CRJ - Actual landing distances - Non-normals
I have been flying CRJ for quite some years, but it is only until a recent encounter in the sim with a new TRI the following question and confusion has popped up.
Let's say you are dealing with a system malfunction which will decrease the stopping capability of the aircraft.
In this example, let's look at HYD 2 LO PRES.
The actual landing distance now needs to be INSCREASED by a factor of 1.75 (with one thrust reverser operative).
Here the confusion starts:
In the note shown in the QRH, they don't refer to which section in the QRH to find the actual landing distance, nor does it refer to which specific table to use (Flaps 45, or Flap 20).
From experience PERF-04 covers Actual landing distnaces (ALD) for DRY, where as PERF-06 covers WET and CONTAMINATED.
In other Abnormals the QRH usually refers to ALD for FLAP 45 located in PERF-04, or PERF-06, but not in this case.
Lets now consider two different scenarios, one where the runway is DRY, and one where the runway is CONTAMINATED with Compacted Snow.
DRY:
PERF 04-5
31.000 kg gives around 948m (At 0 preassure alt)
In the notes below the table we find:
Vref - Speed at 50 ft screen height, FLAPS 45
----------------------------------------------------------------------------------------
CONTAMINATED:
PERF 06-25
31.000 kg gives 1362 m (0 pressure alt)
In the notes below we find
Distance: + 16 meters / kt above VREF FLAP 45
+ 116 meters when one thrust reverser inoperative
Now, the confusion is that the TRI is claiming that since we land at FLAP 20 with the above mentioned hydraulic malfunction, we need to add the 16 meters (Becasue the landing speed is Vref flap 45 + 12 knots), So according to him, we need to take 16meters X 12 knots = 192m, and add that to 1362 m = 1554m, and then add the factor of 1.75 according to the QRH.
Here is where our views are different.
I am arguing that we DON'T need to add these 192meters, Since the QRH is already giving us a Factor of 1.75 (With one Thrust reverser Operative).
By his logic, I asked why we shouldn't also apply the +116 meters for the One Thrust Reverser INOP according to the note in the ALD.
For that he could not give me an answer.
Is there any CRJ Guru in here who can shed some light onto this matter?
Also, if you could provide any reference to support your claim.
Thank you!