PPRuNe Forums - 744 RTO

PPRuNe Forums (https://www.pprune.org/)

- Tech Log (https://www.pprune.org/tech-log-15/)

- - 744 RTO (https://www.pprune.org/tech-log/643613-744-rto.html)

I think it would be best to stick with the auto brakes RTO. They will maximize braking effectiveness to release just enough which the pilot would likely not be able to do.

If I remember correctly, some or maybe all Boeings inhibit anti-skid at 15 knots. If that happens on auto brakes RTO, that could create a skid at low speed. But I think going to manual braking near the end of the runway would result in a similar outcome.

Quote:

Originally Posted by 70 Mustang (Post 11161311)

Automatic Brakes
Boeing recommends that whenever runway limited, using higher than normalapproach speeds, landing on slippery runways or landing in a crosswind, the
autobrake system be used.
For normal operation of the autobrake system select a deceleration setting.
Settings include:
•
MAX: Used when minimum stopping distance is required. Deceleration
rate is less than that produced by full manual braking

I think it was already discussed somewhere recently that deceleration with landing auto brakes is different than RTO auto brakes.

Landing autobrakes(let’s assume max) will release brake pressure if the braking plus reverse thrust exceeds the selected deceleration rate.

RTO autobrakes is maximum possible braking plus whatever other slowing down capability, such as reverse, is used.

Therefore, the information you quoted, which mentions that you are choosing a fixed artificial deceleration rate versus a maximum deceleration rate, seems to not be applicable.

Please, mates.
Does anybody have the chapter of any Boeing manual that explains the messages inhibition durig takeoff phase ?

Thanks

There’s a three page table in chapter 15 of the 744 FCOM vol 2 of what’s inhibited when during the TO plus a page for landing inhibited items and another for before start and after shutdown items.