Stoopind NOOB question about displayed RPM:
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…on some ac ab engages from 101%-103%, i.e. mil = 1-100%RPM and then the ab lights at higher rpms. On the F-16CM in stock campaign it goes to 107-108% and then ab, on MiG-19S the ab lights at 100% rpm and does not go above 100%. Is the universal definition of mil not 1-100% rpm, or is it supposed to be diff between diff ac? I can’t figure-out how to tell if I’m in ab without using external views (or based on fuel flow). I’m sure it’s prob in the -1 but I haven’t found the answer, yet…
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I found this confusing when I was new to BMS too… I guess the idea is, that number is calibrated to whatever the ac is displaying on its instrument.
And, among the F-16 blocks, there seems some attempt to calibrate the rpm gauge to power output… so eg. 100% on an older block is ~92% on a newer block.
I’m also curious about this… I assume this modelling differences among the RL planes… is this so vipers of different blocks can fly formation easier? (Is that common?)
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Meant to add…
Check out
https://github.com/mrkline/bms-burner
to get an audible or visible feedback when pushing through the AB detent.I added similar audio feedback, for my mouse-as-throttle prototype
https://github.com/arithex/DragWheel(I know I know … the real plane doesn’t have such feedback … but if the real plane offers the tactile sensation of moving the throttle through a detent, and our $40 desktop joysticks don’t have that, then a little sound-effect crutch can help fill that gap in the overall experience.)
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our f16s in bms have three different power trains throughout the different blocks. Just read up on those different guys, i think we got the 110, the 109, and the 220- my memory is full of down wind disavowals and voluntary forgetfulness so dont quote me, heh.
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our f16s in bms have three different power trains throughout the different blocks. Just read up on those different guys, i think we got the 110, the 109, and the 220- my memory is full of down wind disavowals and voluntary forgetfulness so dont quote me, heh.
Yes, this is basically correct. It is all dependent on the engine that is installed on the particular F-16 block you’re flying. The USAF flies the F-16C Blocks 30/32, 40/42 & 50/52. The difference between the “Zero” & “two” is Zero denotes GE engines and Two denotes Pratt & Whitney engines. In the case of Block 50’s (my particular favorite to fly), the % gauge is merely an indication of how much power you have over other variants with respect to pounds of thrust among them all. By contrast, the P&W F100-PW-220 engine is rated at 14,590 lbs of thrust (23,770 lbs with afterburner) & the GE’s F110-GE-100 is rated at 17,155 lbs (28,984 lbs with afterburner).
EDIT: Forgive me, I quoted Block 40 & 42 engines. Block 50 & 52 engines are… :nerd:
50: GE F110-GE-129 - rated the same as Block 40 F110-GE-100 engine,
52: PW F100-PW-229 - rated at 17,000 lbs of thrust (28,500 lbs with afterburner) -
AB state is clearly and easily visible on Noz Pos gauge and/or Fuel flow.
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100% is an RPM “datum” figure during design of the engine. Engineers pick it as a reference value so users can refer to % instead of actual RPM number. But life happens after figure is picked, they figure out they can run the engine at more or less than 100% due to improvements in design, new parts, different engines, new materials, or simply testing. Instead of redesignating what 100% is which could cause all sorts of confusion (wait, which %, % 1989 or % 2001?) the new functional RPM values are allowed to be different.
MiG-29 probably also has a rich history but if it’s not modeled in so much depth it’s just assumed 100% is mil thrust which is nominally true anyway.
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AB state is clearly and easily visible on Noz Pos gauge and/or Fuel flow.
…the former assuming your eyesight is good enough to read the tiny gauge in the 3d pit. At my age, this is not nearly so simple.
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Fuel Flow is your best and most direct indication.
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…the former assuming your eyesight is good enough to read the tiny gauge in the 3d pit. At my age, this is not nearly so simple.
If you can read the RPM you can see where the NozPos needle is pointing (no need to read the value, just need to see that the needle is not zero, means that engine is beyond Mil)
And as Stevie said, FF is also a big clue.
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Is the nozzle behavior the same across all blocks … and other planes (F-18 )? I thought there were some differences. (Maybe just with gear down…?)
I also have a hard time reading the FF gauge, depending on the lighting and visor etc… one of the hidden costs of flying high default FOV (100°) I suppose. But I can make out how many digits it’s displaying… lol
But the tactile sensation of pushing through a detent applies even when you’re looking back over your shoulder
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In the case of Block 50’s (my particular favorite to fly), the % gauge is merely an indication of how much power you have over other variants with respect to pounds of thrust among them all.
So basically you’re saying… “these go to 11”
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Is the nozzle behavior the same across all blocks … and other planes (F-18 )? I thought there were some differences. (Maybe just with gear down…?)
I also have a hard time reading the FF gauge, depending on the lighting and visor etc… one of the hidden costs of flying high default FOV (100°) I suppose. But I can make out how many digits it’s displaying… lol
But the tactile sensation of pushing through a detent applies even when you’re looking back over your shoulder
I used to work in AB Controls at GE on the F110 and F101, and I don’t know if the Pratt engines do this (or the F404, but I would expect they all do) but I know the GE engine nozzles pre-open past 100% and then choke down to ideal throat area once lit and the flow is established. That happens fast, but slow enough to observe…but if you are watching that, you aren’t flying.
The real indication that the process has even started is still the change in Fuel Flow; again, you don’t have to read the number, just note that the needle/number has spiked up from where it had been in getting to steady state. You can feel the acceleration once the light-off occurs - it’s not “violent” like you might think…but you can tell, as your body inertia lags the jet’s acceleration for a split second. I’ve had a chance to fly a RL Super Hornet in the Trainer config didn’t even notice the feel of the throttle detent - I was too busy paying attention to too many other things and I just muscled through it when I was told to accel to max - one might be more aware in a Viper because of having to lift/rotate the throttle. All depends on muscle memory and habit…I’d guess.
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…the former assuming your eyesight is good enough to read the tiny gauge in the 3d pit. At my age, this is not nearly so simple.
Yep, Concur. The FF on the Hornet is more readable, but down lower. That’s why I like a FF gauge on MFDE