1 minute ago, transam said:

He's a pilot on YouTube, earning a few quid with his opinion.........🤔

 

I have read that the plane's co-pilot may have made a mistake with levers....

 

So, I think it's best to wait until the experts do their thing.....😉

Why was the RAT deployed? As for being a pilot on YouTube this is true but of course he is a pilot as is the bloke from the 2nd vid I linked. I'm guessing you haven't bothered to watch the vids so you could actually make an informed comment. If you had then you'd realize the co-pilot theory was considered but now with evidence of the RAT deployment this is less likely. As I stated previously the RAT deployed or was deployed for a reason.

18 minutes ago, Hummin said:

Good thing, there is 1100 of them or more and carried 875 million people the last decade. 10% of the population in the world, 270 of them have currently died, so still quite a safe plane statistically. 

 

Yeah, but how many people can you safely cram into seat 11A ?

Just now, NanLaew said:

 

Unless it was a tail strike, that funnel of dust looks like jet wash from the unpaved bit beyond the end of the runway, so the engines were thrusting away, but maybe that dust indicates that it took longer than expected to reach V2 take-off rotation speed? They took off further down the runway because lower thrust from when they started rolling? The runway is 3,500 m long.

 

The lone survivor says there was a loud bang about "30 seconds after take-off". The flight lasted less than 30 seconds, so maybe something got mangled in the translation or his interpretation of take-off is different, ie. from when the plane started rolling? That would make his "30-second bang" somewhere during the initial ascent?

 

I'm not a pilot, or an aviation expert or an investigator, but I am going with fuel contamination.

CX780 flight from Surabaya in 2010 that barely managed to land at HKG when both engine's fuel supplies got clogged up with polymer beads. These are used in the fuel pump truck filtration system to absorb any water in the fuel being loaded. The recently refurbished refuelling pipework at the origin airport was improperly flushed and had seawater in it. The polymer beads saturated the filter, that deformed under pressure and allowed the beads to be pumped to the aircraft. The plane took off normally but fuel pressure issues arose several times during the 5-hour flight but only became serious, with engine throttle and shut down issues increasing before the final approach into Hong Kong.

The Air India aircraft had flown the following sectors before the crash: Delhi-Tokyo-Delhi-Paris-Delhi-Ahmedabad. Since the domestic hop from Delhi is only about 90 minutes, maybe most of the 100 tons of avgas needed for the flight to LGW was taken on at Ahmedabad.

You can clearly see there was no tail strike. Watch the vids. There it's said the bang was the RAT being deployed.

Just now, dinsdale said:

Why was the RAT deployed? As for being a pilot on YouTube this is true but of course he is a pilot as is the bloke from the 2nd vid I linked. I'm guessing you haven't bothered to watch the vids so you could actually make an informed comment. If you had then you'd realize the co-pilot theory was considered but now with evidence of the RAT deployment this is less likely. As I stated previously the RAT deployed or was deployed for a reason.

Don't guess, I have watched vids by flyer YouTubers, they all have different theories.

But you think that you are right, which is funny when nothing has come from the experts yet, so calm down..........🙄

3 minutes ago, dinsdale said:

Why was the RAT deployed? As for being a pilot on YouTube this is true but of course he is a pilot as is the bloke from the 2nd vid I linked. I'm guessing you haven't bothered to watch the vids so you could actually make an informed comment. If you had then you'd realize the co-pilot theory was considered but now with evidence of the RAT deployment this is less likely. As I stated previously the RAT deployed or was deployed for a reason.

Can you give an evidence of the rat deployed?  Or just poor indications the rat was deployed? 
 

just the sound doesnt prove anything or the blurry pixels. The distance and acoustics in the neighborhood can have made the sound, or it is edited in postproduction for the sake of speculations or a dirt package. Conspiracy, yes, proven no, just as any speculations so far. 

1 minute ago, dinsdale said:

You can clearly see there was no tail strike. Watch the vids. There it's said the bang was the RAT being deployed.

 

Sorry, unless there's a third video that I have missed, you cannot "clearly" see anything related to V2 in the video I am referring to. There's a low building obscuring the view at the point the aircraft lifts off the runway.

 

If the experts say that a RAT makes a "bang" when they are deployed, then I will take their word for it. Maybe that's what the sole survivor heard?

 

I am not suggesting there was a tail strike, and I am not suggesting the bang was a tail strike. I am suggesting that the "dust" in the video being broadly discussed here was from the unpaved or unswept bit of apron off-end of the runway, meaning the engines were thrusting, but to me it seems pretty close to the end of the runway.

23 minutes ago, Hummin said:

Can you give an evidence of the rat deployed?  Or just poor indications the rat was deployed? 
 

just the sound doesnt prove anything or the blurry pixels. The distance and acoustics in the neighborhood can have made the sound, or it is edited in postproduction for the sake of speculations or a dirt package. Conspiracy, yes, proven no, just as any speculations so far. 

I linked 2 videos. Try watching them. Here's another 2. Sure seems to me the RAT was deployed.

 

3 hours ago, dinsdale said:

Dual engine failure? Original footage showing the ram air turbine was deployed.

 

 

Thanks for posting this.  Very interesting and learned something that I didn't know!  But yeah, the jet sounded like a prop-job when it passed the camera.  RAT?  Sounds like.

22 minutes ago, dinsdale said:

I linked 2 videos. Try watching them. Here's another 2. Sure seems to me the RAT was deployed.

 

They need more rats to hold the plane up

1 hour ago, NanLaew said:

I am going with fuel contamination

 

It's a possibility. We'd have to see the evidence.

 

It's a real possibility, but both engines' fuel lines clogegd up at the same time?

 

it's a real mystery.

 

Whoops...

 

9 minutes ago, Cameroni said:

 

It's a possibility. We'd have to see the evidence.

 

It's a real possibility, but both engines' fuel lines clogegd up at the same time?

 

it's a real mystery.

 

Fuel contamination doesn't necessarily mean clogged fuel lines. Water can be a contaminate. Not such a good thing for jet engines that's for sure. Contamination is indeed a possibility. Sure seems something took out both engines. 

I'd like to put some perspective on this, from a pilot's point of view.

Firstly, the plane lifted right at the end of the runway.  We know this because the buildings at the far end are approaching very quickly and dust was blown up by the thrust from the engines (or, additionally, from the downwash from the wings) when it rotated.  This is not normal.  When an airline pilot is planning his flight he looks at the flight conditions (weight of passengers and cargo, amount of fuel onboard, outside temperature, humidity and pressure) and instructs the flight computer on the plane how much power to use for the takeoff.  For short-haul flights it is quite normal to only use 85-95% of available power for the takeoff (no point wasting fuel and causing unnecessary stress and wear on the engines).  The main point, however, is that they will use enough power to lift off around 75% of the length of the runway.

We all know that pilots use V speeds.  V1 is the crucial 'go or no go' speed, above which you are committed to takeoff because there isn't going to be enough runway left to stop.  It is reasonable to assume no problem was known at this point otherwise they would have aborted the takeoff.

However, as stated, they used far more runway than anyone would expect.  Therefore, it is reasonable to assume that the crew knew they had an issue before they even got airborne because they wouldn't have chosen to leave it so late to rotate.

Secondly, the climb.  As we know, the highest recorded height above the ground was 653 feet, after which it steadily descended.  On initial takeoff, an airliner is typically doing 4000-5000 feet per minute in the climb.  The video shows that it limped up to 653 feet and then levelled off.  It is reasonable to assume that full power was not being delivered almost immediately after rotation, and possibly earlier.

Thirdly, airliners use flaps for takeoff and initial climb.  Not as much flap as when landing but they still need the lift augmentation to get airborne.  Whilst the video doesn't appear to show any flaps, five degrees of flap would be difficult to see clearly.  There are also leading-edge slats that extend forward; there's no way to see if these were deployed.  Given the frequently-stated fact that the plane will issue urgent warnings if takeoff power is applied without flaps it is reasonable to assume they were deployed.

Fourthly, the landing gear being down.  The crew knew they had power issues, as stated in the mayday call.  They would have known that unless they could fix it very quickly gravity would win so the best thing to do when you know you are going down is to leave the undercarriage down to absorb some of the forces when it arrives on the ground again.

Fifthly, the audio does appear to show that the RAT was deployed and working.  It sounds a bit like a NA Harvard taking off (Harvard propellor tips go supersonic on full power and make a din that can be heard miles away) or, more simply, a small two-stroke outboard motor at full chat.  Find other videos of RATs working and you'll recognise the unmistakeable sound.

Lastly, the surviving passenger said that the aircraft seemed to hang in the air for a few moments before descending.  He also stated that the noise of the engines then increased.  The 'hanging in the air' sensation would be felt if the engines weren't producing much thrust - the plane is pointing up and, without thrust, it will be slowing down rapidly and then descending.  Whether the passenger is accurately describing the engines spooling up or not is conjecture - did he mistake the noise of the RAT, perhaps?  However, even if the engines were spooling up, it may have been too late to arrest the descent and get enough speed and thrust to start climbing again.  They only reached a maximum of around 650 feet and may have needed 1000-2000 feet to convert the descent back into a climb (FWIW, I beleive the aircraft's inertia could have taken it to 650 feet after it lifted off, even if there was negligle thrust available).  If full power returned (that's a big 'if') the pilots would have been able to use it and the descent would have been arrested almost immediatly.  Full takeoff power - known as TOGA (takeoff and go-around power) - is the full 100% and watching any airliner descending to land and then deciding to go-around will show that a glide descent (the condition of the Air India plane) can be converted into a climb in 4-5 seconds.  The video appears to show a consistent descent all the way down, with the nose being raised slightly before impact to flare the aircraft, i.e. slow it down further to minimise the speed of impact, as would be expected under the circumstances.

All the above is stated objectively from the visual and audio evidence available.  Anything else is subjective, speculative or conjecture.

I, like you, await the official findings.
 

37 minutes ago, Cameroni said:

 

It's a possibility. We'd have to see the evidence.

 

It's a real possibility, but both engines' fuel lines clogegd up at the same time?

 

it's a real mystery.

 

 

Remote possibility. In the near-disaster with the CX flight I mentioned earlier, BOTH engines were affected with one stalling and the other, due to the combination of automated protocols for a single-engine landing and the same fuel contamination that stalled the other engine, stuck on 75% thrust.

The Rat is Automatically deployed when both Engines have stopped running. The rat only looks small but its sufficient to power some Avionics and a radio. The Rat sounds like a Drone so its easy to identify from a jet Engine. The Video circulated of Air India is from a mobile phone if you look close you will see a shadow on the phone screen and voices in the back ground. A video unedited is clearer and the sound if you listen closer is different and I believe the sound is a rat spinning.

12 minutes ago, IsaanT said:

I'd like to put some perspective on this, from a pilot's point of view.

Firstly, the plane lifted right at the end of the runway.  We know this because the buildings at the far end are approaching very quickly and dust was blown up by the thrust from the engines when it rotated.  This is not normal.  When an airline pilot is planning his flight he looks at the flight conditions (weight of passengers and cargo, amount of fuel onboard, outside temperature, humidity and pressure) and instructs the flight computer on the plane how much power to use for the takeoff.  For short-haul flights it is quite normal to only use 85-95% of available power for the takeoff (no point wasting fuel and causing unnecessary stress and wear on the engines).  The main point, however, is that they will use enough power to lift off around 75% of the length of the runway.

We all know that pilots use V speeds.  V1 is the crucial 'go or no go' speed, above which you are committed to takeoff because there isn't going to be enough runway left to stop.  It is reasonable to assume no problem was known at this point otherwise they would have aborted the takeoff.

However, as stated, they used far more runway than anyone would expect.  Therefore, it is reasonable to assume that the crew knew they had an issue before they even got airborne.

Secondly, the climb.  As we know, the highest recorded height above the ground was 653 feet, after which it steadily descended.  On initial takeoff, an airliner is typically doing 4000-5000 feet per minute in the climb.  The video shows that it limped up to 653 feet and then levelled off.  It is reasonable to assume that full power was not being delivered almost immediately after rotation, and possibly earlier.

Thirdly, airliners use flaps for takeoff and initial climb.  Not as much flap as when landing but they still need the lift augmentation to get airborne.  Whilst the video doesn't appear to show any flaps, five degrees of flap would be difficult to see clearly.  There are also leading-edge slats that extend forward; there's no way to see if these were deployed.  Given the frequently-stated fact that the plane will issue urgent warnings if takeoff power is applied without flaps it is reasonable to assume they were deployed.

Fourthly, the landing gear being down.  The crew knew they had power issues, as stated in the mayday call.  They would have known that unless they could fix it very quickly gravity would win so the best thing to do when you know you are going down is to leave the undercarriage down to absorb some of the forces when it arrives on the ground again.

Fifthly, the audio does appear to show that the RAT was deployed and working.  It sounds a bit like a NA Harvard taking off (Harvard propellor tips go supersonic on full power and make a din that can be heard miles away) or, more simply, a small two-stroke outboard motor at full chat.  Find other videos of RATs working and you'll recognise the unmistakeable sound.

Lastly, the surviving passenger said that the aircraft seemed to hang in the air for a few moments before descending.  He also stated that the noise of the engines then increased.  The 'hanging in the air' sensation would be felt if the engines weren't producing much thrust - the plane is pointing up and, without thrust, it will be slowing down rapidly and then descending.  Whether the passenger is accurately describing the engines spooling up or not is conjecture - did he mistake the noise of the RAT, perhaps?  However, even if the engines were spooling up, it may have been too late to arrest the descent and get enough speed and thrust to start climbing again.  They only reached a maximum of around 650 feet and may have needed 1000-2000 feet to convert the descent back into a climb.

I, like most of you here, await the official report.
 

The Pilot will have worked out the Weight of the Aircraft in his briefing and overall weight of fuel for a long flight. The Air India flight was full, all tanks were full, he would have known he will be using maximum runway possible due to the full weight of the Aircraft.

6 minutes ago, BarraMarra said:

The Rat is Automatically deployed when both Engines have stopped running. The rat only looks small but its sufficient to power some Avionics and a radio. The Rat sounds like a Drone so its easy to identify from a jet Engine. The Video circulated of Air India is from a mobile phone if you look close you will see a shadow on the phone screen and voices in the back ground. A video unedited is clearer and the sound if you listen closer is different and I believe the sound is a rat spinning.

The Pilot will have worked out the Weight of the Aircraft in his briefing and overall weight of fuel for a long flight. The Air India flight was full, all tanks were full, he would have known he will be using maximum runway possible due to the full weight of the Aircraft.

Maximum runway does not include kicking up a dust cloud at the far end.  There was so much dust he might even have been off the end of the tarmac and in the weeds.

Even fully-loaded max weight long-haul flights lift off around 75-80% down the runway.

 

30 minutes ago, IsaanT said:

However, as stated, they used far more runway than anyone would expect.  Therefore, it is reasonable to assume that the crew knew they had an issue before they even got airborne because they wouldn't have chosen to leave it so late to rotate.

 

The local media is reporting that the aircraft used the whole length of the 3,500 m runway for take off, based on "Data from a flight tracking website."

 

However, flightradar24 shows that it turned onto the runway at the last ramp from the terminal, which is only about 1,750 from the end of the runway. Surely not, since it appears that the average, fully-loaded 787 needs a minimum of 2,600 m to take off?

https://economictimes.indiatimes.com/industry/transportation/airlines-/-aviation/air-india-crash-flight-ai-171s-last-takeoff-analysed/articleshow/121811830.cms?utm_source=contentofinterest&utm_medium=text&utm_campaign=cppst

 

5 hours ago, dinsdale said:

Dual engine failure? Original footage showing the ram air turbine was deployed.

 

 

speculations and assumptions.... why not wait for the official report from official investigators

4 hours ago, Kinnock said:

I also hope the relevant authorities are making similar logical assumptions, as the report from the formal investigation could take weeks, and if there's an issues with older 787's that could cause dual engine failure, it would be good to take preventative action sooner.

 

It took two 737 Max crashes before action was taken.

The 787 was one of the safest aircraft prior to this event. There had never been any  significant events with the B787 prior to this. Start with two important factors; This was Air India. an airline with serious issues in respect to  pilot errors, maintenance and culture.  A passenger on the flight previous to this, has stated that the cabin electronics were not functioning. He posted videos of the issue.

 

I expect that the flight recorders will show a combination of deficient maintenance and perhaps ineffective pilot response. 

3 minutes ago, Mavideol said:

speculations and assumptions.... why not wait for the official report from official investigators

 

Because it is Sunday and it is raining.

 

What's your excuse for being here?

2 minutes ago, NanLaew said:

 

The local media is reporting that the aircraft used the whole length of the 3,500 m runway for take off, based on "Data from a flight tracking website."

 

However, flightradar24 shows that it turned onto the runway at the last ramp from the terminal, which is only about 1,750 from the end of the runway.

https://economictimes.indiatimes.com/industry/transportation/airlines-/-aviation/air-india-crash-flight-ai-171s-last-takeoff-analysed/articleshow/121811830.cms?utm_source=contentofinterest&utm_medium=text&utm_campaign=cppst

 

The initial report from FlightRadar24 that the aircraft joined the runway at an intersection, rather than back-tracking the runway, has been stated by FR24 to be an inaccurate interpretation of the data.

There's no way a heavily-loaded long-haul flight would not use the full runway length available.
 

5 minutes ago, NanLaew said:

 

Because it is Sunday and it is raining.

 

What's your excuse for being here?

just to correct lost souls,  people like you

If and its a big if both Engines failed on take off so will the main fuel line have a blockage ? will the fuel be contaminated ? the NTSB are already on site looking for this. One accident a few years ago was blamed on contaminated fuel when it was looked at closely the fuel stored in the Airports jet fuel storage tanks was contaminated when it was pumped out to a fuel tanker this was delivered to the Aircrafts fuel tanks. The contamination was discovered to be ice crystals blocking fuel filters and lines. They will also already be looking at Maintenance at the Airport. One thing is certain all Dreamliner's around the globe will be inspected immediately to assure passengers safety is number 1.

36 minutes ago, Mavideol said:

speculations and assumptions.... why not wait for the official report from official investigators

Speculation and assumptions? Sure seems the RAT was deployed so why was this the case?

42 minutes ago, Mavideol said:

speculations and assumptions.... why not wait for the official report from official investigators

People like talking

Or the fuel pump and it's backups failed to work, or - pilot error.  They failed to turn the pumps on, or they showed as being turned on but were not.  

Hopefully the black (orange) boxes will shed light on this.  

2 hours ago, NanLaew said:

 

Yeah, but how many people can you safely cram into seat 11A ?

Business upgrade for one leg only 114 140,- baht

1 minute ago, connda said:

Or the fuel pump and it's backups failed to work, or - pilot error.  They failed to turn the pumps on, or they showed as being turned on but were not.  

Hopefully the black (orange) boxes will shed light on this.  

How do you take off with no fuel?

5 hours ago, newbee2022 said:

Yes, therefore assumptions, unless we'll see the report by investigation.

Its quite bizarre that you question this yet believe everything you're told about Trump, covid or Ukraine without batting an eyelid 

1 hour ago, IsaanT said:

I'd like to put some perspective on this, from a pilot's point of view.

Firstly, the plane lifted right at the end of the runway.  We know this because the buildings at the far end are approaching very quickly and dust was blown up by the thrust from the engines (or, additionally, from the downwash from the wings) when it rotated.  This is not normal.  When an airline pilot is planning his flight he looks at the flight conditions (weight of passengers and cargo, amount of fuel onboard, outside temperature, humidity and pressure) and instructs the flight computer on the plane how much power to use for the takeoff.  For short-haul flights it is quite normal to only use 85-95% of available power for the takeoff (no point wasting fuel and causing unnecessary stress and wear on the engines).  The main point, however, is that they will use enough power to lift off around 75% of the length of the runway.

We all know that pilots use V speeds.  V1 is the crucial 'go or no go' speed, above which you are committed to takeoff because there isn't going to be enough runway left to stop.  It is reasonable to assume no problem was known at this point otherwise they would have aborted the takeoff.

However, as stated, they used far more runway than anyone would expect.  Therefore, it is reasonable to assume that the crew knew they had an issue before they even got airborne because they wouldn't have chosen to leave it so late to rotate.

Secondly, the climb.  As we know, the highest recorded height above the ground was 653 feet, after which it steadily descended.  On initial takeoff, an airliner is typically doing 4000-5000 feet per minute in the climb.  The video shows that it limped up to 653 feet and then levelled off.  It is reasonable to assume that full power was not being delivered almost immediately after rotation, and possibly earlier.

Thirdly, airliners use flaps for takeoff and initial climb.  Not as much flap as when landing but they still need the lift augmentation to get airborne.  Whilst the video doesn't appear to show any flaps, five degrees of flap would be difficult to see clearly.  There are also leading-edge slats that extend forward; there's no way to see if these were deployed.  Given the frequently-stated fact that the plane will issue urgent warnings if takeoff power is applied without flaps it is reasonable to assume they were deployed.

Fourthly, the landing gear being down.  The crew knew they had power issues, as stated in the mayday call.  They would have known that unless they could fix it very quickly gravity would win so the best thing to do when you know you are going down is to leave the undercarriage down to absorb some of the forces when it arrives on the ground again.

Fifthly, the audio does appear to show that the RAT was deployed and working.  It sounds a bit like a NA Harvard taking off (Harvard propellor tips go supersonic on full power and make a din that can be heard miles away) or, more simply, a small two-stroke outboard motor at full chat.  Find other videos of RATs working and you'll recognise the unmistakeable sound.

Lastly, the surviving passenger said that the aircraft seemed to hang in the air for a few moments before descending.  He also stated that the noise of the engines then increased.  The 'hanging in the air' sensation would be felt if the engines weren't producing much thrust - the plane is pointing up and, without thrust, it will be slowing down rapidly and then descending.  Whether the passenger is accurately describing the engines spooling up or not is conjecture - did he mistake the noise of the RAT, perhaps?  However, even if the engines were spooling up, it may have been too late to arrest the descent and get enough speed and thrust to start climbing again.  They only reached a maximum of around 650 feet and may have needed 1000-2000 feet to convert the descent back into a climb (FWIW, I beleive the aircraft's inertia could have taken it to 650 feet after it lifted off, even if there was negligle thrust available).  If full power returned (that's a big 'if') the pilots would have been able to use it and the descent would have been arrested almost immediatly.  Full takeoff power - known as TOGA (takeoff and go-around power) - is the full 100% and watching any airliner descending to land and then deciding to go-around will show that a glide descent (the condition of the Air India plane) can be converted into a climb in 4-5 seconds.  The video appears to show a consistent descent all the way down, with the nose being raised slightly before impact to flare the aircraft, i.e. slow it down further to minimise the speed of impact, as would be expected under the circumstances.

All the above is stated objectively from the visual and audio evidence available.  Anything else is subjective, speculative or conjecture.

I, like you, await the official findings.
 

Good summation.  Something sure happened past the PNR and probably before rotation being as you state at the very max of the runway. RAT deployed, landing gear not retracted and both engines lost thrust. IMHO there is nothing speculative about these 3 things.