Did the FM get updated?

[rami80]

In this post GGTharos mentions that the issue with the F-15 having more thrust than usual is outdated. Is this confirmed? Did the FM get updated because TRO is still there?

[Silver_Dragon]

The F-15C AFM has on Beta (no finished), surely can be get updated.

[pr1malr8ge]

TRO is being updated supposedly in the next update 1.5 which is DCS world 2 minus the NTTR map..

 

as far as the F-15 having more thrust then usual isn't exactly a true statement.. It was calculated by what numbers they had I.e. Standard day or 15*c @ 0ft MSL. if the actual conditions in game were at that temp then the thrust would be correct. I don't think this is any major advantage though.

Edited September 21, 2015 by pr1malr8ge

[Stuge]

TRO is being updated supposedly in the next update 1.5 which is DCS world 2 minus the NTTR map..

 

as far as the F-15 having more thrust then usual isn't exactly a true statement.. It was calculated by what numbers they had I.e. Standard day or 15*c @ 0ft MSL. if the actual conditions in game were at that temp then the thrust would be correct. I don't think this is any major advantage though.

 

Well, can someone say how much decreased thrust, in percentage, can we expect compared to what it is now? At the moment, F-15C has a significant thrust-to-weight advantage over the Su-27. If this gets more balanced, eagle drivers can't run like chickens anymore :lol:

[pr1malr8ge]

Well, can someone say how much decreased thrust, in percentage, can we expect compared to what it is now? At the moment, F-15C has a significant thrust-to-weight advantage over the Su-27. If this gets more balanced, eagle drivers can't run like chickens anymore :lol:

 

 

Ok, might I ask for you to do some testing on this.. Not saying your wrong but what fuel states are these being stated for..

 

SU27 vs f15 full fuel load OF course the f15c will have a significant TTW over the su27. The f15c is a lighter bird with full fuel. [unless you add bags] Add missiles load outs and the entire thing can be highly changed.. GO full fuel full missile load out against an f15c with only a few missiles and 50% fuel and you're gonna get your ass handed to you in a turning fight even with LEX or the f15c will just extend and you're stuck watching it scream away!

 

Now not sure how exactly the SU27 is modeled in game but irl the f15 also has less parasitic drag then the su27 thanks to flush riveting. Therefor even with an identical gross weight & TTWR the f15 should have better performance in straight & level flight.

 

This is in accordance with Wikipedia listing both jets showing a TTWR of 1.07

 

TTWR isn't a set in stone number for these jets either. the SU27 needs to be clean and @ <5x% fuel for that number. It also is not the only factor determining overall performance either.. Think of it like this.. you take a truck and need to haul 2 20ft trailers both are identical @ 3,000lbs except one has a ^nose the other is a flat nose. Which one do you think will require less fuel to transport over the exact same distance? This is what parasitic drag is to aircraft.

 

 

Personally I think a lot of people are getting all hell bent over the F15 out turning and out running their su27 and claiming NO NO NO it can't happen but never look at what their gross weight is in compared to that of what of the f15 is.

The more weight you have the more G you must pull to keep it in geometry vs the less weighted counter object needs to pull therefor the more energy loss compared to the opposite. the more weight you have the less your TTWR is also.

Edited September 22, 2015 by pr1malr8ge

[GGTharos]

You won't see a significant difference - you MAY be able to percieve it, but for the most part you'll probably need to run a boat-load of science to actually see the difference. And that's just me saying 'I'm going by the charts'.

 

If what I recall is correct, ie. the eagle was tuned to 15deg performance at 20deg weather, yes, there is a performance difference but it is far less significant than people believe it is.

 

It SHOULD be fixed, but the whole thing is being completely blown out of proportion IMHO.

 

To put it into perspective, and this is off-the-top-of-my-head, we're looking at 7-10% more acceleration for STD+10C, compared to standard day (ie. 15C weather). (.. if you want more accurate numbers, get your ruler out, I just don't have time for this any more :P )

 

The 'mis-tuning' is at STD+5C.

 

So, where right now a particular acceleration run should take say, 73-76 sec at SL, it's taking 70 instead.

 

Again, going by memory on the numbers so YMMV. But don't expect miracles.

 

Well, can someone say how much decreased thrust, in percentage, can we expect compared to what it is now? At the moment, F-15C has a significant thrust-to-weight advantage over the Su-27. If this gets more balanced, eagle drivers can't run like chickens anymore :lol:

[Sweep]

Well that's very interesting GG, think you've cleared up some of my fears about future BFM against Flankers! :)

[Stuge]

Hmm, on a hunch I would say that 7-10% decrease would be noticeable definitely.

 

I can tell a simple example of how it is now:

 

I have a habit of sometimes trying to get gun kills on public servers after I run out of missiles.

 

When flying the Flanker, a problem presents itself: when trying to sneak up and gun an unsuspecting Eagle, it is critical that the eagle somehow "cooperates", meaning that it either tries to turn, or is not in afterburner. If it's flying straight and level or, worse, climbing in AB for some reason, there's no chance of catching up. This can even cause problems when chasing for an R-73 shot. Doesn't matter how light I am on the fuel.

 

Now when flying the Eagle chasing down people for gun kills is never a problem. In fact the thing accelerates so ridiculously fast in clean configuration and low fuel, that I feel like I am a missile myself, confident of reaching any target quickly.

[=4c=Nikola]

Well that's very interesting GG, think you've cleared up some of my fears about future BFM against Flankers! :)

 

Better be feared of R-73 off bore capability. :D It's by far the most dangerous feature of flanker during a dogfight.

 

The change in FM might be minor, but it can have a heavy impact at relative performance during some maneuvers. Still, I expect vertical performance to remain roughly the same.

[GGTharos]

And hopefully the 73 will get fixed up to be as dangerous as it should be, too. I believe wags mentioned that there will be a change for the SRMs.

[enigma6584]

As long as the aircraft makes me look good despite my inefficiencies. :smilewink:

[Punisher74]

As far as I understood the F-15C currently is a AFM, now the 1.5 update is supposed to give the F-15C a PFM. As for the trust I've always felt the thrust was too short for the f-15c as the engines in the f-15c produce 2x the thrust to its weight. In the real world the plane is capable of vertical lift without losing power. In DCS there is a loss of power in vertical flight.

[GGTharos]

^^^

 

Another statement without proof.

 

Hate to break it to you, but you are very wrong.

[pr1malr8ge]

As far as I understood the F-15C currently is a AFM, now the 1.5 update is supposed to give the F-15C a PFM. As for the trust I've always felt the thrust was too short for the f-15c as the engines in the f-15c produce 2x the thrust to its weight. In the real world the plane is capable of vertical lift without losing power. In DCS there is a loss of power in vertical flight.

 

Umm.. No the f15 has never had a TTWR of 2... Even with minimum amount of fuel a completely clean aircraft and equipment not needed for basic flight removed to reduce weight [the streak eagle] Only in the lower altitude TTC was a 90* accelerating climb accomplished. In the higher altitude climbs it was nowhere near vertical. This how ever was done using the older original 100 engines and the new ones do have more power and if placed in the streak eagle might possibly produce a TTWR of 2. http://www.pw.utc.com/News/Story/20150218-0945/2015/All%20Categories

 

Now with that being said in the combat ready f15c we fly in DCS that weighs much more then that of the Streak Eagle we will never be able to

accelerate in a pure vertical climb & we will never see a TTWR above probably 1.3

[TAW_Blaze]

And hopefully the 73 will get fixed up to be as dangerous as it should be, too. I believe wags mentioned that there will be a change for the SRMs.

 

Is this a flare resistance related problem or something else?

[aceviper]

@GGTharos....swing away:megalol:

[Punisher74]

Umm.. No the f15 has never had a TTWR of 2... Even with minimum amount of fuel a completely clean aircraft and equipment not needed for basic flight removed to reduce weight [the streak eagle] Only in the lower altitude TTC was a 90* accelerating climb accomplished. In the higher altitude climbs it was nowhere near vertical. This how ever was done using the older original 100 engines and the new ones do have more power and if placed in the streak eagle might possibly produce a TTWR of 2. http://www.pw.utc.com/News/Story/20150218-0945/2015/All%20Categories

 

Now with that being said in the combat ready f15c we fly in DCS that weighs much more then that of the Streak Eagle we will never be able to

accelerate in a pure vertical climb & we will never see a TTWR above probably 1.3

 

Well even today the f-15c in the real world can climb vertically, but the f-15c in DCS doesn't at takeoff. I maybe get about 10,000ft. In the video link you'll see the f-15 climb up way farther then in game and still have enough power to preform then maneuvers required to level out. I can guarantee the altitude speed and maneuvers cannot be recreated in game without stalling.

 

[sobek]

a) He's not climbing vertically in that video, maybe 60 or 70°

 

b) He's taking the full runway length to pick up speed

 

There's some additional bit of info you need to account for, the engines produce more thrust when you are flying at a certain speed due to the added compression.

 

I can guarantee the altitude speed and maneuvers cannot be recreated in game without stalling.

 

You completely neglect to mention what loadout you use, under what atmospheric conditions, etc.

You can't expect to pull up from TO speed and dart straight up into the air while accellerating, especially not if your plane is loaded.

Edited September 23, 2015 by sobek

[=4c=Nikola]

@raptorsim: That video is useless without meteo conditions and load configuration.

 

In DCS, if you take clean eagle with 30% of fuel and set best density altitude, you can reach 45-50k ft with the profile from the video (about 60 degrees climb after runway acceleration).

[GGTharos]

You can't guarantee anything because you have no speed, attitude or altitude readout.

 

About the only thing that is guaranteed here is that you don't know how to perform this type of take-off.

 

Track of similar climb profile included. I'm only guessing the parameters, but I'm probably fairly close.

 

Grab a -1 and PROVE that the eagle isn't up to snuff. Until you do that, you're basically talking nonsense.

 

Well even today the f-15c in the real world can climb vertically, but the f-15c in DCS doesn't at takeoff. I maybe get about 10,000ft. In the video link you'll see the f-15 climb up way farther then in game and still have enough power to preform then maneuvers required to level out. I can guarantee the altitude speed and maneuvers cannot be recreated in game without stalling.

f-15climb.trk

Edited September 23, 2015 by GGTharos

[pr1malr8ge]

Well even today the f-15c in the real world can climb vertically, but the f-15c in DCS doesn't at takeoff. I maybe get about 10,000ft. In the video link you'll see the f-15 climb up way farther then in game and still have enough power to preform then maneuvers required to level out. I can guarantee the altitude speed and maneuvers cannot be recreated in game without stalling.

 

 

First and foremost, I never said the airplane would not ascend in a 90* perpendicular to earth attitude. What I said was an accelerated climb in the vert will not happen. Take off accelerate to 500kts pull 5gs to the vert and it will climb due to inertia, But it will NOT GAIN SPEED!