Community Fri, 17 Aug 2018 12:43:54 +0000 MYOB en-gb Mark
]]> (Mark) story Tue, 07 Aug 2018 18:23:40 +0000
Mark created a new forum post in ATA 25 - Equipment/Furnishings
Hawker 900EX with the left equipment cooling fan indicated as failed.

With the multifunction displays removed, there was a large amount of air coming from the piccolo tube located below the display racks.

With the lower side-wall pulled off, it could be seen that the air from the cooling fan was split into three user systems. The large tube going to an adjustable vent for the crew (L/H vent), the mid-sized tube going to the multifunction displays, and the small tube routed to the glare-shield.

The weird issue with this particular failure was that the fan output was strong. We could clear the failure by just opening up the crew adjustable vent. With the vent closed, the failure would reappear. Corresponding air flow from both the other outlets would increase with the pilot vent closed. All functions seemed perfectly normal.

The flow sensor is actually part of the fan assembly. It doesn't sense air flow, it senses fan speed. With our one vent closed, the flow was restricted enough to slow the fan down and set off the warning. The funny thing was, the air flow from the failed system was twice as strong as the R/H side which had no failures at all.

The fan assembly is below the floor, just outboard of the control yoke column.

Fan (only the sensor wiring can be seen from this angle).

Hawker 900XP WDM 25-10-12-01
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]]> (Mark) kunena Mon, 06 Aug 2018 23:32:41 +0000
Mark replied to the topic Pitot Heat in ATA 30 Ice and Rain Protection
I just don't understand how the "trons" flow. There's no hard ground in the system when they're in the air..
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]]> (Mark) kunena Wed, 01 Aug 2018 22:34:53 +0000
jake ounce replied to the topic Pitot Heat in ATA 30 Ice and Rain Protection
I'd bet the Window Heat Controllers have logic that figures this out and provides a path.
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]]> (jake ounce) kunena Wed, 01 Aug 2018 21:53:14 +0000
Mark replied to the topic ATA 32-31, Gear Control in ATA 32 Landing Gear
Main gear down cycle.

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]]> (Mark) kunena Sun, 22 Jul 2018 14:37:13 +0000