---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Fri 08/29/14: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:30 AM - Re: The cost/benefit ratio for automation (racerjerry) 2. 10:16 AM - Re: Battery bulge (Robert L. Nuckolls, III) 3. 10:54 AM - Re: Re: The cost/benefit ratio for automation (Robert L. Nuckolls, III) 4. 01:44 PM - Re: Re: The cost/benefit ratio for automation (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 05:30:25 AM PST US Subject: AeroElectric-List: Re: The cost/benefit ratio for automation From: "racerjerry" > I had been through the drill many times to simulate an engine out emergency but I know for me when it actually happened, I did not perform as well as I could/should have. After flying an ultralight for 300 hours, I was certain that I wanted to continue flying and bought an older 172 with hopes of quickly obtaining my private pilots license. Immediately, I proceeded to plaster any available blank panel space with cheat sheets or reminders and checklists to help me along. It worked well. Each list was laminated and stuck to the panel with a dab of Velcro so I could easily modify them as needed. Most of those early reminders have since disappeared, but many still remain. One list still worthy of retention is an ENGINE OUT CHECKLIST, because it is so little used, escapes memory and you usually dont have time to fiddle with the manual. -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=429571#429571 ________________________________ Message 2 _____________________________________ Time: 10:16:43 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Battery bulge At 12:00 PM 8/28/2014, you wrote: > >My comments to a friend started the recent battery thread on this >list. During an annual on my Glasair I noticed a bulge on the >firewall mounted battery which was three inches in diameter and >about 3/16 inches high. On the 'end' or 'broad-side'? >I replaced the battery with a new one, and after only one hour of >flight time the new battery developed a similar bulge. For fifteen >years I've followed Bob's advice to replace the battery every year, >and I've never had a problem until the last two batteries. They >were BatteryPlus (Weiker, 12v, 32 amphr, regular batteries, cost >about $80), but the last two batteries were "deep cycle". That's a really big battery for an airplane . . . what are your battery-only endurance targets? > The cooling air flow has not been altered; the 60 amp alternator > still produces 14.4 volts and the ammeter seems normal. Question: > could my problem be the "deep cycle" property of the last two > batteries? Thanks, Bob in Virginia. END Could be . . . do you still have them? Bob . . . ________________________________ Message 3 _____________________________________ Time: 10:54:17 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: The cost/benefit ratio for automation At 03:36 PM 8/28/2014, you wrote: > >I was wondering about automatic fire extinguishers and whether or >not this philosophy might be applied to them. Good question . . . for which there are no pat answers. One first needs to detect the presence of fire. Not an easy task. Worked on a fire detection system some years back that seemed pretty well thought out. The 'detector' was a length of what you might call semi-rigid coax. It was about 1/8" diameter. The dielectric material was a semi-conductor with a large temperature coefficient of resistance. A length of this 'cable' was routed about the engine compartment not unlike a piece of plumbing. The installer was encouraged to route into areas most likely to be a location for fire. Under normal ops, the TOTAL resistance of this 8-foot long resistor would assume some nominal value but if any portion of its length were exposed to flame, resistance in that area would drop sharply. The 'trick' was to detect that drop. With modern software, that task would be much easier . . . we did it with op-amps. This was a warning system . . . all it did was flash a light. We built a working prototype but got out-bid by another supplier . . . never got any history on the effectiveness of this technology. Numerous approaches have been devised for the detection of fire. Do a search on "fire detection" on http://www.freepatents.com for a sampling of the proposed technologies. I look back with fondness on the long-thermistor detection system for its simplicity. To be sure, there are lots of complex ways to watch for fire. The problem to be approached for the decision to automate is rooted in the complexities. A fire detection system brings new preventative maintenance issues . . . others come with risk for false warning. Depending on the fire suppression physics, the cleanup after dumping the bottles can range from benign to severe and all are no doubt expensive. One is further tasked with identifying the high risk sources for fire. In air transport category aircraft, the risks run all over the airplane with a constellation of potential events ranging from smoking in the john to lithium batteries in the hold to compromised wiring setting insulation on fire. In the OBAM aircraft, we're pretty much limited to fluid fed fires under the cowl. The idea that split-second decision to actuate the fire suppression system will somehow "save the day" doesn't offer much comfort. It's sorta like putting boots on the leading edges for ice-removal. Boots are useful over a very narrow range of circumstances . . . better to apply greater diligence in avoiding and/or escaping icing conditions. Similarly, one's return on investment for keeping fluids under the cowl properly contained will go a lot further to reducing risk than adding a fire suppression system - automated or not. It's much easier to prevent fire than to deal with it after it starts. Bob . . . ________________________________ Message 4 _____________________________________ Time: 01:44:24 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: The cost/benefit ratio for automation At 07:28 AM 8/29/2014, you wrote: > > > > I had been through the drill many times to > simulate an engine out emergency but I know for > me when it actually happened, I did not perform > as well as I could/should have. > > >After flying an ultralight for 300 hours, I was >certain that I wanted to continue flying and >bought an older 172 with hopes of quickly >obtaining my private pilots >license. Immediately, I proceeded to plaster >any available blank panel space with =98cheat >sheets=99 or reminders and checklists to help me >along. It worked well. Each list was laminated >and stuck to the panel with a dab of Velcro so I >could easily modify them as needed. Most of >those early reminders have since disappeared, >but many still remain. One list still worthy of >retention is an ENGINE OUT CHECKLIST, because it >is so little used, escapes memory and you >usually don=99t have time to fiddle with the manual. But how much is there to diagnose engine stoppage in a 172. One flies on BOTH tanks, BOTH mags and it's a gravity feed fuel system to the strainer sump. If the engine starts to fade, the elapsed time from when your hand starts to move toward the boost pump switch (while glancing at fuel pressure gage) is but a second or two . . . Emacs! That airplane is a fine example of risk reduction through simplicity. Short of catastrophic failures from which there is no engine recovery, likelihood of failure due to anything but dry tanks is vanishingly small. Critical systems management needs to be as automatic as the practiced flare looking for a greaser. This system offers not the slightest risk of needing to fiddle with the manual . . . or sift through post-it notes on the panel. Critical systems management needs to be as automatic as the practiced flare looking for a greaser. Bob . . . ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.