Scratch Two More

A place to relax and discuss flying topics.

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DaveF
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Re: Scratch Two More

Post by DaveF »

Bill,

I was sorely tempted by the PAR200, but didn't need another com. I have no experience with it, but I've owned several PS Engineering audio panels and intercoms and they're all excellent. I wouldn't buy anything else.

Dave
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blueldr
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Re: Scratch Two More

Post by blueldr »

intellerstellardust,

I have no personal experience with the electronics shop at Calaveras County Airport, but my friends at Westover Field in Jackson, CA, seem to speak well of them.

The Av Gas price is generally quite favorable there also.
BL
bagarre
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Re: Scratch Two More

Post by bagarre »

I didn't find a VFR radio install to be particularly difficult.
Even with a 4 place intercom, there are only a handful of wires. I borrowed a crimper tool and finished mine in a weekend.
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interstellardust
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Re: Scratch Two More

Post by interstellardust »

DaveF wrote:Bill,

I was sorely tempted by the PAR200, but didn't need another com. I have no experience with it, but I've owned several PS Engineering audio panels and intercoms and they're all excellent. I wouldn't buy anything else.

Dave
Thanks Dave. Watching the video about the PAR200 makes it look attractive. The bit that made me a bit nervous is that the volume knobs seemed to wiggle quite a bit. perhaps that's just because they also have push functions built in. http://youtu.be/irgVCLd0rNA

I have always thought I would upgrade to a Garmin COM as when I hear a really clear radio in the air, it always turns out to be a Garmin when I catch up to it on the ground.

Basically I'm trying to decide between the the PS PAR200 and a Garmin with or without an AP. I rarely have more than 2 people in the plane but I do have 2 radios. Right now there is a toggle switch to select which radio to transmit from. I can hear both if I turn them both on. The Garmins have 2 place intercoms in them, but I don't think that helps if I use the old KX170B.

Speaking of the KX170B, has anyone used G.G.Glassmeyer's radio repair services? He's a "retired" avionics guy who only works on KX170B radios and associated VOR heads.
Bill Garnett
1955 Cessna 170B N2974D
bill@interstellardust.com
voorheesh
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Re: Scratch Two More

Post by voorheesh »

Regarding the installation of avionics in certificated aircraft: This must be accomplished in accordance with Part 43 and without going into excessive detail, that requires the installer to verify the installation uses materials and methods that ensure the aircraft will remain in a condition equal to its original certification basis. I am paraphrasing, but look at 43.13 (a) & (b). An A&P mechanic is responsible for this if he/she installs a radio. Most avionics shops are Part 145 Repair Stations and they are required to adhere to Part 43 also. Installation by other than a certificated person/organization is contrary to FAR. If specialized tests are necessary such as transponders, a rated repair station is necessary. It is true that a TSO is not specifically required for a communications radio, but a TSO represents a standard that an installer can rely upon to ensure the product meets the "airworthiness" requirements of the certificated aircraft being worked on/altered per Part 43. (there may also be other applicable standards that can meet the same requirements) By using TSO'd products, you are assured that they meet a wide variety of safety standards that are appropriate to aviation use. Put yourself in the position of a Repair Station owner or manager. Why would you take on the liability and possible regulatory issues involved with installing a product that has not been accepted for this use? Please do not blame professional technicians who are caught in the middle of this issue.

Why not contact Garmin or any other manufacturer of equipment intended for experimental use and request that you be provided with data that will demonstrate the aviation standards of their product? Ask them why it is appropriate for an experimental aircraft and not a certificated one. Why did they not submit this product to the FAA for some certification standard such as a TSO per Part 21? Ask Garmin if they would support installing this equipment in a certificated aircraft.

The standards for experimental aircraft are to the benefit of the owners of such aircraft and are significantly less demanding than the standards that apply to certificated aircraft such as our Cessna 170s. I believe it is mixing apples and oranges to compare the two. I think the answer may lie in our ability to fly experimental products if that technology is more appealing. (Note: My opinion only and per Bruce, may be worth what you paid for it :D )
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W.J.Langholz
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Re: Scratch Two More

Post by W.J.Langholz »

What I have always been curious about is.... let's say item "A" is a TSO item. How many of item "A" are actually tested and inspected ? 1 out of 3, 1 of 6, 1 of 20 ? Does anybody know?


W.
ImageMay there always be and Angel flying with you.
Loyalty above all else except honor.
1942 Stearman 450
1946 Super Champ 7AC
voorheesh
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Re: Scratch Two More

Post by voorheesh »

[quote="W.J.Langholz"]What I have always been curious about is.... let's say item "A" is a TSO item. How many of item "A" are actually tested and inspected ? 1 out of 3, 1 of 6, 1 of 20 ? Does anybody know?

The answer to your question depends on the holder of the TSO and their quality control program. The FAA awards Technical Standard Orders to applicants who meet the requirements of 14 CFR 21 Subpart O Technical Standard Order Approvals. This regulation contains all the requirements which include a quality management and assurance program. Most TSO holders are advanced engineering/manufacturing organizations who are operating at least at an ISO 9000 level and develop comprehensive programs that ensure their products meet design criteria and performance expectations on a continual and reliable basis. These products are also subject to in service surveillance and reporting. They sometimes generate service bulletins, letters, airworthiness directives and other safety assurance programs. I would urge any interested pilots to contact the manufacturer/TSO holder (such as Garmin) for further information on this subject. Some of this is proprietary but I believe a TSO holder's FAA approval documents including their QC programs may be in the public domain. Apologies for being the resident rule expert (maybe not/waiting for incoming on the Part 43 observations).
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W.J.Langholz
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Re: Scratch Two More

Post by W.J.Langholz »

No you are doing fine on the rules, that's how we all learn. Everyone here has something to share, this subject happens to be your area.

The reason I ask is my son (whom I like to brag about) with 2 engineering degrees, is now doing PRA (Product Risk Analysis ) with a large firm finds that most QA company programs fall way short of what is actually being done and is more paper than practice for the Government. He currently does not do anything with aviation so I can not comment if the aviation community is the same.
It does get a bit scary when you see all the product recalls from companies with supposedly "Excellent" QA programs. If you test less you have a high level of compliance, if you test more you may not pass the government guide lines..... and so goes big business and a push for profit margins.

I will agree with you that if it is a product that is of significant that would effect the flight or control of your aircraft that a call to the manufactory is in order. Get ready for all the buss words that make them sound really good but keep after it until you get some facts.

Thank you again Mr V for your input I do like your comments and will continue to ask more questions in hopes of always learning. Thanks for sharing.



W.
ImageMay there always be and Angel flying with you.
Loyalty above all else except honor.
1942 Stearman 450
1946 Super Champ 7AC
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jrenwick
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Re: Scratch Two More

Post by jrenwick »

Many manufacturing processes only examine a small percentage of the articles coming off the line. For a certain production volume or manufacturing process, you can say that statistically you only need to look at X percent of the product to assure that you have less than 0.001% defects (or what ever your quality criterion is).

The problem with quality control is that you can only find the problems you can design tests for. So many things happen in the field that engineers didn't anticipate.
John Renwick
Minneapolis, MN
Former owner, '55 C-170B, N4401B
'42 J-3 Cub, N62088
'50 Swift GC-1B, N2431B, Oshkosh 2009 Outstanding Swift Award, 2016 Best Continuously Maintained Swift
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W.J.Langholz
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Re: Scratch Two More

Post by W.J.Langholz »

yes John and If you don't "test" you can honestly say you don't have a problem. And you can design a test that will make you look good as well. If a Business hires a independent PRA firm then the test are legit. If only someone would have done a PRA at Fukushima Japan and saw that the back up generators were in the basement on a Nuclear plant located close to the shore where flooding is prevalent, and moved them up to the 3rd floor the outcome would have been way different. At the time they were in compliance with all the regs. I would be vary wary of in house statistical data on any product.


W.
ImageMay there always be and Angel flying with you.
Loyalty above all else except honor.
1942 Stearman 450
1946 Super Champ 7AC
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GAHorn
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Re: Scratch Two More

Post by GAHorn »

voorheesh wrote:Regarding the installation of avionics in certificated aircraft: This must be accomplished in accordance with Part 43 and without going into excessive detail, that requires the installer to verify the installation uses materials and methods that ensure the aircraft will remain in a condition equal to its original certification basis. I am paraphrasing, but look at 43.13 (a) & (b). An A&P mechanic is responsible for this if he/she installs a radio. Most avionics shops are Part 145 Repair Stations and they are required to adhere to Part 43 also. Installation by other than a certificated person/organization is contrary to FAR. If specialized tests are necessary such as transponders, a rated repair station is necessary. It is true that a TSO is not specifically required for a communications radio, but a TSO represents a standard that an installer can rely upon to ensure the product meets the "airworthiness" requirements of the certificated aircraft being worked on/altered per Part 43. (there may also be other applicable standards that can meet the same requirements) By using TSO'd products, you are assured that they meet a wide variety of safety standards that are appropriate to aviation use. Put yourself in the position of a Repair Station owner or manager. Why would you take on the liability and possible regulatory issues involved with installing a product that has not been accepted for this use? Please do not blame professional technicians who are caught in the middle of this issue.

Why not contact Garmin or any other manufacturer of equipment intended for experimental use and request that you be provided with data that will demonstrate the aviation standards of their product? Ask them why it is appropriate for an experimental aircraft and not a certificated one. Why did they not submit this product to the FAA for some certification standard such as a TSO per Part 21? Ask Garmin if they would support installing this equipment in a certificated aircraft.

The standards for experimental aircraft are to the benefit of the owners of such aircraft and are significantly less demanding than the standards that apply to certificated aircraft such as our Cessna 170s. I believe it is mixing apples and oranges to compare the two. I think the answer may lie in our ability to fly experimental products if that technology is more appealing. (Note: My opinion only and per Bruce, may be worth what you paid for it :D )
The installation should follow the avionics approved installation instructions AND the FARs. Any person may make the installation but should do so under the direct supervision of an A&P who will make the log entry. The log entry should indicate that the installation was made in accordance with the mfr's installation instructions AND the FAR's. (The approved installation instructions may contain procedures not specified in 43.)
The reason a mfr'r may not seek TSO for his product is to avoid the expensive costs for that certification which may not provide any measureable benefit.
The tests of txdrs do not necessarily require a repair station,....there are other authorized persons as well.
TSO is often beneficial when making multiple installations which require extensive interfacing. TSO'd equipment has been tested/certified to interface with other TSO'd equipment...OR...any deficiencies will be noted. An excellent example of how TSO may provide no meaningful benefit (and be a waste of money) are those TSO'd transmitters which interfere with certain GPS equipment on some frequencies. All the TSO provides in that case is a warning in the operations manual and a suggested work-around. The non-TSO'd radios do the same, so no benefit that I can see in simple installations like C-170s.
But a TSO will likely insure that your transmitter won't make your TSO'd autopilot disconnect on short ILS simply because you keyed the mic button. 8O
Another claim for TSO'd equip't is the installation of an FM/CD player in your avionics rack. An automotive unit will likely have automotive wiring in it...not approved aviation-quality components....hence the reluctance of most repair stations to make such installations of non-TSO'd equip't.

But it's fairly clear that such things as 760 channel aviation-band transmitters sold primarily to aircraft owners for aircraft installations are often a good buying decision in simple airplanes, and it's ridiculously ignorant of an avionics facility to refuse to make that sale and installation. (I suspect that in many cases it's because they're protecting their distributorship position with other brands. The VAL and Icom radios are often repaired by their factories and avionics shops don't want to deal with that competition. They'd rather deal with mfr's who make them "authorized" dealerships and will invest in the testing and repair equipment and training that entails.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
flyboy122
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Re: Scratch Two More

Post by flyboy122 »

TSO isn't technically required to install a piece of equipment in a certified aircraft, but without it the onus is on the installer to prove to the FAA that the equipment is safe and meets the applicable standards. For something like a cigarette lighter, or even a FM car radio, usually you can get by on the 337 by changing all the wiring to aircraft wiring and showing that it is purely accessory equipment. But with a VHF radio or audio panel, that's whole different level of integration that affects the aircraft's ability to communicate. It may not be necessary by the letter of the law in certain airspace, but the FAA assumes (rightly) that you'll use it in class B or similar airspace where it would be required. Thus they are concerned about the equipment itself.

Nowadays pretty much any electronic equipment such as radios, transponders, etc... require DO-160 environmental testing. If it has software, they'll want DO-178 testing. This is part of what the OEM does to get TSO, and when the feds see that TSO it gives them a warm fuzzy that the testing has been done. This testing is not insignificant. I've seen DO-160 tests run 50-100k, and there is no guarantee it will pass, in which case you fix it and run the test over again. I've never done DO-178 testing, but it's mention tends to strike fear into the faces of avionics engineers. Apparently it's orders or magnitude more difficult than DO-160. Google "National Testing Services" (NTS) to see who does this kind of work. It's kind of interesting.

Testing of TSO'd avionics is different at every OEM, and may be different amongst the products they make. Depending on the OEM, you can often get copies of the "Bench Test" reports. Last time I checked Bendix King will provide them, Garmin won't.

DEM
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GAHorn
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Re: Scratch Two More

Post by GAHorn »

flyboy122 wrote:TSO isn't technically required to install a piece of equipment in a certified aircraft, but without it the onus is on the installer to prove to the FAA that the equipment is safe and meets the applicable standards. ...DEM
That supporting documentation is always included in the package from such OEMs as VAL, Icom, etc. Example, even the VAL sales brochures state:
"•Meets or exceeds TSO standards.
•Acceptable for installation in type-certificated aircraft.

The Icom radios state "Measurements made in accordance with RTCA DO-186B for USA version" which is all that req'd but they also meet Mil-Specs and state those other qualification.

In other words.... if all you want is simple avionics, those major mfr's products are not to be shunned merely because no TSO is offered, and you shouldn't let scare/threat stories do anything other than fill you with disdain for that sort of behavior. IMO
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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