F/A-18 vs F-16 Turn rate?

[SpaceMonkey037]

3 minutes ago, Noctrach said:

Alright, then how is my original information incorrect? he was way low on speed. And why are you looking at 15k charts either way? He was at 1-5 k feet in the pictures, and so you should base your data on that. Best turn rate speed at 5k is 475. You've mentioned that nowhere. Simply put, there is no flat spots for the GE-129 engine, the best turn rate is a fixed speed, and that speed is mostly based on the speed you're able to sustain without blacking out. For that reason the "thumb rule" for turn rate should be: Sustained as fast as possible under 500 knots without blacking out. Keyword: blacking out. Most of the time if you're on the limit you will black out, and so you will have to reduce your speed.

[Dee-Jay]

Hi Noctrach & Spacemokey!

 

Be careful, I been prosecuted and punished by moderation (and they were right as it is per rules) for having displayed on the forum a VERY common hydraulic scheme that we can find in a matter of a second on the Web ... so, a capture coming directly form the T.O. GR1F-16CJ-1-1 ... mmm ... I do not think it will be accepted (or ... I would not understand).

 

Kind regards.

Edited April 10, 2021 by Dee-Jay

[SpaceMonkey037]

1 minute ago, Dee-Jay said:

Hi Spacemokey!

 

Be careful, I been prosecuted by moderation (and they were right as it is per rules) for having displayed a VERY common hydraulic scheme that we can find in a matter of a second on the Web ... so, a capture coming directly form the T.O. GR1F-16CJ-1-1 ... mmm ... I do not think it will be accepted (or ... I would not understand).

 

Kind regards.

 

No no. I have never used the manual for this. I was looking at an F-16 doing a max AB sustained turn overhead and I used video analysis to figure out its speed. Nothing to see here go on with your day. 

[Dee-Jay]

I noticed after that post was from Noctrach ... but I am referring to your quote also. ... (Post edited accordingly)

 

Have a nice day gents!

[SpaceMonkey037]

5 minutes ago, SpaceMonkey037 said:

No no. I have never used the manual for this. I was looking at an F-16 doing a max AB sustained turn overhead and I used video analysis to figure out its speed. Nothing to see here go on with your day. 

No information was given in that picture other than where the information is from, but I agree, not a good idea to take pictures from those manual. Kinda hard to quote someone who only posted a picture of the manual while avoiding quoting the picture from the manual. O well.

[Noctrach]

44 minutes ago, Dee-Jay said:

Hi Noctrach & Spacemokey!

 

Be careful, I been prosecuted and punished by moderation (and they were right as it is per rules) for having displayed on the forum a VERY common hydraulic scheme that we can find in a matter of a second on the Web ... so, a capture coming directly form the T.O. GR1F-16CJ-1-1 ... mmm ... I do not think it will be accepted (or ... I would not understand).

 

Kind regards.

 

Noted, thanks for the heads up I figured a header wouldn't matter but I'll remove it

[Xavven]

I can find two different sea-level F-16 EM diagrams on a google search (heading of GR1F-16CJ-1-1 and T.O. 1F-16C-1-1). Depending on which one you look at, corner speed is either 0.55 mach or 0.50 (so 330-360 IAS), and Ps = 0 peaks at either 0.78 mach or 0.66 (so 440-520 IAS) right at the 9G line. The slope of the Ps = 0 line is about 0.5 deg./sec. for every 0.1 mach increase in speed until the 9G limit is reached, at which point there's an abrupt negative slope.

 

Sadly, I don't have access to a big array of EM diagrams in a manual that lets me choose the weight, altitude, engine, and drag index I want for any situation, but knowing the general range of these numbers for a few different altitudes is good enough IMO, as there are so many other variables factoring into what kind of turn at what speed you should be doing.

 

I could have bad information, of course, but until someone can get me something better, this is where I'm at. And it might be illegal to share anything anyway.

 

I will say, though, that if the fight starts 2-circle from a neutral pass, even 1 deg./sec. of extra turn rate is something I'll take by flying best STR instead or corner speed, even if it means I'm at the G-limit.

Edited April 10, 2021 by Xavven

[oldtimesake]

If you want  to do 2 circle in F-16, I suggest doing it above 10000 feet.

 

The peak STR in F-16 is achieved at relatively high speed at high G and you go black out easily in current DCS high g mechanics. There is no planned fix for that.

 

Above 10000 feet there is less chance of going black out and with 6 amraams on board you can still sustain more than 14.2 deg / sec in an F-16 at mach 0.85. Try other jets in similar loadout it is hard to sustain even 13.7 deg / sec.

 

If the enemy tries to go down and lure you do the same thing, don't take the bait. Stay above 10000 feet and wait for sufficient lateral separation, cash in some energy for angle. 

 

I leaned it the hard way. F-18, JF-17 and F-14 all have trailing edge flaps deployed automatically in high g turns, which helps them to turn tighter at lower speed. F-15/16's FCS don't do that. If you do it manually you need a multi-threading brain and I don't recommend that.

Edited April 11, 2021 by oldtimesake

[Snappy]

It will be very interesting to see what changes to the Hornet FM will result from its announced complete FM review.

However I wouldn’t expect too much, actually I wouldn’t  be surprised at all if it got even stronger.

Not that this would be realistic , when even its current FM seems overpowered or underdraggy in regards to 

sustained turn rate & vertical capabilities.

 

But unfortunately contrary to the F-16 theres a lot less data available for the Hornet variant to check against, except for that GAO report, which I wouldn’t consider sufficient or objective, so its up to ED and their interpretation of the data they have.

 

Regards

 

Snappy 

Edited April 10, 2021 by Snappy

[darkman222]

Yes thats my feeling too. In the F16 you have just one good turn and then it takes ages to get energy back.

Although this is an F16 thread here and I am not very used to the F15, but it seems that even in the F15 you'd struggle to outrate the F18 which again stresses that the turn rate of the F18 is too optimistic.

At least when I fly the F18 on a dogfight server its just about to accelerate to 360 kts pull the exact amount of G to stay at that speed and now just wait and outrate the opponent most of the time. The F18 can do that 360 kts turn forever.

[Noctrach]

1 hour ago, darkman222 said:

Yes thats my feeling too. In the F16 you have just one good turn and then it takes ages to get energy back.

Although this is an F16 thread here and I am not very used to the F15, but it seems that even in the F15 you'd struggle to outrate the F18 which again stresses that the turn rate of the F18 is too optimistic.

At least when I fly the F18 on a dogfight server its just about to accelerate to 360 kts pull the exact amount of G to stay at that speed and now just wait and outrate the opponent most of the time. The F18 can do that 360 kts turn forever.

It's not strange for aircraft to do this though. Every jet has a corner speed and every speed has a sustained G load.

 

The discrepancy is in how fast aircraft lose/gain knots when they go above or below that G load.

F-16 vs F/A-18C is a cropped delta vs a relatively straight wing with LEX, it's high thrust to weight vs high alpha. The results in-game just don't really add up.

 

Honestly, once the drag gets adjusted for the F-16 to gain quicker, we're probably in a much better spot already. Would most likely even solve the acceleration discrepancies.

[oldtimesake]

The energy addition issue is that the F-16 in DCS requires twice the amount of AOA to pull the same G compared to the real F-16 (induced drag has a  factor of 4). This has been confirmed by ED and they are working on this, but no date is promised.

 

 

 

Also the acceleration issue:

 

[Noctrach]

7 hours ago, Xavven said:

I can find two different sea-level F-16 EM diagrams on a google search (heading of GR1F-16CJ-1-1 and T.O. 1F-16C-1-1). Depending on which one you look at, corner speed is either 0.55 mach or 0.50 (so 330-360 IAS), and Ps = 0 peaks at either 0.78 mach or 0.66 (so 440-520 IAS) right at the 9G line. The slope of the Ps = 0 line is about 0.5 deg./sec. for every 0.1 mach increase in speed until the 9G limit is reached, at which point there's an abrupt negative slope.

 

Sadly, I don't have access to a big array of EM diagrams in a manual that lets me choose the weight, altitude, engine, and drag index I want for any situation, but knowing the general range of these numbers for a few different altitudes is good enough IMO, as there are so many other variables factoring into what kind of turn at what speed you should be doing.

 

I could have bad information, of course, but until someone can get me something better, this is where I'm at. And it might be illegal to share anything anyway.

 

I will say, though, that if the fight starts 2-circle from a neutral pass, even 1 deg./sec. of extra turn rate is something I'll take by flying best STR instead or corner speed, even if it means I'm at the G-limit.

 

Yep, we're reading the same charts. ED originally designated our Viper as F-16CM Block 50, which translates to an F-16CJ with CCIP upgrade and the GE engines. It has a bit more thrust but also a bit more weight than the 16C.

 

If you're starting on a HABFM (neutral) pass with some altitude and you go into 2C flow, I wouldn't stare myself blind on the sustained rate.

Depending on gameplan I'd most likely go into one of the negative Ps curves for instantaneous rate and sustain my speed by going nose low. Gain some angles on the first turn, assess and follow up. (Nose-low sliceback is a classic rate fighter move)

 

This is also incidently why I'm looking at charts of 10,000 ft or above. Altitude is speed, speed is life.

Once you're below 5000 feet you should probably be ending the fight or escaping.

 

Bottom line: horizontal sustained rate fighting is usually sub-par fighting, because you're not max performing your aircraft for either flow. Leave that for when you're still neutral by the time you hit the deck. In real life you'd just be exhausting yourself pulling G's for zero result.

[Youda]

On 4/9/2021 at 10:43 PM, darkman222 said:

sustained G and drag model fixes that are anounced for the F16

On 4/10/2021 at 2:24 PM, Noctrach said:

This has been confirmed by ED and will likely change in the future.

Where pls?

 

On 4/10/2021 at 9:17 PM, darkman222 said:

Although this is an F16 thread here and I am not very used to the F15, but it seems that even in the F15 you'd struggle to outrate the F18 which again stresses that the turn rate of the F18 is too optimistic.

This is indeed true. With current flight models, at sea level with same percentage of fuel the turn rate goes as follows: F-18 > F-15 > F-16

 

Fun fact: If you put just empty pylons on the F-16, its STR decreases by ~10%. If you put pylons on the F-18, its STR stays the same.

[oldtimesake]

Fun fact: If you put just empty pylons on the F-16, its STR decreases by ~10%. If you put pylons on the F-18, its STR stays the same.

--------------------

THIS IS RIDICULOUS

[Top Jockey]

1 hour ago, Youda said:

Where pls?

 

This is indeed true. With current flight models, at sea level with same percentage of fuel the turn rate goes as follows: F-18 > F-15 > F-16

 

Fun fact: If you put just empty pylons on the F-16, its STR decreases by ~10%. If you put pylons on the F-18, its STR stays the same.

 

I've also tested that way in the past, but then I've come to the conclusion that, a more balanced test would be instead:

 

- the fuel quantity for roughly the same flight time (for instance 3 minutes in full afterburner at sea level), for each of the 3 aircraft.

 

It will very likely be a different percentage for each of them.

[wilbur81]

1 hour ago, Youda said:

 

Fun fact: If you put just empty pylons on the F-16, its STR decreases by ~10%. If you put pylons on the F-18, its STR stays the same.

Our current Hornet FM does simulate pylon drag... even when empty.

[Noctrach]

3 hours ago, Youda said:

Where pls?

 

https://forums.eagle.ru/topic/259072-lower-lift-curve-slope-than-in-real-life-more-induced-drag/?do=findComment&comment=4540964

Edited April 12, 2021 by Noctrach

[oldtimesake]

8 hours ago, wilbur81 said:

Our current Hornet FM does simulate pylon drag... even when empty.

But that won't explain why F-16 gets more performance punishment than F-18 from the pylons. 

[wilbur81]

6 hours ago, oldtimesake said:

But that won't explain why F-16 gets more performance punishment than F-18 from the pylons. 

Indeed... that's not my point. The point is that the current Hornet FM does simulate empty pylon drag. Our current Viper is still more W.I.P. than the Hornet. The Hornet came out first... therefore it is going to get more attention until it is complete. They will get both just right...just takes a lot of time.

[Exorcet]

On 4/13/2021 at 12:39 AM, oldtimesake said:

But that won't explain why F-16 gets more performance punishment than F-18 from the pylons. 

I think by default one of the empty pylons for the F-16 is AG configuration, which doesn't help.

 

Also for what it's worth I happened on a video of the Tornado F.3 experience vs F-16 and F-18 (and F-14/15):

 

 

F-16/18 discussion begins at 20:40.

[Hammer1-1]

IMO, and its not worth much, as a regular Hornet driver I can take on an F-16 pilot any day of the week until Im down in the weeds...and then playtime is over. If Im fighting a Viper, I always take it 1 circle, thats on you if you take it. If I fly the Viper, I would always take it vertical against a Hornet; you fight the aircrafts limitations, not its advantages. I see this a lot in my squadron where they just pull back as hard as possible on the stick and expect to out turn me at any speed. No, you cant out turn me. You CAN outclimb me.

 

The Hornet rewards a pilot who isnt afraid to pull back on the stick; thats why it has that extra long LERX. The Viper doesnt have that, so why you doing foolish things like that? And so you know, the Hornets lowest possible airspeed and still maintain stable forward flight without stalling is 60kts. Granted its a 30' drop in altitude for every 5' forward, but thats how well the aircraft handles at slow speed. You cant do that in a Viper; dont even try it.

Edited April 17, 2021 by Hammer1-1

[SCPanda]

On 4/17/2021 at 2:14 PM, Hammer1-1 said:

IMO, and its not worth much, as a regular Hornet driver I can take on an F-16 pilot any day of the week until Im down in the weeds...and then playtime is over. If Im fighting a Viper, I always take it 1 circle, thats on you if you take it. If I fly the Viper, I would always take it vertical against a Hornet; you fight the aircrafts limitations, not its advantages. I see this a lot in my squadron where they just pull back as hard as possible on the stick and expect to out turn me at any speed. No, you cant out turn me. You CAN outclimb me.

 

The Hornet rewards a pilot who isnt afraid to pull back on the stick; thats why it has that extra long LERX. The Viper doesnt have that, so why you doing foolish things like that? And so you know, the Hornets lowest possible airspeed and still maintain stable forward flight without stalling is 60kts. Granted its a 30' drop in altitude for every 5' forward, but thats how well the aircraft handles at slow speed. You cant do that in a Viper; dont even try it.

 

Love your profile picture. Also, I find it hard to beat a Hornet going vertical, because the Hornet seems to gain energy better than the Viper. Also, the Viper loses energy too fast with the current FM due to AOA problems. I find it easier to keep my speed high and spiral climb with the hornet (2 circle), and to a certain point the Hornet cannot keep up with me, so I just cash my energy and drop down to shoot him. 

[Hammer1-1]

I dont see the hornet going vertical. The Viper has a greater t/w ratio and better acceleration in the vertical. Has to be since it absolutely murders the Hornet in rate fights.

[Jester2138]

8 hours ago, Hammer1-1 said:

since it absolutely murders the Hornet in rate fights.

Yeah, in real life. In DCS, with the incorrect F-16 flight model, it does not.

Edited April 20, 2021 by Jester2138