(FSX 1.503)

Aircraft vertical speed far exceeds -1250fpm during a cruise descent.

Manual:
(Part II, pg. 443/444)
CRUISE DESCENT
A VNAV cruise descent is commanded at the current cruise speed and approximately 1250
feet per minute rate of descent.
The autothrottles adjust thrust to maintain the target descent rate; pitch maintains the commanded speed.
Thrust levers can be manually positioned to adjust the descent rate.
-----

Observation:

The aircraft descends at 3000fpm during a CRZ DES of 2000ft between FL360 and FL340, 94nm before the original T/D.
This greatly exceeds the quoted 1250fpm approximate descent rate.

Off-Topic replies have been moved to this Topic.

Speed intervene will set VNAV PATH into VNAV SPD even when in "ON APPROACH" MODE.
The description is on Manual part II page 349 "ON APPROACH" MODE
The condition I have is:
Approaching RJBB RWY24R, with RNAV24R(trans MATAH) programed into box.
LNAV and VNAV PATH Passsing MAYAH, try to open spped window to slow aircraft down for flaps, but when speed intervene pressed, the VNAV PATH change to VNAV SPD.
Close speed window, VNAVPATH gain back.
Tried again after BB451, again it changed into VNAV SPD.
Even after FAF, I still can't get VNAV PATH in, so I have to make an V/S approach.

AIIR#6

Angel of Attack wrote on Jul 26^th, 2020 at 2:01am:


Here is the save flight for that condition, I tried it again, same behavoir
The procedure I use was in real plane's FCOM-NP-Landing Procedure - Instrument Approach Using VNAV, altough it's not in CS's manual 3, The related system behavoir are all in CS manual 2, so no excuse here
In the save I just pass MAYAH (IAF for the approach), heading BB450, as there is a 185kts speed restrection, I need to lower the flaps, I tried to Open the IAS window for manual speed match as 757's VNAV, unlike 737's one, would not do if for me (that's well simed then ).
I also noticed 2 more issue with in the same save, but I'll report them separately as required

Angel of Attack wrote on Aug 3^rd, 2020 at 2:00pm:


2.When crossing a waypoint, the VNAV's path will "jerk around" for a bit, in this save most noticeably after MAYAH and BEIGE (but happens most of time even at high altitude). the path will likely set low (more than 400feet- out of scale) afterwise and VNAV will try to dive to that path with high descent rate.

OM457 wrote on Aug 25^th, 2020 at 11:10am:

So apparently this happens when you insert winds into legs manually. (since you can't uplink winds from ASP4 or anything)

[quote author=atav757 link=1576518392/42#42 date=1599656718]I assume CS is working on an update to get all the 767 fixes to this plane? Hope it comes out soon I’ve been waiting patiently!

Me too