Circuit flying with a jet and the use of TCAS
Thread Starter
Join Date: Apr 2007
Location: Benelux
Posts: 111
Likes: 0
Received 0 Likes
on
0 Posts
Circuit flying with a jet and the use of TCAS
If you are doing touch and goes in a jet (or turbo prop/atr kind of plane) with several small planes in the circuit as well, what would you select regarding TCAS? TA/RA, TA only or ALT only?
You are probably outperforming everybody and cessna/pipers are turning in a much more tight circuit. So while you are on final the ones on downwind will be "pretty" close.
I would probably go for ALT only and leave the seperation to the tower controller.
You are probably outperforming everybody and cessna/pipers are turning in a much more tight circuit. So while you are on final the ones on downwind will be "pretty" close.
I would probably go for ALT only and leave the seperation to the tower controller.
Join Date: Apr 2002
Location: East and West Mids UK
Posts: 108
Likes: 0
Received 0 Likes
on
0 Posts
It is SOP to select TA/RA at our outfit. Having said that, our installation inhibits RA commands below a certain alititude anyhow (exact figure escapes me - but around circuit height), and TA only still gives us situational awareness of where everyone else is on the TCAS display along with altitude info from those squawking mode C. Quite useful if there is any other circuit traffic.
Yes we (757/767) certainly do outperform the little guys and they will need to give us at least 8 miles before being allowed to follow us down an approach. ATC give them plenty of help and tend to offer commercial (jet/tp) traffic priority.
We tend to choose airfields where there is relatively little GA traffic too. I always feel for any that is there as it tends to spend a lot of time doing orbits somewhere remote while waiting for the wake to dissipate.
Hope this helps.
Yes we (757/767) certainly do outperform the little guys and they will need to give us at least 8 miles before being allowed to follow us down an approach. ATC give them plenty of help and tend to offer commercial (jet/tp) traffic priority.
We tend to choose airfields where there is relatively little GA traffic too. I always feel for any that is there as it tends to spend a lot of time doing orbits somewhere remote while waiting for the wake to dissipate.
Hope this helps.
Join Date: Jul 2006
Location: USA
Posts: 451
Likes: 0
Received 0 Likes
on
0 Posts
Good question....
Airbus, speaking for the U.S. FAA, says the FAA 'recommends' that the "RA" function be inhibited....that is, place the selector ot TA only. The logic is that unwarranted resolution advisories will not occur. This recommendation is for pattern flying...or SIDs and STARs where air traffic is such that unwarranted RAs might occur...."nuisance RAs".
(Off hand, I can't remember the exact FCOM wording....)
Personally, I know of no major carrier that follows this recommendation. I certainly don't. In my mind, and in the logic of my company's SOP, any RA is a real threat and should be delt with accordingly. The versions of TCAS
are now refined, in my opinion, that there are few, if any, 'nuisance RAs'.
Fly safe,
PantLoad
(Off hand, I can't remember the exact FCOM wording....)
Personally, I know of no major carrier that follows this recommendation. I certainly don't. In my mind, and in the logic of my company's SOP, any RA is a real threat and should be delt with accordingly. The versions of TCAS
are now refined, in my opinion, that there are few, if any, 'nuisance RAs'.
Fly safe,
PantLoad
Thread Starter
Join Date: Apr 2007
Location: Benelux
Posts: 111
Likes: 0
Received 0 Likes
on
0 Posts
The 757 is of course already quite big. To be honest I was more thinking about 737s and large biz jets.
On the 737 RAs are also suppressed below a certain altitude.
If you do decide to have one of the modes running you can expect to have a TA every now and then wouldn't you?
On the 737 RAs are also suppressed below a certain altitude.
If you do decide to have one of the modes running you can expect to have a TA every now and then wouldn't you?
Join Date: Sep 2003
Location: uk
Posts: 361
Likes: 0
Received 0 Likes
on
0 Posts
Did my training at Seville and we had TA/RA selected, we knew that we would only get TA's tho, think 1000' RadAlt is the cutoff for RA's.
In my circiuts alone I had four TA's and there were six of us over two days,
Best to have what your company SOP's say.
In my circiuts alone I had four TA's and there were six of us over two days,
Best to have what your company SOP's say.
Ex-USAF, we kept it in TA/RA mode and flew lots of pattern work. The TCAS saved me from a few frights, too. I would leave it in TA/RA mode.
GF
GF
Warning Toxic!
Disgusted of Tunbridge
Disgusted of Tunbridge
Join Date: Jan 2005
Location: Hampshire, UK
Posts: 4,011
Likes: 0
Received 0 Likes
on
0 Posts
I've never known it to work sharing circuits and bumps with light aircraft. Jets fly a very defined circuit, you cannot share the circuit with small ones flying at 100mph less on tighter patterns. It's asking for disaster, and they cannot get in front of you nor follow you in. It just doesn't work- that is why jets go long distances sometimes to avoid light aircraft congestion.
Join Date: Apr 2008
Location: Benelux
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
impossible to mix?
I beg to disagree with the "fact" that it would be impossible and/or even dangerous to mix slow moving circuit traffic (mainly light category) with either medium or heavy traffic if executed under strict ATC control, which would be ofcourse only applicable to controlled (airspace "C"), so at airports with a mixture of IFR and VFR traffic.
I'm an ATCO at a regional airport with exactly that kind of traffic and have been doing this kind of "traffic control" for more than 25 years, and in this period i ofcourse have met situations in respect to this mixture of traffic for which second thoughts would have been neccessary, in retrospect, but as indicated above, if executed firmly and based on altitudes agreed upon for all parties involved, it is possible to accomodate a certain mixture of traffic, and local procedures lead down in regulations would enhance this.
Ofcourse at any time in such an environment it is good judgement to "extract" some of the participants from the circuit flying if it is crowded in such a way that safety would be infringed, so mostly (often) "the smaller and slower and less experienced" are at a certain point in time ordered to make a full stop or continue their circuit training elsewhere.
Also "flow" regulations in this respect are often used and ofcourse weather conditions could be a reason to restrict the mixture of traffic, let alone (VFR) circuit training all together.
But aside from weather conditions, at an airport with several training schools, you tend to get a mixture of VFR circuit traffic and IFR straight-in trainers.
Now comes in the topic at hand, the TCAS procedures laid down with an airline or FBO, and one will be obliged to anticipate to TA's or RA's, which would be ofcourse legal and mandatory, but it surely could be a problem (practically and judicially) if the RA mode would be used in such an environment, making a possible (counter productive) action neccessary by the involved crew as apposed to just using the TA mode, as already mentioned by some, in order to get a proper "situational awareness".
Just my two pennies.............
I'm an ATCO at a regional airport with exactly that kind of traffic and have been doing this kind of "traffic control" for more than 25 years, and in this period i ofcourse have met situations in respect to this mixture of traffic for which second thoughts would have been neccessary, in retrospect, but as indicated above, if executed firmly and based on altitudes agreed upon for all parties involved, it is possible to accomodate a certain mixture of traffic, and local procedures lead down in regulations would enhance this.
Ofcourse at any time in such an environment it is good judgement to "extract" some of the participants from the circuit flying if it is crowded in such a way that safety would be infringed, so mostly (often) "the smaller and slower and less experienced" are at a certain point in time ordered to make a full stop or continue their circuit training elsewhere.
Also "flow" regulations in this respect are often used and ofcourse weather conditions could be a reason to restrict the mixture of traffic, let alone (VFR) circuit training all together.
But aside from weather conditions, at an airport with several training schools, you tend to get a mixture of VFR circuit traffic and IFR straight-in trainers.
Now comes in the topic at hand, the TCAS procedures laid down with an airline or FBO, and one will be obliged to anticipate to TA's or RA's, which would be ofcourse legal and mandatory, but it surely could be a problem (practically and judicially) if the RA mode would be used in such an environment, making a possible (counter productive) action neccessary by the involved crew as apposed to just using the TA mode, as already mentioned by some, in order to get a proper "situational awareness".
Just my two pennies.............
Warning Toxic!
Disgusted of Tunbridge
Disgusted of Tunbridge
Join Date: Jan 2005
Location: Hampshire, UK
Posts: 4,011
Likes: 0
Received 0 Likes
on
0 Posts
The original question was concerning mixing slow light circuit traffic with jet circuits as well:
not light circuits with incoming or outgoing heavy IFRs as you answered:
IFR straight-ins or outs do work, but not both light circuit types and jets trying to do circuits together. It is a frightening experience in jets when you are constantly unable to see the light traffic and trying to fly a high pressure, tightly controlled circuit pattern. I've never known it work yet- jets are too fast to mix with them. Constantly having to widen the circuit or extend downwind messes up the training element. I've even had go-arounds in a visual straight-in turboprop behind unbelievably slow Cessnas that have appeared to apparently stop in mid-air. They just don't mix.
If you are doing touch and goes in a jet (or turbo prop/atr kind of plane) with several small planes in the circuit as well, what would you select regarding TCAS? TA/RA, TA only or ALT only?
I beg to disagree with the "fact" that it would be impossible and/or even dangerous to mix slow moving circuit traffic (mainly light category) with either medium or heavy traffic if executed under strict ATC control, which would be ofcourse only applicable to controlled (airspace "C"), so at airports with a mixture of IFR and VFR traffic........But aside from weather conditions, at an airport with several training schools, you tend to get a mixture of VFR circuit traffic and IFR straight-in trainers.
Join Date: Apr 2008
Location: Benelux
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
mixing traffic
I do agree it is a complicated situation when having jets and smaller a/c, mostly piston driven, together in a visual circuit, and that is what i was trying to say....on top of the existing circuit situation you might ALSO have the mentioned straight-in approaches.
So on the TA/RA subject these indeed two different situations would have the same impact.
I also agree that just this mixture of traffic could be counterproductive for jet crews because of what you said, concerning e.g.extended downwind legs or even "three-sixties" in the circuit, but i want to stress the fact that this would only be possible at controlled airports, where one has to accept a probably longer line-up in order to have separation so to rely on strict atc instructions is a fact.
I also indicated that in order to be able to use this mixture safely, a kind of flow system has to be used on behalf of all parties involved.
In general ofcourse, operators with (large) jets would be better "served" at airports without smaller, slower traffic, in order to have their objectives meet.
So on the TA/RA subject these indeed two different situations would have the same impact.
I also agree that just this mixture of traffic could be counterproductive for jet crews because of what you said, concerning e.g.extended downwind legs or even "three-sixties" in the circuit, but i want to stress the fact that this would only be possible at controlled airports, where one has to accept a probably longer line-up in order to have separation so to rely on strict atc instructions is a fact.
I also indicated that in order to be able to use this mixture safely, a kind of flow system has to be used on behalf of all parties involved.
In general ofcourse, operators with (large) jets would be better "served" at airports without smaller, slower traffic, in order to have their objectives meet.
Warning Toxic!
Disgusted of Tunbridge
Disgusted of Tunbridge
Join Date: Jan 2005
Location: Hampshire, UK
Posts: 4,011
Likes: 0
Received 0 Likes
on
0 Posts
Yes....that's why I said
In the days when simulators weren't so good, it was a regular thing to fly a 4 engine heavy jet up to Prestwick, Machrihanish or France from London with about 20 pilots and a couple of instructors and just spend the day in a (non-noise conscious) circuit banging around and around on touch and goes to the heart's content, each pilot having about 3 circuits, and a refuelling session midway. All swept away in the mists of time now- simulators do it just as well. It was a great disruption whenever a light aeroplane appeared in the circuit, however efficient the ATC control- you just cannot mix the two.
It just doesn't work- that is why jets go long distances sometimes to avoid light aircraft congestion.
Join Date: Apr 2008
Location: Benelux
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
excuse me but "you're NOT saying it, you're just pressing on with your opinion", just as i expressed my opinion on the subject, but i don't have to be commented on just my opinion which has as much merit as yours.
In all we do agree, but as you indicated the days of bumping around at far off airports either in Europe or elsewhere are less, but they still are being used at one time or another in the final training process.
The mixture of different categories of aircraft just to have them practice circuit flying at the same time should ofcourse be avoided if possible.
In all we do agree, but as you indicated the days of bumping around at far off airports either in Europe or elsewhere are less, but they still are being used at one time or another in the final training process.
The mixture of different categories of aircraft just to have them practice circuit flying at the same time should ofcourse be avoided if possible.
While pounding the circuit with heavy equipment we leave TCAS on TA/RA. You see, you will never, ever see any of our aeroplanes sharing circuit with anyone else. Straight-ins and take-offs can be mixed with circuits, anything else just can't.
