Speed restriction gets deleted

[tcas_climb 45]

Hey guys, when you select direct to a waypoint that is below 10000ft, for example the IAF for an instrument approach while you are at cruise altitude, is it normal for the FMC to delete the 240/10000 restriction on the descent page?ok, well it seems that it gets deleted after selecting an instrument approach procedure with hard altitude and speed restrictions at the fixes, and i cannot re-enter the speed restriction in the descent page.....any ideas as to why this is so or if it is normal?

[ray hughes 165]

It is probably because you are busting the speed restriction. If you want to add in the condition for say the speed of 240 knots or 250 knots or below in the hard coded approach then I think you have to modify it to show 240B/ or 250B/ . (at or below)Does that answer the question?

[tcas_climb 45]

no thats not it, im talking about the speed restriction on the DES page, normally for climbout its restricted automatically to 250 knots below 10,000ft, and for descent its default is 240 below 10,000ft, i have no idea why it has disappeared and now when i try to enter 240/10000 in the restricting field on the DES page and press EXEC it disappears, checking the legs page the FMC has soft speed predictions well over 240 knots at altitudes like 6000ft

[Chaos81 110]

What route were you on when this happened? I just tried it quickly on a flight from KLAX-KSAN and couldn't get it to happen. Took off, used heading select to aim towards KSAN, once level at 11K, I went direct CIHJI but the restriction didn't disappear for me. I deleted it manually, then reentered it, and all worked as expected. Maybe I need a higher cruise altitude.

[tcas_climb 45]

cruising at FL340MKJS ALORA UG442 UCL UL212 LITGU UL674 XORIL UJ83 FRISH A321 HRV J58 AEX CQY6 ILS17L KDFWoh i figured it out, i had in a step climb on the cruise page, (360) (on a side note, my optimum altitude is FL381 and its not predicting a step, and when it does it says STEP POINT UNABLE even when im more than 500 miles from the T/D, is that because the fuel saving penalty is 0.0%?), i deleted the step climb and the restriction came back.

[NGXfanatic 85]

cruising at FL340MKJS ALORA UG442 UCL UL212 LITGU UL674 XORIL UJ83 FRISH A321 HRV J58 AEX CQY6 ILS17L KDFW oh i figured it out, i had in a step climb on the cruise page, (360) (on a side note, my optimum altitude is FL381 and its not predicting a step, and when it does it says STEP POINT UNABLE even when im more than 500 miles from the T/D, is that because the fuel saving penalty is 0.0%?), i deleted the step climb and the restriction came back.

Hi, I have the latest hot fixes installed, in fact I reinstalled the NGX from scratch with the latest installer that has the hotfixes "baked" in. I'm seeing the same confusing messages from the FMC in regards to step climbs and the deletion of the speed restriction on descent, and wanted to know if PMDG knows about this issue and plans on fixing it. For instance, during a carefully planned pre-flight routine for a 3 hour flight, the FMC predicts one step climb in the later part of the flight (with greater than 200NM to go before TOD). Strangely enough, at about 25,000 feet during the climb, the FMC asks for me to bypass the expected initial cruise level (34000ft) and climb straight to the step climb altitude (36000ft), hundreds of miles before the original computed step point. See screenshot below. I ignored the request to climb to FL360, and settled into the cruise at FL340. And at that point, step point NOW changes to UNABLE. This is a first for me, previously the bug manifested itself with just the unable message, but anyhow, I made a note on the ground of the waypoint I can expect to climb to FL360 and will climb at that point, regardless of the FMC warning since I will be more than 200 nm from TOD. I just want to know if PMDG is aware of this issue, and can they confirm if this is a glitch or the real world behavior of the NG? Are others seeing this behavior?