Pelican's Perch #30:
The 45-Degree Zealots

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There's not a syllable in the FARs about 45-degree traffic pattern entries. Nor does the AIM require them. There exists, however, a small-but-vocal cadre of pilots and even some FAA inspectors who consider any other type of pattern entry (straight-in, crosswind, etc.) to be a felony. These

Pelican's PerchFirst, a little housekeeping. For those interested in some of the old books I reprint, there have been several changes. Be sure to check out my list of available publications.

Also, I am often asked "When are you gonna do the the turbo column?" I've now got a turbonormalizer from Tornado Alley Turbo in Ada, Oklahoma, and as soon as I get some time in it, and can gather some of the data I need, I'll be doing the column. Hey, how many columnists do you know that will go out and buy a turbonormalizer, just to please his readers? There will probably be two columns, one on the hardware, and one on how the loose nut between the yoke and the pilot's seat runs it. I'm hoping the very next column will be on the hardware, but that's not a promise!

Once that's done, I'm hoping to publish the engine management columns in a book, for the benefit of the three kind people who have asked for that. Working title is "Modern Engine Management," but I'm open to suggestions!

Those Deadly Traffic Patterns

The most savage controversies are those about matters as to which there is no good evidence either way.

Bertrand Russell

That which is legal is not always safe, and that which is safe is not always legal.

John Deakin

These two quotes are most appropriate when talking about traffic pattern entries.

What IS a "traffic pattern," anyway? The Pilot/Controller Glossary says:

Traffic Pattern - The traffic flow that is prescribed for aircraft landing at, taxiing on, or taking off from an airport. The components of a typical traffic pattern are upwind leg, crosswind leg, downwind leg, base leg, and final approach.

a. Upwind Leg - A flight path parallel to the landing runway in the direction of landing.

b. Crosswind Leg - A flight path at right angles to the landing runway off its upwind end.

c. Downwind Leg - A flight path parallel to the landing runway in the direction opposite to landing. The downwind leg normally extends between the crosswind leg and the base leg.

d. Base Leg - A flight path at right angles to the landing runway off its approach end. The base leg normally extends from the downwind leg to the intersection of the extended runway centerline.

e. Final Approach - A flight path in the direction of landing along the extended runway centerline. The final approach normally extends from the base leg to the runway. An aircraft making a straight-in approach VFR is also considered to be on final approach. (See Straight-In Approach VFR, Taxi Patterns) (Refer to AIM, FAR Part 91) (See [ICAO] Aerodrome Traffic Circuit)

Straight-in Approach - VFR - Entry into the traffic pattern by interception of the extended runway centerline (final approach course) without executing any other portion of the traffic pattern. (See Traffic Pattern)

Straight-in Landing - A landing made on a runway aligned within 30 degrees of the final approach course following completion of an instrument approach. (See Straight-in Approach - IFR)

Pretty simple, but the complexity seems to arise when entering the pattern.

There is a small, noisy group of people out there who seem to think that if only everyone would always make the 45-degree pattern entry to the midfield downwind, there would be world peace, a fish on every plate, and an end to the ozone hole over the South Pole. These same noisy people also seem to think the straight-in approach is the worst sin a pilot can commit, some insisting that it should NEVER be done.

Rubbish to both, I say. I say there is no good evidence either way that any one type of pattern entry is any safer than any other. All have their advantages, and all have their disadvantages, and a large percentage of traffic pattern midair collisions occur at towered airports. If you want an absolutely safe way into the pattern, forget it, you might as well stay home.

First, let's get towered fields out of the way. When operating at a towered field, do whatever they clear you to do, and report where they ask you to report. How you get there is up to you. Remember, the job of the tower is to SEQUENCE you, and NOT to separate you! Whatever aid they give you to maintain separation is above and beyond their charter. (My personal opinion is that we have far too many expensive towers, and far too few uncontrolled fields. If the FAA shut down 50% of the existing control towers, I would applaud. That's my grumble for today!)

Now that we have that covered, the remainder of this column refers to traffic patterns at airport without towers, or "uncontrolled fields," and how to get into and out of them as safely as possible.

Traffic Pattern Nazis

Two incidents stand out in my memory, both at the Arlington, Washington airport. This is a neat general aviation airport north of Seattle, with a primary runway 16/34, an elevation of about 160 feet, a LOC-only approach to 34, and blessedly, no tower. I hope they never put one in, for that would ruin the airport.

For the first incident, I approached from the east in excellent VFR conditions, and was unable to raise anyone on the Unicom/CTAF frequency. I crossed over the airport at about 2,200 feet agl to take a look at the windsock and traffic. It indicated that 34 would be most into the wind, and accordingly, I proceeded to the northwest to join the 45 to the left downwind. I might have joined directly onto the downwind, but I was a bit high and fast, and going out to join the 45 was going to take care of that nicely. There appeared to be no traffic.

In this case, I maintain that if there is any difference in "safety" at all, the direct entry from the crosswind onto the downwind would have been the "safest," as that would have meant less time flying in the airport area, thereby reducing the "total risk." It's possible that proceeding out to the entry area for the 45 would delay the landing enough that all kinds of traffic might be there. But it really doesn't matter much.

Just after crossing overhead, still 2,000 feet or more above the airport, my ears were assaulted by a truly nasty voice on the radio, "Bonanza over Arlington, what kind of traffic pattern do you call that?"

Since there seemed to be no one else around, I said, "If you're yelling at the Bonanza about a mile northwest, northwest bound, I'm not in the pattern yet, I'm headed outbound for the 45, and I'm at 2,000 feet, what's your position?"

"I'm on the ramp, and I've never seen anything like that, you're busting right through the traffic pattern, and that's no 2,000 feet!"

"Well, I'm showing 2,200 feet right now, and if you'd like to discuss it like a human being, I'll be at "The Prop Stop" for lunch after landing."

Of course, he didn't show. Now, what is the matter with this creep? He's on the ground, so he's not affected. There was NO traffic, unless a no-radio aircraft sneaked in while I was away from the airport getting on the 45. Was this a matter of safety? No. Was it regulations? No. It was some narrow-minded jerk with a big mouth, and a small brain. I shudder at the thought he might be an examiner, or an FAA Inspector.

On another occasion, I made the LOC approach to 34, and broke out at about 800' with pretty poor visibility, perhaps a bit over a mile. I had called over the FAF (WATON NDB) about five out, and again when I broke out, stating "Bonanza One Bravo Echo, three out, landing straight in, three four."

It might have been the same traffic pattern nazi who snarled, "One Bravo Echo, you ever think of making a 45?"

"No, not in this weather, what's your position?"

"We're on the crosswind, about to turn downwind, and the traffic pattern entry here is a 45 to the midfield downwind."

"What would you estimate for the ceiling and visibility?"

"It's about 800 overcast, and a mile."

"And you're shooting VFR circuits?"

"That's affirmative."

"Well, when you get on the ground, you might want to take a peek at the FARs on VFR ceiling and visibility requirements. And what was your N-number, please?"

Mercifully, there was only silence in response, and of course, I was at the gas pumps before he could land. I didn't see him on the ground, either.

Let's note the difference between "regulations" (i.e., the FARs) and "policy" (which includes everything else.)

The FARs

The authors of FAR Part 91 have wisely never made a big deal over pattern entries. (That can always change, of course.) The FARs start out with Class G airports (uncontrolled) and work "upwards" to Class B. In general, each "higher" class of airspace adopts all the regulations of those below, and adds to them. I have extracted a few of the regulations below in italics, and added my own comments [within square brackets and in blue, like this].

91.126 Operating on or in the vicinity of an airport in Class G airspace.

(a) General. Unless otherwise authorized or required, each person operating an aircraft on or in the vicinity of an airport in a Class G airspace area must comply with the requirements of this section.

(b) Direction of turns. When approaching to land at an airport without an operating control tower in a Class G airspace area -

(1) Each pilot of an airplane [NOTE: only airplanes!] must make all turns of that airplane to the left unless the airport displays approved light signals or visual markings indicating that turns should be made to the right, in which case the pilot must make all turns to the right; and

(2) Each pilot of a helicopter must avoid the flow of fixed wing aircraft.

It is worth repeating, with emphasis, that making "wrong way" patterns while approaching to land is a violation of the FARs. It is the major hard and fast rule about traffic patterns.

However, note there is nothing whatsoever about departures! You are legal (and generally safe) to turn any way you want, though common sense and courtesy would dictate avoiding normal pattern traffic, residential areas, or hazards to flight in any way you can, and you should consider those factors while giving them whatever priority you judge most appropriate. In the absence of any and these factors, the usual drill is a 45-degree turn in the usual direction, or a straight-out.

91.127 Operating on or in the vicinity of an airport in Class E airspace.

(a) Unless otherwise required by part 93 of this chapter or unless otherwise authorized or required by the ATC facility having jurisdiction over the Class E airspace area, each person operating an aircraft on or in the vicinity of an airport in a Class E airspace area must comply with the requirements of 91.126 [Class G, above].

(b) Departures. Each pilot of an aircraft must comply with any traffic patterns established for that airport in part 93 of this chapter. [Part 93 contains a long laundry list of "special" airports and areas, otherwise it's the same as Class G.]

(c) Communications with control towers. [Deleted here, not germane to this column.]

So much for the FARs on this subject. Note there is NOTHING in the FARs about 45-degree entries, or any other entry. All you have to do is make all turns WHILE APPROACHING in the "established direction." There is also nothing that says you have to make ANY turns, which makes a straight-in approach quite legal.

In fact, I can make a very good case that the classic 45-degree entry is itself a violation of the FARs, since it is ALWAYS in the opposite direction to the established flow of traffic. Since it is the final turn onto the downwind leg, it must certainly be in the "vicinity" of the airport, and therefore covered by the above regs!

The AIM

Paragraph 4-3-3 (d) of the Aeronautical Information Manual (AIM) repeats the FAR about right of way:

When two or more aircraft are approaching an airport for the purpose of landing, the aircraft at the lower altitude has the right of way, but it shall not take advantage of this rule to cut in front of another which is on final approach to land, or to overtake that aircraft (14 CFR Section 91.113(f)).

Think about this. If you are on downwind, and you see an aircraft on final that is below you, THAT AIRCRAFT HAS THE RIGHT OF WAY. To carry it even further, even if the aircraft on final is HIGHER than you are, it STILL has the right of way, since you may not cut in front of an aircraft on final!

This is hardly the language that would be used if straight-ins were frowned upon.

Common Sense

Bureaucrats, like those who write the FARs, just hate that term "common sense" because it generally cannot be quantified, reduced to numbers, or stated clearly in modern FAA-speak. I submit to you that traffic pattern "rules" can be reduced to simple common courtesy, and common sense, and we can safely forget all those complicated diagrams. (To tell the truth, almost all rules everywhere could be thrown out, if we'd all just show a little common sense and common courtesy!)

All a pilots needs to do is give a little thought to the type of traffic known to exist (if any), and the type of traffic he is himself. Above all, the single most important question we should ask ourselves is this:

"How can I do what I want to do (get from here to the gas pump), with the absolute minimum impact on what others are trying to do?"

I like to drive my car so that no other driver has to put on his brakes, or turn his wheel because of something I do, and I try to fly the same way.

Do I use the 45-degree entry? Of course! It's very useful when there is a busy pattern, and I can fit into that pattern with my speed and characteristics. When it gets very busy, or dissimilar aircraft are involved, even the 45-degree entry breaks down, and that's why you see the pattern in use at Oshkosh, during the big show there. They set up a point (RIPON) a LONG way away from the airport, and they ask everyone to first fly over that point, and then follow VFR landmarks directly to the downwind. That gives everyone a lot of time and distance to get sorted out, just as the usual 45 does at a normal airport.

At the other end of the scale, if I owned my own private strip that no one else ever used, I'd make pattern entries any old way I wanted, all the time.

Between these two extremes, there are infinite variations, each with a "best" way to enter. Sometimes that "best" way is the 45-degree entry, and sometimes it is not.

Some Examples

Let us suppose you're at the end of a long cross-country flight, and in order to get down to the pattern altitude at your home airport (no tower), you shoot some sort of instrument approach, breaking out below a well-defined ceiling at 1,000 feet AGL, with excellent visibility. Because you were very busy with ATC, you were unable to listen to the CTAF frequency, so you have no idea how busy the traffic pattern might be until you cancel IFR for a VFR landing. Knowing the traffic pattern altitude (TPA) is 800 feet AGL, you carefully fly all the way around the airport well outside the "vicinity" of the airport, enter the 45 at 800 feet, fly to the midfield downwind, fall into a gap between two other VFR aircraft, and land. That "traffic pattern nazi" would be pleased with you, right?

Sorry, pal, you have just seriously violated an important FAR. When VFR, you are REQUIRED to maintain 500 feet below any cloud, and you should have flown the 45 and the pattern at 500 feet AGL. Remember, the TPA is NOT regulatory, it is just a guide to "normal operation." In much the same way, the type of entry is also just a guide to "normal operation," which may be modified by other factors.

Let us suppose you are approaching a strip in the bottom of a valley, with mountains so close on each side that you cannot do anything but a straight-in approach? Obviously, it would be foolhardy to attempt anything else, and this, along with many other variations is good reason the FARs do not address this issue in more detail, leaving it to pilot judgment.

Let us suppose you are approaching some nice uncontrolled airport in your Cessna 182, and I am approaching in the Constellation, with its 140-knot pattern speed? Seriously now, do you really WANT me to enter on the 45, mixing it up with other aircraft trying to do so? Do you want me to leave the wake vortices out there for other smaller aircraft to blunder into? Do you want me flailing around out there with a large, not-very-maneuverable aircraft at much higher speeds, and much poorer visibility? Yes, I can and should do that at 1,500 feet, but how are we to get to the runway? I will be faster than you, approaching from above and behind you, and descending at some point, with you in my blind spot, and I in yours. Don't you think it just might be better for all concerned if I just made the straight-in approach, and got the heck out of the air, out of the traffic pattern, and out of your hair? Even if I have to fly further to get to the straight in, than I would the 45?

Speaking of the Connie, when we were doing closed traffic with it at Camarillo, we should have been at 1,500 feet on downwind, right? Well, that would have put us squarely on the ILS and Glide Slope for Oxnard, five miles away, flying directly into descending traffic. I felt it was more prudent to just use the normal TPA, and fly a wide pattern, and I would have done the same even if Camarillo didn't have a tower.

Suppose you approach some airport so that you cross overhead the airport, aimed at the same point where the normal 45-degree entry would turn onto the downwind. As you pass over the runway, you note there is no traffic in sight, so you turn directly onto the downwind. Some will say you shouldn't do that, but now assume that instead, you had flown around the airport vicinity, and entered the 45 like a good little doobie. As you approach the turn to the downwind, you look back along the downwind, and note there is no traffic, so you continue.

How is the one "safer" than the other? For either, the chance of missing traffic is equal. In fact, in Canada, the crosswind entry is the preferred method, and I'm not even sure the 45 entry is even mentioned!

Look Everywhere (Including Straight Up)

I know of one FAA inspector, a good man, very helpful, highly respected, puts out a dynamite newsletter, very active in the local aviation community. But he is absolutely monomaniacal about the 45-degree entry, and becomes quite belligerent when talking about it. The last four times I've heard him address a crowd, 90% of his attention is on this item, and the clear implication is that the 45 is absolutely the only way to go. One group of examiners came away with the clear impression that he absolutely wants any applicant busted for not doing the 45. The entire group was literally cowed by his extraordinarily strong attitude on this. I hate to think of what the results will be.

Wrong message. BAD message, I say.

He bemoans the current "lack of discipline" in this matter with "Where I used to know where to look for potentially conflicting traffic I now have no idea where they might be coming from. I literally have to look everywhere, including straight up!"

Poor baby. Have I got news for him? It has NEVER been safe NOT to look "everywhere, including straight up!" In fact, I would suggest that if we did away with ALL "policies" for traffic patterns, and teach that people MUST look everywhere, that anyone may come in from ANY direction or altitude, we just might raise a crop of far more vigilant pilots than we have today. THAT is the real problem here, I think.

Courtesy and Kindness

Let us suppose you are on downwind, abeam the numbers, and someone calls on a final approach, straight in. You spot him, and there appears a conflict which requires you to extend your downwind to fall in behind him. Are you upset? Some will be, but suppose he's a bit marginal on fuel, or needs a bathroom really, really badly? Would you really have him stop somewhere else first, or go all the way around for the 45? Suppose you've been shooting circuits and touch and go landings for an hour, do you really feel you own the airport? Suppose half a dozen of you are doing circuits, and have the spacing worked out so that everyone is just "fitting in," no "slots" left, and I come along in my Bonanza? Do you feel that I should just go away because you guys were there first, and that there's no room for me? What's the difference to you if I make the straight in, forcing you to extend slightly, or if I make the 45, break in, and force you (or someone else to circle, or even leave the pattern? (All assuming decent communication and courtesy, of course.)

Of course, there's always the arrogant you-know-what who will make any pattern he pleases, regardless of courtesy, common sense, or traffic, but he won't read this column anyway, and it's not that type I'm addressing here.

I think it's best to look at each situation with a neutral eye, and figure out what's best to make the whole system work the best. In Interstate traffic, that might be slowing your car a bit to let merging traffic join, and in the airport traffic pattern it might mean giving way to the Learjet making a straight in. Then again, it could also mean going a bit out of your way to make that 45-degree entry, and take your place in line.

When someone else does something you think a bit out of line, you'd also do well to just figure he had a pressing need to do that, and someday you may need to do the same. There's no sense yelling at someone unless they do something downright dangerous, deliberately and knowingly. Even if someone does do something you perceive as dangerous, you'll accomplish a lot more with a gentle approach, something like "I was concerned about what you did, would you mind sharing your thoughts on it with me?"

The rude, obnoxious you-know-what will tell you where to go, and you've lost nothing. You MIGHT make him think about it later, and he MIGHT realize his error on his own. Or he'll brag to a buddy how he told you off, and his buddy might just say, "You know, I think you might think about that, the guy might have a point."

With others, you will probably make a new friend, and you both might learn something.

An example of this sort of thing, and the way I try to look at it. At Camarillo, we often do repetitive full-stop landings and taxi-back in the Curtiss-Wright C-46, since it is a tail-dragger, and most of the skill to be developed is ground handling on the runway during takeoffs and landings. Touch and gos don't accomplish much in this airplane! When we taxi back for takeoff, we approach the runway on a fairly narrow taxiway ("A"), with the runup pad to our right. It's a fairly small runup pad, and our wingtip overlaps it slightly. There are often small aircraft lined up there doing a runup and the tower often clears us onto the runway "If able to pass the runup aircraft." The C-46 wingtip is some 14 feet off the ground, so there's plenty of clearance, even with larger twins parked there. We approach each fairly slowly, and wait to catch the pilot's eye before moving in front of him, and we've never had a problem. Most look carefully (some in awe), then smile and hold a thumb up, showing "Plenty of clearance." Some will even yield the right-of-way, saying "We'd like to watch that thing takeoff."

But the other day, a Bonanza was running up, and he had parked just a few feet further forward than usual. I judged we could still pass safely, and even ran my left wheel off in the dirt, both to give more lateral room, and to drop the left wheel off the taxiway, and raise the right wingtip over his prop. From the C-46 cockpit, we can also look out and right down the lower wing surface, so we have an excellent view of the clearance on such things.

But the Bonanza pilot was obviously startled, and quickly shut down, thinking it was too close. We got it sorted out, but he was obviously unhappy, and later dropped by the CAF hangar, asking for me to come to his hangar for a chat after I got back. I did, and the first words out of my mouth were "Hey, if I scared you, or caused you concern, I sincerely apologize." That cooled things off, and eventually I laid a tape measure along his prop, showing that we had about three feet of clearance. We agreed that maybe I had pushed it a little too much, and that maybe he hadn't had a good angle to judge it, but I agreed he had done precisely the right thing in shutting down. I didn't mention his parking too far forward, but he did! We then chatted briefly about other things as fellow Bonanza owners, and he indicated interest in my new turbo. He will probably be a bit more careful not to intrude on the taxiway during runup, and I'll probably be a bit more careful about overlapping running props.

A little courtesy and kindness just works better than any rule or policy.

Be careful up there!