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gray eagle
December 24th, 2014, 10:09
Looking for guidance on how to remedy the forward creep that the Harrier does when it pops in at your fav airport. It already starts with the engine running and creeps forward till I hit the CTRL + .
to stop it.

Still practicing at the airfields with assent and decent with the nozzles before I try to land on a LHA. I manage to drop too fast on the ground and it bounces a bit.
Gotta get the technique down on throttle control during decent.

DaveB
December 24th, 2014, 14:00
Hmm..
I have this one and the Wilco model and I think they both do it if your nozzles aren't back a touch. They default fully aft don't they (don't have either installed at the moment) so you could either move the nozzles toward the stol/vtol setting or keep it on the parking brake until you want to move. There are other options but these are probably the easiest:)

EDIT: Sri.. I've just noticed you've said brake creep. I can't remember either creeping on the brakes. You can either increase the braking efficiency in the cfg or pull the nozzles forward as mentioned.
ATB
DaveB:)

gray eagle
December 24th, 2014, 14:07
Hmm..
I have this one and the Wilco model and I think they both do it if your nozzles aren't back a touch. They default fully aft don't they (don't have either installed at the moment) so you could either move the nozzles toward the stol/vtol setting or keep it on the parking brake until you want to move. There are other options but these are probably the easiest:)

EDIT: Sri.. I've just noticed you've said brake creep. I can't remember either creeping on the brakes. You can either increase the braking efficiency in the cfg or pull the nozzles forward as mentioned.
ATB
DaveB:)


I understand the first part about the nozzles but not sure what you mean or what cfg to edit and how or what to change.

Edit: Moving the nozzles full down doesn't keep the plane from moving forward, unless you use the brake then when you release brake it starts forward movement.
A CTRL + . will bring it to a complete stop.

StormILM
December 24th, 2014, 14:36
The part of the config you need to change is in the brakes section. Increasing the number will make it more effective & lowering, less effective. The other thing to note is that with the landing gear contact points as they are, FS9 & FSX Harrier models have notoriously bad or quirky ground handling & braking. It's a limitation of the sim.

[brakes]
parking_brake = 1
toe_brakes_scale = 1.5 //<----
differential_braking_scale = 0.0
auto_brakes = 0
hydraulic_system_scalar = 1

DaveB
December 24th, 2014, 15:29
I understand the first part about the nozzles but not sure what you mean or what cfg to edit and how or what to change.

Edit: Moving the nozzles full down doesn't keep the plane from moving forward, unless you use the brake then when you release brake it starts forward movement.
A CTRL + . will bring it to a complete stop.

Right.. so with parking brakes on, it stays put. When you release the brakes.. it creeps forward. That's not brake creep:) Storm's suggestion will make the brakes sharper but it won't stop the model creeping forward with the brakes off. As he said.. all Harriers tend to be a little 'untidy' as FSim doesn't care much for VTOL so compromises have to be made.
Will the nozzles not go beyond down.. eg, slightly forward? I'm sure this stops the creep on one of the models but I can't remember if it's this one or the Wilco model:banghead: As I said above.. I don't have either installed on my fresh FSX install as I don't have a throttle quad and using keystrokes to control the nozzles was too hit and miss.. you need another hand!:biggrin-new:

Sri this hasn't been much help.
ATB
DaveB:)

gray eagle
December 24th, 2014, 15:42
The part of the config you need to change is in the brakes section. Increasing the number will make it more effective & lowering, less effective. The other thing to note is that with the landing gear contact points as they are, FS9 & FSX Harrier models have notoriously bad or quirky ground handling & braking. It's a limitation of the sim.

[brakes]
parking_brake = 1
toe_brakes_scale = 1.5 //<----
differential_braking_scale = 0.0
auto_brakes = 0
hydraulic_system_scalar = 1


toe_brakes_scale = 1.5 //<----
I've tried all manner of values, ascending and descending and to no avail did it have any effect or remedy the issue i.e., the plane keeps rolling forward in idle.


As an aside, the KBT P-3 Orion does the exact same thing.

gray eagle
December 24th, 2014, 15:44
Right..
Will the nozzles not go beyond down.. eg, slightly forward? I'm sure this stops the creep on one of the models but I can't remember if it's this one or the Wilco model:banghead: As I said above.. I don't have either installed on my fresh FSX install as I don't have a throttle quad and using keystrokes to control the nozzles was too hit and miss.. you need another hand!:biggrin-new:

Sri this hasn't been much help.
ATB
DaveB:)


For lack of a better definition, I used the term brake creep. I don't know any other term/s to call it. But, I think I have described the malady....:)
I thought of that and the nozzles will go slightly forward but that didn't stop nor slow the plane.

DaveB
December 24th, 2014, 16:03
Sri mate.. it must work better on the Wilco model. Sadly.. it may well be something you'll have to live with:( If it's any consolation.. the Razbam model is much easier on FR's and has some great external views. The FD is certainly quirky though both have their pluses and minuses.

ATB
DaveB:)

Deacon211
December 25th, 2014, 17:36
Are you saying that the jet creeps forward even with the wheel brakes engaged but with the parking brake off? I never noticed that.

If makes you feel any better, you don't sit with the nozzles straight down for very long in the actual jet...it will melt the tires (or at least blow the fusible plugs). IIRC, you normally taxiied with nozzles 10. I can't recall quite why.

gray eagle
December 26th, 2014, 04:33
Are you saying that the jet creeps forward even with the wheel brakes engaged but with the parking brake off? I never noticed that.

If makes you feel any better, you don't sit with the nozzles straight down for very long in the actual jet...it will melt the tires (or at least blow the fusible plugs). IIRC, you normally taxiied with nozzles 10. I can't recall quite why.

Yes, I am saying that the jet rolls fwd all on it's on unless I invoke the ctrl + . keys.

Well fortunately, in FSX land, there are no tires to melt - it's just pretend yes? Another FSX (Pretend) aircraft that does the very same thing is KBT's P-3 Orion; It too rolls forward with 0% throttle
unless you apply the brakes.

Deacon211
December 27th, 2014, 11:33
Yes, I am saying that the jet rolls fwd all on it's on unless I invoke the ctrl + . keys.

Well fortunately, in FSX land, there are no tires to melt - it's just pretend yes? Another FSX (Pretend) aircraft that does the very same thing is KBT's P-3 Orion; It too rolls forward with 0% throttle
unless you apply the brakes.


Well, see there's my question.

The aircraft should not roll at idle with the pedal brakes on, but it may very well roll at idle with the pedal brakes off. That big turbofan has pretty high idle thrust.

So, I guess what I'm asking at is: Does the jet roll with your feet on the brakes, but with the parking brake off? Or does the jet roll with your feet off the brakes with the throttle at idle? If the jet doesn't roll with the parking brake but does with just the pedal brakes, then yes that is an issue. But if it's the second case, then (as far as I can remember) that's not abnormal for the Harrier at least at relatively light loadings, though it may be unusual for FSX where it sometimes feels like you are stuck in the mud.

Just trying to determine if the bug is a bug....or a feature. ;)


BTW, the Harrier will absolutely skid the wheels at much above 60%, which is why you run the throttle to mil to check the acceleration, but quickly retard it to about half to keep from rolling off.

DaveB
December 27th, 2014, 11:57
I've read this thread so many times now I'm convinced he's saying that the Harrier creeps forward with the engine running and the brakes off.. ANY brakes off.:) I'm pretty sure it's normal for this model. He mentioned the Orion doing it too and while I don't have that model.. I've seen it happen on turbo props before though the reasons for it happening are probably different.

ATB
DaveB:)