Jeju Air Flight Skids Off Runway at Muan Airport

wingnut771 said:
Doesn't that prove then that they turned off the wrong engine? You would think the designers would factor in both engines failing and the black boxes still working, but no.
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It should still have an APU and batteries
 
ponder said:
Will have to wait for the investigation to conclude.
Click to expand...
I've seen previous crash investigations where the black box is powered by the righthand engine and it stops recording when the engine fails.

5 stars to Boeing engineers.

From the evidence in this thread, I say that this is all down to pilot error IMHO.

Error 1: Pilot didn't continue to land after bird strike but decided on a go around. Raising landing gear and flaps is part of go around procedure iirc.

Error 2: Pilot turned off wrong engine. How do we know this? There was only 3 minutes between go around call and them making an extreme 180 degree turn and landing straight back onto runway halfway down the length at extreme angles. This is not what a go around looks like.

Error 3: Not factoring in the huge wall of death at the end of the runway. Apparently there was an open field next to the airport they could have landing in.
 
The APU in a commercial airliner is normally only activated & utilised once the aircraft gets to the terminal gate after landing, just before the main engines are powered down, so that continuous power (electrical & hydraulic, plus air-conditioning & lighting) is still available for the aircraft whilst the arrival passengers disembark, the cargo / luggage is off-loaded, the cleaning crew can then clean & prepare the cabin for the departure passengers, and the ground crew can also service the aircraft (waste / fresh water tanks and uploading of fuel) and then load the cargo / luggage for departure.

Once all the departure passengers have boarded the aircraft, the head count has been completed, and the cabin doors closed & secured (as well as the cargo hatches), and pushback from the gate has been done & engine No.1 (on the port / left side) has been started by using bleed air from the APU, and the engine generators / hydraulics brought online, then the APU can be shut down & the No.2 engine (on the right / starboard side) can then be started as well, prior to taxiing to the runway for departure.

The only reason an APU is started & brought back online during flight is usually when one (or more) of the main engine generators fails, so that redundancy can still be maintained.

That is why Capt Sully Sullenberger skipped the QRH procedure for a dual engine flameout, after multiple bird-strikes disabled both engines just after take-off, and immediately started the APU of his US Airways Airbus A320 & brought it online as the main engines wind-milled & spooled down (starting the APU was supposed to be a much later step in the QRH, but Sully realised he still needed electrical power for the A320's fly-by wire computer systems, and hydraulic power for other aircraft systems (like flight controls - elevators, ailerons, rudder & flaps).

This allowed him to still maintain directional control & safely guide the A320 to a successful splash-landing on the Hudson River.

In the JeJu B737-800 incident, it appears as if the damaged No.2 engine (right side) failed after the bird-strikes, taking its generator & hydraulic system offline, and in the chaos & confusion on the flight deck immediately following this, the crew mistakenly shut down the still fully operational No.1 engine (on the left), which meant that both main engine generators & hydraulic systems went offline. That's why the ADSB transponder also went offline - no power.

In the event of this happening, the ONLY power left on the aircraft was backup battery power for some critical flight instruments & a few electrical systems, like their radios.

However, the CVR & FDR are usually powered by the main electrical bus, and they would therefore have gone offline & stopped recording immediately when NO engine generators were supplying power anymore.

The pilots would have had to restart one of the engines OR the APU, and switch the main electrical bus back over to it, to restore full aircraft electrical power & reactivate power for the ADSB transponder & the FDR & CVR.

Unfortunately, at that critical juncture, they were just too low & slow to successfully initiate the normal go-around procedure, so had to immediately perform a 180 degree turn to try and do an emergency landing on the opposing end of the runway, before their remaining airspeed & altitude decayed into a stall.

It appears as if their CRM (Cockpit Resource Management) emergency procedures failed them completely, and it is entirely possible that they barely managed to restart one of the main engines just before they hit the runway (but had not switched over the electrical bus for that engine's generator) - that's why there were NO leading & trailing edge flaps deployed and the undercarriage was NOT extended after they had both been retracted as part of the normal procedures during the go-around - they simply ran out of time to do so.

It's also the reason that NO spoilers were deployed, as after being armed, they require a WOW (Weight On Wheels) electrical signal from sensors on the main landing gear struts to activate the spoilers as the wheels contact the runway & the aircraft weight is transferred over to the landing gear assemblies. If the undercarriage remains retracted, this is not possible.

Of course, this is all just conjecture on my part as an 'armchair aviator', but this is what I have been able to surmise from all the current info & analysis videos I have watched.

If anyone else wants to add to or correct my assumptions here, please feel free to do so - any additional input or info is welcomed.
 
Ivan Leon said:
The APU in a commercial airliner is normally only activated & utilised once the aircraft gets to the terminal gate after landing, just before the main engines are powered down, so that continuous power (electrical & hydraulic, plus air-conditioning & lighting) is still available for the aircraft whilst the arrival passengers disembark, the cargo / luggage is off-loaded, the cleaning crew can then clean & prepare the cabin for the departure passengers, and the ground crew can also service the aircraft (waste / fresh water tanks and uploading of fuel) and then load the cargo / luggage for departure.

Once all the departure passengers have boarded the aircraft, the head count has been completed, and the cabin doors closed & secured (as well as the cargo hatches), and pushback from the gate has been done & engine No.1 (on the port / left side) has been started by using bleed air from the APU, and the engine generators / hydraulics brought online, then the APU can be shut down & the No.2 engine (on the right / starboard side) can then be started as well, prior to taxiing to the runway for departure.

The only reason an APU is started & brought back online during flight is usually when one (or more) of the main engine generators fails, so that redundancy can still be maintained.

That is why Capt Sully Sullenberger skipped the QRH procedure for a dual engine flameout, after multiple bird-strikes disabled both engines just after take-off, and immediately started the APU of his US Airways Airbus A320 & brought it online as the main engines wind-milled & spooled down (starting the APU was supposed to be a much later step in the QRH, but Sully realised he still needed electrical power for the A320's fly-by wire computer systems, and hydraulic power for other aircraft systems (like flight controls - elevators, ailerons, rudder & flaps).

This allowed him to still maintain directional control & safely guide the A320 to a successful splash-landing on the Hudson River.

In the JeJu B737-800 incident, it appears as if the damaged No.2 engine (right side) failed after the bird-strikes, taking its generator & hydraulic system offline, and in the chaos & confusion on the flight deck immediately following this, the crew mistakenly shut down the still fully operational No.1 engine (on the left), which meant that both main engine generators & hydraulic systems went offline. That's why the ADSB transponder also went offline - no power.

In the event of this happening, the ONLY power left on the aircraft was backup battery power for some critical flight instruments & a few electrical systems, like their radios.

However, the CVR & FDR are usually powered by the main electrical bus, and they would therefore have gone offline & stopped recording immediately when NO engine generators were supplying power anymore.

The pilots would have had to restart one of the engines OR the APU, and switch the main electrical bus back over to it, to restore full aircraft electrical power & reactivate power for the ADSB transponder & the FDR & CVR.

Unfortunately, at that critical juncture, they were just too low & slow to successfully initiate the normal go-around procedure, so had to immediately perform a 180 degree turn to try and do an emergency landing on the opposing end of the runway, before their remaining airspeed & altitude decayed into a stall.

It appears as if their CRM (Cockpit Resource Management) emergency procedures failed them completely, and it is entirely possible that they barely managed to restart one of the main engines just before they hit the runway (but had not switched over the electrical bus for that engine's generator) - that's why there were NO leading & trailing edge flaps deployed and the undercarriage was NOT extended after they had both been retracted as part of the normal procedures during the go-around - they simply ran out of time to do so.

It's also the reason that NO spoilers were deployed, as after being armed, they require a WOW (Weight On Wheels) electrical signal from sensors on the main landing gear struts to activate the spoilers as the wheels contact the runway & the aircraft weight is transferred over to the landing gear assemblies. If the undercarriage remains retracted, this is not possible.

Of course, this is all just conjecture on my part as an 'armchair aviator', but this is what I have been able to surmise from all the current info & analysis videos I have watched.

If anyone else wants to add to or correct my assumptions here, please feel free to do so - any additional input or info is welcomed.
Click to expand...
100% this is what the investigation will say aswell IMHO.

This crash was all due to kak pilot flying, and I will put my kock on the block and say it was the captain flying, with junior officer too scared to say or do anything.
 
Ivan Leon said:
But Wait, There's More Shocking News!...

BREAKING NEWS! Both Black Boxes On JeJu Air Crash Plane STOPPED RECORDING 4 Minutes Before Crash - Maximus Aviation​

BREAKING NEWS! Both Black Boxes On the JuJu Air crash plane stopped recording 4 Minutes Before the Crash landing while the plane was STILL in the Air. South Korea has known this since January 4, just revealing it now a week later.

Click to expand...
errr ... HOW?!?

it's not like they come with pause / stop buttons, this sounds like sensationalist BS tbh
 
Hopefully there's NO confusion regarding the names of the pilots this time around - unlike with the Asiana Airlines Boeing 777 (Flight 214) crash at San Francisco International Airport in July 2013 - that was an embarrassing incident for the NTSB... ;)

1736606679707.png

www.hollywoodreporter.com

TV Station Falsely Reports Names of Asiana Flight Pilots

UPDATE: An NTSB summer intern confirmed the fake names to the Bay Area media outlet.
www.hollywoodreporter.com www.hollywoodreporter.com

 
Ivan Leon said:
Read my detailed post - #127 above - for why the ADSB, FDR & CVR all went offline at the SAME time - 4 minutes BEFORE the crash... ;)
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great, except ...

most videos and analysts of said videos point out the one engine was still running at touch down given the plume behind it, maybe not generating much thrust, but certainly electricity at the very least, they point to the fact that the pilot clearly seemed to have control over navigation / direction at that point as an indication that hydraulics / electronics / avionics were up and running

also, black boxes tend to run on battery backup as mandated by law since 2010, not sure of this airplane's exact specification, but something seems way off if a) it had battery backup and b) one engine was still running in any sort of capacity

I'd sooner believe the last 4 minutes were deleted or is intentionally being withheld than it not being recorded
 
NarrowBandFtw said:
great, except ...

most videos and analysts of said videos point out the one engine was still running at touch down given the plume behind it, maybe not generating much thrust, but certainly electricity at the very least, they point to the fact that the pilot clearly seemed to have control over navigation / direction at that point as an indication that hydraulics / electronics / avionics were up and running

also, black boxes tend to run on battery backup as mandated by law since 2010, not sure of this airplane's exact specification, but something seems way off if a) it had battery backup and b) one engine was still running in any sort of capacity

I'd sooner believe the last 4 minutes were deleted or is intentionally being withheld than it not being recorded
Click to expand...

From my post #127...

In the JeJu B737-800 incident, it appears as if the damaged No.2 engine (right side) failed after the bird-strikes, taking its generator & hydraulic system offline, and in the chaos & confusion on the flight deck immediately following this, the crew mistakenly shut down the still fully operational No.1 engine (on the left), which meant that both main engine generators & hydraulic systems went offline. That's why the ADSB transponder also went offline - no power.

In the event of this happening, the ONLY power left on the aircraft was backup battery power for some critical flight instruments & a few electrical systems, like their radios.
Click to expand...

However, the CVR & FDR are usually powered by the main electrical bus, and they would therefore have gone offline & stopped recording immediately when NO engine generators were supplying power anymore.

The pilots would have had to restart one of the engines OR the APU, and switch the main electrical bus back over to it, to restore full aircraft electrical power & reactivate power for the ADSB transponder & the FDR & CVR.
Click to expand...

It appears as if their CRM (Cockpit Resource Management) emergency procedures failed them completely, and it is entirely possible that they barely managed to restart one of the main engines just before they hit the runway (but had not switched over the electrical bus for that engine's generator) - that's why there were NO leading & trailing edge flaps deployed and the undercarriage was NOT extended after they had both been retracted as part of the normal procedures during the go-around - they simply ran out of time to do so.
Click to expand...
 
Sorry am I understanding this right, both flight and voice recorders both stopped working exactly 4 mins before the crash...?
 
Aircraft electrical systems are very complex - there are a number of different AC & DC electrical bus circuits - and when one generator fails - there is a procedure for switching over to one of the other electrical bus circuits to maintain electrical power between the other generator/s, the APU & battery backup - I doubt that the flight crew of the Jeju B737-800 had time to worry about that whilst they were fighting to keep the aircraft airborne & also doing the 180 degree turn - too many QRH procedures to go through & follow, and WAY TOO LITTLE TIME to do all of that as well...
 
NarrowBandFtw said:
none of which speaks to legally mandated battery backup for flight recorders ...
Click to expand...
The legally mandated 'battery backup' for the CVR & FDR are for their ELT's - Emergency Locator Transmitters - they provide a weak radio ping signal for up to 28 days after a crash, if the CVR or FDR are buried under soil or water, so they can be located & recovered successfully. Their battery backup is NOT for recording purposes - that power is provided by the aircraft's electrical system - that's why their circuit breakers need to be popped if there's been an in-flight incident and the aircraft lands safely, so that the FDR & CVR don't over-write their data - the crew of the Alaska Airlines B737 Max 8 that lost a door panel forgot to pop the circuit breakers after they landed, started the APU and shut down the two engines so that emergency first responders could deal with the injured passengers & crew inside the aircraft - so the NTSB couldn't retrieve the CVR data for analysis as it has a 2-hour over-write loop... the FDR has a much longer data storage capacity, so its data could still be retrieved...
 
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TV series like Air Crash Investigation (on Disney+) and Mayday: Air Disaster (YouTube) have many episodes where the issues regarding the CVR & FDR are detailed - you should check them out - they are very informative... ;)
 
Ivan Leon said:
Aircraft electrical systems are very complex - there are a number of different AC & DC electrical bus circuits - and when one generator fails - there is a procedure for switching over to one of the other electrical bus circuits to maintain electrical power between the other generator/s, the APU & battery backup - I doubt that the flight crew of the Jeju B737-800 had time to worry about that whilst they were fighting to keep the aircraft airborne & also doing the 180 degree turn - too many QRH procedures to go through & follow, and WAY TOO LITTLE TIME to do all of that as well...
Click to expand...
All else fails you can deploy the RAT (Ram Air Turbine) assuming airspeed is adequate I suppose. That was the answer I got from an Emirates captain when I asked him about power failures. All will be revealed in due course.
 
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