Max speed Mach 1.6

[bkthunder]

EDIT: Track attached and more testing

EDIT 2: EXCESSIVE PYLON DRAG! All numbers below are referring to an aicraft with no payload but pylons. Tried again withotu pylons and numbers are closer to the charts. Gone is the weird behavior between 43-50k feet.

Pylons have no weight (from ME loadout screen) but make a big drag difference!

 

US standard day, 22k lbs, no external loads

 

At 38.000 ft, the aircraft reaches a max speed of M 1.75 after several minutes of veeeery slow acceleration.

At 40.000 ft, max speed is still M 1.74-1.75

At 43.000 ft, max speed is still M 1.74-1.75, but at this point a strange behavior manifests itself (see below)

 

Keeping full AB at M 1.75 @ 38.000 feet, I start a slow climb past 40k feet, at around 43.000 feet mach number starts to pick-up quickly up to mach 2.2 as I climb through 45.000k. It holds mach 2.2 up until ~52.000 feet and then suddenly and very quickly IAS drops in the 350s kts and mach drops to 1.6.

 

I descent again to 43.000k (the altitude at which during the climb I attained M 2.2, but the speed now tops at M 1.73-1.75.

 

I redo the procedure and the same behavior shows: slow at 38-43k feet, then sudden acceleration past mach 2, then at 50k sudden deceleration as if the engine lost power.

However, If I maintain 43.000 feet and try to accelerate there, I can never achieve more than 1.74-1.75.

So it looks like there's some strange zoom-climb behavior or something.

 

For reference:

 

Top speed at 30k feet should be Mach 1.89

Top speed at 38k feet shoudl be just shy of Mach 2.0

Top speed at 40k feet should be Mach 2.00

At 50k feet max speed shuould still be just shy of Mach 2.0

F-16 max mach oddities.trk

Edited November 10, 2019 by bkthunder
further testing

[Raven (Elysian Angel)]

I've taken the F-16 to just over M2.0 with 2x CAP-9Ms loaded, at 36,000ft.

[D4n]

Did u both use default weather setting, does air-temperature matter regarding engine power?

[Kazansky222]

I've taken it past mach 1.7 with 2 120s at 45-50k feet.

[D4n]

ah, nice

[Eldur]

 

The maximum I've been able to get out of the Viper on a DCS standard day in Caucasus, Buno 38756 (second most recent version ATM). That's closer than the Tomcat, which still is too slow by a bigger margin (2.15 max vs 2.34+ official). Airframe was totally clean with innermost pylons, after dropping bags (went up without AB, then lit the cans to make most use of the bags, got up to somewhere around 1.62ish with them at 42k ft, then slowly went down to 36500-37k ft after jett), fuel state around 4.7ish. Was still accelerating veeery slowly though I just had to quit due to time restrictions. Probably could have reached 2.0 if I had flown for like half an hour more.

Edited November 10, 2019 by Eldur