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Originally Posted by revots33
I was wondering how often pilots of large jets come close to running out of runway on the landing? I've been on flights where it seemed like we were over the runway for a LONG time before the wheels touched down, and then there would be a hard braking that feels like the pilot jamming on the brakes because he was running out of room.
That's extremely rare, and it better be. I can't recall any time as an airline pilot where I came close to running out of runway. Now that's not to say that I haven't planned for the constraints of a short runway, especially if the braking action is reported as less than "Good" due to snow or sleet.
When I'm briefing an approach to a short runway, I emphasize the importance of landing as close to the target touchdown spot (1000' from the threshold) as possible. I also make sure to not carry any extra speed as this will significantly increase the distance needed for bringing the plane to a stop.
In the plane I'm currently flying (MD-88), one of the primary considerations for not using excessive runway is making sure that the spoilers deploy after the wheels touch down. This puts more weight on the main landing gear (by destroying the lift of the wings) and thus aids in effective braking.
Spoiler deployment occurs automatically as a function of "weight on wheels," and it's the non-flying pilot's duty to ensure that they've actually deployed and to call it out. If the automatic deployment doesn't work, we manually deploy the spoilers but that second or two required to see that they haven't come up, and then to pull the spoiler handle, will result in extra distance chewed up on the landing roll. In the few cases I can recall of an MD-88 going off a runway, lack of spoiler deployment has been a contributing factor.
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Also on the flip side, do pilots ever get a bad feeling that a plane isn't going to get airborne in time on takeoff?
The four things we brief as a reason for aborting a takeoff after 80 knots (and prior to V1) are "fire, failure, shear or fear." It makes for a catchy phrase and translates to: (1) engine fire, (2) engine failure, (3) windshear, and (4) judgment by the pilot that the plane either won't get airborne or will be unmanageable once it does get airborne.
The first two of these are pretty apparent. If an engine fire occurs it will be unmistakable. There will be a fire bell, a few red lights illuminating (the red Master Warning light in on each pilot's glareshield, a red FIRE light on the Overhead Annunciator Panel, and the red fire extinguisher turn-and-pull handle for the respective engine) and an aural warning "FIRE, LEFT ENGINE."
If an engine failure occurs, it will first be noticeable by the airplane yawing from the centerline due to asymmetric thrust and then soon followed by some yellow caution lights and annunciation as the generator for that engine spins down and goes offline.
Windshear identification can be trickier, depending on where in the takeoff roll it occurs. Some airplanes have windshear warning systems, but these are inhibited above 80 knots until after becoming airborne. So after 80 knots, it is up to the pilots to notice fluctuations in the airspeed indicator that indicate windshear (the worst of these would be airspeed stagnation where we continue down the runway but the airspeed stops increasing; remember: we need a certain airspeed to fly). The good news is that windshear doesn't just pop up completely unannounced. There is usually weather conducive to windshear in the vicinity that puts the pilots on their toes concerning this threat and therefore we brief it before takeoff and we're looking for these indicators.
That brings me to #4: the "fear" part of the abort briefing. This, again, is going to mainly be pilot judgment. We just know what a normally accelerating airplane feels like and typically the airspeed increases at a nice pace. If we get the "bad feeling" you mention, we can abort the takeoff just based on that. I can't remember ever doing this.
Another possible "fear" would be if for some reason we discerned that the flight controls (aileron, elevator and/or rudder) were not operating normally. This could make the plane unmanageable after becoming airborne. We do flight control checks to ensure free and proper movement of all the flight controls during the taxi check, so it shouldn't be something that comes up during the takeoff roll.
Outside of the simulator, I have never aborted a takeoff roll above 80 knots, so I've never experienced (in real life, that is) any of the "fire, failure, shear or fear" reasons for aborting a takeoff. I've had each of the first three every time I go to recurrent training.
I've aborted takeoffs during the slow speed phase (below 80 knots) probably fewer than a dozen times over my years as an airline pilot and it's usually due to an engine indication problem (e.g. all of the left engine instruments just decide to blank out after initiating the takeoff roll).