F-14B acceleration correct?

[Donut]

Does anyone think that the current acceleration of the F-14B is a little slow?  I know there are FM tweaks in the works but Heatblur has mentioned  that there really isn't much more to change and the current FM is pretty much spot on accurate.

 

I ask because I have seen several acceleration tests done online and the results have the Hornet out accelerating the Tomcat at everything below Mach 1.  Everything I have heard over the years would make this seem unlikely.  In my very unscientific testing, I have both the Hornet and Tomcat clean and full fuel takeoff at full AB and mark the speed by the end of the runway...Hornet beats it every time.  
 

Is the F-14B engine and drag modeling correct and the acceleration

seen in DCS true to life?  

 

Thank you for the replies and discussion.

[Skysurfer]

It's WIP currently. Has been for months now, sadly.

Edited April 10, 2021 by Skysurfer

[maxsin72]

Almost 6 months passed and the problem was still not fixed, It's really very sad. Just today, with my F14B,  i had several 1vs1 vs a good F18 pilot in multiplayer and, even if had more speed at the beginning, the f18 in levelled flight was able to accelerate and undertake my speed or also go for vertical and climb much more then me even if i was starting climbing with more speed: at the beginning i was able to see the F14 come closer but then the f18 was able to have more speed and climb higher. All this with clean configuration and with 4000 lbs of fuel or less.

[Donut]

Another thing to mention is that real life Hornet pilots have mentioned that the current Hornet FM is a bit draggy and slow in acceleration...this would make it even quicker than the Tomcat currently.  It will be interesting to see the updated FM with 2.7 on Wednesday.  I know the Tomcat is not getting an FM update this patch though.

[Skysurfer]

1 hour ago, N0430BM said:

Another thing to mention is that real life Hornet pilots have mentioned that the current Hornet FM is a bit draggy and slow in acceleration...this would make it even quicker than the Tomcat currently.  It will be interesting to see the updated FM with 2.7 on Wednesday.  I know the Tomcat is not getting an FM update this patch though.

 

I have heard quite the opposite. Our Hornet is pretty overpowered in terms of top speed and acceleration in most configurations. 

[Donut]

23 minutes ago, Skysurfer said:

 

I have heard quite the opposite. Our Hornet is pretty overpowered in terms of top speed and acceleration in most configurations. 

I have heard that about the Hornet's turn rate but not power/acceleration.  Not saying you are wrong, but if you are right...the Hornet is a real pig then.  
 

Compared to it's teen fighter peers in DCS, the Tomcat has the slowest subsonic acceleration.  This may be true to life and I am just misinterpreting the supposed Tomcat's speed superiority or the FM of all the others are way off.

Edited April 12, 2021 by N0430BM

[Skysurfer]

22 minutes ago, N0430BM said:

I have heard that about the Hornet's turn rate but not power/acceleration.  Not saying you are wrong, but if you are right...the Hornet is a real pig then.  
 

Compared to it's teen fighter peers in DCS, the Tomcat has the slowest subsonic acceleration.  This may be true to life and I am just misinterpreting the supposed Tomcat's speed superiority or the FM of all the others are way off.

 

 

The Hornet is a strike fighter and has tremendous high alpha and slow speed controlability in BFM. Different requirements. Apples and oranges.

[Spurts]

IRL the Hornet has fantastic subsonic acceleration.  I've heard that the -402 Hornets (like we have in DCS) match an F-15 in subsonic acceleration.

[Donut]

Here is some great data and analysis about transonic acceleration...
 

https://forums.eagle.ru/topic/267242-f-14a-acceleration-data-comparison/

 

My original post was more about subsonic acceleration but the above points to acceleration issues in all flight regimes in DCS.  If the A is that far off, the B may be as well.  Also of note, the DCS Hornet is actually slower than the real life data on the A Hornet...this makes no sense because the A and C are the same airframe but the C has upgraded engines, which should make it quicker in acceleration...this is not seen in DCS.  
 

What we can gather from all of this is that the DCS Hornet is currently underpowered and/or over draggy, meaning it should be even faster in acceleration than the DCS Tomcat than it already is.  

 

 

[Spurts]

7 minutes ago, N0430BM said:

 

What we can gather from all of this is that the DCS Hornet is currently underpowered and/or over draggy, 

 

 

If a module is too slow in acceleration but too fast on the top end then the issue is being underpowered and under draggy.  there is a lot to try and balance with these things.

[ustio]

No is not.

 

Something went wrong when they change the drag value. And unfortunately its not a priority fix atm

[fat creason]

6 hours ago, ustio said:

unfortunately its not a priority fix atm

 

Well this is news to me, the fact that I'm working on it (and have been) as I write this post says otherwise.  Just because a fix is not immediate does not mean it's not a priority. If you've read any of my posts regarding the FM updates you would already know it's going to take time to fix.

Edited April 13, 2021 by fat creason

[ustio]

Well glad to hear that.

seeing that you close the "turn rate tanked" thread and how Ironmike respond gives me the impression that it isn't

Edited April 14, 2021 by ustio

[fat creason]

Assumptions get passed around on this forum as fact quite frequently. You're aware of the saying about assumptions, no?

[maxsin72]

19 hours ago, fat creason said:

Assumptions get passed around on this forum as fact quite frequently. You're aware of the saying about assumptions, no?

Do you have an approximate ETA for the FM update? Thanks

Edited April 15, 2021 by maxsin72

[Victory205]

Tuesday. 

[Slant]

On 4/14/2021 at 1:04 AM, fat creason said:

 

Well this is news to me, the fact that I'm working on it (and have been) as I write this post says otherwise.  Just because a fix is not immediate does not mean it's not a priority. If you've read any of my posts regarding the FM updates you would already know it's going to take time to fix.

 

 

Ha, this is a good study case to explain the difference between the concepts of "importance" vs. "urgency".

[maxsin72]

10 hours ago, Victory205 said:

Tuesday. 

The real story is:

 

Monday, I could wait till Tuesday
If I make up my mind
Wednesday would be fine, Thursday's on my mind
Friday'd give me time, Saturday could wait
But Sunday'd be too late

 

... and so 6 months passed and the Tomcat is still tanked...

Edited April 15, 2021 by maxsin72

[Donut]

On 4/13/2021 at 9:33 AM, Spurts said:

IRL the Hornet has fantastic subsonic acceleration.  I've heard that the -402 Hornets (like we have in DCS) match an F-15 in subsonic acceleration.

Thanks for the info.  Doing some research online, I have found this may be close to correct as well.  There are too many resources to quote and no way am I posting anything here...but what I found makes me actually believe the DCS Tomcat subsonic acceleration may be accurate or close to it and the Hornet in DCS is too slow.  I know this is all very complex and one must be careful about what they read online, so I will leave it to the experts and trust that in the end we will get accurate representations of each aircraft's real life performance.

[Victory205]

A clean FA18C out accelerates an F14A significantly in the subsonic realm. It's when you add the ever-present F18 C/L tank where things get a little more even. The little Bumblebee could go, but it ran into a wall.

 

The real difference is the transonic and supersonic range. The fixed inlets and fixed wing on the Hornet vs the increase in ram air thrust from the efficient variable engine inlets, coupled with the drag reduction from the 68 degree wing sweep, allowed the F14 to have a much higher top end and made it quicker to get there. The F18EF, because of their pylon configuration makes that aircraft even slower.

 

You are right to look at all of this with a wary eye. I could fill volumes with some of the BS that is repeated out there by social media geniuses who just make it up on a whim.

 

One thing to keep in mind, the performance charts are estimates based on data points extrapolated from flight test. The very high mach realm was almost never sampled except on PMCF flights, and the last thing the crew was doing was timing the acceleration for later correlation. The accel was never done level as per the charts either, because doing a level accel wasted too much time, airspace and fuel, nor were the extreme high mach numbers commonly reached. The A had a 1.88 limit, go beyond it and if something went wrong, you were going to be defending your career. The reason you were doing the Mach run was to check the Mach Levers at idle thrust while above 1.5IMN. Also, a post maintenance check flight never carried weapons to match the charts, so don't think the acceleration performance was verified by Fleet pilots.

 

Different story on tactical bug outs at relatively low altitudes. We got to those max Mach numbers routinely when doing NFWS, Red Flag, FFARP, DACT, etc. because were were clean and working from ashore.

 

If we were carrying anything close to one of the charted performance weapons load outs, then we were likely on cruise, with tanks, saving fuel on CAP in case we needed it for combat, not wasting it on speed runs for glory. 

 

Hope this make sense.

Edited April 16, 2021 by Victory205
Clarity

[Kula66]

5 hours ago, Victory205 said:

A clean FA18C out accelerates an F14A significantly in the subsonic realm.

 

Thanks Victory205, and how would that compared to a 14B in the subsonic realm?

[Figaro9]

Specific excess power at 10kft , Mach 0.9, Standard day, 60% Fuel:

F-14A TF 30: Ps= 500ft/s (4 winders, 4 Sparrows)

F-14D F110 : Ps = 640 ft/s (4 /4 )

 

F-18A Lot1: Ps= 617ft/s (2/2) 400 engine

F-18C Lot14:  PS= 599ft/s (2/2) 400 engine 

 

F-18C Lot15:  PS= 699ft/s (2/2) 402 engine 

F-18C Lot19:  PS= 695ft/s (2/2) 402 engine

 

F-18E :  PS= 661ft/s (2/2) 

Edited April 16, 2021 by Figaro9

[Spurts]

a 2/2 hornet is effectively clean, but those number do speak volumes about the performance of the 402 motors.  Nearly a 17% improvement in SEP at 0.9M over the 400s.  

3 hours ago, Figaro9 said:

Specific excess power at 10kft , Mach 0.9, Standard day, 60% Fuel:

 

 

Any chance of similar numbers at other speeds?  .6M and 1.2M perhaps?  really show the subsonic vs transonic impacts.

[Skysurfer]

4 hours ago, Figaro9 said:

Specific excess power at 10kft , Mach 0.9, Standard day, 60% Fuel:

F-14A TF 30: Ps= 500ft/s (4 winders, 4 Sparrows)

F-14D F110 : Ps = 640 ft/s (4 /4 )

 

F-18A Lot1: Ps= 617ft/s (2/2) 400 engine

F-18C Lot14:  PS= 599ft/s (2/2) 400 engine 

 

F-18C Lot15:  PS= 699ft/s (2/2) 402 engine 

F-18C Lot19:  PS= 695ft/s (2/2) 402 engine

 

F-18E :  PS= 661ft/s (2/2) 

 

 

Source? I.e. where did you get these numbers from?

[Victory205]

LOL, I love the numbers- 599, 661 ft/sec... Are you sure it’s not 598 or 662? The width of the lines on some of the charts are 20 ft/sec. 

 

I don’t have an F14B/D low speed acceleration matrix like the F18 and F14A, so can’t provide a comparison. It’s important that when you don’t know, to say that you don’t know. The F18E/F are going to show lower accel and Mmax when pylons are installed.

 

Most of you are aware that the wing pylons are angled out to facilitate safe weapons employment and jettison separation, which increases drag commensurately.

 

Also, referencing the OP’s drag race that began on the runway aren’t valid given the DCS wheel drag anomalies. 

 

Again, we’re working on all of this.