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Autorouter - VFR or IFR

Achimha, quick question trying to know more how it works. I planned for LKKU-LZKZ with default build-in model PA28. 10 different options were presented to me with various combination – from complete IFR to complete VFR, 172M is generating the same number of option.. That´s fine and what I did expect. When I do the same search with SR20 I am offered only “IFR SID into VFR” and two VFR options, no full IFR option there. M20K is generating only 6 – but this time full IFR included. Looks there is something in the performance table preventing SR20 IFR arrival to LZKZ. I changed maximum descent rate from 1 000 into 2 000 fpm dive but this did not help. M20K has 1 000 fpm and allows me to get into LZKZ.
When flown last month vectors to ILS 01 required some faster descent but STAR will get me there comfortable and I believe descent performance should not limit the ability to fly IFR. Can you have a look at that sometime ? not a critical item definitely…

LKKU, LKTB

@Michal thanks for bringing this to our (my) attention.

I changed maximum descent rate from 1 000 into 2 000 fpm dive

Unfortunately that doesn’t always help anymore. The problem is Eurocontrol has some pretty bad performance model especially for GA aircraft. We used to override the worst of it by supplying our own 4D profiles calculated with the user’s performance data. Unfortunately, with their last software release, they have tightened what we can do to override this. For example, their model thinks the SR20 will need ~65NM to descend from F110 to airport altitude.

So the router first came up with:
HLV1G HLV P27 PPD R232 KSC MARKA7A on F110.

Then the Eurocontrol Profiler didn’t like it and issued a PROF50 error, thinking you would be descending too early. Our software then didn’t correctly process that PROF error, got confused and abandoned the I plan.

I changed it to come up with: HLV1G HLV P27 PPD R232 MARKA MARKA7A. This is exactly the same routing in all respects, but apparently more acceptable to Eurocontrol.

The change is not yet on the server, that will take some more time.

LSZK, Switzerland

ok, thanks

LKKU, LKTB
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