I can find no place in the 'Captain Sim'  FLIGHT MANUAL PART II - Aircraft Systems where brake temperature is addressed. The brake temperature is accessed by left clicking the mouse when it is over the status switch on the forward aisle stand control panel. Brake temperature will then appear in the secondary EICAS display. The temperature is always 0 no matter if the plane is on the ground prior to flight, in-flight, or just completed a rollout after a landing. Unless someone has an answer I will assume this is one the many pieces of eye candy on the allegedly "realistic" 752.

If version 4.5 is no better than 4.4 this plane's last flight will be to Victorville CA to join the 762 and 763 to disintegrate in the desert sun.

Michael Cubine

DAL191 wrote on Sep 11^th, 2011 at 2:51am:

If version 4.5 is no better than 4.4 this plane's last flight will be to Victorville CA to join the 762 and 763 to disintegrate in the desert sun.

Depressing.

But! The brake temperature does work, I have seen the temperature at around 4 for all of the brakes. It occurred after landing with the autobrakes engaged.

NNewcomb wrote on Sep 11^th, 2011 at 3:16am:

DAL191 wrote on Sep 11th, 2011 at 2:51am: If version 4.5 is no better than 4.4 this plane's last flight will be to Victorville CA to join the 762 and 763 to disintegrate in the desert sun. Depressing. But! The brake temperature does work, I have seen the temperature at around 4 for all of the brakes. It occurred after landing with the autobrakes engaged.

NNewcomb

Do you remember what the autobrakes were set at?  I always use 2. For this test I used 4.

Michael Cubine

NNewcomb wrote on Sep 11^th, 2011 at 3:16am:

But! The brake temperature does work, I have seen the temperature at around 4 for all of the brakes. It occurred after landing with the autobrakes engaged.

I'll back him up because I've seen the temperatures get to about 4 as well. When using the autobrakes on landing. ;)

DAL191 wrote on Sep 11^th, 2011 at 5:35am:

NNewcomb Do you remember what the autobrakes were set at?  I always use 2. For this test I used 4.

I usually set them to about 3-4 depending on the length of the runway. I never use lower than 3.

I got a 757 DVD and the captain on that one said that the brake temperature scale goes from 0 to 9. 3 or 4 is normal after a fairly heavy brake after landing, it basically never goes to 9, unless the brakes are on fire and are about to fail.

To NNewcomb, Mark and wims:

Thanks for the information.

Michael Cubine

I tried a test flight with maximum payload and about 13500 lbs of fuel to replicate the landing condition of 752 after a flight. I set the autobrakes to MAX, flaps at 20, spoilers armed, no reverse thrust, and landed. Essentially it put a tremendous load on the brakes. The temperaure was 8. I guess at 75-80% payload, 25 flaps, reverse thrust, and autobrakes at 2 the brakes did not work hard enough to register on the scale wims mentioned.

It would be nice if if the autobrakes temperature was mentioned in the manual. With no mention I didn't know whether to look for the real temperature or a scale. I have planes that do one or the other.
Thank you
Michael Cubine

I just did a flight and had the brakes on my 757-200 reach [3] using Autobrakes setting 2.
My aircraft weight was not very heavy either. I think I had 10,000 lbs of fuel and a 33,500 lbs payload. Total weight would have been approximately 186,000 lbs. My settings were 20% flaps V^ref of about 130 knots. Because I landed at V^ref+10 I landed at about 140 knots.
I used Fraps to make a video of the landing. I'll see if I can get it up on YouTube, but I have had trouble uploading at times.

Mark

Markoz wrote on Sep 12^th, 2011 at 2:29pm:

I just did a flight and had the brakes on my 757-200 reach [3] using Autobrakes setting 2. My aircraft weight was not very heavy either. I think I had 10,000 lbs of fuel and a 33,500 lbs payload. Total weight would have been approximately 186,000 lbs. My settings were 20% flaps Vref of about 130 knots. Because I landed at Vref+10 I landed at about 140 knots. I used Fraps to make a video of the landing. I'll see if I can get it up on YouTube, but I have had trouble uploading at times. Mark

Let me know if you succeed in uploading the video. I would like to see it.

Michael Cubine

Hi Michael.

I got it uploaded without any difficulties for a change. ;D

http://www.youtube.com/watch?v=AKTrkacxXV8

Mark

Mark

The video looks good. Do you know what the red message below TCAS FAIL on the Secondary ECAS at about 1:39 of the video is?

Thank you
Michael Cubine

The TCAS FAIL light always comes ON when the 757 is on the ground and the TCAS is set to TA ONLY or TA/RA.

Mark

Quote:

red message below TCAS FAIL

I think he refers to the Autopilot Disconnect, Mark. You are using the Disco Bar there, so that triggers the message.
But you are darn fast, so it wasn't up for long.  :D


I think the brake temp display implementation is a bit confusing. Without having the tech docs there, I'd say that on braking, the temps (from the energy being converted into heat) go 'into the brakes' and later reach the sensors.
This means that, on landing ,you will mainly see zero impact on that display but on taxi to the gate and after e. g. parking there for 10 minutes, the heat will have built up and also reach the sensors then.

So, at the parking after 10 to 15 minutes, the temp display should give you the highest readings with a slow decrease through brake fans and stuff later.
Maybe they can tune this in 4.5 since your temps got up on the actual brake activation and got down as the auto-brake released the pressure.
I think that this doesn't reflect the rw brake temp monitor's behaviour as the readings are instantaneous right now and also fade away right after braking.


I always brake with the grass strip behind the runway.
http://img339.imageshack.us/img339/8638/cimg0905ha.jpg
It's all about brake wear, buddy.

CoolP wrote on Sep 16^th, 2011 at 4:25am:

Quote: red message below TCAS FAIL I think he refers to the Autopilot Disconnect, Mark. You are using the Disco Bar there, so that triggers the message. But you are darn fast, so it wasn't up for long.  :D

Oops. I misread Michael's question! Sorry Michael. :( Yeah. It is the AUTOPILOT DISC like CoolP says. Thanks CoolP.

Mark

CoolP is correct - There is a time lag until the temps register on the display.

In the RW, we always use full flaps for landing & final speed of bug + 5 unless there is an ad for wind.
Using less than full flaps makes for a longer roll out and more brake wear.
The rule for auto brakes was - CAT-II brakes 2, CAT-III brakes 3.
Using max braking was a pretty violent thing to do to the plane.
Remember, for every extra knot Boeing says it takes another 50 feet to stop!

Lou