There's also a very big difference between "Engine failure: something has damaged or jammed enough components that the turbines are no longer spinning fast enough to produce thrust or drive the generators" and "Engine failure: the engine is no longer attached to the aircraft, which is why it is no longer producing thrust". However, both things are reported in the cockpit as ENG FAIL.
(Un)fortunately, cockpit warnings prioritise the what (so to speak) and not the how or why. On one hand, this makes decision-making a lot simpler for the crew, but on the other...well, in rare cases the lack of insight can exacerbate a disaster. Depending on when exactly the engine gave out, this poor crew might have been doomed either way, but they might have been able to minimise collateral damage if they knew just how badly crippled the aircraft was. And there was a very similar accident to this one (actually involving the predecessor of the MD-11, the DC-10), American Airlines 191 - one of the engines detached from the aircraft, damaging the leading edge of its wing in the process, causing that wing to stall when the crew slowed down below the stall speed of the damaged wing in a bid to climb. If they could have somehow known about the damage, the accident might have been avoided entirely as the crew might have known to keep their speed up.
In emergencies, information overload tends to make things worse, not better.
And now we have technology that allows for cameras everywhere to give a better situational awareness across all critical aircraft surfaces and systems.
It is going to take a little bit of adjusting to, but it will help improve safety in a tremendous way.
And how would the cameras even work? Are the pilots supposed to switch between multiple camera feeds, or do we install dozens of screens? And then what, they see lots of black smoke on one camera, does that really tell them that much more than the ENG FIRE alert blaring in the background?
Maybe this could help during stable flight, but in this situation, when the pilots were likely already overloaded and probably had only a few seconds to escape this situation - if it was possible at all - I can't imagine it being helpful.
Now... not sure how much that is helpful in this kind of emergency, they really didn't have time to do much.
What is the difference?
Edit: and damage to other engines, possibly engine #2 in the tail ingesting debris in this instance.
Helpful in what way? What are the pilots going to do with the information?
If we don't try to see how it goes, we won't know if it is a good idea or not.
It'd take lots of testing and engineering. But especially in cases where you have multiple warnings going off I imagine that a quick view at an exterior camera can often give you a clearer/faster indication of the situation
the problem might be getting trained and experienced pilots to adjust to it since they are already in a certain flow of habits and skills to apply in their job, but new pilots surely could learn it as they aren't so set on their ways yet and have the opportunity to build this new data into their skillset / habits.
Wanting to be in the air vs wanting to over-run the end of the runway.
> see UA1175
I'm familiar with the case you are mentioning. I'm also aware that they sent a jump seater to look at the engine. But did seeing the engine provide them with any actionable information? Did they fly the airplane differently than if they would have just seen the indications available in the cockpit?
and
"I can't walk because I have no legs"
People have an upper limit on their capacity to take in information, and that limit goes down when they are moving quickly to solve problems. Throwing more information at them in those moments increases the risk that they will take in the wrong information, disregard more important information, and make really bad decisions.
So no, it's not cut and dried like you're thinking.
This is consuming all mental processing, there are no spare cycles.
This wasn’t a salvageable situation by having more information after the engine separated. If a sensor could have provided a warning of engine failure well before V1, that would be helpful.
I expect the questions will focus on what information existed that should have resulted in aborting the takeoff. Not what information was needed to continue.
Cut fuel & hydraulic lines near that engine (that affect the other engines/ apus) (or less likely structural or aerodynamic problems) is what's going to shift this from "engine failure" recoverable problem to a global nonrecoverable one.
Stupid car analogy: airbags help in most cases, but not all. Are they useless?
Regarding UA1175, they had someone extra, but not all flights happen to have someone extra in the cockpit.
Excellent. So in what cases does seeing the engine visually do help? So far we discussed UPS2976 and UA1175 where the presence or absence of the camera didn't change the outcome.
> Regarding UA1175, they had someone extra, but not all flights happen to have someone extra in the cockpit.
You are dancing around my question. What does the pilot do differently based on what they see? If you can't articulate a clear "pilot sees X they do Y, pilot sees Z they do Q" flow then what is the video good for?
in a sibling thread you say "There are countless situations where it can be helpful." But you haven't named even one of those countless situations yet.
In other situations: - are the wheels out when the sensors say they are not - have a way to visually inspect critical parts of the plane while in flight (so you don't have to do a flyover and the tower to look with binoculars at the airplane)
This is what comes to mind now.
Happy? Or am I still dancing?
I think that statement needs the support of actual evidence. Air incident investigation agencies make detailed reports of the causes of crashes, with specific, targeted recommendations to help ensure that similar incidents don't recur.
If we haven't seen recommendations for cameras like that, then I think it's reasonable to assume that the actual experts here have determined that cameras would not be helpful.
To be fair, the presence of a camera might have changed the outcome of UPS2976. Depending on when the fire developed fully, rejecting the takeoff based on the sheer size of the fireball on the wing might have led to fewer casualties on the ground. This is of course under the assumption of a world where a camera feed is a normal part of the flight deck instruments and there is a standard for the pilot monitoring to make judgments based on it.
The engine coming completely off tore through hydraulic lines, which were need to keep the slats extended. Airflow forced the slats to retract.
Here's what then happened:
> As the aircraft had reached V1, the crew was committed to takeoff, so they followed standard procedures for an engine-out situation. This procedure is to climb at the takeoff safety airspeed (V2) and attitude (angle), as directed by the flight director. The partial electrical power failure, produced by the separation of the left engine, meant that neither the stall warning nor the slat retraction indicator was operative. Therefore, the crew did not know that the slats on the left wing were retracting. This retraction significantly raised the stall speed of the left wing. Thus, flying at the takeoff safety airspeed caused the left wing to stall while the right wing was still producing lift, so the aircraft banked sharply and uncontrollably to the left. Simulator recreations after the accident determined that "had the pilot maintained excess airspeed the accident may not have occurred.
It is not reasonable to assume anything.
Air crash investigators are not the experts on airplanes design.