correct as is From Landing gains to cruise gains and behaviour on ground.

[greenmamba]

Hello DCS community,

Did you guys noticed the transition that is noticeable when the aircraft transitions from landing gains to cruise gains ? almost as if the aircraft wants to pitch up by itself ?

Behaviour on ground: it really feels wrong, i do not have fighter time but i have jet engine time and the way the F-16 behaves on the ground feels really off, especially on landing with no wind, it is almost impossible to brake evenly and keep it straight on the runway, i almost always find myself skidding down the runway with one rudder pedal almost fully deflected while trying to brake. The airplane has in general a tendency to weer off the centerline, this is normal in most airplanes but here i feel it is exagerated. 

It is very hard to do aerodynamic breaking; especially for people who have FSSB sidestick, it requires a huge amount of back stick pressure to keep the nose in the air after landing .. too much if you ask me.

In most airplanes you have to apply a bit of differential braking and at the same time some rudder inputs to keep it on the centerline, but here it really feels off. But in DCs i feel like i loose control of the airplane very easily on ground, airplanes don't skid like if they were on ice like that.

 

other users feedback welcome and i would like to know what you think and if this is something ED could please have a look into it ? 

[BIGNEWY]

Hi, 

please attach a track replay example and any evidence you have. We can not look to make changes based on feelings,

we use real world data / physics calculations and SME feedback. 

thanks

[greenmamba]

Hi,

I am not an F-16 Pilot, whar kind of evidence are you asking for from me ? except that i can tell you that an airplane does not skid off the runway like that ? That an airplane does not require such differential braking to not skid off the centerline in no wind condition ? apart from my real life airline pilot experience on Airbus i can not give you any kind of evidence, i can give you a track, but it will be the same as for the rest of the community. 

[BIGNEWY]

1 minute ago, greenmamba said:

Hi,

I am not an F-16 Pilot, whar kind of evidence are you asking for from me ? except that i can tell you that an airplane does not skid off the runway like that ? That an airplane does not require such differential braking to not skid off the centerline in no wind condition ? apart from my real life airline pilot experience on Airbus i can not give you any kind of evidence, i can give you a track, but it will be the same as for the rest of the community. 

Can you attach a short track replay example showing the issues, we may be able to give you some pointers. Could you be over weight for landing maybe? 

[greenmamba]

Okay i will show you my track, from there we can maybe look into things. No, not overweight, i land with maximum 3000 pounds of fuel in the tanks. 

[greenmamba]

Here,

this is a short mission, clean jet, caucasus map, no wind, no weather.

At rotation i am pulling the nose up to go search por the 10°, then while i do that i raise the gear and you can see the pitch up tendency, not my input.

On landing on purpose i tryied to butter kiss it, tried to keep the nose high, impossible unless you rip the stick and the desk with you. Once the nose came down i applied brakes evenly, as much as i could and see how the airplane veers off to the left of the runway ...without any inputs and i release the brake pressure completely, no rudder inputs and the aircraft makes a pirouette on the runway. 

 

 

test.cf

[BIGNEWY]

29 minutes ago, greenmamba said:

Here,

this is a short mission, clean jet, caucasus map, no wind, no weather.

At rotation i am pulling the nose up to go search por the 10°, then while i do that i raise the gear and you can see the pitch up tendency, not my input.

On landing on purpose i tryied to butter kiss it, tried to keep the nose high, impossible unless you rip the stick and the desk with you. Once the nose came down i applied brakes evenly, as much as i could and see how the airplane veers off to the left of the runway ...without any inputs and i release the brake pressure completely, no rudder inputs and the aircraft makes a pirouette on the runway. 

 

 

test.cf 1.15 MB · 0 downloads

Hi, 

sorry I'm not sure what the file type is above (.cf)? 

could you do a landing in a air start short mission and when you exit the mission during the debrief you can save the track replay to attach, we can watch it back on our machines then. 

thank you  

[greenmamba]

Hi,

Sorry, my bad .....uploaded the wrong file, here is the file.

 

Landing test.trk

[greenmamba]

Starting at 2:50, F-16 landing ans use the aerodynamic braking by keeping the nose high. In DCs starting at 140+ knots the nose just falls down to the ground when actually you can keep it up to 100 knots for C models and 90 knots for A models, rough numbers. 

[BIGNEWY]

Hi, 

thank you for the track replay, we have taken a look. Just some observations, you maybe over and under controlling at times. You pull back a little to much, and then the nose comes forward, you are applying 100% brakes which compresses the nose gear, which induces a slight bounce which causes it to veer off the centre line, after you activate the nose wheel steering the jet is already out of shape and you start applying right pedal which cranks the nose wheel hard and causes the spin at the end. 

It is important to be smooth with the landing and inputs, the F-16 is a small jet with a very narrow landing gear footprint so any over or under correction will be punishing. 

When we test we are not seeing any issues with the behaviour on landing or ground handling. 

thank you 

[Raisuli]

28 minutes ago, BIGNEWY said:

Hi, 

thank you for the track replay, we have taken a look. Just some observations, you maybe over and under controlling at times. You pull back a little to much, and then the nose comes forward, you are applying 100% brakes which compresses the nose gear, which induces a slight bounce which causes it to veer off the centre line, after you activate the nose wheel steering the jet is already out of shape and you start applying right pedal which cranks the nose wheel hard and causes the spin at the end. 

It is important to be smooth with the landing and inputs, the F-16 is a small jet with a very narrow landing gear footprint so any over or under correction will be punishing. 

When we test we are not seeing any issues with the behaviour on landing or ground handling. 

thank you 

Thanks, BN!  F-16 loves to dance for me, too, and I've always assumed the nut behind the stick was a little loose.  That's been slowly improving as my flight time increased, but this provides some concrete cause and effect to think about beyond over-correcting (which I do) and getting ham-ankled with the brakes.  I don't expect that nut to get any tighter, but maybe the guys in the tower won't hurt themselves falling down laughing every time I land...

[BIGNEWY]

23 minutes ago, Raisuli said:

Thanks, BN!  F-16 loves to dance for me, too, and I've always assumed the nut behind the stick was a little loose.  That's been slowly improving as my flight time increased, but this provides some concrete cause and effect to think about beyond over-correcting (which I do) and getting ham-ankled with the brakes.  I don't expect that nut to get any tighter, but maybe the guys in the tower won't hurt themselves falling down laughing every time I land...

It takes a lot of practice and repetition to get it perfect, and I am not great at it either. I will stick to my AH-64D for my daily driver

[Raisuli]

39 minutes ago, BIGNEWY said:

It takes a lot of practice and repetition to get it perfect, and I am not great at it either. I will stick to my AH-64D for my daily driver

Oh, we really need to talk!  The AH-64 is out to get me...

[greenmamba]

so i guess i need to reduce the sensitivity of my rudder pedals and brakes, thanks for the inputs.