Air India 787 crashes on take off 2

[LittleInch]

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.

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

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.

 

[Alistair_Heaton]

I have never seen a perm mag generator for powering the fadec depicted in any aircraft electrical block diagrams.

 

[TugboatEng]

On our diesel engines our alternators (permanent magnet generators or whatever) were found to not be very reliable so many of our vessels run battery chargers off the AC electrical system. That was fine in the 1990's when the battery chargers were the mag-amp or transformer based chargers. However, the solid state chargers have become popular and they are not reliable. I say charger but these are really power supplies that use batteries as filters. In my fleet I replace failed solid state chargers in critical applications with mag amp units from a specific vendor.

Another question, is breaker trip sequencing a part of commercial aircraft certification? It's starting to show up in a narrow portion of marine side.

 

[Alistair_Heaton]

Yes but it's airframe certification, not engine.

This is the issue with the MAX they grandfathered it when it was none compliant. But the local Boeing certifiers put it through.

 

[LittleInch]

The other idea skulking around is some fault or override on the TCMA system designed to cut engine power when on the ground and engines at a different power level to where the throttle lever were.

Now it take a whole lot of holes to line up in the Swiss cheese, but as we've seen before, this is possible once in 15 years.

The shutdown being triggered somehow by Gear up is part of this hypothesis.

The silence from the investigation is unnerving.

 

[Alistair_Heaton]

That sounds like the issue for the shut down on landing of the a220 after pilot over riding the automatics and causing confusion.

It's maybe the reason why airbus opted for an in the gate and make it very special the pilots ever touch the power levers.

Airbus had issues at the beginning with the logic. There was some suspect reports on various events in hindsight to stop all fleets being grounded. They got away with it.

 

[LittleInch]

They appear to have been able to download the FDR and CVR from the crashed units in Delhi on Wed 25th June.

Hopefully they start giving some decent answers soon.

 

[Garbage1]

As the brain behind the engines, the FADEC monitors, protects and controls the aircraft propulsion system in real time. The FADEC 3 is on board many commercial aircraft such as the Airbus A318, A319, A320, A321 and A380, Boeing 737NG, 747-800, 767, 777 and 787 Dreamliner, as well as on military platforms such as the Airbus A400M.

"Modes" in FADEC reminds me of "Mission Profiles" in Phased-Array Radars. If you did not boot system in correct 'Mission Profile' the radar could not deal with incoming threat. Basically 'Mission Profile' means you need to know what threat you are trying to address, before you boot the radar, to launch the correct software. This sounds like FADEC modes, and if in incorrect mode or programmed-in incorrect information, then you end up with FADEC responding incorrectly in a very critical moment.

FADEC aka 'micro-manager'

FADEC 3 - 3rd generation Full Authority Digital Engine Control

The FADEC 3 engine control unit provides aircraft electronic engine protection and reduces the pilot's workload. It offers lower costs of ownership and facilitates maintenance management.

www.safran-group.com