brakes engage on landing

[newtie 533]

Hi-

I notice that the brakes on the 35 engage on landing all by themselves. Very odd.

I do have the latest download of the 35 in V5 btw.

What setting have I screwed up that would cause thi :>)

Cheers,

Mark

[ark 1,291]

1 hour ago, newtie said:

Hi-

I notice that the brakes on the 35 engage on landing all by themselves. Very odd.

I do have the latest download of the 35 in V5 btw.

What setting have I screwed up that would cause thi :>)

Cheers,

Mark

Check you don't accidentally have the emergency brake on (red knob on left side of throttle quadrant).

What do you have set up to apply the brakes normally -- something like Saitek rudder pedals/brakes, or do you use a key, or what?

And are you using FSUIPC?

Al

 

Edited August 21, 2020 by ark

[newtie 533]

Hery Al-

Emergency knob in up position.

Saitek rudder pedals set up in P3D, not FSUIPC.

Just flew from KABQ to KTVL and upon landing, I gently apply the brakes and they lock up until the ac completely stops. I then press the toe brakes and they will release.

The only thing I can think of, which may have nothing to do with this, is AccuFeel. I'll disable this for this ac tomorrow on a shorter haul and let you know. Unless you figure this out first :>)

Thanks,

Mark

[ark 1,291]

21 hours ago, newtie said:

Hery Al-

Emergency knob in up position.

Saitek rudder pedals set up in P3D, not FSUIPC.

Just flew from KABQ to KTVL and upon landing, I gently apply the brakes and they lock up until the ac completely stops. I then press the toe brakes and they will release.

The only thing I can think of, which may have nothing to do with this, is AccuFeel. I'll disable this for this ac tomorrow on a shorter haul and let you know. Unless you figure this out first :>)

Thanks,

Mark

Strange. Probably worth double checking that you have the brakes Reverse boxes checked in the P3D axis assignment tab although if the brakes eventually release I doubt that is the problem.

Also make sure there is no other controller or brake assignment that might be interfering with the Saitek brakes. Maybe some kind of autobrake setting assocaited with an airliner that has autobrakes which are activated when landing. I see P3D has Autobrake key assignment options.

If when sitting on the runway without moving you press the brakes, do they release as expected?

If when moving on the ground, say during the takeoff roll or taxiing and you apply the brakes with the . (period) key, but not long enough to come to a stop, do they release when you release the key, but not if you do the same test when using the Saitek brakes?

Does this brake problem seem to only happen in the Lear35?

Al

 

Edited August 22, 2020 by ark

[newtie 533]

Hi Al-

Here's what I've done so far.. Loaded a single prop Carenado, flew that brakes do not engage on landing.

Removed FSUIPC.

Unplugged/re plugged the USB cable for the pedals.

Reinstalled entire aircraft.

Turned off AccuFeel.

Set pedals to default in P3D.

Brakes still engage full when landing on the Lear.

What's up with this aircraft?

I'm running HF2 only if that makes a difference.

Thanks,

Mark

 

[ark 1,291]

26 minutes ago, newtie said:

Hi Al-

Here's what I've done so far.. Loaded a single prop Carenado, flew that brakes do not engage on landing.

Removed FSUIPC.

Unplugged/re plugged the USB cable for the pedals.

Reinstalled entire aircraft.

Turned off AccuFeel.

Set pedals to default in P3D.

Brakes still engage full when landing on the Lear.

What's up with this aircraft?

I'm running HF2 only if that makes a difference.

Thanks,

Mark

 

Hi Mark,

I doubt the problem is inherent to the aircraft. I have not been able to reproduce the problem in P3Dv5 HF2, and to date haven't seen any other reports similar to yours, so I think we need to try and figure out what's going on with your particular setup.

If you have any saved Lear35 flights I would delete them all.

If you activate the brakes in the air, do they say on?  And when you can, try the taxi experiments I outlined above using the . (period) key to see what happens.

And please clarify, when you land do the brakes engage totally by themselves, or is it that once you apply them they don't release until you stop and reapply them?

Edited August 23, 2020 by ark

[newtie 533]

Hi Al-

After testing for the last hour, this is my conclusion: On my system, when the Lear contacts the runway, the brakes apply themselves full of their own accord. When the Lear comes to a stop with the brakes applied of their own accord, the lower left red 'BRAKES' light goes out and the brakes function normally thereafter. This occurs at all airports tested. No other aircraft exhibits this behavior.

Testing

All assignments checked for duplicates.

Reverse boxes checked.

No Autobrake assignments.

A couple of saved flights deleted.

When on the runway for takeoff, run up to 20 knts, apply keyboard  '.' for braking. Red 'BRAKES' sign appears, both brakes apply simultaneously. Release '.' , light goes out.

Repeat, apply left toe brake (Saitek rudder/brake pedals), red 'Differential Brakes' appears, Lear pulls left as expected, same behavior for right pedal.

Checked .cfg file for any weird brake code, none except for info.

Removed Accusim completely, no change.

Something is triggering the brakes to engage full when contacting the runway.

There you have it

 

[ark 1,291]

1 hour ago, newtie said:

Something is triggering the brakes to engage full when contacting the runway.

Sure sounds like an autobrake activation that happens when there is weight on the wheels and throttles are at idle, but of course the Lear doesn't have autobrakes!  The next time you land and the brakes activate, push the throttles up as if doing a touch and go and see if the brakes release. You could also try landing with the throttles up somewhat to see if the brakes still automatically engage.

I see under key assignments there are options for autobrake increase/decrease. Worth making sure they didn't get assigned somehow.

If you have any other 3rd party addons like Chaseplane, etc., I'd temporarily disable them to see what happens just in case there is a weird conflict of some type.

BTW, when you reinstall the Lear, it is important to first uninstall the existing version and then delete any files left over in the install location to make sure nothing is carried over from the old install to the new one.

Do you have an other sims like FSX or P3Dv4 to try?

Al

 

 

Edited August 23, 2020 by ark

[newtie 533]

Did as you suggested regarding a go around/ bump throttle. No difference.

I removed all 'auto_brake' code from the aircraft.cfg.That fixed it.

I'll keep you updated regarding any weirdness this may cause over time. Might want to run this one by Mark.

Cheers and thanks much for your time and help,

The other Mark :>)

[ark 1,291]

4 hours ago, newtie said:

I removed all 'auto_brake' code from the aircraft.cfg.That fixed it.

'Other Mark'

Glad you got things working, but don't understand what autobrake code you removed from the aircraft.cfg. The only autobrake entries I have in the aircraft.cfg are the voltage and current requirements (auto_brakes  = 0, 5, 8.0) and the specification auto_brakes = 9 which means If the Lear had aurobrakes, the autobrake switch has 9 positions. But this is meaningless since the Lear doesn't have autobrakes or an autobrakes switch (at least my Lear35  doesn't 😉). The aircraft. cfg  doesn't really have code that gets executed, but rather has values that executing code in the Sim can access. So I still wonder what on your system is triggering the autobrake "like" code for the Lear?

Al

Edited August 23, 2020 by ark

[newtie 533]

I'm in the middle of KPDX > KSTS @ FL250

I'll let you know if I'm imagining things. :>)

Edited August 24, 2020 by newtie

[ark 1,291]

11 minutes ago, newtie said:

I'm in the middle of KPDX > KSTS @ FL250

I'll let you now if I'm imagining things. :>)

Have a good flight!  But when you can do let me know what you removed from the aircraft.cfg. I'd like to figure out what was happening if I can.

Al

Edited August 24, 2020 by ark

[newtie 533]

Just landed, no brake lights.

Perfect. Love it. i can fly my favorite jet again!

Code removed as follows:

auto_brakes        = 0, 5, 8.0
auto_brakes = 9

There ya go.

https://drive.google.com/file/d/1125Yj7OoxgxcLrWNlcXHtWkFfU4nQUIa/view?usp=sharing

[ark 1,291]

Well, it's still a mystery because I do not have to remove those two lines, nor have I heard of anyone else having to do so. And as you can see from my post above on what those values mean, it is hard to understand why it would make any difference.  But of course, if it solves your problem --  great!

Al

[ark 1,291]

3 hours ago, newtie said:

Just landed, no brake lights.

Hi Mark,

I did a little research and it turns out there is a connection between the real Lear's emergency brake system and the sim's autobrake system which clarifies things a bit, at least for me.

In the real Lear35, the emergency brake system is used to stop the aircraft if the regular brakes are inop due to some kind of failure, such as loss of hydraulic pressure. Pushing down on the red emergency brake knob releases high pressure nitrogen from a bottle to activate the brakes (btw, this same nitrogen is used for emergency gear extension as well).  The further the red knob is pushed down, the more pressure applied to the brakes, and the brake pedals and anti-skid system do not function with the red knob depressed.  Releasing the red knob back up cuts off the high pressure nitrogen and releases the brakes. So one can imagine in a real emergency pushing down on the red knob once the aircraft has touched down and continuing to do so until the aircraft has come to a safe stop.

To simulate the above in the sim with the Lear35, the sim's autobrake system is used.  You set ("push down") the emergency brake (red knob) while in the air on approach before landing and it activates when the wheels touch (as if a pilot had pushed down on the red knob), and can be released when the a/c stops.  I found that if I set the emergency brake before landing it does activate when the wheels touch and will not release with the normal brake pedals while the a/c is moving (although for some reason it does release if I push the '.' period key). 

So if you are having this happen every time then I suspect that something is setting your emergency brake. I would check the red knob position just before landing (assuming you have replaced the aircraft.cfg entries) to see if in fact it has become activated somehow, or maybe something is activating the sim's autobrake increase function in the sim's controls assignment tab. In any case, this explains why removing the auto_brake entries from the aircraft.cfg file "fixed" your brake activation on landing problem (although you are in big trouble if you lose hydraulics since you no longer have emergency brakes!  😉 ).

Al

Edited August 24, 2020 by ark