dakota123 wrote:Waterbomber2 wrote:seahawk wrote:
Ni it would not be broken.
First there is nothing fundamentally wrong with the MAX. Add an AoA disagree warning and correct the MCAS software and it is just fine. Secondly any competition still lacks the economy of scales advantage and product support to compete with the 2 big players.
Mmmm what are we going to do about the airspeed disagree and loss of altitide indication?
Weren't ET asking the tower for ground speed and altitude readouts?
Stick shaker + AoA disagree + airspeed disagree + altitude disagree.
Just make it a package checklist item and call it ADIRU FAIL.
So why is the ADIRU failing so often and in the same phase of flight?
This is not a sensor problem.
ET and Lion Air would do well to keep a copy ofnthe current hardware and software as evidence before the software patch also silently overwrites any bugs.
AF447 couldn't recover from an airspeed disagree situation at cruise altitude. ADIRU failure in the take-off phase without clear indication is a death trap on its own, MCAS or no MCAS.
The procedure is to crosscheck airspeed on takeoff run, which could have shown up an issue before V1 — and maybe it did, but after V1. If in flight, crosscheck against the standby instrumentation, which has its own pitot and static system, and decide which side is giving correct info. So doesn’t make much sense that they would be asking externally. It’s a commonly trained scenario, or it should be. Will certainly be interesting if there was a valid reason as to why.
I’m not sure too many conclusions can be drawn from AF447. Certainly not the first time, nor the last, that an airspeed disagree happened in cruise, or any phase.
You make it sound easy like peeling onions.
When 2 indicators are disagreeing with 3 indicators, and the former are warning of you a stall, how do you decide which ones to follow?
It wouldn't be the first time that an idiot in MX covers up the static port of the standby instrument and forgets to remove it. That would cause the airspeed indication to be inflated, wouldn't it?
A 8000 hour pilot would probably have been through airspeed disagree training like 10 times and know that he would need to compare against the standby instruments.
A 350 hour pilot who has just been through type training and line training would also have this reviewed very recently.
And yet they asked ATC for ground speed.
I think that I know why and it's nothing less than good airmanship.
On one side you have the stick shaker activated by AOA sensor, and a low speed indication which would be sensed by a different set of sensors, ie the pitot/static probe combination, on the other side everything is looking good. But it's rather weird that two different unrelated sensors are giving incoherent information.
So which one is giving the correct information? The standby and opposite side's instruments or your instruments? Did MX cover up some static ports?
As a pilot you have to assume the worst and that's that the aircraft is stalling. You just don't ignore a stick shaker. Ignoring a stick shaker is incredibly counter-intuitive.
That's when you ask ATC for a ground speed read-out. That's just plain good sense.
I once took off with a partially clogged pitot tube on a Cessna 150.
Speed is alive, then it keeps rising, but by the time that I realised that the airspeed is stagnating and checked my throttle position, engine RPM, a quick glipse that the flaps are indeed up, the aircraft is floating off the ground.
Flew the circuit with airspeed stuck below Vstall, which despite all training is terrifying, believe me.
After landing, pissed that someone didn't put the pitot covers before leaving it parked overnight, wrote it up in the techlog and put red tape all over the control column before an idiot takes it up and kills himself.
The mechanic then approached me and asked me why I wrote it up in the techlog, now he was going to have to fill an EASA CRS, which would cost money. I told him that I'm a mechanic on commerical aircraft and that what he was suggesting was criminal. Then he asked why I didn't abort the take-off. At that point I walked away as I was about to put a hole in his face.
The B737NG doesn't have this high of an instrument failure rate.
If you look at the B737NG ADIRS, it has two ADIRU completely separated. The only thing they have in common is the TAT probe.
I don't have any B737MAX manuals, but I assume this would be the same.
So either the TAT probe made both ADIRU go nuts, or there was something else.
The assumptions that the pilots were idiots can only be made as the last solution, once all other possibilities have been ruled out.
Starting with that assumption makes us idiots.