ATR prop brake can be activated without hydraulic power

:wave: Thank you for using the Bug section, using templates provided will greatly help the team reproducing the issue and ease the process of fixing it.

2 tags are required: One for platform, and one for aircraft.

Are you using Developer Mode or made changes in it?

no

Have you disabled/removed all your mods and addons? If the issue still occurs with no mods and add-ons, please continue to report your issue. If not, please move this post to the Community Support section.

yes

Which aircraft are you reporting an issue about? (Please also add the proper tag for it)

ATR 42/72

Which aircraft version are you experiencing this issue on? (You can find this listed in the Content Manager under the Aircraft Name)

v1.0.36

Brief description of the issue:

According to ATR FCTMto activate the prop brake during startup, if it is not already illuminated blue, the HUD AUX PUMB BT has to be pressed. Ready will then light up in green and prop brake can be activated.
The issue is, in the current state the prop brake can be activated by just flipping the switch without any blue hydrolic pressure. It will immediately light up in blue. As far as I understand it, this is not how it should work.

This is the same issue described here:

Provide Screenshot(s)/video(s) of the issue encountered:

Imgur
Imgur
Imgur

Detailed steps to reproduce the issue encountered:

start at the gate, do the usual cockpit preparations, flip the PROP BRAKE switch to on. PROP BRK will illuminate blue without any hyd pressure or a green ready sign.


:loudspeaker: For anyone who wants to contribute on this issue, Click on the button below to use this template:

Do you have the same issue if you follow the OP’s steps to reproduce it?

Provide extra information to complete the original description of the issue:

If relevant, provide additional screenshots/video:

I have to retrieve the source info, however I’ve read the running Engine #1 allow hydraulic pressure to be used for Prop brake

At least here, however I have to retrieve my initial read :

[EDIT] Found !!!

Well, that is the point of my post. At the moment it can be engaged without any engine running.

Just try it. Activate the battery and then switch the flip. You will see it will get activated without any hydraulic pressure available.

Perhaps enabling ACW EXT PWR in the EFB will fulfill some conditions ?! No idea, though … I will check in any case in a few minutes, time to start the sim …

[EDIT] One point is the auxiliary pump seems on DC, which potentially doesn’t prevent operating it without engine running theoretically, with just BAT ON … should perhaps be allowed within the 30 seconds (just assumption here, not knowing the aircraft in any case)

I just tried this and from cold and dark with just BAT and DC GND POWER enabled you can start hotel mode/prop brake on ENG 2 with no HYD AUX PUMP being used. I don’t think that is correct. You don’t even see a green ready light (presumably because there is no hydraulic power). But it hotel mode/prop brake function starts non the less. No AC connected here, no ENG 1 start first. Just as described.
It’s also different from shutdown method which does seem to need HYD AUX PUMP after shutting down ENG1 then trying to start hotel mode.

I confirm :+1:

So, start situation …

BAT ON / PROP BRK is OFF with DC EXT PWR and ACW EXT PWR inactive on EFB :

image

PROP BRK is OFF :

image

Switch flipped : PROP BRK is ON

image

For Ref only : PROP BRK seems linked to AUX PUMP (as mentioned : on DC)
No statement here !

image

Just in any case, tried to operate PROP BRK switch outside the 30 seconds and PRP BRK is still ON, which may make sense though …

AUX PUMP isn’t on LO PR, however the STEERING TILLER isn’t rotating, as it should, as linked to the AUX PUMP too … this tend to prove there’s indeed currently an issue on the PROP BRK handling :thinking:

Not changed with 10/10 update. Still able to activate prop brake without any hydraulic pressure.