular internal audit and QAR data. They can set triggers on certain items. For example, certain configurations (or lack of) at certain altitudes can trigger a data point for the safety department.

Re: US refuses to ground Boeing 737 Max

#340

Post by waste_monk »

tialaramex wrote: post #186
agumonkey wrote: post #159

Earlier quoted context omitted.

I'm not sure we understood each other. I understand aviation is heavily monitored by the field, but maybe only a few (when fatal or grave) sample of incidents gets to the public eye. Unless walkingolof is also in the field and by 'track record' he meant even 'up to the slightest faults'.

All aviation accidents are reportable in most civilised countries, and the reports will be public. For an airliner (which these are) they'll invariably make the news. For little prop planes in GA nobody cares unless someone died. Take an example from Ireland, an island near me. A crew screwed up and typed the wrong temperature into the computer, which calculated take-off thrust based on higher density air than was re…

>A crew screwed up and typed the wrong temperature into the computer, which calculated take-off thrust based on higher density air than was reality

May I ask, why does the plane not have an external temperature sensor able to automatically input this data?

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