KR> Mailings
On 7/16/2014 3:42 PM, Mark Langford via KRnet wrote: > Ken Henderson wrote: > >> Lately my receiving of KRNet has been very spotty. I get every other >> one then it will skip 10 issues or so and start again. Anybody else >> having these problems? >> Also, last issue of Corvaircraft was received on 4/5/2013, Vol. 342 >> Issue 71. Attempts to contact Corvaircraft site only gets me ?Mail >> Delivery Failure? notices. Does anyone have any info about this? > > I've never heard of anybody missing so many issues of the digest, > especially not on this incarnation of the list. I will ask the folks > that run the email server if they have visibility into that.I'm > not sure if the numbering of the digests would have gone > non-sequential like that though. I'm posting this to the whole list to > see if anybody else on the digest has insight into this, or has a > similar problem, but if so, please send directly to me rather than the > whole list. > Mark, I have had no trouble receiving anything from the KR List, ever. Thank you for you efforts to keep it going, Virg
KR> Gathering
Hey Steve, I did finally register and I am looking forward to coming out to Chino. My only other trip in that area was a 5 hour layover in L.A. So, this will be all new. Just saw the agenda as to what you have proposed for the Gathering. I have several comments. 1. Thank you for making most of the seminars "hands on". I find those so much more informative and useful than a lecture. Please let me know what the cost of the materials will be for the seminars. I don't expect you guys to actually have to buy materials for me to have and I intend to attend all of them. So to be clear, this means I will be leaving with an actual grounding buss that is designed specifically for the KR2S and that I can just bolt into my project? 2. As for the fiberglassing seminar, I still consider myself a newbie but I have been doing some glassing on a 66' Corvair coupe. And I have been surprised at how easy it is and how well it has worked out. Of course, it's for a car so I didn't care about weight. So I look forward to learning how to fiberglass properly on my KR2S. And I know all of my supplies have not been cheap but that's probably because I wasted a lot. hopefully you'll show me how to stop doing that. 3. The tour Saturday morning should be a blast. Very much look forward to that. Will there be enough seats to accommodate people who fly in via Southwest? Can you see if the local FBO might make you a deal on a rental and you just charge anybody interested (I am) what the seat costs? if not, are there two other guys coming who might want to split a rental with me? 4. I even really want to make my own antenna. And I can take it home with me and use it? Too cool. No offense to Larry, but this might be the best Gathering I've attended. And I'm sending this to the KRnet because of the following. May I make a suggestion? I've been to four separate Corvair colleges and I have had a great time at all of them. They were all hands on all the time. Even when all I did was help someone else I still had fun - getting experience and knowledge. One of the things they did was have a fee up front for whatever the costs were - primarily food. All the other stuff WW just sold flat out. And I sure you will be selling whatever items you carry to whoever wants them. At least it'll save the shipping cost. And in looking at what you are proposing, I know there is a cost for the materials you will need to buy that you will be giving out. I don't have a problem paying for that but I didn't see the fee anywhere. However, I do ask that you consider setting up the breakfast and lunches as part of the cost just like at the Corvair colleges. That way no one doesn't have to really stop what they're doing. No one will have to leave the hangar, the airport (is there an onsite restaurant close by?) or anything else. The group can stay together and keep working/learning the whole time. Nothing elaborate; Donut/danish breakfast, hamburger/hotdog lunch. Dinner will be our chance to check out the town. But very importantly, please make sure you have some nice area for after hours relaxation and conversation (Mount Vernon was great). So set up some kind of paypal thing - you probably already have that with NVaero and let me know what the fee is. At least for the materials. Just like WW, all I expect from you is your knowledge and experience. Personally, I would prefer to add the food in as well. It would save me time from having to go somewhere for breakfast and lunch - I hope everybody else registering agrees. Let me know. Thanks. Ray_pilot New Orleans
KR> Mailings
Ken Henderson wrote: > Lately my receiving of KRNet has been very spotty. I get every other one > then it will skip 10 issues or so and start again. Anybody else having > these problems? > Also, last issue of Corvaircraft was received on 4/5/2013, Vol. 342 Issue > 71. Attempts to contact Corvaircraft site only gets me ?Mail Delivery > Failure? notices. Does anyone have any info about this? I've never heard of anybody missing so many issues of the digest, especially not on this incarnation of the list. I will ask the folks that run the email server if they have visibility into that.I'm not sure if the numbering of the digests would have gone non-sequential like that though. I'm posting this to the whole list to see if anybody else on the digest has insight into this, or has a similar problem, but if so, please send directly to me rather than the whole list. Missing emails are most often caused by over-active spam filters, either your computer's or your ISP's, although one would think they would screen them all, not just some of them. It does happen though. You were not even subscribed to the CorvAircraft list, so I subscribed you, but be advised that it has been slow lately. Some days there are no posts at all. I guess the CorvAircraft world is pretty stable now...everybody knows how to do it so few questions are being asked. Feel free to pipe up with questions though, if you have them... Mark Langford ML at N56ML.com website at http://www.N56ML.com
KR> "Engine-driven alternator?"
In practice, the requirements for transponders are interpreted variously by different responsible agencies. In my TCA, surrounding SEA, the outer edges of the mode C skirt are largely unregulated in practice. If ATC cannot image you on radar, they do not want you pinging, nor do they want you talking to them. The wording in the FARs allows for an exception if prior permission is granted for operation without mode C ...this is assumed to have been granted for the entire S. Puget sound, and they don't want you calling them and asking. "Stay below radar coverage and keep VFR separation, I've got to deal with all of this heavy traffic, and OLY and McCord AFB will ignore you too in VFR conditions." In the LA TCA I've lost radio while asking for clearance into Ventura.( alternator was sparking and RFI overwhelmed the transmitter) In practice, I just turned toward White field (uncontrolled) and landed. All of this regulation is designed to allow ATC to provide positive separation where conflict is present. If they can't hear or see you, they want you to take care of yourself, whether your TC shows a source of electrical power or not. Peter
KR> "Engine-driven alternator?"
The Compufire electronic ignition on my 2180 VW from Great Plains uses 0.6 to 7.9 amps, idle to wide open throttle, as displayed on my instrument panel ammeter. The more sparks it makes, the more juice it takes. Sid Wood Tri-gear KR-2 N6242 Mechanicsville, MD, USA -- > > The idea of a high-tech battery sounds interesting, but I wouldn't be > needing it just for the avionics but also for the engine. I plan to have a > regular VW engine, probably Great Plains, and they normally have one > magneto, plus a secondary ignition that's powered by the alternator. So > either I'd have to fly on one magneto or have a battery system that's able > to put out enough juice to run a VW secondary ignition system for a whole > day's flying. Maybe a lithium battery could do that, but I'm not even > sure > how much juice a VW ignition system uses (or where to find that out). > > > > > Mike Taglieri >
KR> "Engine-driven alternator?"
Thanks for all the replies, though I guess I wasn't completely clear about the situation. You can't just go without an alternator just until you get out of the Mode C airspace. The FAA rule that lets you have a plane without ADS -B (or even a transponder, actually) is for planes that NEVER had an engine-drive alternator from the day they got their airworthiness certificate up to the present. The plane has to have lived a totally alternator-free life. That's why I was wondering whether "engine-driven" meant the big engine in the front or any kind of engine. If an alternator driven by some smaller engine is allowed, then I could have power as needed without a wind generator, which is a small generator or alternator out in the airstream with a little propeller on it (If I faired the generator itself, I could make one with a removable propeller so I could get rid of the drag when I didn't need the juice, but I don't see how you could put it on or take it off without landing). The idea of a high-tech battery sounds interesting, but I wouldn't be needing it just for the avionics but also for the engine. I plan to have a regular VW engine, probably Great Plains, and they normally have one magneto, plus a secondary ignition that's powered by the alternator. So either I'd have to fly on one magneto or have a battery system that's able to put out enough juice to run a VW secondary ignition system for a whole day's flying. Maybe a lithium battery could do that, but I'm not even sure how much juice a VW ignition system uses (or where to find that out). Finally, concerning the charging finickiness of Lithium batteries that Tony mentioned, there's an easy solution to keep charging systems from spiking the voltage too high -- a zener diode. Older British motorcycles like my '72 Norton Commando used this system since before I was born. A zener diode connected to ground is an insulator until the voltage rises to a certain level Then it dumps all voltage above that level to ground. So old British bikes had primitive alternators with voltage that varied widely with engine speed, but they also had a zener diode that dumped any voltage higher than 13.75 V (or something like that) to ground. There are two problems with using a zener diode this way as the only voltage regulation. It's wasteful of power compared to a more sophisticated system that actually regulates the alternator's output. Plus, if it has to dissipate many watts it gets hot, so you need a big zener diode connected to a good heat sink. The Lucas zener diode found on an old British motorcycle is as big as a 3/4" nut, is made of copper, and is bolted to a large aluminum plate out in the airstream. But those systems had to be overbuilt because they're the only voltage regulation the system used. If you had a modern automotive system with occasional pulses high enough to harm a lithium battery, you could use a smaller zener diode with its zener breakdown voltage a tiny bit higher than the one the regular system is supposed to maintain. It would then stop any pulses higher than the breakdown voltage, but the zener wouldn't have to work too hard or dissipate much heat. I assume a system designed for lithium batteries already has something at least this good, but if you plan to drop a lithium battery into a system designed for lead-acid batteries, something like this would help. Mike Taglieri
KR> LiFePO4 Batteries
Hi Tony Do you have internet links to the incidents to which you refer? I would like to read about what caused the incidents as I am currently considering buying one of these batteries and have a few colleagues who have already purchased them. Cheers Gavin Magill Auckland NZ On 16 July 2014 11:02, Tony King via KRnet wrote: > Be very careful with any kind of lithium batteries, including LiFePO4, in > aircraft. I had a Ballistic EVO2 LiFePO4 battery in my aircraft for about > 80 hours with no issues, but I have now removed it after the second of two > significant incidents (one fatal) in Australia caused by LiFePO4 batteries. > I just didn't want to be worrying about it while in the air - especially > since the battery is directly under the seat in my aircraft. > > It's true LiFePO4 is a lot safer than LiPo batteries, but their technical > requirements, discharge characteristics and failure modes are quite > different to lead acid batteries and not well understood by most aircraft > owners. They do not like being heavily discharged and over-voltage during > charging is a definite no no. Typical solid state regulators use pulse > width modulation to achieve a well regulated average voltage, but the > voltage of the pulses is whatever the alternator puts out - which can be as > high as 22 volts, well above the 14.6V limit of LiFePO4 batteries. > > These batteries are being marketed as direct replacements for lead acid and > it's true that for their weight they make great starter batteries. But the > marketing doesn't address the differences with lead acid in any way and the > potential for a fire or the discharge of toxic gases (e.g. hydrogen > flouride) exceeds my comfort level in an aircraft, although I'd use one in > a car or motorbike or the like without hesitation. > > Another aspect that doesn't seem to be well understood is that while a lead > acid battery shows a gradual drop in voltage as it's discharged, lithium > batteries will hold close to the nominal voltage until quite deep in the > discharge cycle and then the voltage will drop very steeply to below useful > levels. This has implications in the event of alternator failure if you're > counting on the battery to run the panel or the ignition. By the time a > drop in voltage is noticed, there's very little time left. > > You might notice too that the marketing for lithium batteries tends to > focus on the cold cranking amps of lithium compared with lead acid and on > that basis lithium batteries look great. But the actual amount of energy > stored in the battery is a lot lower (typically around a third) than a lead > acid battery of equivalent cca performance. This means the lithium battery > won't be able to run a given load (say a glass panel or a radio stack or an > electronic ignition) for as long as a lead acid battery with equivalent > starting performance. > > On the surface these batteries are a great development, but the marketing > that says they're a drop in replacement for lead acid batteries is > misleading. There are several factors that need to be well understood if > you're planning to put one in an aircraft. > > Cheers, > > Tony >
KR> Gathering
hello All, I am now registered for the gathering and just wanted to see if anyone wanted to share a room at the Chino hotel. I will be checking in on the 3rd and departing on the 7th. Sadly, I will be coming via Southwest but that's they way the cookie crumbles. So let me know if anyone's interested. Thanks. Ray_pilot New Orleans
KR> Mailings
Lately my receiving of KRNet has been very spotty. I get every other one then it will skip 10 issues or so and start again. Anybody else having these problems? Also, last issue of Corvaircraft was received on 4/5/2013, Vol. 342 Issue 71. Attempts to contact Corvaircraft site only gets me ?Mail Delivery Failure? notices. Does anyone have any info about this? Thanks, Ken Henderson
KR> "Engine-driven alternator?"
Be very careful with any kind of lithium batteries, including LiFePO4, in aircraft. I had a Ballistic EVO2 LiFePO4 battery in my aircraft for about 80 hours with no issues, but I have now removed it after the second of two significant incidents (one fatal) in Australia caused by LiFePO4 batteries. I just didn't want to be worrying about it while in the air - especially since the battery is directly under the seat in my aircraft. It's true LiFePO4 is a lot safer than LiPo batteries, but their technical requirements, discharge characteristics and failure modes are quite different to lead acid batteries and not well understood by most aircraft owners. They do not like being heavily discharged and over-voltage during charging is a definite no no. Typical solid state regulators use pulse width modulation to achieve a well regulated average voltage, but the voltage of the pulses is whatever the alternator puts out - which can be as high as 22 volts, well above the 14.6V limit of LiFePO4 batteries. These batteries are being marketed as direct replacements for lead acid and it's true that for their weight they make great starter batteries. But the marketing doesn't address the differences with lead acid in any way and the potential for a fire or the discharge of toxic gases (e.g. hydrogen flouride) exceeds my comfort level in an aircraft, although I'd use one in a car or motorbike or the like without hesitation. Another aspect that doesn't seem to be well understood is that while a lead acid battery shows a gradual drop in voltage as it's discharged, lithium batteries will hold close to the nominal voltage until quite deep in the discharge cycle and then the voltage will drop very steeply to below useful levels. This has implications in the event of alternator failure if you're counting on the battery to run the panel or the ignition. By the time a drop in voltage is noticed, there's very little time left. You might notice too that the marketing for lithium batteries tends to focus on the cold cranking amps of lithium compared with lead acid and on that basis lithium batteries look great. But the actual amount of energy stored in the battery is a lot lower (typically around a third) than a lead acid battery of equivalent cca performance. This means the lithium battery won't be able to run a given load (say a glass panel or a radio stack or an electronic ignition) for as long as a lead acid battery with equivalent starting performance. On the surface these batteries are a great development, but the marketing that says they're a drop in replacement for lead acid batteries is misleading. There are several factors that need to be well understood if you're planning to put one in an aircraft. Cheers, Tony On 16 July 2014 02:08, brian.kraut--- via KRnet wrote: > Lithium Iron Phosphate batteries are the way to go with aircraft. They > have near the capacity to weight and size ratio as Lithim Ion and and > Lithium Polymer, but they are many times safer. There is a ton of > information on them on the web a Google search away. The biggest > drawback to most of the Lithium varieties after getting over the safety > factor is that the cells really need to be balance charged correctly. > EarthX now has batteries that have all of the complicated charging > electronics built in the battery. I got one for my avionics backup for > the Mustang 2. I have enough capacity in just 1.3 pounds to fly IFR > until my fuel tank runs dry if I loose my primary battery and > alternator. EFIS automatically switches with its built in two power > source configuration and I have off/main/backup switches for my nav and > com radios and my EIS engine monitor. Probably will add the backup > position switch to my transponder at some point also. > > I highly recommend EarthX and many years from now when my PC680 main > starting battery goes I will replace it with a 2-3 pound EarthX. > > http://earthxmotorsports.com/ > > > > Original Message > Subject: Re: KR> "Engine-driven alternator?" > From: Jeff Scott via KRnet > Date: Tue, July 15, 2014 7:52 am > To: krnet > > If your plan is to operate a Mode-S with ES transponder, or a UAT Out > along with Mode C transponder to comply with the 2020 mandate, along > with a low wattage Comm radio, I would suggest that your lightest option > would be a light weight solar charger and either a Lithium Ion or > Lithium Polymer battery pack. The solar charged LiPo combination gives > you a lot of useful time with the avionics necessary to fly in your area > without a huge weight penalty. > > Caveat: The Lithium Ion and especially the Lithium Polymer batteries can > be a fire danger if discharged too rapidly (heavy loads like a starter) > or in a crash scenario if they are punctured. However, when I was > working in the UAV/Drone world we used Lithium Polymer batteries > exclusively and had some very high G impact crashes. The only damage we > ever saw with the Li-Po
