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Old 17th Nov 2018, 09:10
  #56 (permalink)  
EIFFS
 
Join Date: Aug 2017
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Originally Posted by ManaAdaSystem


NG -800 has a bad rep when it comes to landing mishaps. I really hope your predicitons about the Max does not come through.
i


There is more risidual thrust and Vref is higher with a MLM of 69308, then you have another “sub system” new to the max called the LAM to ensure adequate nose gear clearance ( the NLG is 20cm longer than the NG) on landing.

The Landing​ Attitude Modifier (LAM) system performs two​ functions. The first​ ​
LAM function applies​ when the flaps are in​ the 30 or 40 position. To maintain ​
acceptable nose landing gear contact margin, LAM symmetrically deploys flight ​
spoilers on approach to reduce lift and force the airplane to use a higher angle of ​
attack. The amount of spoiler deflection depends on the approach speed. ​
Deflection begins at approximately 10​ knots above VREF.​
The second LAM function applies​ when flaps are positions 15 through​ 30​ and​ the ​
thrust levers are near idle. This function also symmetrically​ deploys flight ​
spoilers, in order to generate additional drag

The max Vref increment on the MAX is now 15 knots down from 20 on the NG ( because we fly both we have 15 max across both fleets)

Provided you follow the FCTM ie reduce thrust to idle by touch down and touch down in the correct zone ( many don’t ) and you’ve correctly completed a landing distance calculation ( again many don’t) the NG SFP & 737-800 (MAX) model have excellent stopping capability.

As you say there have been a few incidents with the NG, the risk is higher with the MAX IMHO
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