Mailing List flyrotary@lancaironline.net Message #28061
From: Todd Bartrim <haywire@telus.net>
Subject: EWP controller failsafe
Date: Fri, 2 Dec 2005 01:04:29 -0800
To: Rotary motors in aircraft (E-mail) <flyrotary@lancaironline.net>
My installation has 2 EWP's with the primary pump speed controlled by an electronic controller and the secondary pump controlled by an on/off switch. I had been concerned about the failure mode of this controller (fail on or off ?), so I'd wired a DPDT switch to the power input to the controller giving me auto/on positions on the switch. This would allow me to bypass the primary pump controller in case of a failure.
    Well once again in my infinite wisdom, and being cold and in a hurry to finish up a few minor details so we could go do a taxi test, I was installing a jumper to supply power for a new EBP switch reaching up behind the panel working by feel (hey it's hard enough to get under there without winter gear on) and for some dumbass, unexplained reason, not disconnecting power, when I suddenly inadvertently shorted my screwdriver to the hot jumper and the ground side of the EWP controller DPDT switch, Doh! Fuses blew, I cussed and replaced fuses and found the primary EWP to be pumping at full speed when stone cold engine temps. So apparently my EWP controller is T/U but failsafe is on, so this is good news. I'll remove the controller in the spring and try to isolate the blown component, but in the meantime can just fly with full primary EWP flow.
    Unfortunately @ -15C, full power climb could only produce engine temps of 140F. Descent temps would drop to <100F
I have a few other items to discuss from this flight, but I've gotta get some sleep right now.
 
Todd Bartrim    (suffering from 2 broken ribs due to hockey ;-(
 
RV9Endurance
13B Turbo Rotary
C-FSTB
 
             "The world will always have a place for those that bring hard work and determination to the things they do."
 
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster