Originally Posted by
hawk_eye
So from the research I had done, I was aware that the deceleration rate of AB 3 was in the order of 7 f/s and AB Max was in the order of 14 f/s. The question I posed was to find out whether an operator could request those deceleration rates to be altered - I believe an AB 3 decel of 9-10 f/s and AB 2 decel of 6-7 f/s would be far more suited to my company’s operations.
I’m interested in one posters comments suggesting that changing the deceleration rates would require a heap of flight testing from Boeing. This raises another question I don’t know the answer to, as I would have thought that the landing distances in the QRH would be derived mathematically (but obviously based on a level of flight testing during certification). Am I incorrect in that assumption?
1) There is no option to alter the rates set by the manufacturer. There IS an option for ordering the SFP variant, which enables less LDR effectively. Hopefully, your company already has the latest Boeing Performance Improvement Packages installed, which helps a little bit as well, other options are available, fleet weight reductions for one...
2) QRH distances are mathematically derived, but mathematically derived from flight test data in the first place. So new flight tests would be required to validate any new settings, from which then new QRH distances can be calculated...