Posts by user "BraceBrace" [Posts: 8 Total up-votes: 0 Pages: 1]

Just run a performance calculation with different flaps and compare V2 values. It\x92s not going to kill you with 2 working engines.

It's funny to watch posts like these and the "discomfort" when somebody else has to do these calculations. Dispatch can do erroneous inputs as well so we have to verify those numbers every single time. The few times I've had to ask dispatch to perform calculations, I wasn't feeling very comfortable as in my company they do not have the habit and there is a lot more chance of "garbage in, garbage out". There is always a procedure that calculations need to be done by 2 different persons, if dispatch has to do that there is no control over that procedure from my side, the guy who in the end is responsible for those numbers.

I have been using EFB all my life and can only confirm that every company has very strict procedures. And history has shown that if they are not followed, the end result is usually a tailstrike, not a stall inflight. As thrust can be increased on the spot, flaps influence (as long as not up) is highly overrated (as is in this thread) as there isn't that big of a difference between the V2 values of different flap settings.

The Air India crash is a obvious case of loss of thrust on both engines. The flight trajectory resembles a typical "too high and held off flare" that happens many times on training flights which with low time ab-initio's, that without correct re-input of thrust, leads to tailstrike. The nose up attitude, tail impact first shows engines were idle or out up to impact. Both engines to be clear, otherwise the aircraft would start to roll due to reduced rudder efficiency at low speed and higher thrust on one side. That's just pure physics, and physics can't be changed.

During a flameout it takes a while before the fan has slowed down sufficiently. As long as it rotates, thrust is generated.

With full reverse thrust you know that when de-selecting reverser from idle reverse, you have to give the engines plenty of time to slow down otherwise you would get the little "kick in the back" as during deceleration you would generate instant forward thrust when the reversers are stowed.

You are using explanations that are correct but with wrong appreciation for the values and how much thrust is available and what it is used for. Yes, the relation is not linear, far from, but the thrust required at low altitudes is for the initial climbout and acceleration, aka against gravity.

70% is not "very little", it is almost the required thrust in level flight with intermediate flaps out and gear down at those altitudes (depending on the weight). Without the gear, 60% is enough to keep level flight. If you want to descend, 55% is enough to keep speed with flaps full landing configuration and gear down on a 3\xb0 glide. So even at 55% N1, the aircraft wouldn't stall, it would gradually descend if the pitch would be correct.

It is what is between 70 and max rated that is needed for the initial climbout and that thrust is "excess" as it is there needed for the second segment in case of engine out. Considering the fact that the climb only lasted 10 seconds, 2 seconds is 20% of that time where the engines were still pushing. It is not because it is "significantly less" that it is nothing (that's why when you apply full reverse and don't let the engines slow down with idle selected, you will feel the kick forward.)

If you look at the takeoff video, you will see that the aircraft does a very rotation that some pilots prefer to avoid tailstrike: first initial rotation, constant pitch to allow the aircraft to become airborne avoiding tailstrike, second increase in pitch at which point the rate of climb quickly disappears. At that point, the "parabolic" maneuver with constant nose up is created, very typical for a loss of thrust (loss of airspeed with constant pitch).

Which begs the question why they never lowered the nose...

I think the correct Boeing reply would be: "it is not part of the certification process". So yes, loss of thrust on both engines during the takeoff phase is not really countered for in the procedures.

That does not mean that the pilots "out of habit" would have reverted to the procedure. Who would not? But in that case, the fuel control switches would be found in the RUN position post crash (if anything was left). So did they find the switches in the cutoff position, or did the action of switching got "stored" somewhere in FDM (not a specialist on these things, only to hear many times in the past that "maintenance is already aware" if we had an issue and called maintenance post flight)

I've had an all electrical black-out during single engine taxi, and I can assure you, it takes a while to go through all possible scenario's, one scenario being my FO had accidently switched off both engines. You just can't see those switches, so you have to look to the side and down to see those switches.

I believe (long time ago experience) there is an EICAS alert popping up when the fuel control switches are moved to cutoff. However, Boeing has a philosophy of "inhibits" below 400ft the aural alert indicating an EICAS has popped up is one of them. So as PF you would have to look at the EICAS during rotation, read the alert, then look down at the switches instantly.

Not sure if it's the first time. Peer support is fairly new in the world of pilots, that is true, which is why he probably picked it up. But we do need such programs to become active sooner rather than later, and we can only hope this crash isn't going to be a case study to promote such programs. Only time will tell. Some companies still struggle with the idea, in a not so long distant past, pilots from a large national carrier went straight into a fight and the reports got leaked. Many of us still wonder how the hell - after years of CRM talks - that could happen. It still is world governed by "male dynamics"... slowly changing. I would suspect Air India to be similar in dynamics.

Sure? Caution bell and light is inhibited up to 400ft RA or 20 seconds after lift-off, whichever comes first on a 777. Would expect the 787 to have the same inhibit.