Recently we have seen a lot of codes used to unlock our products being offered for discounted prices. Almost all of them are bought using stolen credit cards. These codes will all be blocked by our systems and you will have to try to get your money back from the seller, we are unable to assist in these matters. Do be very careful when you see a deal that is almost too good to be true, it probably is too good to be true.

Jump to content
metalmike

What's up with the cruise altitudes/step climbs?

Recommended Posts

Take for example this simple route from Seattle to Juneau with the B732: YYJ J502 SSR

 

PFPX spits out: SEA DCT YYJ/N0430F280 J502 ARRUE/N0431F280 J502
           ROYST/N0432F280 J502 YZT/N0433F280 J502 PRYCE/N0433F280 J502
           DUGGS/N0433F280 J502 HANRY/N0434F280 J502 ANN/N0437F260 J502 SSR

 

In past versions of PFPX if I had step climbs they were few and made sense performance-wise. I could understand altitudes like  this (maybe not this extreme) in Europe where there are a lot more restrictions but I'm at a loss here. I could of course do the entire route without step climbs, but that doesn't make sense economically. 

 

OKAuh4GBjL.png

Share this post


Link to post

Using the MAX payload with the supplied B737-200ADV profile and online weather:

 

(FPL-B732ADV-IN
-B732/M-SDFHYZ/S
-KSEA1750
-N0425F320 DCT SEA DCT YYJ J502 SSR DCT
-PAJN0224 PAGS
-DOF/190217 REG/B732ADV
 EET/CZVR0014 PAZA0134 RVR/550 PER/C
-E/0328)

 

There are 80kt + winds from the North.

 

Using a max loaded 738 FL360 is returned.

Share this post


Link to post

My 732 is not max payload (and gave me a lower crz than you), and even still, why the constant climbs and descents? Just to chase less headwind?

Share this post


Link to post

Supplied B732 profile and PFPX weather ?

 

Here is the planning screen returning FL320:

 

capture_002_17022019_175656.thumb.jpg.5a06fb39993600479b5c7ffa098c59cd.jpg

Share this post


Link to post

I can't think of what else would cause my issue, other than maybe I'm using US FLAG rules (Alaska is flag ops, even though it's technically in the US, same thing applies to Hawaii for example). Though I get this kind of result on almost any flight I try to dispatch with step climbs.

 

Edit. also to clarify, while I am using PFPX online weather, my fuel profile is slightly modified - cruise bias is about -26% (which I imagine would make me carry less fuel and be lighter - get higher). My optimum altitude is decreased by -2000 ft - I know it seems like some weird modifications but I've found this to match the FlyJSim 732 pretty well. Even with all that though, while I'd understand slightly lower altitudes vs the default profile, what primarily annoys me is the constant climb and descent.

Share this post


Link to post

I got rid of my optimum altitude adjustment, and that seems to compute a more straightforward cruise profile.

Share this post


Link to post

I'm also having problems with the default 744 RB211 (and others) profile getting a normal performance-based step climb with no optimisations.  Altitude selection is definitlely weird compared to 1.28.8 which I was using before.  I more often than not have to force step climbs by looking at an optimum altitude vs. weight table.

Share this post


Link to post
4 minutes ago, DemonTraitor said:

Same problem here.....

 

image.thumb.png.617861210ca4f23db95b2237220f57d3.png

 

Full OFP ?

Share this post


Link to post

Guys how can anyone give an answer with NO useful information.

 

NO route in text format, NO OFP will lead to no answer from me.

Share this post


Link to post

(FPL-JAI003-IS
-B738/M-SDE1FGHIJ1RWXYZ/LB1
-EGBB1005
-N0372F220 LUVUM DCT TNT N57 POL/N0386F260 UN601 RIBEL
-EGPF0044 EGNV
-PBN/A1B1C1D1L1O1S1 NAV/RNVD1E2A1 DOF/190602 REG/VTJBQ
 EET/EGTT0017 RVR/200 PER/C 
-E/0140)

Share this post


Link to post
14 minutes ago, Teddy said:

(FPL-JAI003-IS
-B738/M-SDE1FGHIJ1RWXYZ/LB1
-EGBB1005
-N0372F220 LUVUM DCT TNT N57 POL/N0386F260 UN601 RIBEL
-EGPF0044 EGNV
-PBN/A1B1C1D1L1O1S1 NAV/RNVD1E2A1 DOF/190602 REG/VTJBQ
 EET/EGTT0017 RVR/200 PER/C 
-E/0140)

 

The route is level capped to FL285 by RAD, really not much wrong with that, increasing the final cruise to 280 results in greater fuel burn.

Share this post


Link to post

Hi Stephan

 

Thanks for trying to help me out.  The issue is not so much about the altitude than the problem with suggesting FL220 in the beginning then a descent followed by a descent and then a climb again.

 

That's what I am not able to figure out.

 

Regards

Ted

Share this post


Link to post

I don't see that here, are you using an addon performance file ? tried a profile other than LRC ?

 

There is an issue with short trip levels, selecting INIT ALT = MAX and no STEP can overcome unnecessary low levels but that shouldn't the problem here.

 

 

Share this post


Link to post


1 hour ago, srcooke said:

 

There is an issue with short trip levels, selecting INIT ALT = MAX and no STEP can overcome unnecessary low levels but that shouldn't the problem here.

 

 

 

The above suggestion resolves the issue.  Let me check a few more OFP's.

 

Regards

Ted

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...