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Air India 787 crashes on take off 6

LittleInch

LittleInch

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A full 787-8 has crashed shortly after take off in ahmedabad.

Basically barely got off the ground then look like its trying to land in this video.

www.theguardian.com

Air India flight to London Gatwick crashes in Ahmedabad with more than 240 people onboard – latest updates

Plane for flight AI171 was carrying 242 people including 169 Indians and 53 Britons, says Air India
www.theguardian.com www.theguardian.com

Specualtion that they pulled flaps up instead of gear up and basically didn't have enough lift so it looks like a gentle stall right into a built up area.

Looks to be flaps up, slats/ nose flaps down and gear down which is very odd.
 
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There is more than one technique to develop full generator/alternator output at varying speeds.
And, consider an alternator or generator designed to deliver full output at the slowest speed and designed to withstand mechanical forces at the highest speed.
 
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I read that the output range is 380-800 hz on the 787.

I found this website with a detailed description of the electrical system.

kb.skyhightex.com

How to master B787 Electrical System - SkyhighTEX - Knowledge Base

It is a highly refined and automated aircraft, with automatic system configuration and load balancing. All systems of the aircraft are electrically powered;
kb.skyhightex.com kb.skyhightex.com

All power comes from 4 235vac generators. There are no separate 28vdc generators.

4 generator failure without a running APU is the trigger for automatic RAT deployment.

A single generator failure causes no change in configuration.

A 2 generator failure triggers bus reconfiguration and load shedding.

The battery backups are primarily for APU starting and wheel brakes operation. They are not primarily intended for flight controls, that is the responsibility of the RAT.

So today's question is, is a 787 allowed to take off with an out of service generator? A failure of a second generator during gear retraction may have triggered a bus reconfiguration. Can the bus reconfigure itself with such a large load present?
 
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www.scribd.com

Master Minimum Equipment List - B787 | PDF | Air Conditioning | Airplane

This document is the revision 15 of the Master Minimum Equipment List (MMEL) for the Boeing 787 aircraft, dated December 15, 2017. It was published by the U.S. Department of Transportation, Federal Aviation Administration, and provides the minimum equipment and conditions necessary to maintain...
www.scribd.com www.scribd.com

That the min equipment list for those that are interested.
 
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LittleInch said:
But why would anyone do this at take off?
Click to expand...
Guess we'll have to wait on the "manifesto" LOL

Seriously it seems impossible to move the switches to Cutoff by accident or mistake. I wonder if a practiced move could operate both with one hand simultaneously.

It appears that unless the switch panel is completely destroyed the last position of the switches will be evident, and the article says that the FDR will show that as well.
 
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There is no report yet. People familiar have simply claimed it isn't known to be mechanical because no advisories have been made.

If the intention was to take down the plane or not, why would you even try to move both levers simultaneously? They could both be switched quickly enough individually it would be hard to stop the person doing it. The only reason to switch both simultaneously is to hide the yaw.

Alistair shared the minimum equipment list and the aircraft is allowed to fly on 3 generators. Power for flight controls is primarily sourced from 3 of the 4 so depending which generator is not available there would be a significant difference in redundancy. I wish I knew the acronyms in this picture.

Screenshot_20250708-122508.png
 
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TugboatEng said:
If the intention was to take down the plane or not, why would you even try to move both levers simultaneously? They could both be switched quickly enough individually it would be hard to stop the person doing it. The only reason to switch both simultaneously is to hide the yaw.
Click to expand...

Idle speculation on my part. Less chance to get caught, interrupted. It seems the automation handles the yaw.
 
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I believe the videos showed no significant rudder deflections. The engines were at full power so any imbalance would require substantial rudder inputs, probably close to max as the speed is still low and the vertical stabilizer will have reduced control authority.
 
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LionelHutz said:
Just another speculation article.

Sure, they would be investigating to see if the switches were intentionally moved, along with investigating a long list of other things that might have caused what happened.
Click to expand...
I had put some credence on that article. On second thought, I guess you're right. I'm looking back at that article and others that reference it, and it all looks a little bit dubious. I think by this point, some agency must have some idea about what might have happened but just citing 'people familiar with the investigation' isn't very good evidence. I certainly wouldn't want to identify anything that indicates an intentional act without some confirming proof.
 
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Tru is transformer rectifier unit converting AC to DC

Fwd aft same as a boat

EP emergency power.

TU will be transformer unit.

The A might be auxillary but not sure. Could be for powering the seat screens, usb points, Led lighting in cabin etc.

I am being watched.... Apparently ATU is an auto transformer unit what ever that is or difference to a transformer unit.
 
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LionelHutz said:
Just another speculation article.

Sure, they would be investigating to see if the switches were intentionally moved, along with investigating a long list of other things that might have caused what happened.
Click to expand...

I seem to remember that it's very hard to know if a switch is moved or it's a wiring fault. It has the be crossed with the cvr hearing the movement...

They are talking about touch screens which is an idea in hell to me encouraging fingerprints on the screens. That one has issues for primary safety controls.

I suspect but don't know there may be a political reason why no info. If it was the pilots they wouldn't have a problem trashing them and Thier families. Boeing again no problem and trying to get compensation.

National carrier and those at fault still alive and a load of very rich people potentially having to pay out lots of money....
 
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It has gotten extremely difficult to extract meaningful factual accurate information from the internet, and very often impossible to validate the data and the sources. My early posts of block diagrams of the 787 electrical system clearly shows the only electrical generating elements in the 787 engines are the VFSG's, and that all other voltages and power supplies are derived from the VFSG's with the exception of RAT, main and APU batteries, or external power.

Then in a more recent post, I linked a professional looking video tutorial overview of the B787 electrical system. In that video, it is claimed there are two other independent power generating sources in the engines. One being a dedicated 28VDC PMG for flight controls, and the other being a dedicated 115VAC PMA for EEC. AI generated???

There are many hidden agendas, a lot of which are driven by governments/NGOs, in the generation of false information circulating on the internet, and deleting the valid information that does not support the controlled agenda.

If it were not for the cell phone in the wild video, we would only have the information provided by the powers in charge of investigation. Which has been Zero to this point.
 
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"Then in a more recent post, I linked a professional looking video tutorial overview of the B787 electrical system. In that video, it is claimed there are two other independent power generating sources in the engines. One being a dedicated 28VDC PMG for flight controls, and the other being a dedicated 115VAC PMA for EEC. AI generated???"

No they generate power when the N1 goes over 8% or something like that during the start cycle. If they don't come on line the fuel metering valve won't open and you will get a hung start. I can't remember if you get the ignitors firing but no fuel flow or nothing and it just sits at 25% N1 not accelerating.

If you got an electric shock off them it wouldn't kill you. The VFSG's would make you extremely crispy.
 
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