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John K
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The vast majority of the stopping power on a landing is the wheel brakes. Reverse thrust is a much smaller component, and as it happens is generally not taken credit for in published landing distance performance data. It's just a bonus. The pilot can choose to use reverse or not, and often won't, maybe only deploying them to idle reverse to have available just in case some braking power is lost for some reason.

Aerodynamic drag is significant at first, although still way less than wheel brakes, but quickly declines as speed comes down, whereas wheel brake power (as in, what you feel as deceleration, not so much actual mathematical energy conversion) is relatively constant all the way to being stopped.

Brakes on airliners and generally split into two separate circuits on each gear, leaving half braking if a sub-system fails. If that happens, landing distance goes way up.

Then there's anti-skid (ABS in a car). Anti-skid is the only thing that allows the pilot to use maximum braking. Without anti-skid, going hard on the brakes will likely lock wheels and blow tires, because airliner brakes are like truck airbrakes, with no feedback at the pedals, just spring pressure, and you can only modulate them based on your sensation of deceleration of the plane.

So, the large majority of an airliner's stopping power is in the brake system, with the anti-skid system making it possible to exploit all of the potential braking power.

The vast majority of the stopping power on a landing is the wheel brakes. Reverse thrust is a much smaller component, and as it happens is generally not taken credit for in published landing distance performance data. It's just a bonus. The pilot can choose to use reverse or not, and often won't, maybe only deploying them to idle reverse to have available just in case some braking power is lost for some reason.

Aerodynamic drag is significant at first, although still way less than wheel brakes, but quickly declines as speed comes down, whereas wheel brake power is relatively constant all the way to being stopped.

Brakes on airliners and generally split into two separate circuits on each gear, leaving half braking if a sub-system fails. If that happens, landing distance goes way up.

Then there's anti-skid (ABS in a car). Anti-skid is the only thing that allows the pilot to use maximum braking. Without anti-skid, going hard on the brakes will likely lock wheels and blow tires, because airliner brakes are like truck airbrakes, with no feedback at the pedals, just spring pressure, and you can only modulate them based on your sensation of deceleration of the plane.

So, the large majority of an airliner's stopping power is in the brake system, with the anti-skid system making it possible to exploit all of the potential braking power.

The vast majority of the stopping power on a landing is the wheel brakes. Reverse thrust is a much smaller component, and as it happens is generally not taken credit for in published landing distance performance data. It's just a bonus. The pilot can choose to use reverse or not, and often won't, maybe only deploying them to idle reverse to have available just in case some braking power is lost for some reason.

Aerodynamic drag is significant at first, although still way less than wheel brakes, but quickly declines as speed comes down, whereas wheel brake power (as in, what you feel as deceleration, not so much actual mathematical energy conversion) is relatively constant all the way to being stopped.

Brakes on airliners and generally split into two separate circuits on each gear, leaving half braking if a sub-system fails. If that happens, landing distance goes way up.

Then there's anti-skid (ABS in a car). Anti-skid is the only thing that allows the pilot to use maximum braking. Without anti-skid, going hard on the brakes will likely lock wheels and blow tires, because airliner brakes are like truck airbrakes, with no feedback at the pedals, just spring pressure, and you can only modulate them based on your sensation of deceleration of the plane.

So, the large majority of an airliner's stopping power is in the brake system, with the anti-skid system making it possible to exploit all of the potential braking power.

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Kenn Sebesta
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The vast majority of the stopping power on a landing is the wheel brakes. Reverse thrust is a much smaller component, and as it happens is generally not taken credit for in published landing distance performance data. It's just a bonus. The pilot can choose to ruseuse reverse or not, and often won't, maybe only deploying them to idle reverse to have available just in case some braking power is lost for some reason.

Aerodynamic drag is significant at first, although still way less than wheel brakes, but quickly declines as speed comes down, whereas wheel brake power is relatively constant all the way to being stopped.

Brakes on airliners and generally split into two separate circuits on each gear, leaving half braking if a sub-system fails. If that happens, landing distance goes way up.

Then there's anti-skid (ABS in a car). Anti-skid is the only thing that allows the pilot to use maximum braking. Without anti-skid, going hard on the brakes will likely lock wheels and blow tires, because airliner brakes are like truck airbrakes, with no feedback at the pedals, just spring pressure, and you can only modulate them based on your sensation of deceleration of the plane.

So, the large majority of an airliner's stopping power is in the brake system, with the anti-skid system making it possible to exploit all of the potential braking power.

The vast majority of the stopping power on a landing is the wheel brakes. Reverse thrust is a much smaller component, and as it happens is generally not taken credit for in published landing distance performance data. It's just a bonus. The pilot can choose to ruse reverse or not, and often won't, maybe only deploying them to idle reverse to have available just in case some braking power is lost for some reason.

Aerodynamic drag is significant at first, although still way less than wheel brakes, but quickly declines as speed comes down, whereas wheel brake power is relatively constant all the way to being stopped.

Brakes on airliners and generally split into two separate circuits on each gear, leaving half braking if a sub-system fails. If that happens, landing distance goes way up.

Then there's anti-skid (ABS in a car). Anti-skid is the only thing that allows the pilot to use maximum braking. Without anti-skid, going hard on the brakes will likely lock wheels and blow tires, because airliner brakes are like truck airbrakes, with no feedback at the pedals, just spring pressure, and you can only modulate them based on your sensation of deceleration of the plane.

So, the large majority of an airliner's stopping power is in the brake system, with the anti-skid system making it possible to exploit all of the potential braking power.

The vast majority of the stopping power on a landing is the wheel brakes. Reverse thrust is a much smaller component, and as it happens is generally not taken credit for in published landing distance performance data. It's just a bonus. The pilot can choose to use reverse or not, and often won't, maybe only deploying them to idle reverse to have available just in case some braking power is lost for some reason.

Aerodynamic drag is significant at first, although still way less than wheel brakes, but quickly declines as speed comes down, whereas wheel brake power is relatively constant all the way to being stopped.

Brakes on airliners and generally split into two separate circuits on each gear, leaving half braking if a sub-system fails. If that happens, landing distance goes way up.

Then there's anti-skid (ABS in a car). Anti-skid is the only thing that allows the pilot to use maximum braking. Without anti-skid, going hard on the brakes will likely lock wheels and blow tires, because airliner brakes are like truck airbrakes, with no feedback at the pedals, just spring pressure, and you can only modulate them based on your sensation of deceleration of the plane.

So, the large majority of an airliner's stopping power is in the brake system, with the anti-skid system making it possible to exploit all of the potential braking power.

Rewritten to accommodate revised question
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John K
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Well, I used to fly CRJ200sThe vast majority of the stopping power on a landing is the wheel brakes. Reverse thrust is a much smaller component, and as it hashappens is generally not taken credit for in published landing distance performance data. It's just a very soft and compliant trailing link gearbonus. Every now and then, I happenedThe pilot can choose to get the pitch teasing through the touchdown just rightruse reverse or not, and the ground contact was so gentle that theoften won't, maybe only sensation of a landing was the wheel spin vibrations/noise startingdeploying them to idle reverse to have available just in case some braking power is lost for some reason.

When that happened, there was no discernable deceleration at wheel contact from the spinup. So while thereAerodynamic drag is probably a measurable effect if you had accelerometer data measuring longitudinal Gsignificant at mainfirst, although still way less than wheel contactbrakes, it's not enoughbut quickly declines as speed comes down, whereas wheel brake power is relatively constant all the way to feel through your buttbeing stopped.

Brakes on airliners and therefore not really significant in terms ofgenerally split into two separate circuits on each gear, leaving half braking if a sub-system fails. If that happens, landing distance goes way up. You get more detectable deceleration from spoilers

Then there's anti-skid (ABS in a car). Anti-skid is the only thing that allows the pilot to use maximum braking. Without anti-skid, going hard on the brakes will likely lock wheels and full flapsblow tires, because airliner brakes are like truck airbrakes, with no feedback at the pedals, just spring pressure, and when you getcan only modulate them based on your sensation of deceleration of the brakesplane.

So, wellthe large majority of an airliner's stopping power is in the brake system, you knowwith the anti-skid system making it possible to exploit all of the potential braking power.

Well, I used to fly CRJ200s, and it has a very soft and compliant trailing link gear. Every now and then, I happened to get the pitch teasing through the touchdown just right, and the ground contact was so gentle that the only sensation of a landing was the wheel spin vibrations/noise starting.

When that happened, there was no discernable deceleration at wheel contact from the spinup. So while there is probably a measurable effect if you had accelerometer data measuring longitudinal G at main wheel contact, it's not enough to feel through your butt and therefore not really significant in terms of landing distance. You get more detectable deceleration from spoilers and full flaps, and when you get on the brakes, well, you know it.

The vast majority of the stopping power on a landing is the wheel brakes. Reverse thrust is a much smaller component, and as it happens is generally not taken credit for in published landing distance performance data. It's just a bonus. The pilot can choose to ruse reverse or not, and often won't, maybe only deploying them to idle reverse to have available just in case some braking power is lost for some reason.

Aerodynamic drag is significant at first, although still way less than wheel brakes, but quickly declines as speed comes down, whereas wheel brake power is relatively constant all the way to being stopped.

Brakes on airliners and generally split into two separate circuits on each gear, leaving half braking if a sub-system fails. If that happens, landing distance goes way up.

Then there's anti-skid (ABS in a car). Anti-skid is the only thing that allows the pilot to use maximum braking. Without anti-skid, going hard on the brakes will likely lock wheels and blow tires, because airliner brakes are like truck airbrakes, with no feedback at the pedals, just spring pressure, and you can only modulate them based on your sensation of deceleration of the plane.

So, the large majority of an airliner's stopping power is in the brake system, with the anti-skid system making it possible to exploit all of the potential braking power.

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John K
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