A310 doesn't follow descent profile

[ionic81]

Hi, I followed iniBuilds video tutorials on how to correctly start the descent from TOD but the airplane always arrives near the airport too high.

In the video the guy sets the target altitude and then presses PROFILE button near TOD in order to activate P.DES mode. I tried it, it doesn't work.

Another possibility, for me this is the correct one, is to set the target altitude, pull the knob in order to arm the P.DES mode, and then the airplane automatically acitvates P.DES mode when reaches TOD. The behaviour is the same as above.

Here you'll find a detailed description of what happens, I read from a real pilot that what all says about the bad VNAV performance of A310 is not real, the system is not perfect but in the real life it doesn't act like in the simulation because in this way would never get certified.

So, for me there is a bug.

In order to replicate the problem, try to do this flight (30 minutes):

Fiumicino - Pisa, Cruise altitude 12500 feets
LIRF (34L) - LIRP (ILSY04R)

Flight Plan:

NENI7M
NEMBO
T313
ELB
M729
NORNI
NORN1R

and you will arrive too high on the airport. As soon as the airplane reaches TOD the VDEV rapidly decreases (negative value) like we need to maintain altitude (???)

[DegXI_FS]

I have like a trick that help the aircraft to maintain the profile. I change my cost index to a value of 25, 40nm before my TOD and it follow perfectly fine in profile mode. Try it

[ionic81]

11 minutes ago, DegXI_FS said:

I have like a trick that help the aircraft to maintain the profile. I change my cost index to a value of 25, 40nm before my TOD and it follow perfectly fine in profile mode. Try it

Hi, I’ll try but as you wrote this is a workaround. It will be better that iniBuilds fixes this.

Have you tried my flight plan with your “trick”?

[DegXI_FS]

1 hour ago, ionic81 said:

Hi, I’ll try but as you wrote this is a workaround. It will be better that iniBuilds fixes this.

Have you tried my flight plan with your “trick”?

Yeah, a fix would be better honestly, but for the meantime this work perfect. 

Haven't tried that exact STAR but I tried other ones that looks more complex to follow and with the CI of 25 it follow all the constraints perfectly 

[ionic81]

Thanks, I’ll try but I’m waiting an official reply here and a fix

[ionic81]

I’ve used cost index of 25 (instead of 40) and in this way I landed