Oh, I see (said the blind man as he picked up his hammer and saw).
They don’t trust Google Earth or topo maps for ground elevation? From: AF <af-boun...@af.afmug.com> On Behalf Of Brian Webster Sent: Wednesday, April 15, 2020 4:21 PM To: 'AnimalFarm Microwave Users Group' <af@af.afmug.com> Subject: Re: [AFMUG] TOWAIR and ASR for existing tower It’s not the structure height they add the margin to, it’s the stated ground elevation your structure is located on that they are concerned with. Thank you, Brian Webster www.wirelessmapping.com <http://www.wirelessmapping.com> From: AF [mailto:af-boun...@af.afmug.com] On Behalf Of Ken Hohhof Sent: Wednesday, April 15, 2020 5:12 PM To: 'AnimalFarm Microwave Users Group' Subject: Re: [AFMUG] TOWAIR and ASR for existing tower As far a height, a surveyor is not really needed. It’s 5 sections of Rohn with 5 feet buried in the ground, the laser rangefinder says 45 feet, or we can do a tape drop. You don’t need to be a surveyor to use a tape measure. I understand the lat/lon thing, but I have readings from a Garmin handheld that says it is within 10 feet. Centimeter accuracy should not be necessary when we are half a mile away. The annoying thing is there are utility poles along the road between us and the airport that are over 40 feet. From: AF <af-boun...@af.afmug.com <mailto:af-boun...@af.afmug.com> > On Behalf Of Brian Webster Sent: Wednesday, April 15, 2020 3:45 PM To: 'AnimalFarm Microwave Users Group' <af@af.afmug.com <mailto:af@af.afmug.com> > Subject: Re: [AFMUG] TOWAIR and ASR for existing tower There is a document standard published from the FAA as to the reporting standards. I haven’t looked at that in 20 plus years but it does exist. You are right Lewis, for a surveyor who is probably using a survey grade GPS that has sub centime accuracy, their measurement is going to exceed either standard for quality. It’s all in what is printed on the document you submit. Thank you, Brian Webster www.wirelessmapping.com <http://www.wirelessmapping.com> From: AF [mailto:af-boun...@af.afmug.com] On Behalf Of Lewis Bergman Sent: Wednesday, April 15, 2020 3:26 PM To: AnimalFarm Microwave Users Group Subject: Re: [AFMUG] TOWAIR and ASR for existing tower Many surveyors don't have any idea what that 1A should look like so they are lost. The cost to do a 1A and 2C is the same and their accuracy exceeds both of those requirements. If you need an example letter I produced and have had successfully filed and completed the process with I can send you one. On Wed, Apr 15, 2020 at 2:20 PM Brian Webster <i...@wirelessmapping.com <mailto:i...@wirelessmapping.com> > wrote: Tim is correct. TOWAIR will err on the conservative side so that if something is a close call, it will defer that decision to the FAA to do their precise study. A couple of key things to note. If you do have to file, always get a 1A qualified survey letter and send it with your application for study. This will allow the FAA to know that the vertical margin of error for the elevation information you filled in can only be 3 feet. If you file a 2C survey letter they still assume a 20 foot vertical margin of error and they add that to your structure height. If you don’t supply either letter I think they add 50ft to your applied for height. Of other additional note, your state DOT and the local airport authority actually have more authority to require marking and lighting if they deem it necessary. When you file for an FAA determination, the FAA forwards your request to them for review as well. I had a tower application actually come back clear from the FAA but the Washington State DOT (aeronautical division) require that the tower be marked and lit. Most people don’t know that this can happen. If you want to study it quietly to know if you are possibly in violation, check with the folks at www.airspaceusa.com <http://www.airspaceusa.com> . They can run all the same studies the FAA will. Part of any FAA study is not only height clearance but they do study for RFI and possible radar blockages. RFI specifically as it might apply to any radio navigation systems. Technically if you add any transmitter to a tower that did not have those frequencies in the original application, you need to file again even if you don’t change the height so that they can do an RFI study again. Thank you, Brian Webster www.wirelessmapping.com <http://www.wirelessmapping.com> From: AF [mailto:af-boun...@af.afmug.com <mailto:af-boun...@af.afmug.com> ] On Behalf Of Tim Hardy Sent: Wednesday, April 15, 2020 11:59 AM To: AnimalFarm Microwave Users Group Subject: Re: [AFMUG] TOWAIR and ASR for existing tower The FAA Notice Criteria tool mentioned by Lewis is also more accurate than TOWAIR and we have seen instances where it will clear towers that TOWAIR failed. All we had to do was file the FAA Report data along with the TOWAIR data and the application was accepted. On Apr 14, 2020, at 7:45 PM, Lewis Bergman <lewis.berg...@gmail.com <mailto:lewis.berg...@gmail.com> > wrote: The FAA had a tool to determine if you have to file. https://oeaaa.faa.gov/oeaaa/external/gisTools/gisAction.jsp?action=showNoNoticeRequiredToolForm On Tue, Apr 14, 2020, 5:47 PM Ken Hohhof <af...@kwisp.com <mailto:af...@kwisp.com> > wrote: We have a tower next to a commercial building, I think it’s a 45 or 50 ft probably Rohn 45G. It is near a smallish regional airport but pretty much 90 degrees to the runway. We need to swap out the 5 GHz backhaul links on this tower for licensed. The frequency coordinator is telling us that according to TOWAIR we need to file for an ASR, I assume they mean not just with the FCC but with the FAA. By doing so, are we opening Pandora’s box, where they tell us not only is our request denied, we have to take down the tower that has been there for 20 years? Is this one of those things where we will really regret asking the question and should have just kept quiet and suffered with the 5 GHz interference? -- AF mailing list AF@af.afmug.com <mailto:AF@af.afmug.com> http://af.afmug.com/mailman/listinfo/af_af.afmug.com -- AF mailing list AF@af.afmug.com <mailto:AF@af.afmug.com> http://af.afmug.com/mailman/listinfo/af_af.afmug.com -- AF mailing list AF@af.afmug.com <mailto:AF@af.afmug.com> http://af.afmug.com/mailman/listinfo/af_af.afmug.com -- Lewis Bergman 325-439-0533 Cell
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