TCAS RAs

wilkersk

wilkersk

Pattern Altitude
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KennyW
I recently went to a FAAST seminar on reducing the number of TCAS RAs within the terminal area of a local Class D airport that lies within the Mode C veil of a class B.

One of the "statistics" presented during the presentation was that 60% of these RAs were between TCAS equipped arriving and departing aircraft and other airport traffic, in contact with ATC.

My question is this: what happens when an aircraft in the terminal area receives an RA on an "intruder" aircraft that is simply another aircraft in the pattern?

Its my understanding that Part 121 OpSpecs say that pilots must respond to all RAs. But, how does this jive with ATC? What kind of follow up happens when an RA is issued to an aircraft an IFR clearance within the terminal area?
 
The RA reigns supreme. The crew advises ATC after they have made the avoidance maneuver.
 
So these RAs that are occurring when the "intruder" is another aircraft in the pattern, is it because these aircraft are not where they are supposed to be? Or is it a flaw in the system?
 
Brad Z said:
The RA reigns supreme. The crew advises ATC after they have made the avoidance maneuver.
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And is why there are numerous Airworthiness Directives on them AND EASA member countries have mandated the latest & great software version level that is not required in the USA.
 
The flaw is that the pilot (or ATC) allowed the aircraft to get in the right proximity to cause the alert. I was bopping alone at 10,500 over the Chicago lakeshore (getting services from C90) and watched an MD80 climbing in front of me start to descend. The controller calls out "I just got a TCAS RA" and the controller says "Oh, yeah, there is a Navion up there." I pointed out that I had him continually in sight.

I decided to submit an unsolicited report to the NTSB in case the other pilots felt compelled to make a filing. Figured it would help to have both sides of the story. What I hadn't realized is that the guy who gets those reports knows my wife. She got an email asking if she could possibly go to Oshkosh without scaring some airline pilot out of his wits.
 
I believe their OpSpecs specify to follow the RA unless it's a hazard not to or they have the aircraft visually.

At PDK a few months ago I departed to the north at 2,500 ft. I picked up a target on TCAD about 10 o'clock and 2 miles out of 3,000 ft converging. ATC gave me traffic (Beechjet) on it and I replied "visual" on the traffic. She then then gave traffic on me to the Beechjet. I saw the aircraft turn right and went behind our tail 300 ft above us and 1/2 mile. The pilot replied that he had to respond to an RA because he didn't have us in sight. She simply replied with a roger and told him that I had him in sight. Pilot actually sounded a bit agitated about how close we were.
 
At my airline, we're required to follow the RA, even if it conflicts with ATC's instruction. Both pilots are then required to submit an ASAP report detailing the event. This report, in addition to going to my company, goes to the FAA.

I get about 2 per year.
 
flyingron said:
I guess standard phraseology is out of the question.
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I don't remember my exact verbiage. I suppose it was probably "tally ho" but it was too long ago to remember.
 
Back when I was based at Chesterfield Co. Airport (FCI, or now known as Richmond Exec, barf), Potomac Approach would bring RIC runway 2 inbound aircraft in from Flat Rock VOR (FAK) right over FCI. After getting the inbounds past the antennas NW of FCI, controllers would descend them down to 2,000 for the visual approach. Oh course this happened to be just NW of FCI, so if an aircraft departing runway 33 at FCI climbed at anything faster than a C-150, it would set off an RA to the opposing inbound descending traffic to Richmond if the timing was just right. I think they finally figured it out after enough alerts (as well as at least one ASRS from me).

I imagine this is common at other satellite airports with arrival corridors overhead.
 
Velocity173 said:
Please, all the cool pilots use either Tally or if you're old school Tally Ho!
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I was Navy enlisted aircrew for 16 years. I learned all the common terminology in use at the time. "Tally-ho" , and "Roger" were common usage. I get crap from some other pilots for using those terms nowadays. But, every once in awhile, they slip out.

The one I'm trying to get out of the habit of saying is "With you at -". That is for sure a waste of words.
 
Brad Z said:
Back when I was based at Chesterfield Co. Airport (FCI, or now known as Richmond Exec, barf), Potomac Approach would bring RIC runway 2 inbound aircraft in from Flat Rock VOR (FAK) right over FCI. After getting the inbounds past the antennas NW of FCI, controllers would descend them down to 2,000 for the visual approach. Oh course this happened to be just NW of FCI, so if an aircraft departing runway 33 at FCI climbed at anything faster than a C-150, it would set off an RA to the opposing inbound descending traffic to Richmond if the timing was just right. I think they finally figured it out after enough alerts (as well as at least one ASRS from me).

I imagine this is common at other satellite airports with arrival corridors overhead.
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Oddly enough, the number of RA "intruders" from aircraft going into or out of nearby airports is historically pretty small compared to the RAs from other aircraft arriving at the subject airport, according to the data shown.
 
kayoh190 said:
At my airline, we're required to follow the RA, even if it conflicts with ATC's instruction. Both pilots are then required to submit an ASAP report detailing the event. This report, in addition to going to my company, goes to the FAA.

I get about 2 per year.
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I also get a few per year. We are not required to report them except in RVSM airspace and I have never had one in RVSM airspace. The most common area for us to get them is below Class B going in to a feeder airport. As others have said, you are supposed to follow the RA even if contrary to an ATC instruction. All you need to do is tell them that you are responding to one.
 
Pilots with TCAS often don't seem to understand that it's perfectly legal for "intruder" aircraft to be close enough to trigger an RA under many circumstances. Since those circumstances involve VMC conditions, it's also generally preventable by keeping TCAS in your instrument scan and keeping a good visual scan out the windshield.

Very seldom is a jet overtaken from behind by a Navion.:rolleyes:

I've only had two RA's that I can remember...one was a VFR aircraft 200 feet below me when I was IMC on an approach. The other was a Beaver taking off on the parallel runway...but I had him in sight, and our manual allowed us to ignore the RA If we could see and avoid the traffic.
 
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yes,a good majority of ra's are in class b. most are cause by the design of the tcas system. tcas takes into account the rate at which the targets are closing. In a lot of class B areas, DFW is a prime example, outbound traffic is climbing to an altitude that is 1000 feet below what the arriving traffic is decending to. so, if you are decending at a good rate, and a fast climber, like a light 757 is climbing and you are going to cross directly above him, you will get an RA because of the rate even though you are both leveling out 1000 apart. however, those type of RA's are just "monitor vertical speed" warnings.

bob burns
 
wilkersk said:
Its my understanding that Part 121 OpSpecs say that pilots must respond to all RAs. But, how does this jive with ATC? What kind of follow up happens when an RA is issued to an aircraft an IFR clearance within the terminal area?
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Which "OpSpec" says that? :dunno:
 
RotorAndWing said:
Which "OpSpec" says that? :dunno:
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Thanks. I was about to ask for the specifics on that as well. We don't have it and I would like to ensure that I can respond to an RA properly. Will probably be waiting a while until we get an answer. Got to love the experts here.
 
There have been a few RAs for traffic inbound to nearby Portland (Oregon) Int'l, triggered by traffic from our airport.

Our airport is an uncontrolled field in its own Class D, the only such arrangement in the country. The Class D is a cutout from the surface area of the KPDX Class C, up to 1100'. KVUO is under the approach to KPDX 10L, about two miles from the threshhold, and the runway is aligned almost the same (8/26). If one of our guys takes off from 26 while a jet is approaching KPDX 10L/R, it can trigger an RA even if he's entirely legal within the Class D and the jet is in Class C. Even traffic on downwind for 8 at KVUO can do the deed.

A few years ago some middle management FAA guy at Renton tried to implement an RA-proof procedure where KPDX tower would hold departing KVUO traffic on the ground, and keep arriving traffic from entering the Class D, any time KPDX traffic was within 8 miles inbound to 10L/R. Everybody, including KPDX controllers, local media, city governments on both sides of the Columbia, and all four Senators from Washington and Oregon, opposed the plan, and it was quietly shelved.

Since then, KVUO traffic works with KPDX tower to avoid possible RA scenarios, and it seems to be working.

VUO_sectional_2015.jpg
 
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If it's uncontrolled, who are you supposed to talk to for it to be legal to enter the class D?
 
StinkBug said:
If it's uncontrolled, who are you supposed to talk to for it to be legal to enter the class D?
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Note the box on the chart that says "Pearson Fld Class D Ctc VUO Advisory 119.0." Arrivals and departures are required to contact "Pearson Advisory" on the CTAF, 119.0. Pearson Advisory is a controller in the Portland Tower, whose job is to issue wake turbulence advisories and traffic, on a workload-permitting basis. It also serves as VUO's Clearance Delivery for IFR departures. He/she can't see Pearson from the tower and does not sequence VFR traffic or issue takeoff or landing clearances.

The dialogue goes like this:
Pilot: "Pearson Advisory, Bugsmasher 123, inbound from Vancouver Lake with the [ASOS] weather."

Pearson Advisory: "Bugsmasher 123, Pearson Advisory. Remain clear of Class Charlie airspace. Portland arrivals landing from the west, caution wake turbulence. Traffic is a Boeing 737 on a five mile final for Portland, one aircraft reported in the Pearson pattern."
​
The spiel is similar for departures. After acknowledging the advisory, the Pearson pilot makes his pattern calls, just like for any other uncontrolled field, on the same frequency. The controller is usually not heard from again, though he/she may speak up if a new traffic/wake turbulence situation arises.

It actually works quite well. Pearson Advisory also coordinates requests for transition through the Class C for eastbound and southbound VFR departures, then hands off to Portland Tower.
 
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Interesting. I totally missed the advisory box there, was just looking at the info block for VUO. Wonder how many people miss it as well when flying there. I suppose if they are making proper calls it wont matter though, as they should be making their first call outside the area and will be on the same channel anyways.
 
MauleSkinner said:
Very seldom is a jet overtaken from behind by a Navion.:rolleyes:
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The aircraft that got the RA *NEVER* saw us.

We weren't overtaking him, we were converging at pretty much right angles and he was climbing at the time.
 
I'm required to comply with RAs. Usually fill out some paperwork on the Air Force side of things, but don't think it usually goes further than that.
 
flyingron said:
The aircraft that got the RA *NEVER* saw us.

We weren't overtaking him, we were converging at pretty much right angles and he was climbing at the time.
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"Pretty much right angles"...he was climbing at probably 250 KIAS...If you were indicating 120 KIAS, that would have put you 30 degrees off his nose....WELL within visual angle for him.

His TCAS should have also given him plenty of notice before the RA to look for you as well.
 
MauleSkinner said:
"Pretty much right angles"...he was climbing at probably 250 KIAS...If you were indicating 120 KIAS, that would have put you 30 degrees off his nose....WELL within visual angle for him.

His TCAS should have also given him plenty of notice before the RA to look for you as well.
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He may have been looking, but he didn't see us. An MD80 is a whole lot easier to spot than a Navion.
 
Im not an expert on the subject, I'm just a dumb "weekend warrior" trying to improve my knowledge of flight operations in general. That's why I said, "it was my understanding," in the OP. But, I found this with a cursory Google search:

http://fsims.faa.gov/wdocs/8900.1/v03 tech admin/chapter 18/03_018_005_chg_153a.htm
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OPSPEC/MSPEC/LOA C052, STRAIGHT-IN NON-PRECISION, APV, AND CATEGORY I PRECISION APPROACH AND LANDING MINIMA —ALL AIRPORTS.
K
b) ATC Breakout Maneuver Command to Turn and/or Descend, Climb, or Maintain Altitude. The flightcrew must immediately follow the final monitor controller’s vertical (climb/descend/maintain altitude) and horizontal (turn) commands. If the flightcrew is operating the TCAS in the traffic advisory (TA)/Resolution Advisory (RA) mode and receives a TCAS RA at any time while following the final monitor controller’s command, the flightcrew will simultaneously continue to turn to the controller’s assigned heading and follow the vertical guidance provided by the TCAS RA.
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Also, I got the impression that the whole reason for having the FAAST seminar that I attended on the subject was that these RAs in the terminal area were causing problems for ATC.
 
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unsafervguy said:
ok, mr exact wording. it my not be an opspec, however it under the operating cert of the airline, it is in the manuals approved by the FAA, overseen by the FAA POI and required to be followed to the letter. so what fricking difference does it make if it not exactly an opespec. it is still strictly required.
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The term "OpSpec" gets thrown around on aviation boards a lot, problem is most don't even understand what they actually are.

For someone working for an air carrier not to understand what an OpSpec is, what it means and how it applies to the operation is weak. OpSpecs are covered in basic indoc at all air carriers (135 and 121).
 
Rotor&Wing
Generic question with no agenda...and you can answer by PM if you wish....

Do you work for Cathay?
 
RotorAndWing said:
The term "OpSpec" gets thrown around on aviation boards a lot, problem is most don't even understand what they actually are.

For someone working for an air carrier not to understand what an OpSpec is, what it means and how it applies to the operation is weak. OpSpecs are covered in basic indoc at all air carriers (135 and 121).
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The thing is that most people on this board don't work for air carriers. I notice when OpSpec is used incorrectly too, and I'll even sometimes correct people as a teaching moment, but I don't expect people who have never worked for an air carrier to automatically understand the difference between an OpSpec and the Operations Manual or SOPs.
 
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Everskyward said:
The thing is that most people on this board don't work for air carriers. I notice when OpSpec is used incorrectly too, and I'll even sometimes correct people as a teaching moment, but I don't expect people who have never worked for an air carrier to automatically understand the difference between an OpSpec and the Operations Manual or SOPs.
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Google is a wonderful tool.

If I read something I don't understand, I take the time to research it. Too often on forums people begin parroting terms around without even a basic understanding of the term.
 
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