Clip4
Touchdown! Greaser!
With the exception of TRSAs shown on sectionals, what FAA document allows the pilot to determine if a Class D tower has radar?
Class D airports and radar
- Thread starter Clip4
- Start date
spiderweb
Final Approach
- Joined
- Feb 22, 2005
- Messages
- 9,488
- Display Name
Display name:
Ben
You can always call.
poadeleted20
Deleted
- Joined
- Apr 8, 2005
- Messages
- 31,250
I'm not sure there is anything in the standard pilot-accessible pubs (VFR/IFR charts, A/FD, etc) which will tell you whether a Tower is a radar tower or only visual. I know that BWI has a radar tower, but the circle-R which appears next to the Potomac App/Dep Con lines in the BWI A/FD entry does not appear next to the line for Baltimore Tower.
NoHeat
Final Approach
If you are flying VFR and the tower can advise you of traffic observed on radar, it is a lot more useful to talk to them even when outside their little airspace.
Captain
Final Approach
I would never, in a million years, call tower if I'm just flying by and not entering their airspace. Like they don't have enough stuff to do.
With that said, I guess it's an answer to my question. Thanks.
Direct C51
Pre-takeoff checklist
- Joined
- Apr 9, 2013
- Messages
- 341
- Display Name
Display name:
Direct C51
What about a class D airport without a charted TRSA but still with a TRACON? Florence Regional, KFLO has just that. I was flying through there and got handed off to Florence approach. Why isn't it charted as a TRSA? I know it has had a TRACON for a few years now, and also has not been charted as such for a few years so it isn't a chart update issue.
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
It doesn't have the traffic volume to warrant a TRSA. You'll see a lot of facilities that just have a Class D but yet have an approach facility based there as well. I worked at one in the military where we had a Class D and at the base of the tower was our RATCF providing IFR (stage II) approach control services.
Brad Z
Final Approach
It doesn't have enough traffic to warrant a class C designation. They have been phasing out TSRAs for some time now. It's a vestige of the old pre-lettered airspace days.
roncachamp
Final Approach
The Airport/Facility Directory. Let's use KRST as an example, look under COMMUNICATIONS. There are two circled Rs, the first is unnamed because it's on the field. Minneapolis ARTCC provides radar services when the tower is closed. If an off-field facility provided services when the tower is open that facility would be named. KATW is an example of such a field, radar services are provided by Green Bay approach.
Up to about six years ago sectional charts would show a white R inside a blue circle in the airport data block to indicate ASR on a field without Class B or Class C airspace or a TRSA. These were dropped to reduce clutter.
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
I referring to when the airspace was designated in the first place. However long ago when they started approach services there, you can bet TRSAs were around. Based on their type traffic and traffic volume, they didn't meet the need for a TRSA or an ARSA and definitely not a TCA.
roncachamp
Final Approach
Was traffic volume a criterion for a TRSA? IIRC, the plan way back then was to convert all TRSAs to ARSAs, what is now Class C airspace. AOPA objected to that as ARSAs were to be mandatory while TRSAs were not. So traffic/passenger volume numbers were established to decide which TRSAs became ARSAs and which remained TRSAs.
roncachamp
Final Approach
What TRSAs have been phased out? The only former TRSAs I know of became ARSAs/Class C airspace.
Last edited:
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
Well one of the criteria for designating a C is traffic volume. I wasn't alive when TRSAs were originated but I would think they would also use that for initial designation of a TRSA???
I know plenty of military facilities with approach services that are busier than most TRSAs and some Class Cs and never got above a Class D designation. I guess type of traffic operations had more to do than volume in those cases.
Agreed......
What is stupid is a VERY busy class D airport with 300,000 + commercial passengers each year coming and going . Thousands of GA operations on top of that, a NEW tower as of 10 or so years ago., A radar site 300 feet from the tower and that signal is sent to Salt Lake City 200+ miles away.....
And the tower does NOT have a display in the cab.... They are stuck using Mark 1 eyeballs for separation...
......
Attachments
poadeleted20
Deleted
- Joined
- Apr 8, 2005
- Messages
- 31,250
I would point out that many Class D towers that are not radar towers still have some sort of radar display in their cab which they can use for situational awareness if not for vectoring/separation -- Republic Tower (Farmingdale NY, KFRG) is one example. However, you get no indication of that in any normal pilot-use publication, although when they ask you what you're squawking when you check in, that's a hint.
roncachamp
Final Approach
I was alive when they were created. I do not recall traffic volume being a criterion.
Class C airspace requires an annual instrument operations count of 75,000 at the primary airport, or an annual instrument operations count of 100,000 at the primary and secondary airports, or an annual count of 250,000 enplaned passengers at the primary airport.
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
Yeah, I'm aware of those numbers. I'm also saying that places like Eglin, Cherry Point, Yuma and other bases put up similar numbers but remain a D. Some of these Cs are so slow I wonder how they even get to keep their designation. Someone's padding the count.
roncachamp
Final Approach
What is your source for annual instrument operations and enplaned passengers at these fields?
I spent a year at Laughlin AFB, Class C airspace. Approach served the base and Del Rio International Airport. Del Rio had rather spotty passenger service with Navajos, so not a lot of enplanements or IFR operations there. Laughlin is a UPT base so there was a buttload of traffic but not a lot of it was IFR. I don't see how it ever became Class C.
Another good example is GYY. They will typically issue inbounds or transitions (which they get probably about an equal number on a nice VFR day) squawk codes.
An example of the stealth-circle-R guys is like Reading, PA. They actually run something that sort of works like an approach control that frankly I'd have never noticed if I hadn't already been talking to ATC for FF and got handed off to them.
Another fun anomaly is the weekend warrior TRACONs that pop up around here (Martinsburg). I'm leaving Dulles going west and PCT tells me that I don't have to participate, but the military guys at MRB have a portable facility set up and if I want I can contact them on xxx.xx. It was kind of fun.
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
roncachamp
Final Approach
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
That's because you guys double clicked all arrivals to make it look like you were busy.
Jmcmanna
Pre-takeoff checklist
GRB has an automated traffic count.
Also, they have around 350,000 passenger enplanements per year.
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
Crap. No one uses clickers anymore?
I realize GRB is busy. I was being sarcastic because that's Steven's old stomping grounds.
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
Apparently AOPA believes traffic volume was a criterion for establishing a TRSA.
roncachamp
Final Approach
After nine years at ZAU I never considered myself busy at GRB.
roncachamp
Final Approach
Where?
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
A TRSA is airspace that does not fit the requirements of Class C airspace, but is too busy to be just Class D airspace.
TRSAs are “leftovers” from the previous (pre-1993) airspace clas- sification system. As a general rule, they exist at airports whose traffic load requires enhanced radar service, but that aren’t busy enough to justify Class C airspace.
roncachamp
Final Approach
Where are the numbers?
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
Numbers? Doesn't say anything about numbers. Just says traffic volume is a consideration when it comes to establishing a TRSA.
roncachamp
Final Approach
And how is traffic volume measured?
I don't buy AOPA's bullpoop on that. A TRSA is not some stepping stone between class D and class C. To understand how they come about you have to understand all this predates the alphabet airspace.
Back in the day a control tower didn't indicate CONTROLLED AIRSPACE at all by itself. An airport traffic area was a ring five miles around a tower (and 3000' high) where you had to talk to them. They weren't even charted other than the fact the airport symbol was blue. Many but not all were surrounded with a piece of airspace called a control zone, which was just controlled airspace that touched the ground.
The only higher order airspace were Terminal Control Areas. Essentially these were radar facilities around the nations largest airports. There were Group I and II TCAs, the former being the busiest and requiring encoding transponder and banning student operations. There was also a definition of Group III TCAs but they never actually created those.
TRSAs were essentially areas where a radar approach control facility was established but didn't meet the criteria to create a TCA. It primarily existed for IFR, but created a zone that indicated VFR could play if they wanted. Usually, when there was a TRSA, as today, if you want to land at the primary airport, you'd be well advised to play as the tower in the core ATA (or class D now) would often tell you to go away otherwise.
Later ARSAs were created. Some TRSAs grew up into ARSAs, some didn't. We had a group II TCA in Denver and a TRSA at Colorado Springs. DC had a TCA over DCA, but nothing over IAD and (then Friendship-BAL) BWI. Eventually BWI got an ARSA and IAD got a TRSA. Eventually, they all got subsumed along with ADW into the "Tri-Area TCA."
Now this nonsense didn't fit in with ICAO very well. Of course the FAA disregarded ICAO in a number of ways, but they decided to roll the existing ATAs and CZ's into the class E and D airspace, ARSAs into class C, and TCAs into class B. TRSAs just didn't fit, but rather than abolishing them, they just left them as the were. Of course, the FAA promised, no more uncharted airspace. But they were talking out their rears again. It lasted about six months and then they realized it took a rule making procedure to create controlled airspace rather than just turning on the tower so they went back and effectively put back airport traffic areas.
I'm unaware (Steve? Anyone) of any existing TRSAs that aren't just relics from the pre-alphabet airspace. They're just the ugly child that never grew up into another form of airspace for whatever reason (be it traffic counts, or something else).
Back in the day a control tower didn't indicate CONTROLLED AIRSPACE at all by itself. An airport traffic area was a ring five miles around a tower (and 3000' high) where you had to talk to them. They weren't even charted other than the fact the airport symbol was blue. Many but not all were surrounded with a piece of airspace called a control zone, which was just controlled airspace that touched the ground.
The only higher order airspace were Terminal Control Areas. Essentially these were radar facilities around the nations largest airports. There were Group I and II TCAs, the former being the busiest and requiring encoding transponder and banning student operations. There was also a definition of Group III TCAs but they never actually created those.
TRSAs were essentially areas where a radar approach control facility was established but didn't meet the criteria to create a TCA. It primarily existed for IFR, but created a zone that indicated VFR could play if they wanted. Usually, when there was a TRSA, as today, if you want to land at the primary airport, you'd be well advised to play as the tower in the core ATA (or class D now) would often tell you to go away otherwise.
Later ARSAs were created. Some TRSAs grew up into ARSAs, some didn't. We had a group II TCA in Denver and a TRSA at Colorado Springs. DC had a TCA over DCA, but nothing over IAD and (then Friendship-BAL) BWI. Eventually BWI got an ARSA and IAD got a TRSA. Eventually, they all got subsumed along with ADW into the "Tri-Area TCA."
Now this nonsense didn't fit in with ICAO very well. Of course the FAA disregarded ICAO in a number of ways, but they decided to roll the existing ATAs and CZ's into the class E and D airspace, ARSAs into class C, and TCAs into class B. TRSAs just didn't fit, but rather than abolishing them, they just left them as the were. Of course, the FAA promised, no more uncharted airspace. But they were talking out their rears again. It lasted about six months and then they realized it took a rule making procedure to create controlled airspace rather than just turning on the tower so they went back and effectively put back airport traffic areas.
I'm unaware (Steve? Anyone) of any existing TRSAs that aren't just relics from the pre-alphabet airspace. They're just the ugly child that never grew up into another form of airspace for whatever reason (be it traffic counts, or something else).
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
??? So, because the two airspace classes didn't mention specific numbers on how they designate a TRSA, that means in reality numbers were never used?
Once again:
A TRSA is airspace that does not fit the requirements of Class C airspace, but is too busy to be just Class D airspace.
TRSAs are “leftovers” from the previous (pre-1993) airspace clas- sification system. As a general rule, they exist at airports whose traffic load requires enhanced radar service, but that aren’t busy enough to justify Class C airspace.
Jmcmanna
Pre-takeoff checklist
When I left GRB in 2009, the clickers were just for traffic in the pattern. The arrivals and departure traffic count was done by counting the strips and then by the auto traffic count. No option to cheat.
Once again, it is NOT true. TRSAs are NEVER established anymore. They were never something that grew up from class D airspace.
A more correct statement is "TRSAs are areas of radar service that predate the current class B/C/D airspace that for whatever reason have not been transitioned to another airspace type.
Even traffic itself isn't what makes a class C. You could but 2000 operations a day into a class D airport and if they don't have a radar facility it can NEVER become a class B or C.
The busiest class D airport in the world will certainly never get one (of course it's only that busy for one week a eyar).
VNY has 1100 a day operations making it busier than some class B airports and it's tucked up against the Burbank (360 ops a day) class C and the LAX class B in it's little own class D like it has been since class D's existed.
Last edited:
roncachamp
Final Approach
I believe all existing TRSAs were established prior to the mid 1980s. That's when those that had the numbers became ARSAs. ARSAs became Class C airspace in 1993.
roncachamp
Final Approach
It means the publications you cited are of questionable value to this discussion.
Shepherd
Final Approach
My class "D" has radar.
It's always down for maintenance, but we have radar.
It's always down for maintenance, but we have radar.
- Joined
- Jul 3, 2012
- Messages
- 15,675
- Display Name
Display name:
Velocity173
Didn't say they were established today. I'm talking about when they were originally established (post # 11) years ago before our current airspace classification. I think it's reasonable to assume they used some sort of traffic count to upgrade it from a CZ or not to make it an ARSA. Perhaps they just rolled the dice, I don't know, but the AOPA presentations make sense to me.
Last edited: