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latam accident lima

Old 11-18-2022, 02:03 PM
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Old 11-18-2022, 02:06 PM
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Is it me or does it look like the emergency vics were on the runway and the jet took out at least 2 of them...
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Old 11-18-2022, 02:12 PM
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Originally Posted by Beech Dude View Post
Is it me or does it look like the emergency vics were on the runway and the jet took out at least 2 of them...
It took one truck, killed 2 firefighters.
This is a (tragic one) that I had not seen before...
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Old 11-18-2022, 06:49 PM
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How could the vehicles not see the jet coming down the runway at them? And the pilots should have been able to see the vehicles.
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Old 11-18-2022, 07:00 PM
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Tragedy..same day blame. Some things never change.
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Old 11-18-2022, 08:38 PM
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Pax photo showing the #2 engine gone and the leading edge on fire.
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Old 11-20-2022, 04:50 AM
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Originally Posted by AirBear View Post
How could the vehicles not see the jet coming down the runway at them? And the pilots should have been able to see the vehicles.
Being able to see something headed your way, or something in the way, does not equate to being able to get out of the way, or to avoid either one.
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Old 11-20-2022, 04:56 AM
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Makes you think. You’re below V1, you see something you’ll hit whether you reject or continue. How fast would you need to be going to think, “emergency thrust, flaps 15” maybe could pull it off the ground and try to clear the vehicles?
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Old 11-20-2022, 07:18 AM
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How could you know that you'll hit the object if you continue and that you'll hit it if you stop?

Numerous video footages from various angles and still photographs are available for this mishap, including video from behind the trucks as they moved toward the runway. The collision appears to have occurred at the intersection of Bravo and 16, with the Airbus departing runway 16. That would put it a little under 4,000' into the takeoff roll. The aircraft does not appear to have had much reaction time, and the intruding aircraft entered the runway without authorization, reportedly enroute to a call for another aircraft.

The only case I can think of in which one mashes the power to max blast and rotates regardless, might be a windshear situation in which one rotates when out of runway and unable to stop...but that counsel generally points to "no later than 2,000 before the end", implying one has had as much runway as possible to get off the ground, and has encountered unexpected windshear.

A low-speed rotation below V1 does not mean the aircraft will fly, and will require a higher than normal pitch attitude, with an attendant possibility of a tail strike.

The videos do not make clear how much, if any, opportunity the pilot had to take any kind of evasive action, or what action was taken. The encounter was reportedly below V1, at around 130 knots.
"Emergency" thrust for most modern aircraft is a limited value of maximum thrust; electronic engine controls, digital engine controls, etc, limit thrust, so the emergency availability that might have been there with older aircraft is not necessarily available; V1 will have been calculated, among other things as a value above Mmcg; additional thrust will change that value. The rate of acceleration at the time such a decision is made depends on whether it was a reduced power takeoff to begin with, and by how much the reduction was made; the reduction is made based on available runway, not a suddenly shortened runway. This means that with reduced thrust, the aircraft will be slower at a given point on the runway, than it would be had the aircraft taken off with max thrust. With that in mind, the addition of max thrust at that point will have less effect than were the aircraft at a higher speed (eg, began the takeoff at max thrust); the difference may have a significant impact on whether or not the aircraft could get airborne with additional thrust. Likewise, how do you know what you'll get by adding flaps?

At what point will the crew have trained for such a senario? Inventing a scenario during the takeoff roll, particularly with an impending emergency, my further complicate the matter beyond salvation. At that point in the takeoff roll:
How do you know adding power will enable rotation and climb prior to impact?
How do you know that rejecting the takeoff will fail to avoid impact?
Adding flaps will alter the outcome, and by how much?
What effect will changing flap configuration on the runway have on a subsequent reject or braking action?

If you are below V1 and reject, at a minimum, should impact occur, it will be at a lower speed than if the takeoff continued, to impact. The energy at impact will be reduced by slowing down. Adding power and accelerating in the hopes of making it may significantly increase the damage at impact.

I think it would be very hard to definitively conclude, at the point one becomes aware of an intruding vehicle or aircraft, that:
One will impact the vehicle if a rejected takeoff is executed, AND
One will impact the vehicle if a continued takeoff is made.

Crews train ad nauseum to reject below decision speed, continue above it, with some conditionality (eg, V1 called 5 knots early, etc). Rethinking that policy on fly in a high speed situation may not be the right choice.

I have had two occasions, neither in a large aircraft, when some version of that scenario played out. One was a remote airstrip at night, when a bull entered the runway; I was in a light twin and did rotate and pick the airplane high enough to get past the bull, rather than trying to stop. I did apply flap at the same time and I did settle back down past the bull and continue. Based on what I experienced with proximity to the bull, I believe this was the only choice, and that had I attempted to stop, a collsion would certainly have occurred. I don't believe that very unusual situation would have been possible in a large aircraft.

The second occasion was in a light twin turboprop at a location where takeoffs and landings were being conducted in both directions on a single runway. a small experimental entered the runway at the opposite end. It was quite low, and had a checkerboard paint job which served to break up the outline and make it very difficult to spot. By the time I did see the aircraft, which was taking off toward us, I had no way of determining where on the runway I might stop in relation to the other aircraft. The distance between us was decreasing and our speed increasing. I was at max takeoff weight in a draggy, ratty turboprop, and I did not know the other aircraft's capabities. We did not have radio contact. The runway had hard packed flat ground on either side, with obstacles beyond that to my right and a clear area to my left. I angled to the side of the runway with maximum thrust and continued the roll off the pavement and rotated. In hindsight, I believe that had I attempted to stop on the decreasing runway between us, there's a high probability we'd have impacted, or at least, the chances would have been high. Had this event occurred in a large airplane, the evasive action taken would not have been possible.

In the case of a single fire truck in visual conditions, one would hope that with two pilots on board, a truck with flashing lights near or entering the runway might be observable, and merit some kind of action. Just how much time and at what speed the crew became away isn't clear, but it's entirely possible given the emergency vehicles racing toward the runway, and the unauthorized incursion, that the crew had little more time than necessary for an expletive before doing something. In such a case, adding thrust takes time to gain an engine response, as does adding flaps to achieve the flap setting...and then with no way of calculating the performance.

Certainly in such an unusual, unplanned situation it's very much a judgement call, and in this case we have insufficient information to do more than talk theoreticals, rather than the event itself. We just don't know. So far as the theoretical regarding rejecting vs. continuing (vs. the possibility of taking some kind of evasive action), it's very hard to be too specific without knowing what's seen out the window, and what distances, speeds, and possibilities exist. We do know that we train to reject below V1, and we do know that our performance on a rejected takeoff is calculated on a reject at V1. Factor in reaction time, startle factor, a moving target and the difficulty in taking evasive action for a target that may continue moving, or that might stop (eg, sees the aircraft taking off and brakes), it would be difficult to impossible to make a definitive reply to your idea, here. Maybe powering up would make it, maybe it would make it worse, and then again, maybe the ability to stop exists. Devil and details, and all. Most of the time, our best course of action will be to follow the training we receive, which revolves around rejecting below V1, and continuing above it.
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Old 11-20-2022, 11:26 AM
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Early rotation and striking the vehicle with the gear or tail section would have been catastrophic.
Despite the deaths on the firetruck this was the best possible outcome.

For the plane and pax.
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