FastEddieB Posted January 25, 2014 Report Share Posted January 25, 2014 I think we can all point to times we’ve had momentary lapses of attention. Hopefully, most times the consequences are minor or just irritating. But think of some of the recent lapses discussed here and elsewhere: A professional Asiana airline crew with a momentary lapse involving auto throttles crashing short of the runway. Two professional crews with a momentary lapse landing at the wrong airports. Two CT’s with low fuel emergencies, one which crashed and one which came perilously close to doing so. At a Cirrus “Critical Decision Making” seminar, they played a video showing a momentary lapse of an amphibious seaplane pilot, putting the gear down instead of up for a water landing. With results almost more tragic than one can imagine. And finally, the ValueJet Everglades crash was caused by mislabeled oxygen canister - someone obviously had a momentary lapse somewhere - and a LOT of people died. I had a major one in the past, involving an unlatched canopy on my Sky Arrow, which could have had dire consequences - but fortunately didn’t. The longer most of us fly, the longer the list of momentary lapses grows. There may exist a pilot who never, ever makes mistakes, but I have not yet found him or her. Checklists help, as do copilots or mechanics to check your work. How does this involve me right now? I had a momentary lapse which I thought I’d chronicle here as a possible warning for others. Last Wednesday, I made a trip to my (very cold) hangar with two new purchases in hand - a newly purchased Whelen LED landing light and a new Aerovoltz Lithium Iron battery. I was really looking forward to making two minor improvements to my Sky Arrow. Especially the battery, which would buy me about 12 or 13 extra pounds of valuable useful load. I had fun with the LED install, even taking time to set up a rig to compare the new lamp and the old. Job well done, if I do say so myself. Then it was time to see if the Aerovoltz would fit conveniently in the existing battery bracket. Good news - it was not as wide as I thought and wedged right in there, though I would have to come up with a spacer arrangement before testing it in flight. I also made note that the terminals were reversed, something to be aware of but not a problem since both battery cables seemed to have plenty of reach. Hooked up the cables, made sure both terminals were protected, snugged everything down and turned on the BATT switch. New landing light performed as promised, and everything seemed fine. But looking at the install more critically, I was not completely pleased with the “run” of the positive cable. It was about 1” away from the allen bolt that controls my nosegear friction. It looked easy enough to run both cables on the other side of a wiring bundle to give more clearance, and seemed the prudent thing to do. So I unhooked both cables, rerouted them, attached them and tywrapped them in their new location. Went around and turned on the BATT switch to confirm the connections and… …instead of everything coming to life, there was a quick hissing/pop sound. As quickly as I could I turned the switch off, and noticed a slight burning electrical smell. You can’t imagine the sinking feeling I had when I looked at the battery and discovered I had hooked up the cables in their old orientation. Which, unfortunately, fed reverse current into my electrical system when I threw the switch. That feeling was a combination of disgust and anger and disappointment in myself. I felt in my gut. I am NOT the kind of person to hook a battery up backwards. I check always check polarity and then check it again. If someone else was relating this account, I’d roll my eyes and think that that could never happen to me - I’m too careful. So, what happened? The first hookup was done with utmost caution for anything that could go wrong - including the new orientation of the terminals, routing the wires, protecting the terminals, all of that. On the second, I guess I was just coasting, on “automatic” as it were, and when it came time to hook up the terminals I did them just as I always had. Looked perfectly normal. Unfortunately, in this case it was backwards. Anyway, here’s the final install, before spacers and after the cables were reoriented properly: You can see the allen bolt I was getting clearance from by going outside of the existing wire bundle. It reminded be just a little bit of a very mild version of what Robert Pirsig, in “Zen and the Art of Motorcycle Maintenance” called a “Gumption Trap”. What’s a Gumption Trap? It’s best illustrated by a fictional, but all too possible scenario: Imagine you’re setting the blade angles as you reinstall a Warp Drive propeller. You install the prop bolts lightly, and back off on the clamp bolts a little. You use your tape measure to ensure each blade is in exactly the same position, and use your protractor device to set each blade just so. You tighten everything up incrementally with your torque wrench in stages, then do a textbook job of safety wiring the prop bolts. Finally, you reinstall the spinner with just the right dab of blue Loctite on each screw, and stand back and gaze upon a job well done. As you’re putting your tools away, you stumble upon the 1/8” spacer that’s required between the prop and the engine on your installation. Drat! Now its all got to come completely apart and be redone. This is where the Gumption Trap can rear its ugly head. Typically you’ll be somewhat annoyed and kind of rush into redoing something you’ve JUST done - and rarely with the patience and care you took the first time. The cure is to step away - go home, relax, have a drink, whatever. But regardless, come back to the project when you’re fresh, not aggravated. Don’t fall into the Gumption Trap! My case was not exactly like that, since I was in no way annoyed at having to reroute the wires - I was kind of proud of myself for having the foresight to envision a possible problem and deal with it, getting it “just so”. But there’s no doubt I wasn’t really giving it 100% of my attention. The dreaded “momentary lapse” mentioned above. As an aside, a fellow EAA member and friend was helping me with some stuff you’ll find in my first epilogue, to follow. I explained how this was embarrassing as I was NOT the kind of person to pull such a doofus mistake. He said he felt exactly the same way about ever running out of fuel - he was NOT the kind of person to ever pull a bonehead stunt like that. Until he did, and had to ditch with his wife in the Atlantic Ocean off the Florida coast. Made me feel a little better, I suppose. But not much. To be continued… Link to comment Share on other sites More sharing options...
FastEddieB Posted January 25, 2014 Author Report Share Posted January 25, 2014 Epilogue #1... Well, after the sick feeling I got from hooking the battery up backwards, there was nothing to do other than hook it up the right way and assess the damage. First thing that I noticed was that the flap breaker had popped - it was the only one that had. Popped it back in and the flaps worked - whew! Went through everything electric I could think of - strobes, nav lights, trim, panel lights, fuel pump, Dynon, 496, radio, etc., and everything seemed to be working. Except… The Garmin GTX327 transponder would not come on. I pulled it with my friend and we found a 5A fuse blown on the circuit board. Unfortunately soldered on. Called Garmin, they said it was a field serviceable part ($1) if that was all it was. Called Horizon Avionics in Knoxville and they said they’d be happy to look at it. They asked about the encoder, which had not crossed my mind, and suggested pulling that and bringing it in at the same time. I’m planning to do so one day next week. If the transponder does have to go back to Garmin, it’s something like a $575 flat rate repair. I initially could not hear audio from my radio. Noticed I could when I switched the intercom off (neither squelch nor volume had any effect). It’s a Sigtronics and I sent it back to them yesterday. Repair cost is capped at $69 plus return shipping if the unit can be saved, which they thought it could. If it’s toast (and it did have a burned electric smell) then a new one is around $279. I’m really hoping that’s all that was damaged. Things with switches that were switched off should have been protected, and I’m pretty sure I only turned on the BATT side so the Alternator and hopefully the voltage regulator should be OK. I hope. Oh well, it is what it is and compared to some of the tragedies that I listed in the initial post, this will over time fade into insignificance and go down as a learning experience. It’s only money. More as it develops… Link to comment Share on other sites More sharing options...
FlyingMonkey Posted January 25, 2014 Report Share Posted January 25, 2014 Sorry to hear this Eddie, I hope you get it all sorted out will minimal damage to your wallet. At least it was a problem that showed up on the ground and not in the air. I'm guessing you must have flipped the master on, to have any damage at all to your Xpdr and intercom? Link to comment Share on other sites More sharing options...
Runtoeat Posted January 25, 2014 Report Share Posted January 25, 2014 Eddie and MovingOn, thanks for 'fessin' up to some mistakes. I've been there and done that with jumper cables and suspect many others who read this post have too. The list of "other bone head mistakes" I've made is too long to delve into here. It's good to be reminded to slow down, take a few extra deep breaths and when returning to the task, avoid the "gumption trap". If these reminders happen often enough, perhaps they might cause us to better reflect on what's at hand and help in delaying or eliminating our "next mistake". As for me, I'd like to think I'll be mistake free but I know better. Link to comment Share on other sites More sharing options...
CT4ME Posted January 26, 2014 Report Share Posted January 26, 2014 'Great information... I'm going to try and identify these buggers and eliminate as many as possible. tim Link to comment Share on other sites More sharing options...
2FlyAgain Posted January 26, 2014 Report Share Posted January 26, 2014 I read Pirsig's book many years ago. I don't know if I even caught the reference to the "gumption trap". Thanks for the reminder particularly in this context. Some thing else along this line for me is transition from rental pilot to owner. As a rental pilot one of my motivations for checklist usage was the fear of how the previous pilot left the plane. Just because I know that I am the last person to fly the plane, doesn't mean the last person to fly the plane left it in "perfect" condition...or that it has stayed in perfect condition since the last time that I flew it. Link to comment Share on other sites More sharing options...
opticsguy Posted January 26, 2014 Report Share Posted January 26, 2014 I was so happy to get my CT started with a new battery I forgot that I had half the radiator covered from my last flight in the low 40s. It was 60 degrees at 2500 ft and I had a high CHT alarm go off (247F) on climb-out after a TnG. Oops. Had to take my time getting home. If I could find a way to cover my oil-cooler and not the radiator at the same time, that would be ideal. Link to comment Share on other sites More sharing options...
mocfly Posted January 26, 2014 Report Share Posted January 26, 2014 Opticsguy, The way you do that is to split the radiator and cooler. Then reconfigure the assembly and attachment points per FD. You would then be able to blank off part of the cooler. The other option to try is blanking off the back off the oil cooler and not the front of the assembly sandwich. There will be enough air to keep the heads cools and enough of a restriction to keep the oil temp elevated. This configuration definitely requires that you use a piece of aluminum and that it be fixed in such a way that provides easy removal and enough security that it will not come loose in flight. Good luck.. Let's us know how you make out Link to comment Share on other sites More sharing options...
opticsguy Posted January 26, 2014 Report Share Posted January 26, 2014 I guess I'll stick with my fine tuning of tape vs temperature. It least I have a cool running engine, so I don't have issues in the TX summers. But if it's under 80F, my oil doesn't warm up while flying. Link to comment Share on other sites More sharing options...
Jacques Posted January 27, 2014 Report Share Posted January 27, 2014 The other option to try is blanking off the back off the oil cooler and not the front of the assembly sandwich. There will be enough air to keep the heads cools and enough of a restriction to keep the oil temp elevated. This configuration definitely requires that you use a piece of aluminum and that it be fixed in such a way that provides easy removal and enough security that it will not come loose in flight. exactly what I did,, a strip of velcro each side of the back of the oil cooler and a piece a aluminum Link to comment Share on other sites More sharing options...
Jim Posted January 27, 2014 Report Share Posted January 27, 2014 Being an electronics engineer and having done the equivalent of Eddie's screwup several time the last 40 years, I am religious about checking polarity. As to flying, having the passenger door fly open during runup tought me to checklist and check "pax door locked". And that getting caught "VFR over the top" with no place to get down will cause a bad day. Link to comment Share on other sites More sharing options...
FastEddieB Posted January 27, 2014 Author Report Share Posted January 27, 2014 ...I am religious about checking polarity. Me, too! But I guess even the devoutly religious have occasional lapses. That's what confession is about, right? Link to comment Share on other sites More sharing options...
FlyingMonkey Posted January 27, 2014 Report Share Posted January 27, 2014 As to flying, having the passenger door fly open during runup tought me to checklist and check "pax door locked". And that getting caught "VFR over the top" with no place to get down will cause a bad day. After a friend lost a CTSW baggage door when a student left it insufficiently latched to the replacement tune of $1180, I started getting very conscientious about this stuff. I bump check both baggage doors before engine start, and when I get to the checklist item for doors latched I both ask the pax if the door is latched AND reach across them and push on the door to make sure. Do this when alone too (except the asking part, don't talk to myself there). Takes 3 seconds and adds to my peace of mind. Link to comment Share on other sites More sharing options...
FlyingMonkey Posted January 27, 2014 Report Share Posted January 27, 2014 exactly what I did,, a strip of velcro each side of the back of the oil cooler and a piece a aluminum That velcro adhesive doesn't get hot and run off or lose its "stick"? Link to comment Share on other sites More sharing options...
Jacques Posted January 27, 2014 Report Share Posted January 27, 2014 That velcro adhesive doesn't get hot and run off or lose its "stick"? the picture is after ~ 50 hours...so far so good Link to comment Share on other sites More sharing options...
FlyingMonkey Posted January 27, 2014 Report Share Posted January 27, 2014 the picture is after ~ 50 hours...so far so good Do you have different sizes of back plates, or do you just always use the full sized plate? You are in Canada, so temps up there probably call for the full plate half the year or more. Link to comment Share on other sites More sharing options...
Jacques Posted January 27, 2014 Report Share Posted January 27, 2014 Do you have different sizes of back plates, yep,, just this one ..most of the time I have the ''100 hp oil cooler''... but the 80 hp engine....so..running too cool most of the time I'm installing the 100 hp right now.. and will probably have to remove the plate in the summer also installing a different thermostat with higher opening temp. all that without getting in any Gumption Trap...hopefully Link to comment Share on other sites More sharing options...
opticsguy Posted January 28, 2014 Report Share Posted January 28, 2014 I'll have to try that with some clamps. My oil cooler is so thoroughly covered with greas that I'll never get that Velcro to stick. I know for a fact that Velcro adhesive gets soft at about 140F, so a mechanical attachment will be required. Link to comment Share on other sites More sharing options...
FastEddieB Posted February 2, 2014 Author Report Share Posted February 2, 2014 Epilogue #2: 1) Got a message from Sigtronics. I was prepared for the worst, but when I called back they said the damage was a little too extensive to fit into the usual $69 maximum repair. Good news is they can still do it for $80 to $90, and say it will be as good as new. Whew! 2) The encoder was ridiculously easy to pull, and yesterday we dropped off the transponder and encoder at TACAir in Knoxville for Horizon Avionics to pick up tomorrow morning. I'll report back the findings. This too shall pass... Link to comment Share on other sites More sharing options...
Anticept Posted February 3, 2014 Report Share Posted February 3, 2014 and yesterday we dropped off the transponder I missed the word "off" and thought you said you dropped your transponder... I was going to say! Link to comment Share on other sites More sharing options...
FastEddieB Posted February 3, 2014 Author Report Share Posted February 3, 2014 I missed the word "off" and thought you said you dropped your transponder... I was going to say! At this point, it would not surprise me! Link to comment Share on other sites More sharing options...
Runtoeat Posted February 3, 2014 Report Share Posted February 3, 2014 Eddie, you've provided the key phrase here; "this too shall pass". This elicits a question for our resident wire wizzards. Would it be possible to put a diode inline on the neg. battery cable to prevent sending reversed current to our equipment, in the event the cables are crossed? Or, if not practical on the battery cable, perhaps a diode at the power cables to our sensitive and expensive-to-fix equipment. Link to comment Share on other sites More sharing options...
FastEddieB Posted February 3, 2014 Author Report Share Posted February 3, 2014 Maybe even more elegant would be to make the cable connections such that one could not physically hook them up wrong. I think FD did that as a fix to hooking up the "lanes" wrong on the CTLSi. But going to a new battery type or style would probably defeat that attempt anyway. Try to make something idiot proof and they just invent bigger idiots! (Present company excepted, of course!) Link to comment Share on other sites More sharing options...
Anticept Posted February 3, 2014 Report Share Posted February 3, 2014 Eddie, you've provided the key phrase here; "this too shall pass". This elicits a question for our resident wire wizzards. Would it be possible to put a diode inline on the neg. battery cable to prevent sending reversed current to our equipment, in the event the cables are crossed? Or, if not practical on the battery cable, perhaps a diode at the power cables to our sensitive and expensive-to-fix equipment. A diode which can carry 20+ amps would be massive and inefficient. just color the wires so it's obvious how it should be hooked up. If it's really vital, hook up an LED in reverse bias. If you hook it up wrong, it will light up, letting you know. It's the simplest design I can think of without using things like solenoids (just another failure point), or big inefficient diodes. Link to comment Share on other sites More sharing options...
Runtoeat Posted February 3, 2014 Report Share Posted February 3, 2014 "Big inefficient diodes" is why I also offered an option to install small diodes on power supplies to sensitive/costly equipment. The LED would work if one didn't already have some equipment "on" when the cables were attached. Red LED "on" = lotsa smoke! Link to comment Share on other sites More sharing options...
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