Starting engines

[Alan_A 1,650]

1 hour ago, downscc said:

I agree, I have plenty of saved scenarios, each one unique in the location and state of the aircraft.  Engine starts always work, after I've been cussing at it for about 12-15 sessions.  It seems like it took weeks for me during beta testing to get to the point where I could start an engine on demand.  Don't blame it on a bug, or a saved scenario or anything other than experience or lack thereof.

Hey, Dan, I understand what you're saying, but I really think something else is going on here.  My sim background is a little odd - I'm not a PMDG veteran, I've spent much more time on the A2A fleet, so I get it about the art (not science!) of starting radials. This is different - it's an either/or.  Option A, load cold-and-dark (either from the scenario screen or over my cold-and-dark default flight), engines will crank but not start.  Option B, load over the default flight after starting the default aircraft's systems, run exactly the same startup procedure, and the engines fire (generally with one balked start that then starts properly on the second attempt).

I had a hunch, so I just tried something else out.  I loaded the DC-6 from the scenario screen - didn't load the default flight, but I didn't change it either, still a cold-and-dark setup.  Then I selected "ready to taxi" and let the DC-6 fire up.  After that, I selected "cold and dark" and everything shut down.  Then I had the AFE run the before start checklist.  And then I started the engines.  And they fired.

So what seems to be going on is that, for whatever reason, the DC-6 can't start correctly when it's loaded in a cold-and-dark state from the scenario screen.  Something seems to be glitching - my first guess is something to do with the fuel system, since the cranking happens OK but the engines don't fire.  If I load over an engines-running defaut flight, the problem doesn't present itself.  And if I set the aircraft at "ready to taxi," with engines running, then revert to cold-and-dark, the problem seems to clear itself.

I'm not technically qualified to say more than that, and I've only ever participated in one beta test (for the Manfred Jahn C-47 v3).  So I'm pretty much at the limits of what I can contribute.  If the developers want to say that it's a requirement to load over an engines-running default flight or to "clear" the engines by running through the ready-to-taxi state, neither of those things is hard to do.  If there's something here that they want to look at, I hope this points them in a useful direction.  

[signmanbob 592]

I love this DC-6, but I'm finding that my engines don't really start correctly.

I always set it on realistic start and can always start them, but I don't believe they are starting like the real ones.

In order to start each engine, I have switch the primer at the count of "6" and the mags to "Both" at the count of "9" so that it is already on before "12".

When I seen them start the engines on the Just Planes video, they switch the mags to "Both" at around "14". 

If I don't have my mag to "Both" by the time it reaches the count of "12", my engine does not start.

I believe that is a bit of a problem, but I can get it started every time by switching the mag to both at the count of "9", so I'm not too worried about it.

 

Bob
 

[Wothan 173]

As told elsewhere her in the PMDG forum, the start of the PMDG DC-6B is scribted.

There is a certain logic that must be true for a succesfull start:

Boost pump-On AND Engine selector to Req. engine AND Start switch-On (Starts timer1 controlling 3,6,9,12 Blade calls) AND Primer switch-ON AND Magneto-Both AND Boost switch-On AND Timer1 equals "12 Blade" Call => Initiate Start (Starts timer 2, which is a very short set timer) => Mixture set to Auto rich before timer2 runs out.

 

Had the start not been scribted, then the use of Primer would be dependent on OAT, engine temperature and by scheduling the switch On/Off You could conrol amount of priming and thus keep the engine running on Primer. Also actually start of engine combustion could happen anytime after magneto is set to Both and Boost set to On and not just exactly at the "12 Blade" Call. Keeping the engine running on Primer alone would be difficult for prolonged time, but possible.

Over primimg and premauter movement of the mixture lever would also led to flooding, requiring a fuel clearing procedure. Spark plug fouling would also be an issue.

All this though seems not to be simulated.

[PMDG777 231]

4 minutes ago, Wothan said:

As told elsewhere her in the PMDG forum, the start of the PMDG DC-6B is scribted.

There is a certain logic that must be true for a succesfull start:

Boost pump-On AND Engine selector to Req. engine AND Start switch-On (Starts timer1 controlling 3,6,9,12 Blade calls) AND Primer switch-ON AND Magneto-Both AND Boost switch-On AND Timer1 equals "12 Blade" Call => Initiate Start (Starts timer 2, which is a very short set timer) => Mixture set to Auto rich before timer2 runs out.

 

Had the start not been scribted, then the use of Primer would be dependent on OAT, engine temperature and by scheduling the switch On/Off You could conrol amount of priming and thus keep the engine running on Primer. Also actually start of engine combustion could happen anytime after magneto is set to Both and Boost set to On and not just exactly at the "12 Blade" Call. Keeping the engine running on Primer alone would be difficult for prolonged time, but possible.

Over primimg and premauter movement of the mixture lever would also led to flooding, requiring a fuel clearing procedure. Spark plug fouling would also be an issue.

All this though seems not to be simulated.

Sorry but source for that? As told in the forum by who? A member of PMDG or someone who thinks they know? Because Robert's pre-release thread for the DC-6 pointed to all of that being simulated.

[MatzeH84 81]

For me that makes sense, because if you check what Finn wrote in the sim, you will see it's the way the DC6 starts. No real simulation of the things going on in the background, it is just checked if all variables needed are true.

To be honest, for a product at this price and coming from PMDG, while they didn't have to implement time consuming stuff like a full FMS and autoflight system, they could have spend more time to get this done better. I'm a bit disappointed in this regard. Especially if you see the direct competitor costs less and does better. Maybe PMDG should stick to jets, that's where they are really top notch.. But truly simulating an old radial engine is a totally different story.

After all I guess that for most people the way PMDG did it on this aircraft is sufficient, for myself however it's, as said, a bit disappointing, especially regarding the price.

[Wothan 173]

44 minutes ago, PMDG777 said:

Sorry but source for that? As told in the forum by who? A member of PMDG or someone who thinks they know? Because Robert's pre-release thread for the DC-6 pointed to all of that being simulated.

I´m very sorry - I see that this easily can be misunderstood and be seen as a matter of fact, so to re-phrase...

As told elsewhere her in the PMDG forum, the start of the PMDG DC-6B is scribted.

As discussed elsewhere here in the PMDG forum, the start of the PMDG DC-6B seems scribted.

And yes - this is what I THINK I know !

After many, many starts under varying conditions (OAT between ÷30 - +50° C / Cold and warm engines), the above logic seems clearly evident, but I would happy if You could prove me wrong.

My entire point is not to negativly critisise th PMDG DC-6B, cause I actually find it nice for what it is. But I think that just like others who are used to the incredible deep systems simulation we have been so used with from PMDG, the DC-6B does not go quite to the depth that many of us had expected from PMDG also the price tag taken into consideration.

(MatzeH84 manage to post before me :-))

 

[PMDG777 231]

41 minutes ago, Wothan said:

I´m very sorry - I see that this easily can be misunderstood and be seen as a matter of fact, so to re-phrase...

As told elsewhere her in the PMDG forum, the start of the PMDG DC-6B is scribted.

As discussed elsewhere here in the PMDG forum, the start of the PMDG DC-6B seems scribted.

And yes - this is what I THINK I know !

After many, many starts under varying conditions (OAT between ÷30 - +50° C / Cold and warm engines), the above logic seems clearly evident, but I would happy if You could prove me wrong.

My entire point is not to negativly critisise th PMDG DC-6B, cause I actually find it nice for what it is. But I think that just like others who are used to the incredible deep systems simulation we have been so used with from PMDG, the DC-6B does not go quite to the depth that many of us had expected from PMDG also the price tag taken into consideration.

(MatzeH84 manage to post before me :-))

 

I wasn't doubting you or anything like that, I certainly don't have any evidence for or against, I just wanted to caution against your wording because it sounded like it was fact, not hypothesis.

[Alan_A 1,650]

I have no problem with a scripted start - a lot of developers do this.  In fact, I'm not 100 percent sure, but I think A2A may be the only developer to model a radial engine at the system level (i.e. individual cylinders, fuel in the primer lines, ambient temperature and moisture effects, etc.)  And it's taken them years to get there - their early radials weren't so detailed.  

It's possible for a scripted start to be completely immersive - I'd point to the Manfred Jahn C-47 v3, where the primers actually work as firing triggers, but there are contingencies for things like flooding the engine.

If Finn is right, and the 12-blade count is a strict timer limit, that might be something PMDG could take a second look at - only because, as far as I've come to understand it, radial starts aren't so strictly timed.  There are conditions that need to be met and ways to go wrong, but there's also some leeway - enough that, as we've even seen in this thread, there are arguments about how many blades to turn before letting the mags in.

The current routine is fine, now that I've got it working and I know how it works - and the timing limitations (if there are) don't get in the way.  Something looser would be even more fun - but it's definitely a luxury request.

And if I've gotten any or all of this wrong, the luxury request can be withdrawn.

[Wothan 173]

10 minutes ago, Alan_A said:

I have no problem with a scripted start - a lot of developers do this.  In fact, I'm not 100 percent sure, but I think A2A may be the only developer to model a radial engine at the system level (i.e. individual cylinders, fuel in the primer lines, ambient temperature and moisture effects, etc.)  And it's taken them years to get there - their early radials weren't so detailed.  

It's possible for a scripted start to be completely immersive - I'd point to the Manfred Jahn C-47 v3, where the primers actually work as firing triggers, but there are contingencies for things like flooding the engine.

If Finn is right, and the 12-blade count is a strict timer limit, that might be something PMDG could take a second look at - only because, as far as I've come to understand it, radial starts aren't so strictly timed.  There are conditions that need to be met and ways to go wrong, but there's also some leeway - enough that, as we've even seen in this thread, there are arguments about how many blades to turn before letting the mags in.

The current routine is fine, now that I've got it working and I know how it works - and the timing limitations (if there are) don't get in the way.  Something looser would be even more fun - but it's definitely a luxury request.

And if I've gotten any or all of this wrong, the luxury request can be withdrawn.

I agree with You Alan_A...

Just because A2A goes deeper, PMDG does not have to. The immersion factor could be as good with less, if done more random.

The Primer switch should not timed in the ON position, but kept on as lomg as the Primer is held in ON position with the mouse, or maybe even made "sticky" in the ON position in order to allow mouse clicks inbetween on other switches and levers.

The engine start randomness should then rely on Engine temperature (f.ex Oil temp.), OAT and the time the Primer is held and should happen either right away, or some time equal to somewhere between 9 and 18 Blades, after which the engine should be deemed flooded and a restart of the procedure required.

Since direct control of the mixture lever via hardware controller axis isn´t used anyway, holding the Primer could adjust the flightsims internal mixture setting to the point of being combusible (stoichiometric mixture, which is about 0,0825 for rich mixture and 0,0779 for lean). The Primer switch will then increase/ecrease the mixture ratio from 0,000 towards 0,1000, the rate is then dependent on Primer switch position, engine temp and OAT. This offcourse happens behind the scene with the DC-6 mixture lever in Cut-off position. The engine should then start when the value reaches around 0,0700 - 0,0850 mixture ratio. By toggling the primer ON/OFF around this setting can then keep the engine running on Primer and the engine will run uneven as the mixture goes up and down until moving the mixture lever into auto rich takes over and keep the engine run even.

The above is just a suggestion on how it could be done.

 

[downscc 1,327]

I'm not sure it is entirely scripted... there is a random variability but PMDG will be the first to admit it is not realistic.  In the DC6 at least two and preferably three people are involved in  engine start.  It is a big deal with lots of money at risk.  PMDG purposely simplified the procedure so it can be done with one person using a pointer device (trackball or mouse),  this especially is apparent in the operation of the prime, start, interlock and boost switches. I'm okay with that.

[Alan_A 1,650]

1 hour ago, downscc said:

In the DC6 at least two and preferably three people are involved in  engine start.  It is a big deal with lots of money at risk.  PMDG purposely simplified the procedure so it can be done with one person using a pointer device (trackball or mouse), 

Oh, I think that's fine - I don't know of anyone that does a fully realistic multi-crew engine start.  Maybe that's something for FS2Crew to think about if Bryan wants to get his hands deep in engine oil...  My only thought is that slightly looser timing would capture that radial-style unpredictability - will it start?  Have I flooded it?  No, wait, there it goes...  But there's such a huge amount to like about this aircraft that I don't see it as any kind of a big deal.  If it stays where it is, I'm good.

[scandinavian13 5,192]

37 minutes ago, Alan_A said:

get his hands deep in engine oil

Hands? Man...whoever gets only hands deep with a radial is getting off easy...

[Alan_A 1,650]

Just now, scandinavian13 said:

Hands? Man...whoever gets only hands deep with a radial is getting off easy...

Well, I had to start somewhere... and not get too anatomically explicit, either.  This is a family forum, right?  

[scandinavian13 5,192]

Just now, Alan_A said:

Well, I had to start somewhere... and not get too anatomically explicit, either.  This is a family forum, right?  

haha - true.

Either way, there's a reason I have a long sleeve shirt in my closet called the "DC-3 shirt," despite it having no branding or anything else related to aviation on it. Just oil spatters...

[Alan_A 1,650]

3 minutes ago, scandinavian13 said:

despite it having no branding or anything else related to aviation on it. Just oil spatters..

Those who get it, will get it...