Which offsets for eng.starter switch???

[PeterH]

Hi Potroh,

thanks for coming back so promptly.
Just overlooked that 174 is released. Of course I need to stick to the new code as I will depend on future updates as the one or the other thing may be improved over the time. Your position is much better though as to already having an almost perfect overhead logic with all bells and whistles.
Couldn´t I just append the logic part for the solenoid at the end of each starting routine?
It seems to me that PM here differenciates mainly between starting engines on ground or inflight. Rest seems more or less same as in last versions.

Here´s how I thought to do it:

//EngStart-Begin

StartActive1 = (fsonground and (ManEngStart1 = 0)) or ( not fsonground and (ManEngStart1 = 3) and (fsias > 180))

if StartActive1
if fsstartflag1 = 0
if bleed1ref > 0
fsStarter1 = 1
else
fsStarter1 = 0
endif
else
if fs1n2 > 50
manengstart1 = 1
endif
endif
else
if elecbus1 and drive1cover
fsstarter1 = 2
else
fsstarter1 = 0
endif
endif


if (ManEngStart1 = 0) and (fs1n2 >= 55) and fsstartflag1 then
cutout1 = 1
else
if (fsstartflag1 = 0)
cutout1 = 0
endif
endif

if cutout1 and fsstartflag1 and (ManEngStart1 = 0) then ManEngStart1 = 1



best regards

Peter

[Potrohkocsonya]

Of course I need to stick to the new code as I will depend on future updates as the one or the other thing may be improved over the time. Couldn´t I just append the logic part for the solenoid at the end of each starting routine?

Hi Peter,

Ok, but you may need to do some changes IF the default code changes again.

It seems to me that PM here differentiates mainly between starting engines on ground or in-flight. Rest seems more or less same as in last versions.

Yes and it does it wrong. It virtually says: "the engines can only be started in air if the switch is set to 'Flight' mode, which is completely wrong.
In reality one can start the engines either in GND OR FLT positions, depending on the circumstances.

You can have a 'windmill' start (in the FLT pos) if your speed is greater than 260 knots and your altitude is less than 24000 ft. (this is for the 800, other models have different recommended values).
If one engine is running and the other stopped and APU is not running, it will be a 'crossbleed start' which is not modeled in the default file either.

Anyway, first of all pay attention to the first line:
StartActive1 = (fsonground and (ManEngStart1 = 0)) or ( not fsonground and (ManEngStart1 = 3) and (fsias > 180))

there is a bug in it, namely that a '(' is missing. So change it to:

StartActive1 = (fsonground and (ManEngStart1 = 0)) or ((not fsonground and (ManEngStart1 = 3) and (fsias > 180))

Then change these lines for both engines:
old: if fs1n2 > 50 and if fsn2n2 > 50
new:
if (fs1n2 > 56) and cutout1
if (fs2n2 > 56) and cutout2

Add my lines after the //EngStart-End line.

If you want at least 'some' realism, also change the value
......and (fsias > 180))
to
......and (fsias > 260))

as no useful windmilling will ever happen at that slow speed.

Hope it helps
regards
Potroh

[PeterH]

Hi Potroh,

thanks very much. Will do as suggested and report results back.
BTW, which airplane model and, most of all, which airfile are you using in your sim? I´m using a modified PMDG 737 (mods from PM site) but having trouble in terms of trim. And hence the TO warning horn comes on when applying thrust. Their COG seems to be way off compared to PM CDU calculation.
That question has been raised quite often here in this forum, but sofar with no real good (realistic? as far as poss.) recommendation.

Thanks again and best regards

Peter

[Peter Dowson]

there is a bug in it, namely that a '(' is missing. So change it to:

StartActive1 = (fsonground and (ManEngStart1 = 0)) or ((not fsonground and (ManEngStart1 = 3) and (fsias > 180))

Actually you are miscounting the brackets. Your line now has the wrong number of (. Count them. There should always be an equal number of ( and ).

Please , why not send your critique to Enrico. As I understand it this is part of a developmnet release where he is experimenting a little with the correct logic. i'm sure your superior knowledge (Enrico has never professed to be an expert on aircraft matters) will assist him enormously, to our ultimate benefit.

Thanks & Regards
Pete

[Potrohkocsonya]

Actually you are miscounting the brackets. Your line now has the wrong number of

Hi Pete,

It's an honour.
And forgive me, but you are just partially right, as true, the second one is the wrong one with the extra bracket... And true, my mistake, as I simply copied the first one here.
This is Enrico's first line re the No.1 engine:

StartActive1 = (fsonground and (ManEngStart1 = 0)) or ( not fsonground and (ManEngStart1 = 3) and (fsias > 180))
and this is for the second:
StartActive2 = (fsonground and (ManEngStart2 = 0)) or ((not fsonground) and ( ManEngStart2 = 3) and (fsias > 180))

I think it speaks for itself if we compare the two.
Otherwise it is not a development release anymore, Enrico released it two days ago.

Please, why not send your critique to Enrico. As I understand it this is part of a developmnet release where he is experimenting a little with the correct logic.
i'm sure your superior knowledge (Enrico has never professed to be an expert on aircraft matters) will assist him enormously, to our ultimate benefit.

Well, I tried that but first of all I have no superior knowledge whatsoever.
I just built my sim, went through the relevant documentation and that' all. I'm also an ifr rated pilot in real world, which helps a bit, but perhaps just a little.

Enrico is truly busy all the time, I've sent him some requests a month ago when he started working on PM again.
But do not misunderstand me please, I do admire his work and would never criticize it (I am using PM since 2003) and wouldn't exchange it for anything else, specially that by now PM has some competition on the horizon.
But if something is wrong, I see no reason not to mention it, without any sarcastic feelings whatsoever.

I suppose you do remember, when Thomas Richter was writing some kind of advanced logic versions for the 737, many of us thought the process will result in all of us sooner or later to be able to have much better logics than the default one, but unfortunately Thomas went to the commercial way and his files were deleted from here and all over the net.
That's why I feel sad about it, because all enthusiastic users would truly deserve more, in case they don't want to spend months and months on doing their own versions - if they are capable doing it that is.

No words can express otherwise what you have been doing for the community for all those years, so let me say a trillion thanks here!

best regards
Potroh

[Peter Dowson]

And forgive me, but you are just partially right, as true, the second one is the wrong one with the extra bracket... And true, my mistake, as I simply copied the first one here.
This is Enrico's first line re the No.1 engine:

StartActive1 = (fsonground and (ManEngStart1 = 0)) or ( not fsonground and (ManEngStart1 = 3) and (fsias > 180))
and this is for the second:
StartActive2 = (fsonground and (ManEngStart2 = 0)) or ((not fsonground) and ( ManEngStart2 = 3) and (fsias > 180))

I think it speaks for itself if we compare the two.

Ah, yes, I see that -- but in that case you need to remove the excess '(' not add another, as you implied here:

there is a bug in it, namely that a '(' is missing.

Otherwise it is not a development release anymore, Enrico released it two days ago.

Oh, 174? I see it. Dated yesterday at the time of our exchange (i.e 24th v 25th). Odd. I was testing 173c for him and he said he was experimenting with this starter modification just a couple of days ago.

Enrico is truly busy all the time, I've sent him some requests a month ago when he started working on PM again.

Yes, he appears to be banging away at the code again. He seems to operate in rather hectic spurts. But I can't complain -- he's fixed several things I was suffereing from just over this weekend. Things on the RCDU have improved immensely (it's still not perfect) and my TCAS images on the Captain's ND no longer keep clearing and getting re-drawn -- something I've suffered from for a year or more.

But if something is wrong, I see no reason not to mention it, without any sarcastic feelings whatsoever.

Of course. But he doesn't read this Forum. You need to copy him at least -- as long as your mode is constructive he certainly won't take offense.

I suppose you do remember, when Thomas Richter was writing some kind of advanced logic versions for the 737, many of us thought the process will result in all of us sooner or later to be able to have much better logics than the default one, but unfortunately Thomas went to the commercial way and his files were deleted from here and all over the net.

No, that's really not true. I am still using pmSystems logic written by Thomas, and comparing it with the current 737 pmSystems logic you can see thatmost of what he did was embodied into the main releases. The only extra stuff I have in mine from Thomas was stuff he added specifically to operate with my implementation of the PFC overhead (which was unique in any case).

The current 737 (i don't know about the others) pmSystems files owes a lot to Thomas's contributions. I'm sure Thomas would also not agree with you on this. And I am still just as much in touch with Thomas as with Enrico.

Best Regards
Pete

[PeterH]

Hi Potroh,

have done the following mod. to PMsystem vers. 174 (hopefully it´s correct and according to your instruction):

//EngStart-Begin

StartActive1 = (fsonground and (ManEngStart1 = 0)) or ( not fsonground and (ManEngStart1 = 3) and (fsias > 260))

if StartActive1
if fsstartflag1 = 0
if bleed1ref > 0
fsStarter1 = 1
else
fsStarter1 = 0
endif
else
if (fs1n2 > 56) and cutout1
manengstart1 = 1
endif
endif
else
if elecbus1 and drive1cover
fsstarter1 = 2
else
fsstarter1 = 0
endif
endif

StartActive2 = (fsonground and (ManEngStart2 = 0)) or (not fsonground) and ( ManEngStart2 = 3) and (fsias > 260))

if StartActive2
if fsstartflag2 = 0
if bleed2ref > 0
fsStarter2 = 1
else
fsStarter2 = 0
endif
else
if (fs2n2 > 56) and cutout2
manengstart2 = 1
endif
endif
else
if elecbus2 and drive2cover
fsstarter2 = 2
else
fsstarter2 = 0
endif
endif

//EngStart-End

if (ManEngStart1 = 0) and (fs1n2 >= 56) and fsstartflag1 then cutout1 = 1
else
if (fsstartflag1 = 0) cutout1 = 0
if cutout1 and fsstartflag1 and (ManEngStart1 = 0) then ManEngStart1 = 1
endif
endif
if (ManEngStart1 = 0) and (fs1n2 >= 56) and fsstartflag1 then cutout2 = 1
else
if (fsstartflag1 = 0) cutout1 = 0
if cutout2 and fsstartflag1 and (ManEngStart1 = 0) then ManEngStart1 = 1
endif
endif

The CutOut1 and CutOut2 Idefined in sysvar.txt:

56CC .0 SEC1Fault //Airbus
56CC .1 SEC2Fault
56CC .2 SEC3Fault
56CC .3 ELAC1Fault
56CC .4 ELAC2Fault
56CC .5 FAC1Fault
56CC .6 FAC2Fault
56CD .0 CutOut1
56CD .1 CutOut2
56CD .2 ADR3
56CD .3 IR1

Hope I did it right also the "endif"
One question though: Shouldn´t I omitt the line from your proposed code:

if cutout1 and fsstartflag1 and (ManEngStart1 = 0) then ManEngStart1 = 1

as, to my limited understanding, that code is already implemented in PMsystem 174 some lines above.

Does the number of "endif" have to correspond to the number of "if" or does the "else" statement that already. (Can I consider those as some kind of brackets?)

Thanks and best regards

Peter

[Potrohkocsonya]

Hi Peter,

The easiest is, if you just modify the default in a single line (for both engines).

if fs1n2 > 50
manengstart1 = 1
cutout1 = 1
endif


if fs2n2 > 50
manengstart2 = 1
cutout2 = 1
endif

just place the cutout lines.

And as many endifs as many ifs, with the exception if the expression is in a single line with no 'else'.


regards
Potroh

[Potrohkocsonya]

Hi Pete,

Of course. But he doesn't read this Forum. You need to copy him at least -- as long as your mode is constructive he certainly won't take offense.

I do agree. But you can hardly say I had a ‘tendency’ to be not constructive, as I am attending this forum since it was born and I’m used to be on the ancient one too, without saying or mentioning anything that wouldn't be constructive. So, it is not a tendency with me, it was a single remark and nothing else. I repeat: I admire the entire PM idea and Enrico's creativity!

The current 737 (i don't know about the others) pmSystems files owes a lot to Thomas's contributions. I'm sure Thomas would also not agree with you on this. And I am still just as much in touch with Thomas as with Enrico.

True. I know that. Thomas’s contribution was priceless a few years back. But you mention using his code partly even today (and many of us do the same of course), but the truth is that only the most relevant things remained in the default file out of Thomas’s work, and a lot did not survive.
His pumps logic, bleed, etc. are represented much simpler again in the stock file.

The problem is that Enrico clearly stated when pmsystems started that he is giving the base only, the mere fundament to be built upon and I also strongly feel it wouldn’t be his task to provide entire thing. But for years now nobody seems to be gracious enough to share more advanced code, specially towards those, who are unable to it themselves.

best Regards
Potroh

[PeterH]

Hi Potroh,

thanks again for your reply.
Now it´s much more clear to me.

Since you mentioned Thomas Richters 737NG program (extended functionality to PMsystem) I´m puzzled to what extend I should/could use it in combination with PMsystem.

Sofar one had to erase some code from PMsystem when Thomas´737NG was in use. Unfortunately haven´t seen any note from Thomas telling whether it is still required to do so also for latest releases of PMsystem.

I hope I´m not a nuissance to you when bringing up one of my question from some msg before concerning the aircraft model / airfile you are using.


Thank you very much

very best regards

Peter