After T/O if ATC tells you to climb to your chosen FL, does this overide the altitude restrictions? This same question applies to descent. I had this yesterday just before TOD in the 737 Max when i was told to descend to 3000ft at a certain waypoint within the arrival contravening the other waypoint restrictions.
In what instance would this be able to be instructed if correct.
IFR Rules: YES
As mentioned above, ATC instructions overrule published restrictions.
Mainly for traffic avoidance, better traffic flow for a unique reason, or visibility- weather reasons for certain aircraft.
However, with the sim’s native ATC, I would consider whether or not to follow that ( for example: is the instruction a bug), particularly so if you would have to climb again.
In my experience in the sim, descent instructions usually work out to follow the restrictions - there is no compulsion to descend immediately to the assigned level as long as you get there at the cleared level - choose a reasonable rate of descent. (As long as you’ve started a descent the sim won’t mind!).
However I usually use a third-party ATC programme which almost always clears you to each restriction as you go along. I also use VNAV where the aircraft has it, which avoids “guesswork”. However, for climb it currently ignores level restrictions unless I use VNAV. But again the programme won’t complain!
ATC is a complex issue, and MSFS in either form doesn’t make a very good job of it.
Thanks very much for the information. That helps. Luckily it wasn’t a climb again instruction. Just learning the in sim 737 max, airliners are a very different kettle of fish. I was following Jon Becketts youtube video last week and was having an instruction free go myself. In his video his TOD did not come up. Mine did and so was also wondering why mine did and his did not. Which, if you don’t mind me asking, are the most important bits of info in the Max to ensure you get a TOD marker for VNAV to descend automatically? I used simbrief to import FP.
Thanks Terry, good to have the extra points of view.
It should always be there if you completed the FMC with your arrival information.
You do need to have the desired descent altitude dialed in the AP before TOD.
Any new ATC instruction amends or replaces previous instructions. So the new lower or higher restriction are what you need to comply with.
I would however also always question ATC instructions in real life when they contradict what your situational awareness tells you 
ATC once told me to fly a certain heading, and then forgot about me. The heading and altitude would have lead to CFIT if I had blindly accepted the instruction.
But of course in real life we do have the option to simply ask for clarification and as in my case receive revised instructions immediately. The controller was quite obviously relieved of the outcome. Almost as much as I was
Yes it is very proper to confirm any odd request with ATC, I should have indeed mentioned that.
Hard to do in the sim though!
Check your flight plan. If there are any discontinuities (like before an approach) before the next decent altitude restriction, VNAV will not be able to calculate a TOD. This is true in GA planes as well like the Garmin avionics planes.
Thanks, I was wondering if things were somehow very different with respect to the 737 max since I have at last decided to brave airliners! Particularly since I never seem to get all the performance data correct. I also could not get the copilot Baro to switch to Std. I wondered if that’s a thing with the Max.
Short answer, yes.
But lately I’ve noticed (in FS2020 anyway) that when using VNAV in my descent, thereby respecting the restrictions, ATC doesn’t complain. Very occasionally, I get told to expedite, then immediately told to descend to the altitude I was going to anyway.
I never really follow ATC altitude vectors. Climb to FL210 at 12nm from airport? Yeah no thanks lol. The FMC should automatically follow altitude restrictions, and i just let it do it’s thing.