investigating F-16 F110 Underperforming in Mil Power

[Exorcet]

For a while now I've felt like the mil power performance of the F-16 was a little low, though I chalked it up to the DCS version being Blk 50 as the GE engines favor AB over dry thrust.

However I did finally get around to do some testing and it looks like there is a lack of thrust/overprediction in fuel flow even taking into account the F110's.

I have tracks attached, though due to forum rules I am not posting the source info. I can send it via message.

Summary of the issue:

Testing at DI 102 at 34015 lbs weight to compare to data at DI 100 at 34000 lbs weight

DCS shows increased Delta between speeds when accelerating under full mil power. This not only impacts acceleration, but climb and cruise, so the F-16 has a harder time getting to optimum altitude and uses too much fuel when cruising.

DCS fuel burn at 510 knots is approximately 4200 PPH while the actual value should be just under 3900 PPH.

Ideally some more testing is needed to see if this is more of an engine issue or drag issue, and it should be tested at more speeds, altitudes, and weights, but the condition that I did test is an important one as it's relevant to the F-16 in a CAP role.

F-16CFuelFlow_35000FT_102DI.trk F-16CMilAccel_30000FT_102DI.trk

[darkman222]

7 minutes ago, Exorcet said:

engine issue or drag issue

I am particularly interested if it turns out that the drag is the cause for that...

[Exorcet]

2 hours ago, darkman222 said:

I am particularly interested if it turns out that the drag is the cause for that...

Comparing AB to Mil in acceleration it looks like it's probably thrust. AB accel is much closer to the real jet, especially when supersonic. Subsonic accel was slightly underperforming, but that was probably because of imperfect flying when the jet is close to stall at the low starting speed.

[Lord Vader]

Hello @Exorcet

What values are you using to base your tests? In other words, where is the "(data)" entry coming from?

Please send that information to @BIGNEWYvia private messaging. 

Thanks for your cooperation.

[Exorcet]

Data has been sent.

[Exorcet]

This is still labeled as "PM Evidence" so I wanted to follow up. Do you need more source information?

[BIGNEWY]

Hi Exorcet, 

thank you for the PM, we will take a closer look, but our initial test show our data is correct. 

We will check for drag issues or other anomalies. 

thank you 

[Exorcet]

59 minutes ago, BIGNEWY said:

Hi Exorcet, 

thank you for the PM, we will take a closer look, but our initial test show our data is correct. 

We will check for drag issues or other anomalies. 

thank you 

Thanks for the confirmation. The F-16 model is quite good. This is not a massive error, and my flying wasn't perfect, so if it's deemed to be within tolerances I can understand.

[Spartan111sqn]

yes, my feeling is more in the drag, induced by AoA or stores, I do not know, but there is something, hornet RL pilot told me that with same loadout vipers and hornets (2xbags and empty pilons), both in MIL they were never able to catch them when in formation flying and accelerating in MIL.

 

Just for give you a hint.

[Furiz]

All I hear about Viper engine is that is very powerful, great acceleration etc etc, I can't speak from personal experience or give any evidence but DCS gives me the feeling that Viper is struggling with drag more than other planes.