Engine start and idle detent question
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For us who doesn’t have any hardware idle detents, just slam the throttle to full, press alt+i (or click the clickspot), pull back to idle. It’s neither less nor more realistic than looking for 50% or 75% movement, and it becomes a very simple move (and it will not hurt the jet in the sim).
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you need to check that the 'idle cutoff" setting is not activated in the bms config.
this options lets us pit builder omit the alt I keystroke and make theengine start as per the real life procedure which is according to position of the throttle handle.if it enabled and you don’t have a throttle gate like cockpit builders have, then you might have this problem…
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I don’t have cutoff enabled in configuration. With it enabled RPM actually rises without having to do anything.
This is from T.O. GR1F- 16CJ - 1CL - 2:
3. Throttle - Advance to IDLE at 20 percent rpm minimum.
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16. Throttle cutoff release - Check.It seems to me that better modelling of this procedure without use of an actual idle detent would be to push the throttle forward then return it to idle. I think that would better simulate pushing the throttle out of detent.
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that’s what i do
alt I
push throttle forward then backi’m not sure exactly how you’re supposed to do it but it always worked for me
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I don’t have cutoff enabled in configuration. With it enabled RPM actually rises without having to do anything.
That is incorrect. it does only if your throttle is past the detent set in the UI
This is from T.O. GR1F- 16CJ - 1CL - 2:
Tbh, we don’t care, please rather check the BMS Dash1
It seems to me that better modelling of this procedure without use of an actual idle detent would be to push the throttle forward then return it to idle. I think that would better simulate pushing the throttle out of detent.
Nope, the idle cutoff option from BMS config is 100% realistic, if set correctly. But to be able to use it you need strong physical detents to be sure that you don’t inadvertently go past the detent as you’re reducing throttle in flight. With the option enabled and going past the detent you will shut the engine off.
The ALT i is just a software detent overcoming that issue. it’s a compromise preventing ppl to complain that the engine shuts off without “obvious” reason
Although in real, the misnamed “idle detent” with is the cutoff lever must be depressed only to lift the throttle handle vertically to go past the idle point and therefore shutting the engine down.
The cutoff lever does not have to be depressed when you move the vertical throttle (in cutoff) to horizontal position in idle, which ignites the engine past JFS
left idle, right cutoff -
Well, I gave my experience after 45 minutes of testing each and every possibility. You can take it or leave it.
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I tried every variation of throttle position from idle to 75% and RPM would only rise if I used the method I described.
In the actual jet the throttle is “maneouvered” into idle detent and RPM rises:
The question is, does that idle detent position correspond to idle throttle on a standard stick? Because if it does I would expect Alt+i to work without throttle movement.
Always funny to see a cockpit that I know so well in real. Also note that the countermeasures panel is not shown at all!
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Well, I gave my experience after 45 minutes of testing each and every possibility. You can take it or leave it.
Apologies mate. I thought I 'd share my 15+ years of experience with the sim, and the pit I built around it to try to answer your question.
But if you gave it 45 minutes testing and made up your mind, all’s good
Have fun -
if the engine isn’t starting you’re doing it wrong.
possibilities:
your throttle isn’t bound
you’re not doing it quickly/slowly enough
you rebound idle detent
you don’t have idle detent and are using the non software thing but doing it incorrectly somehowdon’t you think everyone would kind of notice that they can’t start the jet since 4.33 u1
i mean you do that every mission after all unless you’re a filthy casual
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@Red:
Nope, the idle cutoff option from BMS config is 100% realistic, if set correctly. But to be able to use it you need strong physical detents to be sure that you don’t inadvertently go past the detent as you’re reducing throttle in flight. With the option enabled and going past the detent you will shut the engine off.
Well…more like 80% realistic…
In a real jet(s), the detent/latch/lock/lever, etc is actuated first, then the pilot pulls the lever aft WELL PAST the detent to engine cut off to shut down the engine. In BMS with Engine Idle Cutoff enabled in Config, the detent and the engine cutoff are located in the same part of the throttle stroke which is not realistic. Even with a rock solid detent (9mm shell casing in my case), the idle detent setting in setup/controllers can still drift a little bit eventually causing inadvertent inflight engine cutoff (or engine that won’t spool down completely to idle RPM) when pulling the throttle to idle against the hard detent. As currently modeled, there is virtually no margin for error between “idle detent” and engine cutoff. To add a small margin of error against inadvertent inflight engine shutdown for sim pilots using a hard detent throttle, I posted the following suggestion in joysticks/CH forum (note step 3):
The combined “engine idle detent/cutoff” as currently modeled in the sim needs to be corrected by separating these two functions into two different settings. One for the detent/latch/lock/lever, etc. (essentially idle RPM) and one for the cutoff of the engine. I posted a more detailed explanation here.
F1
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I’m a little puzzled by idle detent and throttle inputs, and I’m not sure whether this is normal behaviour or it indicates an issue of some kind.
I select JFS2 and RPM rises to 20%. I set throttle to approximately 50% and press Alt+i. The SEC light illuminates briefly and then goes out. RPM does not rise. I then reduce throttle to idle and then return it to 50%. RPM then rises.
It doesn’t seem to come out of idle detent without significant throttle input.
Try this or similar instead of Alt i (how to push throttle forward to light off the engine):
F1
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I created a video showing the procedure with idle cutoff first unchecked and then checked.
Note that with it unchecked I advance the throttle, Alt-i, then when RPM doesn’t rise above 20% I return throttle to idle and advance it again to approximately 50%, at which point it does rise.
Then in the second example with idle cutoff checked I do no more than select JFS 2.
MS Sidewinder FFB.
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Checking Idle cutoff in the config is, if performed as the only step, a simple case of misconfiguring the software and blaming it on the software.
You also need to set the position of the detent, and by default it is positioned at the very back of the throttle movement. Which means the software considers you already to have advanced the throttle over the detent.
If you want it to work you need to also set the detent position in setup, by positioning the throttle just aft of the detent position and right clicking the set AB button. Left clicking sets the green AB line, right clicking the red IDLE line.
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I would expect Alt+i to work without throttle movement.
That’s the key word, expect. BMS doesn’t function how one expects. The user can resolve this problem through patience in having the software change or by altering their understanding. I recommend the latter as it is more timely.
The idle detent logic is simple to grasp if the proper effort is put forth. There are only two elements at work: if the idle detent command is given and what is the throttle axis value at that time. The user has only these two inputs to concern himself with and in the proper order: axis first, command second.
At the moment the command is given, the program looks at the axis value. If the axis value is > X% then it will move the throttle to the working range. If the axis value is <y% then=“” it=“” will=“” move=“” the=“” throttle=“” to=“” off.=“” change=“” in=“” setting=“” depends=“” entirely=“” on=“” axis=“” value=“” <em=“”>at the time the idle detent command is given. In this way we can see that the idle detent command can do two actions (three if one includes doing nothing) and this decision is entirely depending on the throttle controller axis value which is set immediately before the command is given.
If the user wants to advance the throttle then he must set an axis value consistent with this desire first and issue the detent command second. (>X%)
If the user wants to reduce the throttle then he must set an axis value consistent with this desire first and issue the detent command second. ( <y%)<br>It would be nice for general information to have exact values of X and Y for completeness.</y%)<br></y%> -
I have 1 view on that video, which I think speaks for itself.
The video explains clearly the issue. I can’t do any more than put the time and effort in to create a video showing what the issue actually is. But I feel that no one is actually listening to what I’m saying, or, indeed, showing.
I don’t have a detent, I’m not enabling cutoff other that to demonstrate that the engine spools up without using Alt-i when I do have it enabled.
Without cutoff enabled in config I have to push the throttle forward, Alt-i, pull it back to idle and push it forward again.
Let me be absolutely clear, and, again, this is with a throttle without a detent:
Example A
- push throttle forward to 50%
- Alt-i
- back to idle
- push throttle forward to 50%
That is the only way I can increase RPM over 20%
Example B
- I don’t have to do a thing with throttle or Alt-i - RPM increases past 20% all by itself
I was told that’s incorrect, but if you watch the video, that’s exactly what happens.
I wanted to understand what exactly is happening. That was the purpose of opening this thread. I like to understand things. However I will just document it as I have experienced it, which is not optimal.
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I have 1 view on that video, which I think speaks for itself.
The video explains clearly the issue. I can’t do any more than put the time and effort in to create a video showing what the issue actually is. But I feel that no one is actually listening to what I’m saying, or, indeed, showing.
I don’t have a detent, I’m not enabling cutoff other that to demonstrate that the engine spools up without using Alt-i when I do have it enabled.
Without cutoff enabled in config I have to push the throttle forward, Alt-i, pull it back to idle and push it forward again.
Let me be absolutely clear, and, again, this is with a throttle without a detent:
Example A
- push throttle forward to 50%
- Alt-i
- back to idle
- push throttle forward to 50%
That is the only way I can increase RPM over 20%
Example B
- I don’t have to do a thing with throttle or Alt-i - RPM increases past 20% all by itself
I was told that’s incorrect, but if you watch the video, that’s exactly what happens.
I wanted to understand what exactly is happening. That was the purpose of opening this thread. I like to understand things. However I will just document it as I have experienced it, which is not optimal.
It’s private……
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I have 1 view on that video, which I think speaks for itself.
The video explains clearly the issue. I can’t do any more than put the time and effort in to create a video showing what the issue actually is. But I feel that no one is actually listening to what I’m saying, or, indeed, showing.
I don’t have a detent, I’m not enabling cutoff other that to demonstrate that the engine spools up without using Alt-i when I do have it enabled.
Without cutoff enabled in config I have to push the throttle forward, Alt-i, pull it back to idle and push it forward again.
Let me be absolutely clear, and, again, this is with a throttle without a detent:
Example A
- push throttle forward to 50%
- Alt-i
- back to idle
- push throttle forward to 50%
That is the only way I can increase RPM over 20%
Example B
- I don’t have to do a thing with throttle or Alt-i - RPM increases past 20% all by itself
I was told that’s incorrect, but if you watch the video, that’s exactly what happens.
I wanted to understand what exactly is happening. That was the purpose of opening this thread. I like to understand things. However I will just document it as I have experienced it, which is not optimal.
Just a guess…
Example A, #3, if not already done so, open Windows Joy Properties and confirm that the throttle axis graphic is not around 50% when the throttle lever is full aft. If not, fix issue then try again.Example B: as you have discovered, Alt I is not needed if Idle Detent is enabled in Config. However, “all by itself” (no throttle input) is definitely incorrect. If throttle not properly calibrated, engine may autostart with no additional input.
F1
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Well…more like 80% realistic…
Nope, I stand by what I said. The idle cutoff code in BMS config is made to accurately represent the very same way of the F-16. All cockpit builders here will tell you that.
You obviously (software options won’t get you a cutoff lever, throttle gate, …) need to have the hardware as I said earlierIn a real jet(s), the detent/latch/lock/lever, etc is actuated first, then the pilot pulls the lever aft WELL PAST the detent to engine cut off to shut down the engine
. Exactly how we pit builder do it, with the cutoff code
In BMS with Engine Idle Cutoff enabled in Config, the detent and the engine cutoff are located in the same part of the throttle stroke which is not realistic. Even with a rock solid detent (9mm shell casing in my case), the idle detent setting in setup/controllers can still drift a little bit eventually causing inadvertent inflight engine cutoff (or engine that won’t spool down completely to idle RPM) when pulling the throttle to idle against the hard detent. As currently modeled, there is virtually no margin for error between “idle detent” and engine cutoff. To add a small margin of error against inadvertent inflight engine shutdown for sim pilots using a hard detent throttle, I posted the following suggestion in joysticks/CH forum (note step 3):
Never happened to me in 10+ year of using BMS and my pit. You must have calibration issues (some using auto calibration for the Cougar might see that issue)
In that case, the problem is not the way BMS coded the cutoff, but rather the user way of calibrating his throttle, which is outside the scope of the BMS code -
@Red:
Nope, I stand by what I said. The idle cutoff code in BMS config is made to accurately represent the very same way of the F-16. All cockpit builders here will tell you that.
You obviously need to have the hardware as I said earliernot all… I can only conclude you did not read the post, and assumed it was the same issue as above (it is not).
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I quoted the part I’m replying to Bw (which was a reaction to a post of mine), isn’t that obvious enough?
I haven’t seen any VP member complaining about that bit of code. It does work beautifully if implemented correctly along suitable hardware