Traffic pattern question: do you ever...

Hilarious! As if an Air Force ANG reg applies to everywhere huh?
By Order of the Secretary of the Air Force:
"This instruction implements AFPD 13-2, Air Traffic Control, Airspace, Airfield, and Range Management. It applies to all US Air Force (USAF), Air National Guard (ANG) and Air Force Reserve Command (AFRC) organizations (to include contracted locations) that operate or administer functions in facilities in the airfield operations flight (AOF)."​

I just grabbed the first convenient copy I could find.

G'night guys. You two can console each other, I'm going to bed.

dtuuri
 
By Order of the Secretary of the Air Force:
"This instruction implements AFPD 13-2, Air Traffic Control, Airspace, Airfield, and Range Management. It applies to all US Air Force (USAF), Air National Guard (ANG) and Air Force Reserve Command (AFRC) organizations (to include contracted locations) that operate or administer functions in facilities in the airfield operations flight (AOF)."​
I just grabbed the first convenient copy I could find.

G'night guys. You two can console each other, I'm going to bed.

dtuuri
The purpose and intent of that requirement is to protect aircraft in the overhead from departing aircraft. This is normally done by having departing aircraft cross the departure end of the runway at or below the overhead pattern altitude minus 500 ft.
 
By Order of the Secretary of the Air Force:
"This instruction implements AFPD 13-2, Air Traffic Control, Airspace, Airfield, and Range Management. It applies to all US Air Force (USAF), Air National Guard (ANG) and Air Force Reserve Command (AFRC) organizations (to include contracted locations) that operate or administer functions in facilities in the airfield operations flight (AOF)."
I just grabbed the first convenient copy I could find.

G'night guys. You two can console each other, I'm going to bed.

dtuuri

Yeah Secretary of The Air Force makes FAA policy too I suppose. And as always with your selective reading notice how it doesn't say anything about punblishing a diagram. I already said it just so happens that our base mirrored that reg so not sure where you are going with this??? Can't speak for the numerous other bases in the Navy, Marines, Army or civilian for that matter.

Another thing that shoots down your having to comply with the AIM pattern. I've never seen a 360 power off approach pattern published for an airport. Must be illegal I guess?

And "Doug" and I don't need to console one another. I suppose all of us on this thread need to though because all of us are wrong and you are right. I noticed this trend on other postings of yours. You never post anything positive or give any advice to help out people starting an aviation career. You simply try and belittle them with harsh words to their opinions with no tact at all. Then the whole thread comes down on you and you just try and fight your small part of the battle that you think you can win and ignore the facts that people keep bringing up.

I didn't join this forum to compare aviation knowledge with others. No one on here has an aviation library in their brain. Everything can be googled (as you demonstrated) and regurgitated to make it seem like someone is an expert. Aviation procedures, especially non-regulated ones aren't black and white. That leaves us as PICs the ability to decide for ourselves the best way to handle the outcome. Every persons opinion on here on how to handle a pattern entry is correct. I don't recall anyone stating anything contrary to FAR parts 91, 93 or 97.

This thread has run its course for me.
 
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I fly an RV..

MANDATORY pattern entry for us is the inverted overhead break.
 
You got more red herrings than a fish market, Mcfly. I never said a 'diagram' must be published at military fields, but I bet it makes it a lot easier to communicate if one is used. I posted one to illustrate the overhead maneuver and show that where they exist they are 'developed' by management. Follow the bouncing ball:

It's not ad-hoc when it's 'established' or 'developed', like here for instance:

Your inclusion of a diagram of the overhead just shows how little you know about military airfields. ... Some airfields publish altitudes for it and some don't.
So, I offered up proof that overhead patterns must be 'developed' at USAF bases and they must be published. Never did I say there must be a 'depiction' of it, although it would probably be a good idea to include one.
"AFI 13-204V3_ANGSUP_I 20 May 2011

9.7. Protection of 360 Overhead Pattern. Locations that use the overhead pattern must develop local procedures and coordinate ATC/aircrew requirements to protect the overhead pattern. Procedures and coordination requirements must be published in an LOP and AOI."
Next, you imply something else I never said: That this was an ANG reg only and wouldn't apply "everywhere" else. Since we were talking about military installations, I offered up proof that it did also apply to non-ANG USAF bases:
As if an Air Force ANG reg applies to everywhere huh?

By Order of the Secretary of the Air Force:
"This instruction implements AFPD 13-2, Air Traffic Control, Airspace, Airfield, and Range Management. It applies to all US Air Force (USAF), Air National Guard (ANG) and Air Force Reserve Command (AFRC) organizations..."​
Then you twisted that into a red herring:
Yeah Secretary of The Air Force makes FAA policy too I suppose.

I noticed this trend on other postings of yours. You never post anything positive or give any advice to help out people starting an aviation career.
When people who should know better, but don't, post erroneous information, I weigh in to help the newbies sort things out. In that respect, I noticed a trend with your posts too.

You simply try and belittle them with harsh words to their opinions with no tact at all.
Just another red herring.


dtuuri
 
The purpose and intent of that requirement is to protect aircraft in the overhead from departing aircraft. This is normally done by having departing aircraft cross the departure end of the runway at or below the overhead pattern altitude minus 500 ft.
Welcome Kent! :) I hope you would agree that the purpose of the 'publishing' requirement is immaterial. The point is, overhead patterns are developed.

Further along in the reg it says:
"PROCEDURES FOR ESTABLISHING VFR FLYING AREAS AND TRAFFIC PATTERNS
12.1. VFR Traffic Patterns:
12.1.1. When designing traffic patterns, be sure that:
12.1.1.1. They conform to the requirements of paragraphs 12.2 and 12.3 below except when safety or noise problems require adjustments.
12.2. VFR Traffic Pattern Types:
12.2.1. Establish rectangular and overhead patterns at each USAF airfield...
12.2.3. Bases may establish an additional rectangular pattern for light aircraft. This pattern provides adequate separation from normal rectangular and overhead pattern traffic."


dtuuri
 
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It would seem the "overhead" was developed to recover tactical aircraft, that may low on fuel, quickly and to also minimize exposure to enemy ground fire. When used by the military, the overhead is conducted in a controlled environment .

To do this maneuver at a non towered civilian field I would think would come under the careless and reckless reg. While the AIM is not regulatory, non compliance with its' recommendations is used to hammer pilots in enforcement actions.
 
It would seem the "overhead" was developed to recover tactical aircraft, that may low on fuel, quickly and to also minimize exposure to enemy ground fire. When used by the military, the overhead is conducted in a controlled environment .

To do this maneuver at a non towered civilian field I would think would come under the careless and reckless reg. While the AIM is not regulatory, non compliance with its' recommendations is used to hammer pilots in enforcement actions.

Here we go again...
 
I hope you would agree that the purpose of the 'publishing' requirement is immaterial.

The purpose is quite material, particularly given that you've tried to restrict the conversation already to uncontrolled public use civil airfields, and are not calling on whatever documents you can google up from military airfields.

Would you prefer to have a conversation regarding military air operations, and is that relevant to the original question that began the thread?

We're talking about a midfield crosswind entry into a normal traffic pattern. This seems rather complicated to you.

It would seem the "overhead" was developed to recover tactical aircraft, that may low on fuel, quickly and to also minimize exposure to enemy ground fire. When used by the military, the overhead is conducted in a controlled environment .

The majority of the approaches flown in Iraq and Afghanistan are straight-in approaches, so I don't know about minimizing from ground fire. I have ATIS recordings from certain locations that list surface to air small arms and missile fire right after the weather, and that's in the traffic pattern, so you might be a little misguided. Given that the overhead approach is an appropriate civil arrival, it's military use is irrelevant to this discussion. It has nothing to do with recovering aircraft that are low on fuel, and you may be surprised to note that when multiple aircraft arrive on an overhead, they join the downwind, which is often the case. It's a pattern entry, not just a maneuver. Additionally, it's often conducted in other than a controlled environment.

To do this maneuver at a non towered civilian field I would think would come under the careless and reckless reg.

Fortunately, what you think is both wrong and irrelevant, and is not backed up by regulation nor fact.

While the AIM is not regulatory, non compliance with its' recommendations is used to hammer pilots in enforcement actions.

No, it's not. It's not regulatory, and non-compliance is not subject to enforcement, unless that act violates a regulation. Enforcement, you see, is enforcement of the regulation.
 
FAR 91.13 is a regulation, and it obviously can be very subjective. Which is why an administrative law judge will use the AIM to determine if someone's actions are "careless and reckless". IOW, the AIM is a standard by which to judge others actions.
 
FAR 91.13 is a regulation, and it obviously can be very subjective. Which is why an administrative law judge will use the AIM to determine if someone's actions are "careless and reckless". IOW, the AIM is a standard by which to judge others actions.

If I start hearing about FAA sanctions against pilots who follow the direction of turns regulation, but use pattern entries other than the two depicted in the AIM, you can bet that I will sit up and take notice!
 
It's all just a matter of timing. If he would have entered upwind he could have miss judged the speed and climb when turning crosswind. Once he starts the turn he is blind to the departure, so it might even be argued a worse entry than a crosswind.

Why not just cross mid-field????

If you lose sight or get surprised by someone's performance, so what, you never cross flight paths.

Wouldn't common sense dictate avoiding any possibility of convergence vs. arguing personal opinion that a certain pattern entry is always more dangerous than another?

I just don't see the logic.

If you are approaching a rwy from the non pattern side, if you enter upwind adjacent to the numbers of the approach end and in close, you are in a position to observe departing traffic as well as the downwind. if there is departing traffic you can see it and make a judgement about that aircraft's performance and its' relative position to you and not turn crosswind at a point where there would be any chance of that departing aircraft reaching your altitude.
 
If I start hearing about FAA sanctions against pilots who follow the direction of turns regulation, but use pattern entries other than the two depicted in the AIM, you can bet that I will sit up and take notice!

In my opinion, a non towered civilian field is not the place to conduct overhead approaches. I don't view someone entering base, crosswind or straight in, in the same light. The AIM can be dismissed as non regulatory, but in reality it carries a lot of weight.
 
You see a piper single engine prop lined up to depart. Do you know by that information that he can climb over 2500 FPM at 140 KIAS from a 7000 MSL field?

Why cross any aircrafts flight path if you don't have to???

Do you know every aircrafts performance by heart?

Why make a judgement call that could get you killed if you are wrong?

Why lose sight of traffic on the roll by overflying on the upwind?

Never mind. Have a nice day.
 
For insight, here's a schematic that used to be published on sectional charts back in the day when non-radio equipped traffic prevailed. Although not to scale (see the wind 'T') and from a birdseye view, you can get a feel for generally intended flow.

dtuuri

So there is no such thing as a safe right-turnout in that world?
 
For what it's worth, I did a midfield entry to downwind on my private pilot checkride. The DPE didn't say a word, and I passed.

On my instrument checkride, I did a straight in approach. I passed that too, with no criticism from the DPE.
 
For what it's worth, I did a midfield entry to downwind on my private pilot checkride. The DPE didn't say a word, and I passed.

On my instrument checkride, I did a straight in approach. I passed that too, with no criticism from the DPE.

Probably because they're both perfectly acceptable.... ;)
 
Dave Tuuri, thank you for finding Table B and the Morris article. I've been digging away trying to refind that for a couple of months. The eyeball is a lousy detector of constant azimuth/bearing items and when it explodes into attention, you have less than 10 seconds left....
 
Dave Tuuri, thank you for finding Table B and the Morris article. I've been digging away trying to refind that for a couple of months. The eyeball is a lousy detector of constant azimuth/bearing items and when it explodes into attention, you have less than 10 seconds left....


10 seconds is forever in collision avoidance though, these aren't ships.
 
10 seconds is forever in collision avoidance though, these aren't ships.
But here's the rub, View attachment 26801 referring to a 1986 Advisoy Circular:
"The document also says the minimum time for a pilot to see and recognize an aircraft, discern the collision course, decide what to do, and successfully maneuver is 12.5 s."​


dtuuri
 
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I can't speak to the document, but I can tell you from personal experience it's a lot less than that.

I've no doubt that it can take a lot more, with many variables to consider.

If the minimum time to recognize and avoid other traffic were so great, many of us would long be dead, not the least of them, me.
 
I'm familiar with the look-and-live chart, as it's been around a long time. I'm also quite familiar with the AC. I can't speak to the naval publication, but the diagram in the AC regards traffic with minimum closure rates of 300-600 knots. That's not common in the traffic pattern, and one generally has more time; one also has traffic in known places to look (including over the field; one should be looking at upwind, downwind, base, and final, as well as crosswind where it may occur, bearing in mind that traffic may be close to the runway or far from it, or straight-in, depending on type, speed, and nature of the operation. Ag aircraft may be operating well below the pattern, using unusual or unorthodox entries and departures, never reaching pattern altitude during the entire duration of their flight).

The same advisory circular advises against entering the traffic pattern on the base leg, or straight in approaches, though both are very common methods of arriving in the traffic pattern.

If we abolish straight-in approaches, we abolish most of the arrivals from instrument approaches, and relegate ourselves to circling approaches...which can overfly the field and turn in any direction, using any pattern, staying within the confines of obstacle-protected airspace, usually at less than traffic pattern altitude, to arrive at the desired or appropriate runway.

Never the less, insofar as seeing and avoiding, having done so my entire career (as have we all, I would hope), I can assure you that seeing and avoiding traffic at lesser time-ranges than ten to twelve seconds is possible, and necessary in many cases.

It's nice to have full TCAS available, but for many, especially those in light aircraft, it's not possible. Seeing and avoiding isn't just a good idea, but a regulatory necessity, whether IFR or VFR, controlled or uncontrolled.

As such, it's the same responsibility we exercise enroute as in the traffic pattern, and that includes the midfield crosswind entry.
 
...diagram in the AC regards traffic with minimum closure rates of 300-600 knots. That's not common in the traffic pattern, and one generally has more time;
Doesn't matter. The 12.5 seconds is reaction time. Speed only determines the distance the target's away at the last opportunity to avoid, i.e., its size. The study shows the relative size of a 40' target is less than one degree wide at that range and even at slow closure rates and harder to spot head-on than from the side (duh).



...that includes the midfield crosswind entry.
No such thing according to the AIM's description of a standard pattern:
Crosswind leg. A flight path at right angles
to the landing runway off its takeoff end.​
Like I said, you're making up your own pattern.

dtuuri
 
So there is no such thing as a safe right-turnout in that world?
Sorry, I missed your post asking this. Actually, you have that exactly backwards. There's no "right-turnout" in today's world. Back then, and when I used to be an active instructor in my younger days, there was indeed a right turnout and is shown on that diagram. First we made a 90° left turn, then followed that with a 45° right turn to exit from the crosswind leg.

I guess somebody 'smarter' than the rest of us thought that got too close to aircraft entering the downwind at a 45°, so they eliminated the turn to crosswind and the right turn to exit. Instead, now you make a 45° left or just continue straight out, no right turn today.

More recently, they botched the diagram too. It depicts an entry leg opposite the departure end instead of midfield. For those who can't read, entering as shown undoes the spacing margin gained when they eliminated the former departure off the crosswind. A recent fatal mid-air at Corona, CA occurred right there too.

dtuuri
 
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Like I said, you're making up your own pattern.

I'm not making up any pattern at all. There is no required pattern.

Entering a crosswind leg, a downwind leg, a base leg, and then a final is flying the same pattern, an established and accepted pattern, and a proper pattern. That it's entered from the midfield crosswind doesn't make a new pattern.

Likewise, an arrival at pattern altitude over the numbers, where no other traffic is located, where one can view the upwind, downwind, crosswind, base, and final, is nothing more than a left turn to enter the downwind, base, and final, and follows the established traffic pattern, just like anyone else. When other traffic is on the downwind, one can simply turn in ahead of them or behind them, as appropriate, to enter the pattern.

I guess somebody 'smarter' than the rest of us thought that got too close to aircraft entering the downwind at a 45°, so they eliminated the turn to crosswind and the right turn to exit. Instead, now you make a 45° left or just continue straight out, no right turn today.

More recently, they botched the diagram too. It depicts an entry leg opposite the departure end instead of midfield. For those who can't read, entering as shown undoes the spacing margin gained when they eliminated the former departure off the crosswind. A recent fatal mid-air at Corona, CA occurred right there too.

Your god-blessed, sacred pattern changes, and you assert that it's diagrammed incorrectly, yet heaven help anyone who differs from the diagram or your interpretation thereof.

Mid-air collisions have occurred at numerous places around airports, as well as no where near airports. Think about it.

Doesn't matter. The 12.5 seconds is reaction time. Speed only determines the distance the target's away at the last opportunity to avoid, i.e., its size.

It does matter. It's reaction time at that speed at that distance. At slower speeds and the same distances, more time is available to see and avoid, and this typifies operations in the traffic pattern. You'll note that the chart you provided includes both time and distance, and speed. Change any of those, and you change the equation. Increase the closure rates, and there's less time available to see and avoid. The 12.5 seconds isn't simply "reaction" time. It includes time to see and recognize, to react, to make control inputs, and to allow the aircraft to move. Further, aircraft will move much more readily at a slower speed with a shorter turn radius, to avoid a conflict than at higher speeds.
 
You know what I like? Quotes from well respected aviation organizations. Such as this one from the AOPA Air Safety Foundation.

"It helps to keep in mind that traffic procedures at
nontowered airports are advisory in nature, not
regulatory. There frequently is more than one way to fly

a safe pattern, final approach, and landing."

This one's good too.

"Regulations and procedures can’t cover every
conceivable situation, though, and the FAA has wisely
avoided imposing rigid operating regulations at
nontowered airports. What is appropriate at one

airport may not work at the next."

Forget about the downwind we need to be worried about final!

"Most collisions occur on final approach, generally when a faster aircraft overtakes a slower one (see Figure 4)."


Of course this one speaks volumes.


•"
An alternate method is to enter on a midfield
crosswind at pattern altitude, then turn downwind
(see Figure 10). This technique should not be used if
the pattern is busy. Give way to aircraft on the
preferred 45-degree entry and to aircraft already established on downwind."

When it comes to interpreting aviation procedures, I'll think I'll stick with AOPA's award winning ASF over an individual's opinion...but that's just my opinion.

Oh, and just to be clear. Yes, I believe (and AOPA) that descending while on downwind isn't the safest way to enter a pattern. Finally getting back to the original point.

 
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The best way to enter a pattern is to do it on a day that doesn't begin with an "S".
 
But here's the rub, View attachment 26801 referring to a 1986 Advisoy Circular:
"The document also says the minimum time for a pilot to see and recognize an aircraft, discern the collision course, decide what to do, and successfully maneuver is 12.5 s."​
dtuuri


Wow, that is some really poor performance if that is a real number.
 
No problem--follow ASF's recommendation and do the crossover across final.

The ASF recommendation as quoted above was "an alternate method is to enter on a midfield crosswind at pattern altitude, then turn downwind."

You wouldn't be making up traffic patterns, would you? Your version, attributed to ASF, doesn't sound like ASF's version.

Of course, you weren't happy with me entering over the numbers. You'd prefer to do it ASF's way, but you've modified ASF's midfield crosswind to fly over the numbers, instead.

No pleasing you, is there?
 
Wow, that is some really poor performance if that is a real number.
If you take a look at Fig. 4, Part B (the 'table' Dr. Bruce mentioned), you can see the times to impact. I placed marks comparing the way I recommend pattern entry (via a 45° wherever) vs. McFly's and Doug's pattern method. 'My' way, i.e., Part 91.126(b)(1), results in about a 50 mph closure rate for two 100 mph aircraft approaching within 45° of the same heading. At right angles, 90°, the closure rate has about tripled to 140 mph. At 135°, head-on into somebody entering downwind on a 45°, it's 170 mph using Dr. Trippett's Trigamatrick (EDIT: 185 mph using trig). So, the seconds to impact doing it my way is off the chart in the direction of more safety. Their's is well below the minimum required reaction time. Of course, more speed makes it all the worse for them, whereas my way has a margin to yield. I picked an arbitrary 1° angle as the minimum recognizable cross-section:
Fig 4 Part B.JPG

The probability of sighting traffic in time to avoid was also summarized in TABLE II. If these two hypothetical 100 mph aircraft converge at 45° in the same direction, the probablity of them spotting each other is 100%, assuming they spend at least 2/3 of their time looking. But at 90°, the closure rate is 140 mph and the probability drops to only a 60% chance. Even if McFly and Doug are as perfect as they think, it's impossible for them to see and avoid 100% of the time as shown by the 'Optimal Observer' column:
TABLE II.JPG

Of course, for this to be valid, pilots need to be looking in the direction other aircraft may possibly be approaching from. Trouble is, when circling an airport (or flying a rectangular pattern around it), the object of attention when gazing inward toward the airport is downward at the surface for drift and position information as well as situational awareness of departure traffic. After all, it is why we practice ground reference maneuvers. Here's the ASF pattern maneuvers. Cutting across the airport at pattern altitude are aircraft B & C, and descending into it from above is aircraft A. The rest of us are not shown, but are conforming to rectangular patterns symmetrical with the depicted blue traffic pattern courses at varying distances from the runway. Closure rates and cross-sectional areas presented to the eye are easily imagined. Not entering the ASF way ought to be a no-brainer:
Fgs 9 and 10.jpg

dtuuri
 
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Nope, not perfect. Just someone who goes with data and facts to decide a course of action instead of stubborn emotion. Can't speak for "Doug" but having read his comments he's pretty dead on. But then again with a name like Bader you gotta be good.

The whole 12.5 second rule while facinating isn't a hard number. A more updated number would be this-

"The time to perceive and recognize an aircraft, become aware of a collision potential and decide on appropriate action, may vary from as little as 2 seconds to as much as 10 seconds or more depending on the pilot, type of aircraft and geometry of the closing situation. Aircraft reaction time must also be added."

Many variables involved in the equation. I would think an average pilot would take a couple seconds to identify and decide the course of action. After that, reaction time sure isn't going to take 10.5 seconds.

But as you said you must be looking in that piece of sky to be valid anyway. Most midairs (88 percent in 2001) occur with pilots never having seen the other aircraft in the first place so that kinda makes the whole 12.5 secs purely academic. As I stated earlier most midairs also occur on final. Pattern entry is a "negligable" contibutor.

You can come up with reasons (overhead entry) all day long that would seem to be a cause to an midair When the primary one (final) is leg we all must do. A straight in is approved by the AC90-66A. It's a 90 degree angle to someone on base just like a midfield. My chances of having a midair there are far greater than downwind. But I don't go out and stress about "neglibable" outcomes. For instance, I have an aircraft that's aerobatic, should I simply not do aerobatics because it will slightly increase my chances of an accident? That's what risk management is about and the chances of having an accident while adhering to the ASF midfield entry as depicted are not even worth bringing up.

Oh yeah if you're going to try and prove ASF is wrong and you're right have at it but at least don't misquote them. The aircraft in question isn't descending into the downwind.


One method of entry from the “opposite” side of
the pattern is to cross over midfield at least 500 feet
above pattern altitude (normally 1,500 feet agl).
When well clear of the pattern—approximately two
miles—descend to pattern altitude, then turn to enter
at 45 degrees to the downwind leg at midfield.

Finally no one here as ever disputed 91.126. A simple part that basically says airplanes turn left and helicopters avoid airplanes. No where in there does it say you must enter on a 45.

 
Oh yeah if you're going to try and prove ASF is wrong and you're right have at it but at least don't misquote them. The aircraft in question isn't descending into the downwind.


One method of entry from the “opposite” side of
the pattern is to cross over midfield at least 500 feet
above pattern altitude (normally 1,500 feet agl).
When well clear of the pattern—approximately two
miles—descend to pattern altitude, then turn to enter
at 45 degrees to the downwind leg at midfield.

Finally no one here as ever disputed 91.126. A simple part that basically says airplanes turn left and helicopters avoid airplanes. No where in there does it say you must enter on a 45.


Why must you shout? Ask somebody who's been around awhile if they ever had a plane descend in a right turn into the downwind near them. Give a few Flight Reviews at uncontrolled airports too. In practice, it seems literally nobody has the patience to fly for a minute and 20 seconds at, say, 90 kts away from the airport before beginning a descent, and if they do they don't wait another minute (500 fpm rate) before making a level turn back. In fact, just read an aviation forum for how many of them do it and you'll see, in practice, they don't get the job done anyway by their own admission regardless of whether the procedure is a good one or not on the see and avoid issue. That would put them 3.5 nm beyond the airport plus their radius of turn, more for faster aircraft. Not a very good thing to advise for student pilots unless you want to disorient them and get them lost, if not kill them outright during a premature descending turn into the downwind.

dtuuri
 
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