---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Tue 07/01/03: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:11 AM - Re: ELT (Fred Fillinger) 2. 05:15 AM - Re: ELT (James Nelson) 3. 06:28 AM - Re: Primer for Zn-coated steel (Cy Galley) 4. 07:18 AM - Re: Primer for Zn-coated steel (R.C.Harrison) 5. 07:29 AM - Re: Primer for Zn-coated steel (TELEDYNMCS@aol.com) 6. 08:05 AM - Re: Primer for Zn-coated steel (R.C.Harrison) 7. 11:11 AM - Re: Primer for Zn-coated steel (Rob Housman) 8. 01:08 PM - Re: Primer for Zn-coated steel (Jeremy Davey) 9. 01:09 PM - Antennas (Fergus Kyle) 10. 06:16 PM - Re: Antennas (Fred Fillinger) ________________________________ Message 1 _____________________________________ Time: 05:11:24 AM PST US From: Fred Fillinger Subject: Re: Europa-List: ELT --> Europa-List message posted by: Fred Fillinger > What happens if one were to mount the antenna horizontally? > > Is there a need for a ground plane in a composite aircraft? > > I would appreciate installation tips from builders who have > figured this out already. The antenna should be mounted vertically to match the orientation of a receiver's signal. A very good -0- cost ELT antenna which does not require a ground plane can be made from the last 21" of the RG-58 antenna coax. Remove 21" of insulation. Push on the braid along its length to expand it and pull the center conductor out from the braid at the 21" point. Bond it to the side of the fuselage oriented vertically, except form a "V" by orienting each leg 20-deg from vertical. Check and or cut the length of the braid leg to remain at 21". The horizontal run of the coax must be horizontal for at least 21" before taking any vertical turn: / / 21" / ------------- >= 21" \ \ 21" \ Fred F. ________________________________ Message 2 _____________________________________ Time: 05:15:05 AM PST US Subject: Re: Europa-List: ELT From: James Nelson --> Europa-List message posted by: James Nelson Craig, I also have the same ELT. However I mounted it just behind the pilot. Just under the door rebate about 2" down. Why?, well that unit can be removed from the a/c when you are down and take it with you. If you have it beneath the rear deck, it becomes impossible to take with you. Plus, at your yearly annual inspection, you just remove the two straps and take it out and replace the "D" batterys. I went to an electronics store and got a 90 degree antenna fitting so the unit could be mounted fairly close toward the front. I mounted the antenna just behind the rear bulkhead with the antenna pointed vertical. You need a vertically polarized signal for best reception. (don't ask about an inverted landing). I then mounted the antenna on a 1-1/2" square aluminum tube. The tube was glassed to the bottom of the fuselage with 4 layers of bid. I had a 1/4" hold drilled on the side to bolt the ground plane copper tapes to. The ground plane radials are necessary to produce a strong signal. However, without a ground plane it still works. (note the portable hand held radios by Icom ect. But your DAR may want the radials so I mounted them (6) and put one layer of glass over them to protect them. I folded the tapes over on them selves at the end that has to be bolted to the aluminum tube so it would be stronger. I soldered the fold over so the washer would not bread the tapes. Obviously do all the mod's to the aluminum piece before mounting for the last time. The antenna tip was supported at the top by reduxing a 1" dia. (thin wall) irrigation tube to the back of the "D" removable panel. This way the loading coil is contained with in the short plastic tube and can't flop around. The mounting pads for the ELT unit were 3/8" thick plywood reduxed to the side of the fuselage. These were about 1-1/4 wide and about 3" long. Can not remember the exact size but you will see how to match to the provided mounting bracket from the manufacturer.(this was done a long time ago, memory short, old timers disease) Jim Nelson N15JN (still holding at 42 hours, rain go away. For the last month, its rained every weekend) On Mon, 30 Jun 2003 22:56:33 -0700 "craig ellison" writes: > --> Europa-List message posted by: "craig ellison" > > > All, > > I just received my Ameri-King ELT from AS and was going over the > install instructions before mounting it under the baggage > compartment. I was planning to mount the antenna on the back side > of the baggage bay bulkhead in the horizontal position, but the > instructions state that the antenna should be 20 degrees of vertical > when the aircraft is in a normal flight attitude and if it is > mounted to a non-metallic air frame, a supplementary ground plane > must be installed. > > What happens if one were to mount the antenna horizontally? > > Is there a need for a ground plane in a composite aircraft? > > I would appreciate installation tips from builders who have figured > this out already. > > Thanks in advance > > Craig Ellison > A205 > > > > > > > > > > ________________________________ Message 3 _____________________________________ Time: 06:28:02 AM PST US From: "Cy Galley" Subject: Re: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: "Cy Galley" If the tubes are steel, powder coating is o.k. Aluminum may not as the fusing temperature may alter the strength and temper of the aluminum. FAA will not approve aluminum to be powder coated for certified aircraft, so you might do some checking before using this process. Cy Galley Editor, EAA Safety Programs cgalley@qcbc.org or experimenter@eaa.org ----- Original Message ----- From: Subject: Re: Europa-List: Primer for Zn-coated steel > --> Europa-List message posted by: DuaneFamly@aol.com > > > I concur with Rob on the tubes being aluminum. Your magnet test will be > conclusive. I chose to take most of the tubing from the kit and sent it out to be > powder coated. They will clean and coat it and you should never have a problem. > You can also pick a nice color. The cost to me was about $80 US and three > days time. Make sure you mask off the bottom of the control sticks where they go > into the CS01 with CS16b spacer. It's a snug fit to begin with. > > Mike Duane A207 > Redding, California > XS Trigear > > ________________________________ Message 4 _____________________________________ Time: 07:18:17 AM PST US From: "R.C.Harrison" Subject: RE: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: "R.C.Harrison" Well said CY. Those choosing to ignore this advice do so at their peril. I'm sure that the Europa Club Safety Representative and /or the PFA delegated metalurgist will pass likewise statements also to this effect? regards Bob Harrison G-PTAG -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com]On Behalf Of Cy Galley Subject: Re: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: "Cy Galley" If the tubes are steel, powder coating is o.k. Aluminum may not as the fusing temperature may alter the strength and temper of the aluminum. FAA will not approve aluminum to be powder coated for certified aircraft, so you might do some checking before using this process. Cy Galley Editor, EAA Safety Programs cgalley@qcbc.org or experimenter@eaa.org ----- Original Message ----- From: Subject: Re: Europa-List: Primer for Zn-coated steel > --> Europa-List message posted by: DuaneFamly@aol.com > > > I concur with Rob on the tubes being aluminum. Your magnet test will be > conclusive. I chose to take most of the tubing from the kit and sent it out to be > powder coated. They will clean and coat it and you should never have a problem. > You can also pick a nice color. The cost to me was about $80 US and three > days time. Make sure you mask off the bottom of the control sticks where they go > into the CS01 with CS16b spacer. It's a snug fit to begin with. > > Mike Duane A207 > Redding, California > XS Trigear > > ________________________________ Message 5 _____________________________________ Time: 07:29:48 AM PST US From: TELEDYNMCS@aol.com Subject: Re: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: TELEDYNMCS@aol.com In a message dated 7/1/2003 9:29:03 AM Eastern Daylight Time, cgalley@qcbc.org writes: > If the tubes are steel, powder coating is o.k. Aluminum may not as the > fusing temperature may alter the strength and temper of the aluminum. FAA > will not approve aluminum to be powder coated for certified aircraft, so you > might do some checking before using this process. Powder coating is also known for hiding cracks, especially in welded areas. Before I found this out I had my nose gear mount and rudder pedals powdercoated. I was happy with the finish until I started handling and installing the parts. The tubing was zinc coated to start with (shiney, gold finish) and now the powder coat is chipping off. I will likely scuff sand and repaint with Corlar primer, then a top coat. Regards, John Lawton Dunlap, TN A-245 ________________________________ Message 6 _____________________________________ Time: 08:05:54 AM PST US From: "R.C.Harrison" Subject: RE: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: "R.C.Harrison" Hi! John. I believe that sanding is "bad news" with likelihood of inducing fatigue cracks better degrease and aerosol spray IMHO. Pencil marks and the like have been known to be an issue also? Suggest those competants in this field will advice the forum ? Of course scuff sanding is often called for on embedded components but I guess they don't get the stresses of flexing in that position? Regards Bob Harrison G-PTAG -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com]On Behalf Of TELEDYNMCS@aol.com Subject: Re: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: TELEDYNMCS@aol.com In a message dated 7/1/2003 9:29:03 AM Eastern Daylight Time, cgalley@qcbc.org writes: > If the tubes are steel, powder coating is o.k. Aluminum may not as the > fusing temperature may alter the strength and temper of the aluminum. FAA > will not approve aluminum to be powder coated for certified aircraft, so you > might do some checking before using this process. Powder coating is also known for hiding cracks, especially in welded areas. Before I found this out I had my nose gear mount and rudder pedals powdercoated. I was happy with the finish until I started handling and installing the parts. The tubing was zinc coated to start with (shiney, gold finish) and now the powder coat is chipping off. I will likely scuff sand and repaint with Corlar primer, then a top coat. Regards, John Lawton Dunlap, TN A-245 ________________________________ Message 7 _____________________________________ Time: 11:11:51 AM PST US From: "Rob Housman" Subject: RE: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: "Rob Housman" Bob, I suspect your comment in re: sanding was directed at my earlier post, not John's post on the same subject (below). First, by "sanding" I was suggesting a fine grit which in this context I meant 600 grit (US terminology) which will definitely not harm the aluminum. Scuff sanding on the other hand is far more aggressive than I had in mind, and though I doubt even that would cause trouble over time I would not do it on these tubes. Early in my engineering career my business card said I was an extrusion engineer for an aluminum company but in reality I was the technical support for an aluminum tube manufacturing operation (said tubes being cold drawn from extruded "bloom" - thick walled extruded tube) so I have a good technical understanding of things made out of aluminum, especially tube. My suggesting mechanical removal of the oxide film was as an alternative to chemical treatment, not as alternative to degreasing. No amount of degreasing will help organic coatings stick to aluminum. In order for any coating to adhere to any aluminum surface, that oxide film must first be removed. Of course "removed" is a misnomer because it will instantly reform once the bare aluminum is exposed to oxygen, but chemical or mechanical treatment will make it less of a problem. Best regards, Rob Housman Europa XS Tri-Gear A070 Airfarame complete Irvine, CA -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com]On Behalf Of R.C.Harrison Subject: RE: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: "R.C.Harrison" Hi! John. I believe that sanding is "bad news" with likelihood of inducing fatigue cracks better degrease and aerosol spray IMHO. Pencil marks and the like have been known to be an issue also? Suggest those competants in this field will advice the forum ? Of course scuff sanding is often called for on embedded components but I guess they don't get the stresses of flexing in that position? Regards Bob Harrison G-PTAG -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com]On Behalf Of TELEDYNMCS@aol.com Subject: Re: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: TELEDYNMCS@aol.com In a message dated 7/1/2003 9:29:03 AM Eastern Daylight Time, cgalley@qcbc.org writes: > If the tubes are steel, powder coating is o.k. Aluminum may not as the > fusing temperature may alter the strength and temper of the aluminum. FAA > will not approve aluminum to be powder coated for certified aircraft, so you > might do some checking before using this process. Powder coating is also known for hiding cracks, especially in welded areas. Before I found this out I had my nose gear mount and rudder pedals powdercoated. I was happy with the finish until I started handling and installing the parts. The tubing was zinc coated to start with (shiney, gold finish) and now the powder coat is chipping off. I will likely scuff sand and repaint with Corlar primer, then a top coat. Regards, John Lawton Dunlap, TN A-245 ________________________________ Message 8 _____________________________________ Time: 01:08:38 PM PST US From: "Jeremy Davey" Subject: RE: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: "Jeremy Davey" Thanks for the input, Gents. It appears there has been a change of materials. Mine are steel, zinc coated with a chromic passivation (no, I'm not an expert on coatings, I asked the factory :-) ) that gives them a golden appearance similar to the cadmium on many AN fittings. To be clear, these are the tubes under the seats and the tubes inside those. I'd have to dig it out to check, but I think the pitch torque tube is the same, too. I've got some PolyFiber Metal Prime to hand, so unless someone has any brilliant ideas, I guess I'll try that... Powder coating is out as the rear bearings are already installed and, having removed and rebonded one last night (acquiring numerous burns on my fingers in the process - must buy some leather gloves), I ain't doin' that again in a hurry! Cheers, Jeremy Jeremy Davey Europa XS Monowheel 537M G-EZZA -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of DuaneFamly@aol.com Subject: Re: Europa-List: Primer for Zn-coated steel --> Europa-List message posted by: DuaneFamly@aol.com I concur with Rob on the tubes being aluminum. Your magnet test will be conclusive. I chose to take most of the tubing from the kit and sent it out to be powder coated. They will clean and coat it and you should never have a problem. You can also pick a nice color. The cost to me was about $80 US and three days time. Make sure you mask off the bottom of the control sticks where they go into the CS01 with CS16b spacer. It's a snug fit to begin with. Mike Duane A207 Redding, California XS Trigear ________________________________ Message 9 _____________________________________ Time: 01:09:48 PM PST US From: "Fergus Kyle" Subject: Europa-List: Antennas --> Europa-List message posted by: "Fergus Kyle" Hi I see a number of messages regarding installation of antennas (aerials) which indicate only a slight understanding of how they work. Most VHF sets use a 1/4wavelength vertical antenna. If remote, this antenna requires a groundplane which allows it full output if sized to agree with the 50ohms in the coax cable. This size is 5% larger than the antenna pole and can be as simple as two or three wires at equidistant angles to each other. The handhelds have nothing like this antenna, and are particular to the handheld itself - they are a different animal. It's true that without a groundplane the signal will spill out, but most of it is swamped by imporper impedance - and ELTs are insufficient enough without stifling the signal further. If the ELT has provision for an antenna on its body, keep it there and mount it where the antenna is relatively clear of large metal bits. Connect a remote antenna incorrectly and kiss goodbye to 90% of the vital message it may need to send one day. Or contact a nearby ham of 30 years experience for a useful word. Cheers, Ferg VE3LVO ________________________________ Message 10 ____________________________________ Time: 06:16:37 PM PST US From: Fred Fillinger Subject: Re: Europa-List: Antennas --> Europa-List message posted by: Fred Fillinger Fergus Kyle wrote: > and ELTs are insufficient enough without stifling the signal > further. You may be amused by my running a 160 milliwatt ELT thru Jim Weir's (RST Engineering) RF calculator spreadsheet. It will have a theoretical reception area of 980 thousand square miles! It doesn't help if you've engineered a perfect antenna install, but with the antenna oriented vertically, because there will be a big void overhead in the center of the "donut." That's why previous posts mentioned tilting it 20-degrees to fill in the void. Our gov't also says typical location accuracy is 12 miles even at required 100 milliwatts (lesser the better for this purpose). A variety of reasons make it difficult to find you within the center of the radiation pattern, if it's anything close to circular at all. Thus mythology that high signal strength is always good and that it's easy to home in on the signal. Fastest and most assured rescue, if a cell phone won't work, is direct VHF comm with passing overhead aircraft, ideally with GPS coordinates. Also the 121.5 mHz ELT's will be phased out in a few years. Fred F.