Wake Turbulence Radar/Twr

Maybe local, yes. But the 3120.4 is clear, you have to go, however it does not specify when.

This has been argued over and over at facilities where LC uses radar for sep. IF you use radar for sep, then you should go to RTF first...

7110.65 1-2-5.d.
d. Paragraphs/sections annotated with EN ROUTE, OCEANIC, or TERMINAL are only to be applied by the designated type facility. When they are not so designated, the paragraphs/sections apply to all types of facilities (en route, oceanic, and terminal).


The rules in the 7110.65 apply to all, regardless of the position they are working, unless the rule states otherwise.

If it says TERMINAL- then that rule only applies to controllers at a terminal facility. So what exactly is a TERMINAL facility? It would be nice to have that defined...

The 4-miles rule, 7110.65 5-5-4.f. shows TERMINAL- So I think the case can be made that tower positions are also responsible since they are not in an ENROUTE or oceanic facility.

The question should be are you required to use radar to separate when working LC at your facility?

If so, then you need the 4 miles (large crosses threshold), and trying to claim you don't cause your in the tower may not get you very far with AOV.

The only time you need 4 miles for a small behind a large is when the large crosses the landing threshold. You can have 3 miles prior to that point, just not at the point where the large crosses the threshold.

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Your friendly neighborhood Lawn Gnome

Should is def the right word to use... but we're talking about the FAA here... haha.

Okay, you can believe what you want about the tower displays. I only cerified those thing for 30+ years. Plus, I was on the team for STARS and ACD that wrote the certification requirements when the systems were under developement. There are no parameters that specify whether a display is certifiable for separation or advisory. Only that that display meets certain defined specifications.

NO TOWER DISPLAYS ARE CERTIFIABLE FOR AIRCRAFT SEPARATION.

As to how tower displays are used, I understand that they might be used many places for separation, but that does not mean they are being used correctly. If an ATC were to have a separation incident while using a tower display, the FAA would not stand behind the ATC. The display specifications DO NOT support it.

So, do what you want, you are the one going out on a limb here.

Dale

What about the TRACABs or LRACs...are their tower displays certified for separation? We have 5 STARS displays in our tower, 3 of them have their own position symbol assigned. We take handoffs, pointoffs, and also provide separation on final as well as separation within our class B between other aircraft.

We have had a few controllers get pinned with Operational Errors because they didn't properly separate our departure from a TRACONs aircraft passing by our airspace.

I'm just curious about the whole thing....can we get away with all this stuff because at one point we were considered a TRACAB and I think now we are called an LRAC if there is such thing.

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Your friendly neighborhood Lawn Gnome

Dale

Sorry to disagree, but using radar separation, in the tower cab, for separation services, via that tower display is REQUIRED and mandated in the local SOP's of many towers/TRACONS in the country. You can go on the FAA national SOP and LOA repository and read them yourself if you have a logon.

There are procedures for when you can/can't combine TRACON to the tower and work aircraft from there. Procedures for how to remap the ETVS for configuration to the tower cab when working TRACON in the tower. We're not just talking about working guys in the pattern. We're talking about the entire class c airspace.

So basically your saying that they are all working radar with uncertified equipment and without FAA approval. I think not.

Call any of the up/downs, and ask them if they combine TRACON to the tower, and work radar in the tower. I'm 100% sure they are working radar in the tower, with FAA approval, per their local procedures, and would be SHOCKED to learn they can't do it legally.

Maybe I'm wrong though.

Dale, what about the displays/scopes in the TRACON, do you know, are there certification standards for those to allow ATC to use them for separation services or is it the same as the tower displays, they just have to meet certain defined specifications?

Okay, this has been a point of contention between Airway Facilities and Air Traffic for years. We have fought on this issue at the national level time and time again.

Air Traffic, national, says you can use them for separation, Airway Facilities, national, says they are not designed/certified for separation. Airway Facilities in the field doesn't care. All they do is certify based on parameters developed by the manufacturer and the program office. If pushed, in a court of law, I have no doubt that Airway Facilities would win the debate that Air Traffic is using these displays beyond their designed parameters and intent.

When we were debating the issue on STARS and ACD (same display on both systems, Lockheed bought them from Raytheon), even the NATCA representatives on the team, after a long discussion, came to the conclusion that the displays are not designed nor are they certifiable for separation. That came from Raytheon and Program Office engineers on the STARS team. Also, the NATCA Representatives did not like the STARS tower display because it presented a display with a usable area that was less than that available on a DBRITE, making it even worse for providing separation.

So, you guys do what you want, I stand by my statement that these displays are not certifiable for separation. They were never designed/intended to be used this way.

Dale, what about the displays/scopes in the TRACON, do you know, are there certification standards for those to allow ATC to use them for separation services or is it the same as the tower displays, they just have to meet certain defined specifications?

Does AF CERTIFY the displays/scopes in the TRACON?

The TRACON displays are certified to defined specifications also, but the "separation services" are in the design of the display, not the certification. AF does not certify for or against how a display is used, they certify that that display is capable of providing it's designed parameters. AF does not care what SOP's or LOA's AT comes up with. As long as a tech is certifying to the designed specifications, AF, and the tech, are off the hook.

The ARTS scopes are 21" round crt's, while STARS and ACD use a 20'" X 20" square (1:1 aspect ratio, 28.3" diagonal) CRT for the TRACON. DBRITE has a 16" round CRT, while STARS and ACD have a 21" diagonal LCD display with a 4:3 aspect ratio. That figures out to a screen that is about 16.8" wide by 12.6" high rectangle (not all of this is usable).

Because STARS and ARTS present a square data area, you only get an equivalent usable area of 12.6" X 12.6" square (1:1 aspect ratio, 17.8" diagonal). Even without taking into account the lack of designed in resolution and bandwidth needed for separation, that is lacking in the tower displays, the size was deemed to small for separation purposes.

So, now while you as an ATC may be off the hook because the AT organization is requiring you to use equipment that was not designed to do the job required, that certainly does not absolve either the FAA nor the AT organization. And believe me, they cannot plead ignorance.