PSA: F-14 Performance/FM Development Status + Guided Discussion

[SgtPappy]

27 minutes ago, Victory205 said:

Indeed, the quote system drives us all nuts.

Standard tanking speed was 250 knots using organic assets. The KC10 and 135 would typically be at 280 KIAS, while C130’s were at 220-230 usually. Engine stall in wake turbulence wasn’t an issue. It suddenly became a thing after “Top Gun the Movie™ “ was released in 1986. I remember that all of a sudden, my RIO was worried about it.

250 was a sweet spot, that’s what I set up the S3 at while testing drag and throttle response during tanking. It didn’t waste a lot of fuel, plenty of maneuver authority and engine response. You could move in and stop precisely without too much coast. I generally moved the wings aft a couple of clicks, which ended up being around 35 degrees. Whatever works for you. Moving the wings aft increases the deck angle and reduces pitch response slightly. All the way to Bomb is more appropriate to the faster speeds of the USAF tankers, it also extended glove vanes which made the aircraft a little pitchy at those subsonic speeds. I didn’t use Bomb mode.

Oh crap, I inadvertently mentioned Glove Vanes…

Looks like my jet is in top gun movie mode then because I get most of my stalls flying through wash in-game! 

I've been setting my missions to have 300 KIAS tankers.. looks like I need to slow them down.

Edited November 5, 2021 by SgtPappy

[Cab]

1 hour ago, Baz000 said:

I never heard of this Cooper fella but now I'm interested to learn about him, I take it he musta been like a USN version of a Boyd and his OODA loop. The only other Cooper I heard of is B.D. Cooper but they never found him or the money lol.

Google: jeff cooper modern technique of the pistol

Nothing to do with aviation but he was a Marine officer during WW2.

[Victory205]

1 minute ago, Cab said:

Google: jeff cooper modern technique of the pistol

Nothing to do with aviation but he was a Marine officer during WW2.

Modern Technique of the Pistol is a bit outdated. Like most in completion and law enforcement, I’m a mod iso shooter though, he was pretty dogmatic about the Weaver Stance. Rob Leatham, Brian Enos (the zen of shooting), Kelly McCann (integrated combatives) are probably better sources. Cooper is great on mindset, which applies to every facet of life.


@SgtPappy 

Stalls are overstated right now. One of the long discussions has involved reducing the stall issues from that of “conventional wisdom” (that dumb movie again). Eventually we’ll get less stalls due to wake turbulence, and inevitable dual stalls in flat spins in the A (and some in the B too).

 

[gnomechild]

38 minutes ago, Victory205 said:

Stalls are overstated right now. One of the long discussions has involved reducing the stall issues from that of “conventional wisdom” (that dumb movie again). Eventually we’ll get less stalls due to wake turbulence, and inevitable dual stalls in flat spins in the A (and some in the B too).

What do you think about the stall warnings flying through the trail of a lofting Phoenix? I always think it's pretty cool when that happens. I'm sure rocket exhaust is a lot hotter than jet engine, but I don't know if the volume is enough. It is a pretty big missile though. 

[lunaticfringe]

3 hours ago, Cab said:

I couldn't agree more. Plus, he knew how to turn a phrase to catch your attention.

In fact, I think it's time to go back and re-read his archived Gunsite Gossip newsletters just for fun.

As a quick aside, I would love/hate to hear his specific thoughts on what Thell Reed's daughter did/didn't do on a particular movie set recently. 

[LanceCriminal86]

24 minutes ago, Victory205 said:

Remember gang, “stuck on stupid” doesn’t imply a lack of mental facility, it means focused on the wrong thing, especially trivial items that aren’t germane to the real problem. Fiddling with the radio when you’re about to fly into a mountain. We all do it. 

If Hummingbird would just get his arse up to 5000 feet with 4x4 at the test weight (you do understand that the 6.5G limit is associated with a weight limit), he’d be a great asset. I think he’s afraid of heights.

The detuning thing continues to be obscure. The initial cadre in the 124 RAG and VF1 and 2 had massive issues with fan blades coming off and cutting fuel lines and cells. They were grounded from time to time until a containment could be designed and put around the engine casing to prevent it. Somewhere in that time frame, the engine thrust was reduced as an adjunct of changing fuel control behavior to prevent stalls. When or exactly what that entail was never articulated to us.

The difference between installed thrust, ram effect, mid compression bypass losses vs the absolute thrust delta remains somewhat murky. In the end, the pilot goes up and maneuvers to get a feel for what the aircraft will do, what works, and what doesn’t. The focus on determining precise thrust numbers that you see from enthusiasts wasn’t a thing. 

Just to reiterate. We had very few issues with engine stalls. I canvassed my squadron buds and the hours between stalls averaged ~1600 hrs per pilot. We learned how to manage the throttles. 

The GE engines were the real answer, and they had problems too.
 

@Victory205 This sounds a lot like discussing Ballistic Coefficients. You have people that understand the mechanics of how velocity impacts BC, and how atmospherics and inconsistencies of cartridge production and bullet production further cause changes to velocities and ballistic coefficients, and then how a rifle's interaction with said cartridge can change the velocity and thus the BC, and reasons why the numbers printed in manuals and box are basically useless. And then you have the folks that don't.

[Victory205]

13 minutes ago, LanceCriminal86 said:

@Victory205 This sounds a lot like discussing Ballistic Coefficients. You have people that understand the mechanics of how velocity impacts BC, and how atmospherics and inconsistencies of cartridge production and bullet production further cause changes to velocities and ballistic coefficients, and then how a rifle's interaction with said cartridge can change the velocity and thus the BC, and reasons why the numbers printed in manuals and box are basically useless. And then you have the folks that don't.

One word - Labradar

Wasn’t a Harrier pilot shot down in the Falkland by a SAM that he was visually tracking? Supposedly he didn’t bother to maneuver because he was above the “effective” range of the Argy SAMs?

59 minutes ago, gnomechild said:

What do you think about the stall warnings flying through the trail of a lofting Phoenix? I always think it's pretty cool when that happens. I'm sure rocket exhaust is a lot hotter than jet engine, but I don't know if the volume is enough. It is a pretty big missile though. 

Don’t know. In all of the missile shoots I heard about or was involved in, I never heard of an engine stall. Same with gun firing. I guess that the experience was different in the 1970’s.

[Hummingbird]

*sigh*

The sad part for me here is that I no point disagreed with the statement that performance charts aren't 100% true to life. That was never in contention, it's a pretty easy to grasp fact of life. Yet I've been made out, by certain individuals, to be in denial about this regardless, whilst what I actually write is being entirely (and feels like willfully) ignored. To then followingly be accused of instigating drama, and having to stand subject to various untactful comments and ad hominem attacks.. My only question is: Why? 

I understand perfectly well that these aircraft performance charts don't equal 100% reality. But like I also said, this goes for all aircraft, and regardless it's by far the best source we've got. Hence aiming to match these charts with the precision we're capable of, is/should be the goal. Why? Because then all aircraft are calibrated to the same standard = what the brightest minds and test pilots out there could deduce. 

I don't see that to be an unreasonable goal or expectation for a hardcore flight sim. 

Edited November 5, 2021 by Hummingbird

[LanceCriminal86]

30 minutes ago, Hummingbird said:

*sigh*

The sad part for me here is that I no point disagreed with the statement that performance charts aren't 100% true to life. That was never in contention, it's a pretty easy to grasp fact of life. Yet I've been made out, by certain individuals, to be in denial about this regardless, whilst what I actually write is being entirely (and feels like willfully) ignored. To then followingly be accused of instigating drama, and having to stand subject to various untactful comments and ad hominem attacks.. My only question is: Why? 

I understand perfectly well that these aircraft performance charts don't equal 100% reality. But like I also said, this goes for all aircraft, and regardless it's by far the best source we've got. Hence aiming to match these charts with the precision we're capable of, is/should be the goal. Why? Because then all aircraft are calibrated to the same standard = what the brightest minds and test pilots out there could deduce. 

I don't see that to be an unreasonable goal or expectation for a hardcore flight sim. 

 

But that's exactly the point that you state and then proceed to step right back around to wanting it to match/be accurate to the chart. It's acknowledged that the numbers for some areas of the FM are fudged (by the Navy themselves) because they didn't test at sea level, so why should that portion of the chart be considered a gold standard by which the DCS FM MUST conform?

[Hummingbird]

28 minutes ago, LanceCriminal86 said:

But that's exactly the point that you state and then proceed to step right back around to wanting it to match/be accurate to the chart. It's acknowledged that the numbers for some areas of the FM are fudged (by the Navy themselves) because they didn't test at sea level, so why should that portion of the chart be considered a gold standard by which the DCS FM MUST conform?

 

The performance at SL is obviously calculated, as it is for all fighter jets (testing maneuvering limits close to the floor is an absolute no go for pretty obvious reasons). That doesn't mean the estimated performance isn't accurate however (accurately calculating performance at lower alts based on flight tested performance higher up is something the industry pro's have been able to do for a long time now) and it doesn't mean it's 100% faultlessly accurate either.  But that's not the point. The point is, and this is important, it is THE most accurate data we're ever going to get, deduced (and most certainly NOT fudged) by the people best equipped to do so.

Thus why on earth not aim to match what is the most likely performance as pr. the true professionals? And do it across the board for every module, so that they're all calibrated to the same standard.

In my mind, it's the only logical path.

 

Anyway, I'm honestly getting tired of discussing this, as HB are obviously committed to getting it right (why else put so much effort in?), as they've said multiple times themselves, and I've been thanking them for it from the start. In short I'm not, and have not been, complaining. I've only shown test results and stated what can be expected. I've been a happy camper from the start, eagerly waiting the next update with further tweaks and an ever increasingly accurate FM. We're spoiled, and I feel priviliged to be living in a time where this is possible.

 

Over and out for now!

Edited November 5, 2021 by Hummingbird

[LanceCriminal86]

I get where you are coming from. I've been rivet counting visual issues to Victory205 and Cobra's chagrin, but after sitting down and actually looking at stuff I realized there will have to be some concessions somewhere. I'm not saying that's 100% the case here, but I get what Victory is trying to impart here.

It's a different topic, but there were some things I used to take as gospel that were/weren't done. Then within a few weeks time I saw each of them shattered by either direct photographs, documentation, or first-hand accounts. It definitely adjusted how I looked at government manuals and documents. Not that they weren't a great starting point, but just understanding that they often were flawed or lacked coverage of what happened to a system after its initial issue. Once that sank in I stopped thumping the TMs and OMs and started listening more to armorers and guys that actually fielded the equipment because many either demonstrated that it underperformed, or in some cases outperformed the posted data. And often I was able to verify their findings practically speaking.

[lunaticfringe]

2 hours ago, Hummingbird said:

The sad part for me here is that I no point disagreed with the statement that performance charts aren't 100% true to life. That was never in contention, it's a pretty easy to grasp fact of life. Yet I've been made out, by certain individuals, to be in denial about this regardless, whilst what I actually write is being entirely (and feels like willfully) ignored. To then followingly be accused of instigating drama...

When chasing 1.5 DPS and what amounts to rounding errors against the chart, that does legitimately begin to look like a push towards something other than helpfulness- especially after you (and everybody else) have been asked to stop by the two people working on the FM.  Instead, you lead with "I know they said don't, but...".   

They have better tools to do this process, and have noted specific areas they know are at issue that you haven't.  And still- you've ignored the people doing the heavy lifting after they asked, but you're uncomfortable with being ignored? 

That's a bit of a stretch- you have to admit.

2 hours ago, Hummingbird said:

I understand perfectly well that these aircraft performance charts don't equal 100% reality. But like I also said, this goes for all aircraft, and regardless it's by far the best source we've got. Hence aiming to match these charts with the precision we're capable of, is/should be the goal. Why? Because then all aircraft are calibrated to the same standard = what the brightest minds and test pilots out there could deduce.

See, here's an example- you acknowledge that paper charts aren't 1:1 exact, but then raise a question by inference as to whether or not the goal of the people doing the FM work to the highest standard is what they're actually after.  One of the reasons the aforementioned 3-5% variance is accepted in the professional realm against EM projections is based around the acknowledgement that the real time model is built to contend with far more than the ICAO standard day configuration- an environment that you'd be hard pressed to find a single example of taking place in actual flight test.  There's slop in the charts; if the engine, wing, and drag modelling is to a higher degree of precision in the real time simulation, where it breaks from those projections may well be more accurate than the charts you're pounding to, especially in those places where the human error of the draftsman or the need to apply "graphic design for effect" has been noted. 

 

Edited November 5, 2021 by lunaticfringe

[Hummingbird]

What I am refering to as being ignored are all the times I've said/done the exact opposite of what some of you are accusing me of saying/doing. I mean the easiest to spot example of this is Victory keeping on claiming I've done no tests at 5 kft, when it was infact one of the first things I did... and what did I comment following those tests? I gave credit, and then I moved on to focus on the altitudes where performance still didn't match. 

 

Also I know FC said that there's no point in testing right now because the FM is still being adjusted, he however didn't say "please don't test", which is very different, wouldn't you say? There's a clear distinction between those two things if you ask me. So I then did some tests just to document what performance is like right now (that way any changes, when they arrive, are visible), whilst at the same time acknowledging (not ignoring) what FC had already said, i.e. that current performance is not final, hence my figures are not to be taken as a complaint or criticism, but as documentation. I'm not out to hurt anyone here. Yet you're completely looking past all this and instead now trying to twist it into some sort of narrative where I'm feeling offended for being ignored in general? I mean come on now...

 

The facts (i.e. what is actually written) are being ignored, and a false narrative is created. That's what tires me, and hence I don't really see the point in continuing to explain myself when  I feel like Im seemingly being purposefully misconstrued.

 

So I'm going to go back to my testing and document it for everyone to see, both so that they get an idea of areas where they might expect improvement and so that changes become more visible. Also the script Dalan kindly provided me is proving quite useful in reducing the workload to achieve accurate figures, so I also wanted to show my results with this as promised.

 

TLDR; I don't claim the charts are 100% accurate, but they are the best we got and are ever going to get, and thus matching them as precisely as possible, human error, slop and graphic artistic fudges and all, should be striven for... same as for all the other modules. That way you got your back covered when someone goes "I don't believe this performance is accurate" or "this a/c is over/underperforming". And that's essentially what it's about, matching the most accurate data we have access to, warts and all, because then you cannot do it any better.   

 

Edited November 5, 2021 by Hummingbird

[Victory205]

The wounded victim look is unbecoming.

When the time comes, simply produce a paper with the targets and outcomes, using the correct charts in known configurations and altitudes, no additional extrapolation for any reason, including either video or confirmation from the community that replicates your results. Not some half assed snippet that lists rows of numbers. If your numbers don’t correlate, then you need to provide proof. That’s how peer review is done.

When you reference irrelevant charts, like the SAC and HM, or don’t produce both testing methodology in terms of how and where you obtained both the targets and the results that don’t correlate at least via video, you lose credibility. 

To avoid bias, most fly the test, then look up the targets after the test is complete.

Do it right, or don’t do it at all. 

[lunaticfringe]

29 minutes ago, Hummingbird said:

Also I know FC said that there's no point in testing right now because the FM is still being adjusted, he however didn't say "please don't test", which is very different, wouldn't you say? There's a clear distinction between those two things if you ask me.

Did you understand his inference then?  Because you seemed to earlier in the week.  

This isn't a false narrative.

 

[Hummingbird]

18 minutes ago, lunaticfringe said:

Did you understand his inference then?  Because you seemed to earlier in the week.  

This isn't a false narrative.

 

 

Why are you qouting me? Quote FC, he's the one who said it:

 

 

No "please don't test" there, just a "no reason to be testing now", as I said.

 

Hence why I acknowledged this when posting the data, to show that I was aware the performance was still being tuned, and hence highlight I wasn't complaining, unlike how you wish to portray it for some reason.

Edited November 5, 2021 by Hummingbird

[eatthis]

On 11/4/2021 at 9:17 PM, Victory205 said:

Think in terms of total energy. Don’t get bogged down in thrust to weight. We’re not adding power in the zoom.

Simple concept, too many are rushing down rabbit holes.

i get the distinct impression im being a bloody idiot here but im still not getting it lol.
how does the weight difference effect the total energy? 

23 hours ago, Baz000 said:

 

well, he was talking about a Vulcan bomber vs. a F-16 in a climb... I thought i'd provide some answer to him i'm guessing he must be a Brit if he randomly throws out the Vulcan bomber out there

vs. this

oh, he said "full chat" that was a dead give away to me that he must also be a Brit too.

 

yeh im a brit, i picked the vulcan because its just a fantastic machine

[Hummingbird]

30 minutes ago, Victory205 said:

The wounded victim look is unbecoming.

When the time comes, simply produce a paper with the targets and outcomes, using the correct charts in known configurations and altitudes, no additional extrapolation for any reason, including either video or confirmation from the community that replicates your results. Not some half assed snippet that lists rows of numbers. If your numbers don’t correlate, then you need to provide proof. That’s how peer review is done.

When you reference irrelevant charts, like the SAC and HM, or don’t produce both testing methodology in terms of how and where you obtained both the targets and the results that don’t correlate at least via video, you lose credibility. 

To avoid bias, most fly the test, then look up the targets after the test is complete.

Do it right, or don’t do it at all. 

 

I'm not writing a scientific paper. I am providing my test data for all to see, and I ofcourse have target speeds to test at, esp. at SL where there are only four reference points. If you believe I am making up my results, then run the tests yourself, Dala can provide you the script. You'll get the same results in terms of STR. 

Also not sure why you keep rejecting the specific excess power chart (or HM if you prefer), if you wanna know wether it's accurate all you have to do is cross reference it with the load factor & doghouse plots and you'll see the 3 G, 5 G & 6.5 G Ps charts match them precisely at every altitude. So I see no valid reason not to trust them.

Edited November 5, 2021 by Hummingbird

[lunaticfringe]

14 minutes ago, Hummingbird said:

 

Why are you qouting me?

Because you admitted something different then versus what you're choosing not to acknowledge now, as some form of justification for placing your limited testing of the changes here.  You realized what was being inferred, you just don't like it- even when you're challenged to admit to having said it, because you just want a reason to keep on going.

At the end of the day, Creason and Victory have both also outlined, explicitly, what they expect to see for continued focal point discussion, which you've failed to provide since.  You can't provide that, so you've migrated to call it "documentation" of the changes, but it's not.  For them, it's noise.  It's not helping anything, and has simply caused a bunch of nonsense. 

If you're not going to show validation or critique out to the standard they've requested, stash it somewhere else- for your sake as much as anyone else.  

Edited November 5, 2021 by lunaticfringe

[Hummingbird]

12 minutes ago, lunaticfringe said:

Because you admitted something different then versus what you're choosing not to acknowledge now, as some form of justification for placing your limited testing of the changes here.  You realized what was being inferred, you just don't like it- even when you challenged to admit to having said it, because you just want a reason to keep on going.

At the end of the day, Creason and Victory have both also outlined, explicitly, what they expect to see for continued focal point discussion, which you've failed to provide since.  You can't provide that, so you've migrated to call it "documentation" of the changes, but it's not.  For them, it's noise.  It's not helping anything, and has simply caused a bunch of nonsense. 

If you're not going to show validation or critique out to the standard they've requested, stash it somewhere else- for your sake as much as anyone else.  

 

Admitted?! You're really going to make it sound like I was trying to stir up drama? That I had evil intentions posting those numbers? For real?

 

I quite litterally simply acknowledged he had advised there was no point in testing right now, so as to make it clear I wasn't posting a complaint or criticism, end of story. 

 

Jesus... this is fast turning into a witch hunt.

Edited November 5, 2021 by Hummingbird

[captain_dalan]

Please people, no need to draw daggers over this... 

Now i dream of a day when DCS will provide a platform that will allow for fatigue simulation and cumulative hours, a day of variation in AC of the same type performance that will make some of them so called "hangar queens" and other "hotrods". But it is not this day..... 

In the meantime, just to increase the sample size...... things AREN'T that bad. I mean, i wasn't gonna do more test until the next months patch, but if we want to be that pedantic...

mach 0.461 or 305 knots, 4.91 g
mach 0.47 or  311 knots, 5.10 g

So 0.1g or less difference at 304 knots or the plane doesn't sustain 5g at 304 knots, but at 307-308..... a 4 knot difference. If you want to fight over it ok, but i think we should let the update take place first and test the flight model later. 

EDIT: not to mention the A seems right on the money, well bellow 0.1g variance up to mach 0.8. 

Edited November 5, 2021 by captain_dalan

[Hummingbird]

I'll post a video of me doing the tests tomorrow, and then add the log file. I have no clue how you're reaching over 17 dps at M 0.46, here's another log file from me using your mission:

Can't breach 4.7 G @ M 0.46 no matter how hard I try. I wouldn't be bothered with 0.1 G either, but as you can see I'm getting 0.3 G less.

 

PS: I'm noticing a lot of alt & speed variance between your attempts, are you sure it's not logging attempts whilst alt is decreasing? From 16.4 dps average to 17.8 dps average is a huge difference, way beyond what should be possible.

 

PPS: I run the mission in "summer, clear sky, no wind" and 15 Celcius. Are you possibly running it in winter?

 

PPPS: Noticed the F-14A's slats/flaps oddly don't deploy below 350 kts, but on the B everything is fine.

Edited November 6, 2021 by Hummingbird

[flybull]

8 hours ago, Victory205 said:

Indeed, the quote system drives us all nuts.

Standard tanking speed was 250 knots using organic assets. The KC10 and 135 would typically be at 280 KIAS, while C130’s were at 220-230 usually. Engine stall in wake turbulence wasn’t an issue. It suddenly became a thing after “Top Gun the Movie™ “ was released in 1986. I remember that all of a sudden, my RIO was worried about it.

250 was a sweet spot, that’s what I set up the S3 at while testing drag and throttle response during tanking. It didn’t waste a lot of fuel, plenty of maneuver authority and engine response. You could move in and stop precisely without too much coast. I generally moved the wings aft a couple of clicks, which ended up being around 35 degrees. Whatever works for you. Moving the wings aft increases the deck angle and reduces pitch response slightly. All the way to Bomb is more appropriate to the faster speeds of the USAF tankers, it also extended glove vanes which made the aircraft a little pitchy at those subsonic speeds. I didn’t use Bomb mode.

Oh crap, I inadvertently mentioned Glove Vanes…

Glove Vanes Confirmed!.  "2 more weeks".

[Hummingbird]

@captain_dalan I now think I know how you got the results you did, it turns out the script WILL actually log a rate whilst you're losing alt, so not true Ps=0 . You can see it in the video below where I use your mission, notice that during some of the script's recordings altitude is actually decreasing as the script logs the rate. 

 

I also once again manage to get the aircraft very stable at M 0.46, and get a good long stream grabs starting at 03:14 min. Also note the infobar and the G reading it is registering = 4.6-4.7 G throughout:

 

And the logfile with the recordings so you can compare with the video:

So according to the script an average of 16.8 dps @ M 0.46 =  4.75 G.  Whilst the actual infobar reads 4.6-4.7 G throughout that turn.

 

Compare this with my last result (it's the same):

Quote

Different set of figures for sea level @ M 0.46 (304 KTAS) target speed using the script kindly provided by Cpt.Dalan:

 

F-14B, 55,620 lbs, 4xAIM9 + 4xAIM7, Std. day 15 C, unlimited fuel:

SCRIPTING: TR: Counter, Alt(m), GS(km/h), GS(Mach), Turn Rate(deg/s)

2021-11-04 22:54:09.060 INFO    SCRIPTING: TR: 3 /  23 / 562 / 0.460 / 16.9 = 4.80 G  
2021-11-04 22:54:14.264 INFO    SCRIPTING: TR: 4  / 28 / 560 / 0.457 / 16.9 = 4.78 G
2021-11-04 22:54:42.550 INFO    SCRIPTING: TR: 5  / 36 / 563 / 0.460 / 16.8 = 4.78 G
2021-11-04 22:54:47.752 INFO    SCRIPTING: TR: 6  / 44 / 563 / 0.460 / 16.6 = 4.72 G
2021-11-04 22:54:52.958 INFO    SCRIPTING: TR: 7  / 40 / 565 / 0.462 / 16.8 = 4.79 G

 

 

Edited November 6, 2021 by Hummingbird

[Hummingbird]

I hope this suffices for a "peer review"