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JRM

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Did more itr tests with the scripted mission and I put it over a public nasa f-18 em chart  and  a tr vs bleed-rate graph (green=nasa, blue=dcs).

Itr: Lift limit line looks quite good but is slightly left.  Max itr looks good too, speed bleed at corner is quite a bit too low (but so is aoa (~25°) @ m0.65) but good below m0.45.

Str : mstr is perfect.  Str is slightly low between m0.5 and 0.7 and slightly high above m0.85.

I would say, good work so far..

https://ntrs.nasa.gov/citations/19950007836

D5DDAD83-384A-4D05-BF8D-9867C1F51D97.jpeg

FFCDCEE5-5C69-4A0C-AE5D-EFC85F55B48A.jpeg

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1 hour ago, Figaro9 said:

Did more itr tests with the scripted mission and I put it over a public nasa f-18 em chart  and  a tr vs bleed-rate graph (green=nasa, blue=dcs).

Itr: Lift limit line looks quite good but is slightly left.  Max itr looks good too, speed bleed at corner is quite a bit too low (but so is aoa (~25°) @ m0.65) but good below m0.45.

Str : mstr is perfect.  Str is slightly low between m0.5 and 0.7 and slightly high above m0.85.

I would say, good work so far..

https://ntrs.nasa.gov/citations/19950007836

D5DDAD83-384A-4D05-BF8D-9867C1F51D97.jpeg

FFCDCEE5-5C69-4A0C-AE5D-EFC85F55B48A.jpeg

Great stuff, thanks for posting that! 

 

Could you please confirm, which G lines represent which G values on your chart? 

The source document shows a 7,33 G limit on the chart, in DCS I get 7,5 G at M 0,6, but on your chart it seems like max ITR happens at a lower G and also the DCS line is at a lower G over the corner speed.

For me in the same config corner is M0.6 AoA=30 at 7.5 G (DCS)

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At 33700 lbs (2x9 2x7) I have this for max ITR:

M= 0,60

AoA= 30

N= 7,5

EM_15000_DCS_F_18_vs_nasa_doc_15000k.jpg

F-18ITR_M0.6_15k.png

I used the weight on your chart, 33700 lbs.

I did not see the weight in the nasa doc. Maybe it is a bit heavier (7.33 limit G?)

 

EDIT: just checked, G limit is 7,3 at 34000lbs, so difference is marginal.


Edited by HWasp
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On 12/14/2021 at 9:42 AM, wilbur81 said:

Based on?

09:19

these guys. Something is wrong and ED are convinced the Viper numbers are spot on. But Movers statements says otherwise. Any how something isn’t right between the two.


Edited by Blinky.ben
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For me, as you can see, there is consistently a close to +1 G advantage on the lift limit line for the DCS Hornet vs the Nasa doc chart.

This is consistent with the HUD footage.

STR does seem to be correct for me as well up at 15000 feet in this config.

Again, I tested at 34000 lbs G limit is 7,3G.  NASA doc G limit is 7,33 so that config cannot be much heavier.

 

Could you please check your testing data again please?

39 minutes ago, Blinky.ben said:

09:19

these guys. Something is wrong and ED are convinced the Viper numbers are spot on. Something is wrong

 

I'm quite sure that Viper numbers are spot on, as they say. When I checked it last time STR was perfectly lined up to the HAF manual EM chart. 


Edited by HWasp
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those rates in the graph are the rates I get.

I do not use the info bar but the attached scripted missions. The turn rates are scripted into the dcs logs. So is sep, aoa ect.

 

At 33693 FCS does limit g to 7.3g max  according the fcs page in the pit. 7.5 g like displayed in the info bar according yout pic is not possible. So there might be a difference between fcs g-meter and the gz displayed in the info bar. Therfore ist probably better to use the attached mission (Standard day), cause turn rates are measured in game and you do not have to do math via g-loadings...

 

Sustained turn rate test flight f18.miz instantaneous turn rate test flight f18.miz

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12 minutes ago, Figaro9 said:

those rates in the graph are the rates I get.

I do not use the info bar but the attached scripted missions. The turn rates are scripted into the dcs logs. So is sep, aoa ect.

 

At 33693 FCS does limit g to 7.3g max  according the fcs page in the pit. 7.5 g like displayed in the info bar according yout pic is not possible. So there might be a difference between fcs g-meter and the gz displayed in the info bar. Therfore ist probably better to use the attached mission (Standard day), cause turn rates are measured in game and you do not have to do math via g-loadings...

 

Sustained turn rate test flight f18.miz 73 kB · 0 downloads instantaneous turn rate test flight f18.miz 351.57 kB · 0 downloads

Thanks, I'll check that.

Could you please tell me, on your chart, which G lines represent which G value?

It seems in your chart DCS hornet tops out at 7 G. Am I reading that correctly? If so, why is that?

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37 minutes ago, Figaro9 said:

those rates in the graph are the rates I get.

I do not use the info bar but the attached scripted missions. The turn rates are scripted into the dcs logs. So is sep, aoa ect.

 

At 33693 FCS does limit g to 7.3g max  according the fcs page in the pit. 7.5 g like displayed in the info bar according yout pic is not possible. So there might be a difference between fcs g-meter and the gz displayed in the info bar. Therfore ist probably better to use the attached mission (Standard day), cause turn rates are measured in game and you do not have to do math via g-loadings...

 

Sustained turn rate test flight f18.miz 73 kB · 1 download instantaneous turn rate test flight f18.miz 351.57 kB · 2 downloads

Sorry, but why are you so sure, that a slight G overshoot cannot occur? The FCS is not perfect. I would not disregard the infobar only based on that...

Is there any test / source / thread saying, that the infobar Gz is incorrect? I have never heard of that.

I did not see Gz values in the data dump, only longitudinal acceleration.

 

DCS dump.jpg

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I searched the forums regarding the infobar accuracy, and the only problem I have found, is regarding TAS and IAS. In case of TAS wind messes up the readout, it's a known bug.

But in my tests wind = 0, so that is a non-issue. I did not use the IAS readout on the infobar.

I have not found anything against the infobar G readout's accuracy.

I don't think, that the script calculated turn rate should take priority against ingame infobar G value, unless there is proof, that it is bugged.

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1 hour ago, Versor said:

Just want to add some picture. I was watching again Canadian Hornets and I noticed something that I hadn't noticed never before.

Canadian Hornets — PS-line.png

Good noticing that.  But how do we know that's specifically an F18c?  They could be discussing adversaries or a hypothetical platform.  Did they actually say in the video that this was for the hornet?

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@bkthunder

Sure, there's a way to stop ground crew from mounting the empty wing pylons on the eagle. 

1- Select the "empty" loadout and let ground crew finish rearming (no wing pylons should be mounted when using that loadout profile)

2- Once they're done, open the rearming window again, add 4 missiles on the "cheek" stations and accept (you can add a centerline fuel tank if you want too)

3- When the ground crew has loaded the third missile, execute the engine start command (the one that starts both engines in sequence, not the individual engine start commands)

4- After that, the fourth missile will be loaded and you'll get the "unable to comply" message from the ground crew, preventing the empty wing pylons from being mounted

5- Enjoy your minimun drag, mach 2+ capable eagle with 4 missiles


Edited by Hardcard
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@bkthunder

Sure, there's a way to stop ground crew from mounting the empty wing pylons on the eagle. 

1- Select the "empty" loadout and let ground crew finish rearming (no wing pylons should be mounted when using that loadout profile)
2- Once they're done, open the rearming window again, add 4 missiles on the "cheek" stations and accept (you can add a centerline fuel tank if you want too)
3- When the ground crew has loaded the third missile, execute the engine start command (the one that starts both engines in sequence, not the individual engine start commands)
4- After that, the fourth missile will be loaded and you'll get the "unable to comply" message from the ground crew, preventing the empty wing pylons from being mounted
5- Enjoy your minimun drag, mach 2+ capable eagle with 4 missiles
Last tried empty still put on the pylons. Was going to make a report for it.

Mobius708

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@Hulkbust44

I was going to request the option to remove pylons, just like we have it in the hornet.   

 

@bkthunder

I've noticed that the eagle's speed indicator (on HUD, at least) doesn't agree with the hornet's, which shows higher speed values for the same mach number. 
The eagle's mach meter seems to be giving relatively accurate indications, though, judging by TAS.

Anyway, in straight flight @ 50% fuel, pylonless eagle accelerates faster and reaches higher TAS than pylonless hornet (except at 10k ft, where the eagle hits a wall @ mach 1.27, but the hornet keeps going a little further). 

Sure, @ 50% fuel, eagle still has higher T/W than hornet, but that's how it's supposed to be, with those 💪 engines. 
Giving the hornet minimal fuel just so it can have the same T/W as the eagle isn't representative of practical situations. I don't fight eagles when I'm past bingo 😅.    

Besides, seems to me that the smaller hornet should generate less drag, so given the same T/W, I'd expect it to accelerate and climb faster... but the thing is that, in practical situations, it almost always has inferior T/W. 

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Watch Fights for Honor. Real pilot talks something about paddle switch and 10 G in Hornet. They talks about Viper accelaration. A few realy good information about current situation. But i don't know why people from ED they don't want to hear what a real pilot have to say. Or maybe they hear but they don't know how to do this.

 

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Speaking from experience doesn't translate directly to hard, empirical data. While the opinions and experiences from SMEs are definitely valuable, it's better as validation rather than direct implementation.

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On 12/18/2021 at 5:32 AM, Versor said:

Just want to add some picture. I was watching again Canadian Hornets and I noticed something that I hadn't noticed never before.

Canadian Hornets — PS-line.png

its a F18A chart and is the same as the VFA125 chart shown here from the thread "EM charts" also shown below below.

 

Fan18.jpg

 


Edited by IvanK
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On 12/18/2021 at 9:39 PM, Versor said:

Watch Fights for Honor. Real pilot talks something about paddle switch and 10 G in Hornet. They talks about Viper accelaration. A few realy good information about current situation. But i don't know why people from ED they don't want to hear what a real pilot have to say. Or maybe they hear but they don't know how to do this.

 

I watched Fights for Honor and listening to real pilots I realized how much the flight models F-18 and F-16 are in the WIP phase. It was sorry to hear Mover laughing at the overloads of a Hornet flying over 10G. For a while, ED improved the overuse of the paddle switch in the F-18, but that doesn't work again and players in dogfight keep abusing it, making the fight unrealistic. The conclusions were that the Hornet is very overpower and the Viper is well below its true performance. It remains to be patiently waiting for the FM corrections and the exit of both models from the WIP phase.

i7-8700K, Z370, 32GB DDR4-3000MHz, RTX 2080 Ti, FSSB R3L, TM Warthog HOTAS, CH Pro pedals, 2x MFD's, Windows 10 Pro, HP Reverb

 

DCS: F-16C, F/A-18C, F-14B, F-15C, AV-8B, M2000C, F-5E, A-10C, AJS-37, Su-27, Su-33, MiG-21bis, MiG-29, Spitfire LF Mk. IX, Bf 109 K-4, SA342, UH-1H

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I must say that comment and laugh with respect to the Hornet made me cringe as well.  Perhaps they will create a toggle for servers to turn off the paddle switch.

[sIGPIC][/sIGPIC]

i7 10700K OC 5.1GHZ / 500GB SSD & 1TB M:2 & 4TB HDD / MSI Gaming MB / GTX 1080 / 32GB RAM / Win 10 / TrackIR 4 Pro / CH Pedals / TM Warthog

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My result figures are close to @Figaro9 (sorry to have taken so long to do those tests mate, RL was just too hectic). Before i post them, just a few disclaimers i think we should all be aware about:
0. The NASA chart is ONLY for 15000ft, so just because the data may match the sample, we have no idea of how the jet performs comparatively in other parts of the envelope;
1. The NASA document doesn't state the configuration. It's pure coincidence that 2xSparrows - belly mounted, 2XSidewinders and roughly 65% fuel that equals 33693pds gross weight, seems to fit the chart best. In the words of Mr. Spock, "we happen to have a theory (i would say hypothesis) that happens to fit the facts available;
2. The configuration observed is with stores, albeit the most conformal stores possible. Still, ED is in the process of changing-refining the store drags, so any current tests may not match the final results;
3. Finally, these tests are best performed with larger statistical samples, so random variations and oscillations in the data points can be averaged out. Also, the best precision (possible within 0.1 metric unit) should be observed. 

But enough academics, these are my findings:
- The current FM with the above configuration in mind, happens to fit the NASA chart closely in the subsonic region up to mach 0.9 - there seems to be a slight dip in performance around mach 0.6, but this is a 4% variation, that is, inside DCS's standards as they are. Possible room for fine tweaks though;
- The extreme low speed part of the envelope can't really be evaluated with this tests - bellow mach 0.3, the plane is essentially stalling and so any data gathered is extremely erratic;
- The supersonic part of the envelope is overmodelled, that is, the jet has quite a bit more power then the chart predicts. This actually goes to confirm some user tests that claim the clean jet is capable of "supercruise" around this altitude. Further tests needed to confirm or deny this;

What i would like to see is more people doing these tests, with at least a dozen or passes for each data point, so we can eliminate statistical errors.
Have a good night guys, it's late here. And keep testing, i'll lurk even when i can't test or post!  

P.S. (edit) the small red dots-crosses are my results overlaid on the chart

Hornet flight model.jpg


Edited by captain_dalan
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Modules: FC3, Mirage 2000C, Harrier AV-8B NA, F-5, AJS-37 Viggen, F-14B, F-14A, Combined Arms, F/A-18C, F-16C, MiG-19P, F-86, MiG-15, FW-190A, Spitfire Mk IX, UH-1 Huey, Su-25, P-51PD, Caucasus map, Nevada map, Persian Gulf map, Marianas map, Syria Map, Super Carrier, Sinai map, Mosquito, P-51, AH-64 Apache

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My result figures are close to @Figaro9 (sorry to have taken so long to do those tests mate, RL was just too hectic). Before i post them, just a few disclaimers i think we should all be aware about:
0. The NASA chart is ONLY for 15000ft, so just because the data may match the sample, we have no idea of how the jet performs comparatively in other parts of the envelope;
1. The NASA document doesn't state the configuration. It's pure coincidence that 2xSparrows - belly mounted, 2XSidewinders and roughly 65% fuel that equals 33693pds gross weight, seems to fit the chart best. In the words of Mr. Spock, "we happen to have a theory (i would say hypothesis) that happens to fit the facts available;
2. The configuration observed is with stores, albeit the most conformal stores possible. Still, ED is in the process of changing-refining the store drags, so any current tests may not match the final results;
3. Finally, these tests are best performed with larger statistical samples, so random variations and oscillations in the data points can be averaged out. Also, the best precision (possible within 0.1 metric unit) should be observed. 

But enough academics, these are my findings:
- The current FM with the above configuration in mind, happens to fit the NASA chart closely in the subsonic region up to mach 0.9 - there seems to be a slight dip in performance around mach 0.6, but this is a 4% variation, that is, inside DCS's standards as they are. Possible room for fine tweaks though;
- The extreme low speed part of the envelope can't really be evaluated with this tests - bellow mach 0.3, the plane is essentially stalling and so any data gathered is extremely erratic;
- The supersonic part of the envelope is overmodelled, that is, the jet has quite a bit more power then the chart predicts. This actually goes to confirm some user tests that claim the clean jet is capable of "supercruise" around this altitude. Further tests needed to confirm or deny this;

What i would like to see is more people doing these tests, with at least a dozen or passes for each data point, so we can eliminate statistical errors.
Have a good night guys, it's late here. And keep testing, i'll lurk even when i can't test or post!  

P.S. (edit) the small red dots-crosses are my results overlaid on the chart
303158051_Hornetflightmodel.thumb.jpg.11f047b9c4c0d8eaa778cdc52b5cd3fa.jpg
Which document? Does it specify the engine type?

Mobius708

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9 minutes ago, Hulkbust44 said:

Which document? Does it specify the engine type?

Mobius708
 

The document was referenced before in the discussion i think, and linked here directly from NASA's site. The engines are the (then) new F404's. 

Modules: FC3, Mirage 2000C, Harrier AV-8B NA, F-5, AJS-37 Viggen, F-14B, F-14A, Combined Arms, F/A-18C, F-16C, MiG-19P, F-86, MiG-15, FW-190A, Spitfire Mk IX, UH-1 Huey, Su-25, P-51PD, Caucasus map, Nevada map, Persian Gulf map, Marianas map, Syria Map, Super Carrier, Sinai map, Mosquito, P-51, AH-64 Apache

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