engine 5

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  • Mark replied to the topic Desktop Streaming in ADS-B Receivers
    Homepage stream display now using HTML5 format and should be viewable by all visitors.

    Month long battle to figure things out. VLC .... no help. Standalone encoder ..... no help. Finally found OBS as a steaming program. Paid subscription to Dacast .... success!
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  • Mark created a new forum post in ATA 32 Landing Gear
    As part of the ongoing troubleshooting of a brake temperature system with a long history of the right side brakes indicating 0's after landing, we tried to verify whether the problem was indication or actual brake actuation.

    For brake temperature problems, you normally want to meet the aircraft right after landing to check things out while the brakes are hot. (We finally accomplished that and a forum entry has been made..... https://rotate.aero/forum/troubleshooting-tips-general/340-thermocouples .)

    Referencing the above link, we did verify that the problem was with the braking system and not the indication.

    Previous to that though, I simulated brake temperature signals from the monitor unit to the EICAS system.



    I used a flashlight battery pack that had an output of about 1.2VDC.



    I fed this voltage into pins C10, C11, C12, C13, D9, D10, D11, and D12 of plug B at the monitor rack. The negative lead from the battery pack was connected to aircraft ground.



    With a 1.2VDC input, each brake indicated 2 on the EICAS system.



    767-300 SSM 32-46-01
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  • Mark created a new forum post in Troubleshooting Tips
    Thermocouples are used on aircraft to measure brake temperatures and engine EGT (Exhaust Gas Temperature). The heating of two dissimilar metals (Chromel and Alumel) creates a small DC millivolt signal. Higher voltages equate to higher temperatures.

    We had an aircraft (767-300) with a long history of the right strut brakes indicating "0" (with the left side brakes reading 1 or higher) after landing. The 767 doesn't show actual temps, just a scale 1-9.

    The absolute first thing to do with a brake temp split is to grab a laser temp gun and measure the brake rotors. If the measured temperatures match...... you have an indication problem. If the brake temps do not match...... you've got a control (application) problem.



    With this aircraft, the right strut brakes read in the mid 200's Fahrenheit. The left side brakes were over 600F. EICAS indication was 2 for all brakes on the left and 0 for the right.


    I found a cheap signal generator on Amazon for troubleshooting this problem.





    I wasn't sure if the damn thing would even work, but surprisingly it did. I simulated a 20Mv signal and fed that into the #7 brake sensor plug. I used the positive lead on the Chromel pin (1) and negative on the Alumel pin (3).




    We had a reading of 5 on EICAS. (A 10Mv signal gave us a 2.)




    This simulation, along with with the laser gun readings ruled out indication as the fault.

    I'm sure this simulation method will work with engine EGT indications also.
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