[CHECKING] Turn Rate

[Prancingkiller]

since im not getting an answer on many different threads about that, maybe here's the correct place to get one, is that 20-22 °/s the correct sustained turn rate you intended to model the hornet with? ACMI LINK

track as attachment

 

condition

f18.trk

Edited October 10, 2019 by Prancingkiller

[GGTharos]

Add more details - exact aircraft configuration. Track is better than ACMI here as well.

[Prancingkiller]

track is there, i thought everything could be seen on track, that's it:

 

[GGTharos]

You're correct, I thought it was a tacview. Game track does indeed give all the required info.

[Vosene]

Open Source Reference Points for F/A18-C Sustained Turn Rate

 

There isn’t much open source data on F/A-18C E-M but there is an official US Government open source document with two reference points for sustained turn rate:

 

At sea level, the F/A-18C’s sustained turn rate is 19.2 degrees per second.

 

At 15,000 feet, the F/A-18C’s sustained turn rate is 12.3 degrees per second.

 

Configuration - Weapons load is 2 AIM-9 and 2 AIM-120 carried externally, no external fuel tanks and 60 percent fuel remaining.

 

While it doesn’t explicitly state it, I assume the sustained turn rate is derived using Standard Atmosphere as it is taken from official Navy data. They use U.S. Standard Day, 1962.

 

Source - U.S. General Accounting Office Report to Congressional Committees. Navy Aviation. F/A-18E/F will Provide Marginal Operational Improvement at High Cost. Dated June 1996. Page 30 of Report, page 32 of pdf.

 

Not sure if ED rules prevent linking. Shouldn’t do as this is an open source Government report not a Flight Manual but I’ll refrain from posting link just in case. It can easily be found with a quick Google search.

Edited October 10, 2019 by Vosene

[GGTharos]

It doesn't say which engine though, and doesn't say if the wings are clean. In any case, ED has certain documents so it would be nice of them to check.

[Prancingkiller]

There isn’t much open source data on F/A-18C E-M but there is an official US Government open source document with two reference points for sustained turn rate:

 

At sea level, the F/A-18C’s sustained turn rate is 19.2 degrees per second.

 

At 15,000 feet, the F/A-18C’s sustained turn rate is 12.3 degrees per second.

 

Configuration - Weapons load is 2 AIM-9 and 2 AIM-120 carried externally, no external fuel tanks and 60 percent fuel remaining.

 

While it doesn’t explicitly state it, I assume the sustained turn rate is derived using Standard Atmosphere as it is taken from official Navy data. They use U.S. Standard Day, 1962.

 

Source - U.S. General Accounting Office Report to Congressional Committees. Navy Aviation. F/A-18E/F will Provide Marginal Operational Improvement at High Cost. Dated June 1996. Page 30 of Report, page 32 of pdf.

 

Not sure if ED rules prevent linking. Shouldn’t do as this is an open source Government report not a Flight Manual but I’ll refrain from posting link just in case. It can easily be found with a quick Google search.

 

I found the doc, interesting one, can't see when it's written about the configuration:

 

Configuration - Weapons load is 2 AIM-9 and 2 AIM-120 carried externally, no external fuel tanks and 60 percent fuel remaining.

 

for the tests

[Vosene]

I found the doc, interesting one, can't see when it's written about the configuration:

 

Configuration - Weapons load is 2 AIM-9 and 2 AIM-120 carried externally, no external fuel tanks and 60 percent fuel remaining.

 

for the tests

 

It is in the footnote at the bottom of Page 30.

[Vosene]

Although not an official source, an interesting data point in this post from 2015:

https://forums.eagle.ru/showpost.php?p=2391689&postcount=385

 

States a sustained turn rate at 10,000ft of 13.2degrees/second. That config is 2 Sparrows (as opposed to 2 AIM-120 in the above config), 2 Sidewinders and 60% internal fuel, for a total gross weight of 33700lbs.

 

Post states that data is from A1-F18AC-NFM-210, so 402 engines, same as the F/A-18C in DCS.

[Vosene]

It doesn't say which engine though, and doesn't say if the wings are clean. In any case, ED has certain documents so it would be nice of them to check.

 

Agreed, you can work some of it out though. For example, DI=0 for F/A-18C (source is -200) includes 2x wingtip mounted AIM-9 so this is where they would be.

 

If ED have the reference data then hopefully they will confirm if there is an issue with sustained turn rate.

[Delta59R]

I would recommend any testing done to be performed in standard day temps (15c) just to keep consistency. Even in DCS, temperature affects performance, sometimes unrealistically. https://forums.eagle.ru/showthread.php?t=236407

Edited October 11, 2019 by Delta59R

[Prancingkiller]

devs are much interested in clarify our doubts as i can see

[NineLine]

I'll look into, thanks.

[Prancingkiller]

Any news about that?

[NineLine]

Nothing new right now, there aren't really any good graphs for this, so it requires more research to confirm if there is an issue. But the team will look into it.

[aaron886]

If there are no good data available with which to confirm current performance, how was the original model created? I sure hope something comes of this. Look at any video of an aggressive, sea level, aerobatic performance. You won't see a 360 degree turn under ~20 seconds and that's a slick jet. The DCS Hornet can pull off a 16 second turn.

 

 

[Sierra99]

The DCS Hornet can pull off a 16 second turn.

 

At what altitude?

 

At sea level, the F/A-18C’s sustained turn rate is 19.2 degrees per second

.

 

States a sustained turn rate at 10,000ft of 13.2degrees/second.

 

At 15,000 feet, the F/A-18C’s sustained turn rate is 12.3 degrees per second.

 

You have the test conditions from the report...is the DCS F-18 performance reasonable close?

[NineLine]

If there are no good data available with which to confirm current performance, how was the original model created? I sure hope something comes of this. Look at any video of an aggressive, sea level, aerobatic performance. You won't see a 360 degree turn under ~20 seconds and that's a slick jet. The DCS Hornet can pull off a 16 second turn.

 

 

 

There are no good graphs, but we don't use the graphs to build an FM, only to check it.

[Nomad]

If there are no good data available with which to confirm current performance, how was the original model created? I sure hope something comes of this. Look at any video of an aggressive, sea level, aerobatic performance. You won't see a 360 degree turn under ~20 seconds and that's a slick jet. The DCS Hornet can pull off a 16 second turn.

 

 

You forget that players in dcs pretty much never let go of the paddle switch, while in rl it's probably the opposite. You won't do a 16 sec sustained turn under normal dcs conditions without over-g'ing the aircraft.

[Prancingkiller]

There are no good graphs, but we don't use the graphs to build an FM, only to check it.

So no graph no check, i got it, well, after that i'll stop trying to understand how's the hornet winning rate fights against the viper

[Snappy]

You forget that players in dcs pretty much never let go of the paddle switch, while in rl it's probably the opposite. You won't do a 16 sec sustained turn under normal dcs conditions without over-g'ing the aircraft.

 

THAT behavior is something that should get fixed.Hilariously a not too small percentage of those players is probably at the same time jabbering constantly about maximum realism in various forms here in the forums, regarding g-tolerance,warm-up etc.

 

 

Really looking forward to ED implementing some sort of realistic airframe reaction to that constant over-g-ing , whether its wing snappoff, bent frame and degraded performance or whatever.

 

 

Snappy.

[borchi_2b]

Wings do not snap off from constant over g. first of all, they start to bend and twist a bit, which causes the plane to be constantly out of trim, so flying a straight line or level without controlling it to do so gets practically impossible and if the over g is close to wingbreak, laminar of the wing comes off first. After that a wingbreak might happen.

[Snappy]

I know that the wings don‘t snap off right away.Its one possible outcome though depending on the amount of over-g.However so far, no airframe reaction /deformation/ damage whatsoever is modelled, in response to the omni-present use of the switch which is making the whole thing kind of ridiculous in my opinion.

Especially in a simulation where no small part of the crowd is constantly waving

the super-realism banner around.

 

 

Regards,

 

 

Snappy

[GGTharos]

The result might be nothing at all - ie. the airframe handles it fine, but life expectancy is reduced ... and in a shooting match you're not going to worry about airframe hours. You can have reduced airframe hours or go to 0 hours right now because you didn't use the switch.

 

Really looking forward to ED implementing some sort of realistic airframe reaction to that constant over-g-ing , whether its wing snappoff, bent frame and degraded performance or whatever.

[Snappy]

The result might be nothing at all - ie. the airframe handles it fine, but life expectancy is reduced ... and in a shooting match you're not going to worry about airframe hours. You can have reduced airframe hours or go to 0 hours right now because you didn't use the switch.

 

 

Please don't bother GGTharos.

 

 

A) you don't know.

 

 

and

 

 

B) in a real shooting match a lot of things are different. If you want to argument that way you could only play DCS until you crash/get shot down in a fatal way for the first time.

 

 

 

Because theres no try again either in real life in the above cases.

But strangely enough,that's always something entirely different...right.

 

Never mind, I was simply trying to point out the inconsistencies in the mentality of " more more more realism and lets do everything according NATOPS " on the one hand and on the other hand happily downtaping the override switch.

 

 

Snappy

Edited October 29, 2019 by Snappy