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Bkdoss
28th Apr 2015, 17:42
I have recently started analyzing the smoothness of my landings and the pitch at which I touchdown, primarily to cross check if the pitch values that I perceive I'm landing at is anywhere close to the actual aircraft pitch. From what I have inferred from various threads on this forum, it is the VRTA value in the S3 row of the load factor report, that gives you the g loads at the time of landing.On analyzing some of my recent landings I was surprised to note sometimes the landings which I felt were incredibly smooth and were duly appreciated by the captain, in fact carried a 'g value' several echelons above landings which I perceived to be not so on the smooth side.

Is it that the g values are prone to discrepancies to a certain extent or am I missing some part of the larger picture? And secondly there's a row of values below the s3 line which have their label as s4. What do the terms s3 and s4 refer to?

Skipping Classes
28th Apr 2015, 18:32
Unless its a hard landing, most of the time the 'g' factor is not the deceleration due to the ground contact, but the 'g' you pull during flare.

The more representative field is the vertical rate in feet/second.

Multiply by 60 to get the touch down sink rate in feet/minute.

Hope this helps :)

Flex330
28th Apr 2015, 20:39
Your FCTM helps you .....

Amadis of Gaul
29th Apr 2015, 01:15
Are you "analyzing" because you keep pranging them on or just out of curiosity?

Bkdoss
29th Apr 2015, 04:40
"The more representative field is the vertical rate in field per sec"

Alright, seems I was looking in the wrong direction all the while. Can you please throw light on which field in the load report indicates vertical sink rate?

Bkdoss
29th Apr 2015, 04:59
Amadis of Gaul

I have just got into this comfort zone where I have the confidence to pull off a landing with almost complete control, my primary aim being the centre line and the 1000 ft marker. And sometimes the smoothness of the landings and being appreciated by the skipper or the passengers give me a sense of high for the day. :p

Flex 330

I can say with reasonable confidence that the decoding of the load report is not listed in the fctm. I'd be more than happy to be proved otherwise. :)

Metro man
29th Apr 2015, 06:24
This is normally done by engineering and our company cautioned us against trying to use the FMS to determine if a landing qualified as hard or not.

Suspected hard landings to be written up in the tech log and left up to the engineers to determine.

safelife
29th Apr 2015, 08:25
My outfit just discontinued the use of those load reports do determine hard landings, as they seem so unrealiable.
(Now returned to pilot's assessment.)

whitelabel
29th Apr 2015, 10:04
Bkdoss,

Just out of curiousity. I noticed one of our trainers did it once during a line ftaining flight. Which options in the acars do you use to get the report? I dont wamt to screw around in the menu without being sure.

Thanks!

Bkdoss
29th Apr 2015, 13:41
White label,

If I remember it right, press the Mcdu menu key>AIDS>man request report (5R key I guess)> scroll down to label 15 which goes by the name load report.

stilton
30th Apr 2015, 08:37
Our 75 /67's have a printout which among other readings show vertical speed at touchdown.


Seems a more useful parameter.

Bkdoss
30th Apr 2015, 12:20
Safelife and metroman,

Even if left to the engineers to determine,there has to be some metric to quantify a landing as hard landing right? It for sure can't be left to an engineer's discretion IMHO. In my company at least the engineers depend on the load factor report, which from my evaluation is grossly unreliable.