Search found 13 matches

by felipekk
Thu May 09, 2019 2:40 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 420130

Re: Boeing 737MAX Grounded Worldwide Q2 2019

I think that we'll need to wait for a full report to see what Alerts were triggered. From the traces, it appears that the L/R Airspeed Indicators differed by 10-15 KIAS and the L/R Altimeters by >500' when Flaps up was selected.. This should have triggered both Airspeed Unreliable and Altitude Disa...

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by felipekk
Wed May 08, 2019 10:08 am
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 420130

Re: Boeing 737MAX Grounded Worldwide Q2 2019

But this assertion is very obviously wrong for the MCAS that directly command the horizontal stabilizer trim actuator, one of the main control surface. But it is only a minor command, which happens only on some rather extreme parts of the flight envelope, and which can be immediately countered with...

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by felipekk
Mon May 06, 2019 7:25 am
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q2 2019
Replies: 9
Views: 5260

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q2 2019

Thanks for the calculations XRay. Now we would need to know how long the two short blips were, but it is hard to say from the graph alone. Considering we don't have this information I would consider this analysis to be inconclusive then. It could be that the two short blips were around 0.4s each, an...

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by felipekk
Sun May 05, 2019 7:55 am
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q2 2019
Replies: 9
Views: 5260

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q2 2019

Ok can we estimate how long would it take with manual electric trim to move it from 2.1 to 2.3? To see if it is consistent with their two "blips". Because it could still be that in the first few milliseconds they got the trim up to 2.3 but that it then stopped (because of aerodynamic press...

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by felipekk
Thu May 02, 2019 10:01 am
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q2 2019
Replies: 9
Views: 5260

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q2 2019

Could it be that the ET302 crew were using the trim wheels rotation as feedback to know if manual electrical trim was working or not? In this scenario would it be plausible that the two short blips of manual electrical trim nose up that we see after the ET302 crew re-enabled electric trim were long ...

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by felipekk
Wed Mar 20, 2019 5:19 pm
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q1 2019
Replies: 5479
Views: 753808

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

If it took a jump seat pilot to teach the crew how to turn off the Stab Trim, which they ALL should have known by memory, then that's almost criminal incompetence. You're jumping to conclusions. There is no evidence that the crew did not know the procedure. What is known is that they did not do it,...

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by felipekk
Tue Mar 19, 2019 3:45 pm
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q1 2019
Replies: 5479
Views: 753808

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

I have skimmed through the past 5 or so pages and don't see anything listed to date. Back in the original pages, there were claims that the flight crew reported unreliable airspeed. According to avherald.com, it is now said "there had been no indication of unreliable airspeed by the flight cre...

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by felipekk
Mon Mar 18, 2019 5:51 pm
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q1 2019
Replies: 5479
Views: 753808

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

I’d like to see a source that airspeed indications are sourced from AOA, not pitot/static system inputs. It’d be unique. GF He's not saying that they are sourced, he is saying that the AOA is used in the calculation, as explained by: Well it could be that one led to the other. Normally indicated ai...

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by felipekk
Fri Mar 15, 2019 8:51 am
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q1 2019
Replies: 5479
Views: 753808

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

What I fear is that there is unreliable airspeed from the take off roll, and they were shocked to see stick shaker on from the take off roll, and decided to shallow out the climb to "get out of it"... only to not see it not disappear.... with the increasing speed and confusion with the st...

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by felipekk
Thu Mar 14, 2019 12:46 pm
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q1 2019
Replies: 5479
Views: 753808

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Which other systems are disabled if the crew toggled the cutoff switch as per the procedure to disable MCAS? All automatic pitch trim functions stop and the pilots would have to manually trim the aircraft - something they are trained to handle. What about the Speed Trim System? Could it be that dis...

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by felipekk
Thu Mar 14, 2019 10:35 am
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q1 2019
Replies: 5479
Views: 753808

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Which other systems are disabled if the crew toggled the cutoff switch as per the procedure to disable MCAS?

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by felipekk
Wed Mar 13, 2019 2:01 pm
Forum: Civil Aviation
Topic: Ethiopian Airlines 737MAX crashes enroute to Nairobi Q1 2019
Replies: 5479
Views: 753808

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

What about the following scenario ( I have no idea if it is unrealistic, I'm an engineer, not a pilot) - Similar problems from start as the Lion Air case, pitch and power due to unreliable airspeed - Retracting flaps getting nose down from MCAS, this crew knew what to do and used the cutout switche...

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by felipekk
Tue Dec 04, 2018 4:10 pm
Forum: Civil Aviation
Topic: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang
Replies: 3187
Views: 616669

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

I understand that in the cockpit the automatic trimming would be visible through the constant spinning of the trim wheels. My question is: how/where is it shown to the pilots the current ammount of trim applied?

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