China Eastern 737-800 MU5735 accident March 2022

[FlightDetent]

Originally Posted by Sailvi767

I still find it interesting the Chinese government has offered no explanation for a 31,000 hour former CA flying as a FO on the trip.

It hardly fits the calendar, does it? We tried to see how but actually it could work. Still expecting some findings if rigorous checking is perfomed, not that the world would learn about.

Assuming the senior ex-captain was a party poster icon, together with years served and higher age that gets you ahead and beyond everyone else. Keep in mind flight hours make money... Part 121 limits were 1000 annualy bfore 2020 and SIM on top of that yet that might be a part of the listed total experience, including teaching time.

Qatari and Emirates are squeezing 1400 hours from the boys, before factoring. If you're the top-brass surely you can do 8 hours SIM instruction for weeks without setting a foot in the pleasurebox, sharing the income with the junior TRI who would do the actual work .... you get my drift. Seen similar years after the deceased's prime time.

[WideScreen]

Originally Posted by FlightDetent

......Online sources suggest before the crash around 40 of the -800 were in service compared to 60 stored, accompanied by 25ish -700 all in active service.

I checked that for you. According FR24, all but one of the 109 B737-800 were in regular commercial service in the 2 weeks before 21/3/2022.
The same applies for the B737-700.

Originally Posted by FlightDetent

Whereas the single-aisle Airbus fleet had 300 active planes flying, above those parked.

I checked that for you. According FR24, MU does have 290 A319/320/321 airplanes.

Originally Posted by FlightDetent

40+30+400 = 470
470 / 3 (optimistic, double the real today's sector count) = around 15 planes needed and 320 left unused beyond those mothballed.

Keeping the 800s grounded altogether, with 40 hulls, is an irreleveant decision that costs nothing and has some marketing potential for damage control.

Given your starting figures are off, I think, the conclusion has become wobbly too.

[FlightDetent]

Perfect, thanks for straightening those.

I usually go here: https://www.planespotters.net/airlin...stern-Airlines or here: https://www.airfleets.net/ageflotte/...20Airlines.htm but landed in a different place this time and while it looked similar, it was neither of them. Used Bing, maybe that's why.

Not sure how to obtain numbers from FR24 but if they saw them fly surely they did. I honestly meant 150 planes needed not 15.

I checked that for you. According FR24, MU does have 290 A319/320/321 airplanes.

Please have a second look: https://www.flightradar24.com/data/a...s/mu-ces/fleet, I see 361 single-aisle Airbii not 290 (my original source suggested 290 flying and 65 stored before the crash).

But you're right, adding 40+30+300 is not 470 now I scared myself from reading that post again. Should have resulted in 125 required to fly the schedule.

These guys https://www.planespotters.net/airlin...stern-Airlines indicate 106 pcs of -800 grounded alongside additional 163 A32x(n)s. Supports my suggestion CEAir has parked significantly more frames for commercial reasons than induced by the reaction to accident.

[dbenj]

Originally Posted by Sailvi767

I still find it interesting the Chinese government has offered no explanation for a 31,000 hour former CA flying as a FO on the trip.

I also find it interesting that the "aircraft part" discovered several miles from the crash site has not been confirmed to either be part of or not part of MU5735.

[FlightDetent]

CAAC data set:




Assuming 1900 domestic sectors for the last week, and with a conservative 3 daily legs per hull, the need is only for 90 airplanes. With all the grounded -800 already set aside they still have, in addition,

361x n.b. airbus
40x 737-700
55x A330

= 450 planes to fly the schedule (1/5 already seen in post #412)

[BuzzBox]

Originally Posted by WideScreen

I checked for you on FR24, though, according FR24, only 5 out of the 105 MU B737-800 are SCHEDULED to fly on 18/4 or 19/4. And that is roughly the same qty as was scheduled for the same dates, a week ago. Only the MU B737-700 do fly. So debunked.

The following SCMP article claims China Eastern resumed -800 operations over the weekend:
https://www.scmp.com/news/china/poli...er-march-crash

https://www.flightradar24.com/data/f...u5843#2b851efa

[tdracer]

Same with Rueters:

BEIJING (Reuters) -China Eastern Airlines has started putting its Boeing 737-800 jetliners back in use for commercial flights less than a month since a crash killed 132 people and led the company to ground 223 of the aircraft, the carrier said on Sunday.
The airline said it had conducted systematic tests, structural checkups and verified airworthiness data for each of the aircraft, and that test flights would be carried out on all planes before they resumed commercial services.
Boeing 737-800 planes with registration numbers close to the one that crashed on March 21 are still undergoing maintenance checks and evaluation, the company told Reuters in a statement.
Flightradar24 data showed earlier in the day that China Eastern flight MU5843, operated by a three-year-old Boeing 737-800 aircraft, took off from the southwestern city of Kunming at 09:58 a.m. (0158 GMT) on Sunday and landed at 11:03 a.m. in Chengdu, also in southwestern China.
That aircraft, which completed a test flight on Saturday, later returned back to Kunming, according to Flightradar24.

Given the minimal differences between a 737-700 and -800, the grounding of only the -800 fleet was more symbolic than any real concern over the airworthiness of the 737-800 fleet.

[Carbon Bootprint]

China Eastern resumes 737-800 service

From today's Wall Street Journal:

HONG KONG—China Eastern Airlines said it has resumed passenger flights of its Boeing 737-800 model aircraft after grounding the planes for nearly a month, following a crash of one of the planes that killed all 132 people on board.China Eastern said on Monday that while the airline’s Boeing 737-800 planes have resumed operations, it is still inspecting and conducting assessments on a batch of the 737-800 aircraft that were manufactured around the same time as the plane that had crashed.China Eastern’s grounding of the planes was an emergency measure to run system tests on each of the 737-800 aircraft to examine airworthiness data, a representative from the airline said. The company is also conducting flight tests for 737-800 planes, the representative said.

The article notes the 737-MAX is still grounded in China.

Full article.

[WideScreen]

Checking further, today:
B-209L did do a test flight on 16/4 and a commercial return leg on 17/4.
B-209M did do a test flight on 17/4 and a commercial return leg on 18/4.

All the rest still grounded, with 4-5 B737-800 scheduled to fly on 19/4.

So, "slowly" "ungrounding".

[WideScreen]

Originally Posted by tdracer

Same with Rueters:

Given the minimal differences between a 737-700 and -800, the grounding of only the -800 fleet was more symbolic than any real concern over the airworthiness of the 737-800 fleet.

Yep, that is/was my surprise too. Indeed, maybe symbolic, or just a way to "claim" damage from Boeing, in case the accident turns out to be something with the airplane.

You're the Boeing expert: What are the differences between the B737-700 and B737-800 ? The length, the wiring around the extension locations. More ?

[Lonewolf_50]

Originally Posted by WideScreen

What are the differences between the B737-700 and B737-800 ? The length, the wiring around the extension locations. More ?

You may find this useful as a starting point.

[DaveReidUK]

Or Chris Brady's superlative Boeing 737 Technical Site.

[Arrowhead]

Pure speculation... cockpit crew member suicide.

Evidence: (i) lack of updates/general silence by CAAC, (ii) CES has put B738s back in service now (but took ages with Max's), (iii) Shenzhen stock market has tumbled 30% (and most Chinese investors borrow to invest in stocks), (iv) Evergrande and Chinese property generally bankrupt, (v) no alert to ATC of any kind despite 3 pilots normally in cockpit in China, (vi) extreme pitch, (vii) little evidence of gradual disintegration of control/fight back, (viii) rumors of FO suicide denied already by Wu Shijie, (ix) below ICAO standard flight time/rest limitations, and general management disinterest in mental health, in mainland China (x) general high level of safety and maintenance in China (ie doubtful maintenance problem, and B738 already proven), (xi) time of day of crash/weather - since most aircraft accidents are very early morning flights, or during the night, and/or in foul weather, (xii) punishment (not support and self-improvement) culture in mainland China, coupled with crazy experienced FO still in right seat

If I'm right, expect a cover up. The above are mostly China-specific problems. They cant blame it on the aircraft (for public confidence reasons), so they will have to declare no conclusions due recorders broken. Meanwhile there would be a very quiet edict from the CAAC to check the mental health of pilots (which probably wouldnt then happen) and perhaps a change to meet ICAO FTLs.

[spornrad]

https://news.cgtn.com/news/2022-04-1...jmo/index.html
A week ago the Ch news were already mentioning
"the Civil Aviation Administration of China said... it was vital that more emphasis is placed on assessing the psychological status of air crews."
Pretty clear statement as to the cause of this crash imho.

[tdracer]

Originally Posted by WideScreen

You're the Boeing expert: What are the differences between the B737-700 and B737-800 ? The length, the wiring around the extension locations. More ?

I'm not really an expert on the 737 (spent minimal time working it), but if you look at the 737NG, the -600, -700, -800, and -900, the systems and flight controls are nearly identical (aside from different wiring and control cable lengths). Similarly, engine wise, pretty much everything under the wing is the same aside from the engine rating plug. There are obviously structural differences with the different fuselage lengths and the different gross weights. The wing areas are common, although again structural differences for the different weights (mainly different thickness of the various materials). There is also some sort of structural difference going between the -700 and -800 wings - I don't know details, but when they started adding winglets they had to make minimal changes to the -800 (and -900) wings, much more major changes to the -700 wings (not sure if they ever put winglets on the -600 - not many were ever built).

[andrasz]

Originally Posted by tdracer

There is also some sort of structural difference going between the -700 and -800 wings - I don't know details...

This is not a difference between the -700/-800, it goes across the range. Boeing introduced blended winglets for NGs as BFE for -700 upwards (not the -600) sometime in the late 2000s, from thereon all aircraft coming off the line had a provisioned wing which allowed rapid installation (2 days as opposed to 3/4 days on a non-provsioned wing). Many more -700 were built before this modification, effective from L/N 1545 on the -700 and L/N 778 on the -800.

[DraggieDriver]

Originally Posted by WideScreen

You're the Boeing expert: What are the differences between the B737-700 and B737-800 ? The length, the wiring around the extension locations. More ?

This article indicates B737-700 IGW would have several features of the -800, "will use a 737-700 fuselage, combined with the strengthened wing, centre body and landing gear of the larger -800."
https://www.flightglobal.com/boeing-.../18470.article

[tdracer]

Originally Posted by andrasz

This is not a difference between the -700/-800, it goes across the range. Boeing introduced blended winglets for NGs as BFE for -700 upwards (not the -600) sometime in the late 2000s, from thereon all aircraft coming off the line had a provisioned wing which allowed rapid installation (2 days as opposed to 3/4 days on a non-provsioned wing). Many more -700 were built before this modification, effective from L/N 1545 on the -700 and L/N 778 on the -800.

Again, I don't know details, but what I remember is that it was much cheaper and easier to retrofit the -800 with the blended winglets than it was the -700 due to 'structural differences'. I assumed that meant more than just gage thicknesses, but I could be wrong.
Then again, it must not have been that much more difficult, since I rarely see any 737NG without winglets.

[A0283]

@tdracer - Saving a claimed few percent WITH winglets does makes things 'easy' ... doesn't it

[172_driver]

It's been a while now but I seem to remember a speed restriction for max speedbrake on some of our -700s that had been retrofitted with winglets, but not on all of them.