Boeing 747 zletel s steze

Air Tractorji tokrat pomagajo nad Žerjavom pri Črni na Koroškem.

US regulator flagged fuel switch issues in 2018, what Air India told probe team: ‘Not mandatory’

In 2018, US FAA issued bulletin on potential problems with fuel switch locking mechanism on Boeing aircraft; it prevents inadvertent movement of switches

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FAA NM-18-33 https://static-gi.asianetnews.com/common/01jzyjc6pj2t1cn4tqaax07ac4/easa-sib-nm-18-33-1.pdf

So notri navedeni (med drugimi):

Model 787-8, -9, and -10 airplanes;

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vsi:

This Special Airworthiness Information Bulletin (SAIB) is to advise registered owners and operators
of The Boeing Company Model 717-200 airplanes; Model 737-700, -700C, -800, and -900ER
series airplanes; Model 737-8 and -9 airplanes; Model 747-400, -400D, -400F, -8, and -8F series
airplanes; Model 757-200, -200CB, -200PF, and -300 series airplanes; Model 767-200, -300, -
300F, -400ER, and -2C series airplanes; Model 787-8, -9, and -10 airplanes; Model MD-11 and
MD-11F airplanes; and Model MD-90-30 airplanes of the potential for disengagement of the fuel
control switch locking feature.

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Če ni bilo namerno, potem je nekdo od dvojice v pilotski kabini nenamerno in nevede premaknil obe stikali na off.

stikali za gorivo na B787:


Kot kaže posnetek ju ne moreš mimogrede in nevede premakniti (vsaj ta dva na posnetku).
Potegneš gor (nach oben ziehen), šele nato lahko premakneš.

Poleg tega premik stikala povzroči en tipičen zvok (namerno narejeno tako), ki se ga sliši na CVR.

Kronologija, kopiram iz yt komentarja
---
From the initial preliminary investigation report by the Aircraft Accident Investigation Bureau (AAI):

08:08:39 Air India VT-ANB takes off. Flaps are set to 5 degrees.

08:08:41 The Ram Air Turbine (RAT) deploys.

08:08:42 The maximum recorded airspeed of 180 knots is reached.

08:08:43 Fuel shutoff switch for engine 1 changes from RUN to CUTOFF.
08:08:44 Fuel shutoff switch for engine 2 changes from RUN to CUTOFF.
Fuel supply to the engines is interrupted, engine power decreases.

08:08:52 Switch for engine 1 changes back from CUTOFF to RUN.

08:08:54 The APU intake flap begins to open (APU stands for Auxiliary Power Unit).

08:08:56 Switch for engine 2 changes from CUTOFF to RUN.
The exhaust gas temperature of both engines increases, indicating a possible reignition.

08:09:11 Recording stops.
---


The Ram Air Turbine (RAT) se je avtomatsko vklopila/sprožila (znak da ni drugega pogona; sudden and complete loss of power), preden sta bila fuel stikali na off !

Kronologija, kopirana iz yt komentarja je BS.

Tukaj je: Preliminary Report Accident involving Air India’s B787-8 aircraft bearing registration VT-ANB from "India Aircraft Accident Investigation Bureau"

iz pdf-ja
#14

The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42
UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned
from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1
and N2 began to decrease from their take-off values as the fuel supply to the engines was cut
off.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so.

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As per the EAFR data both engines N2 values passed below minimum idle speed, and the
RAT hydraulic pump began supplying hydraulic power at about 08:08:47 UTC.

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Na strani 14, 15 je celoten timeline, in kot kaže je tam napisano malo drugače, nekako tako:

tl;dr povzetek:

Prvo stikali na CUTOFF, nato RAT

At 08:08:42 UTC, both fuel cutoff switches transitioned from RUN to CUTOFF, one second apart

Engine power (N1/N2) began declining due to fuel starvation

CVR recorded a pilot asking, “Why did you cut off?” and the other responding, “I did not”

RAT (Ram Air Turbine) deployed at 08:08:47 UTC to restore hydraulic power

Attempted Recovery​

• At 08:08:52 UTC: Engine 1 fuel control switch returned to RUN
• At 08:08:56 UTC: Engine 2 switch also returned to RUN
• FADEC attempted auto-relight: Engine 1 began recovering; Engine 2 failed to stabilize
• EGT rise confirmed attempted relight on both engines
• Mayday call transmitted at 08:09:05 UTC; final data recorded at 08:09:11 UTC
• Aircraft crashed into residential structures beyond airport perimeter

Malo je kot kaže zmanjkalo časa/višine, da bi se rešili in proper zagnali motorja.

LMM pomoč (https://lmarena.ai , chatgpt-4o-latest-20250326) :

input:

explain
FADEC attempted auto-relight: Engine 1 began recovering; Engine 2 failed to stabilize

EGT rise confirmed attempted relight on both engines

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output:
This statement relates to a jet aircraft with two engines, and it's describing an in-flight engine malfunction and attempted recovery using **FADEC (Full Authority Digital Engine Control)**. Let me break it down clearly:

---

### **Statement:**
>**"FADEC attempted auto-relight: Engine 1 began recovering; Engine 2 failed to stabilize"**

#### What it means:

- **FADEC attempted auto-relight:**
The aircraft’s **digital engine control system (FADEC)** detected an engine flameout (loss of combustion) and **automatically attempted to restart** both engines without pilot input, as it's programmed to do in certain failure conditions.

- **Engine 1 began recovering:**
Engine 1 responded to the auto-relight — combustion was likely re-established, and the engine began returning to normal parameters (e.g., RPM, EGT, fuel flow, etc.).

- **Engine 2 failed to stabilize:**
Engine 2 may have briefly restarted or shown signs of relight (e.g., an EGT rise), **but it didn’t fully recover** to a stable operating condition. It could not reach or maintain normal idle/stable thrust values.

---

### **Second statement:**
>**"EGT rise confirmed attempted relight on both engines"**

#### What it means:

- **EGT (Exhaust Gas Temperature)** is one of the key indicators monitored during engine start or relight attempts.

- A **rise in EGT** during the relight attempt confirms that **fuel was introduced** and **ignition occurred**, as combustion causes EGT to spike.

- So, the rise in EGT confirms that **both engines tried to relight**, even if only one of them (Engine 1) succeeded.

---

### **Summary:**

- The FADEC system tried to automatically restart both engines after detecting a flameout or power loss.
- The relight procedure was successful for **Engine 1**, which started to function normally again.
- However, **Engine 2** did not fully recover, even though it showed initial signs of ignition (via EGT rise).

This type of information is typically part of an emergency event log or incident report and would be crucial in diagnosing the root cause of the engine failure and partial recovery.

Let me know if you’d like a visual diagram or further explanation!




LMM scenarij 1:

How long does it take for relight B787-8 engine at FL320 (9754 m) ? (and speed Mach 0.84 ), če nekdo prestavi fuel stikali na off​

Typical in-flight windmill relight on a modern high-bypass turbofan engine (like the GEnx-1B on the 787) takes:

➤ 30 to 60 seconds for each engine​

• If automatic relight succeeds on both engines, the engines will return to idle thrust in under a minute.
• FADEC attempts multiple relights depending on programming logic and conditions.

It typically takes between 30 and 60 seconds for each engine to become fully functional again (idle thrust) following an accidental shutdown and FADEC-initiated in-flight auto-relight on the Boeing 787-8, assuming no engine damage or limit exceedances.



LMM scenarij 2, kako je bilo:
*

• Reached max speed of 180 knots at 08:08:42 UTC

At 200 meters altitude (and speed 180 knots* oz 333 km/h), FADEC auto-relight will be too late to save the aircraft. The engines will not be functional in time.

This would almost certainly result in loss of the aircraft, unless in extraordinary circumstances (e.g. extremely lucky landing spot nearby and perfect pilot response).


LMM scenarij 3 (minimalna teoretična višina/hitrost za tak tip letala):
ne bom celotnega odgovora lepil:

## FINAL ANSWER:

### Minimum parameters for theoretical engine recovery:

| Parameter | Value |
|------------------------|------------------------------------------|
| **Altitude (minimum)** | **1,500–2,000 feet AGL** | oz. (457.2-609.6m)
| **Airspeed (minimum)** | **≥180 knots** (absolute minimum), **≥250 knots preferred** | oz. 463 km/h
| **Relight success time** | ~30–60 seconds |
| **Descent during relight** | ~1,100–1,800 feet |
| **Thrust restored by** | **~45 seconds after engine shutdown**, if ideal conditions |


### Warning:
This is a **best-case theoretical scenario** assuming:
- No engine damage
- No mechanical faults or FADEC inhibit logic
- Correct engine windmilling RPM achieved
- No pilot delay
- Engines remain within relight envelope (temperature, RPM, etc)

In real emergencies like **dual flameout (e.g. Air Transat 236, BA038, birds-strike failures)**, outcomes vary based on weather, aircraft configuration, and luck.

---

## Real-World Use Case:
- **Below ~2,000 ft AGL**, complete flameout (both engines off) means you’re in **forced landing territory**.
- Any delayed relight nearly guarantees inability to stabilize engines **before ground contact**.
- At **3,000 ft (915 m) AGL & 250 KIAS (463 km/h) **, the aircraft has **~1 minute of glide time** — enough for FADEC to complete auto-relight under ideal conditions.

Uporabnik Ytbnd je napisal:

stikali za gorivo na B787:

Kot kaže posnetek ju ne moreš mimogrede in nevede premakniti (vsaj ta dva na posnetku).
Potegneš gor (nach oben ziehen), šele nato lahko premakneš.

Poleg tega premik stikala povzroči en tipičen zvok (namerno narejeno tako), ki se ga sliši na CVR.

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Inspect the locking feature of the fuel control switch to ensure its engagement. While the airplane is on the ground, check whether the fuel control switch can be moved between the two positions without lifting up the switch. If the switch can be moved without lifting it up, the locking feature has been disengaged and the switch should be replaced at the earliest opportunity

Uporabnik erikson je napisal:

Air Tractorji tokrat pomagajo nad Žerjavom pri Črni na Koroškem.

https://www.facebook.com/video.php?v=584590257827307

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Moraš imeti kar velike "balinčke"

Tale lepo povzema situacijo. Nakazuje se velika možnost samomora enega od pilotov.

Uporabnik mosseero je napisal:

Tale lepo povzema situacijo. Nakazuje se velika možnost samomora enega od pilotov.

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Vsi piloti namigujejo na to moznost...

Druga verjetna razlaga bi bila da varnostna stikala niso delovala in je nekdo pomotoma z roko ruknil po stikalih in so se ta izklopla...

Kolikor vem pilot ali pa kopilot drzi rocici za moc motorja v skrajnem polozaju pri vzletu. Nato jih izpusti. Sedaj če je bil vzlet malo bolj "bumpy"
je to tudi opcija, ki je ne moreš izkljućit.

Tu še imaš Moverja... Ki kolikor vem pilotira 787


Jaz imam tezavo z tisto sekundo zato ker bi si želel da tam piše še kaj bolj podrobno koliko časa je preteklo v ms. Ker če zaokrožiš na sekundo imaš več špekulacij kot ne.

Še en slovenski članek:

Po pomoti tole izklopit je dejansko nemogoče

Uporabnik mosseero je napisal:

Tale lepo povzema situacijo. Nakazuje se velika možnost samomora enega od pilotov.

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Ta mal buče vali in vzvišeno govori, kot da pozna vse tipe letal in jih je vse letel.
Dosti dejstev kaže na to, da je bila nesreča vzrok namernega dejanja, po podrobnem pregledu zasebnih življenj pilotov bo, upajmo, jasno več. Nihče si ne želi dodatnih omejitev, ki jih kot posledico teh bizarnih dogodkov vedno fašemo vsi, povezani s to industrijo.
In ja, ponesreči se teh stikal nikakor ne da premakniti, imamo na 747 identične.
Morda je prišlo do kakšnega "kratkega stika" in napačnega signala v stikalih, preden sta ugotovila, da sta šla oba motorja v sekvenco ugašanja (stikalo ne prekine samo goriva, temveč ima še nekaj drugih pod-funkcij), na kar bi bila edina pravilna akcija premaknitev stikal na cutoff in takoj nato nazaj na run, kar resetira fadec in začne sekvenco ponovnega prižiga (takojšnji "memory item" za primer ugasnitve vseh motorjev), kar sta naredila, vendar se časovno ni izšlo.