Arriving at the VFR sweet spot – without colliding or spinning in

To me, the sweet spot on a VFR approach is when 500 feet above the ground and descending toward the runway. Here, if the sight picture of the runway is correct and the configuration, speed and rate of descent are right on, the fun part, the landing, should be a piece of cake. The question is, how do you get to that sweet spot with the least possible risk?

To do it right you need to start early and plan the whole arrival process carefully. I don’t think there is enough training emphasis on arrivals and my feeling about this was reinforced when I had good sessions with Concorde training in the 1980s.

The Concorde flew all its life with few additions to the original avionics. There was no electronic vertical navigation feature and no big nav screens. The instruments remained mechanical.

Concorde cockpit
In Concorde, you’d better work the computer between your ears for vertical planning.

I have told this story before but it relates to the subject I am about to explore. Picture yourself cruising along in excess of 1,100 knots, up near 60,000 feet, with the challenge of making all that energy come out even with a gentle stop at the JFK gate. One Concorde captain told me that all you have to do is use the computer up here as he tapped his head.

The importance they placed on a good arrival was shown in a simulator session that covered a Heathrow-JFK hop. Once at cruise the sim was moved across the Atlantic at super-supersonic speed but it was not moved to the point where the approach to the runway started, it was moved to what they called the deceleration point. That was where the slowing down and starting down process got under way.

This is just as important on the airplanes most of us fly as it was in Concorde. If the letdown and arrival is botched, nothing that follows will likely work well.

I used to ask arriving pilots how many flying miles they thought we had to go until touchdown. Many would look at me like I was crazy because there was nothing like that on the FAA written or in the training materials.

If they didn’t have a clue about miles, I might then ask how many minutes to fly until touchdown. The purpose of either question is to define the amount of time available to do all the things that are required before reaching the sweet spot, followed by the tires going chirp chirp. What I learned is that most pilots just don’t think about either miles or minutes to touchdown when arriving.

For now let’s think of a VFR arrival at an uncontrolled airport.

If there are no terrain or obstructions that dictate otherwise, the plan should be to arrive at the traffic pattern altitude a few, say three, miles from the airport. I would plan to do that based on starting my descent five miles away from that point for each 1,000 feet high. That is a descent rate of 500 feet per minute at 150 knots groundspeed, add or subtract 100 fpm for each 30 knots above or below 150.

That is a leisurely descent rate but I always felt it to be the most efficient and comfortable way to let down.

A little AIR FACTS history for your amusement: The call on the Common Traffic Advisory frequency when five or ten miles out actually stems from a proposal my father, Leighton Collins, made in the September, 1967 issue of AIR FACTS. He called it a Traffic Pattern frequency but most of what the FAA developed as the CTAF followed his idea.

There is one questionable procedure in the AIM recommended CTAF procedures. Why identify by N-number? That means nothing to the other traffic which might be able to see you as a Cessna 210, for example, or a green and white Cessna 210 if close enough. The main thing is to state your position and intentions. Cutting down on words is especially important at busier uncontrolled airports where the CTAF can get pretty congested.

Best have a plan for the traffic pattern when three miles out, too. By regulation, there is only one traffic pattern requirement and that is for all turns to be to the left unless otherwise dictated by Notams or, I presume, word from a Unicom operator. If the active runway can’t be determined by other means, the old practice of circling the field and looking at the wind sock is still there to use.

Standard airport traffic pattern
Do you always have to fly that 45 degree entry?

There are traffic pattern recommendations and over the years these have been studied and hashed over many times. Often the product of these studies seems to have come from good folks who could make scratching your head complicated and expensive.

The recommended attitude of 1,000 feet above ground level has been around for a while but it was once 600 feet. It is hard to argue with the suggestion to enter the downwind at a 45 degree angle but, for me at least, it is also hard to argue with a left base entry or a straight-in approach if either fits the direction from which you are approaching.

It takes a good awareness of what is going on to avoid two well-proven hazards when maneuvering for landing at an uncontrolled airport. This is prime territory for collisions and low-speed losses of control.

It has long been true that most midair collisions happen in the vicinity of uncontrolled airports. Proper use of the CTAF helps here and a traffic advisory system in the airplane is also an excellent aid. Defensive flying can be added to the mix but when all is said and done the only way to avoid a collision is by visually acquiring any threat and then avoiding it.

Seeing other traffic works better if the traffic is above you, with the sky as a background. Airplanes below can blend in with the terrain or other features on the ground. This suggests that any pattern be flown a bit on the low side. Maybe that is a good idea but if everybody did it then it wouldn’t work for anybody.

Perhaps the best defense is to consider the announced traffic, from the CTAF, along with traffic shown on your screen and work hard at spotting those airplanes. Then you can fit your airplane into the traffic regardless of where you are joining the flow to the touchdown zone of the runway.

One other thing to consider is that in most midairs that occur in the landing pattern one or both airplanes is descending. Look where you are going. A midair spoiled my whole day many years ago and the other airplane was there for the looking by either pilot but neither looked in the right place. There is no way to know exactly where other airplanes are or what they will be doing but you do know where your airplane is and where you want to go. Just be sure the way ahead is clear of other traffic.

The other proven pattern hazard is the stall/spin event that comes when steep low-altitude turns are attempted while trying to salvage a screwed-up approach and get lined up with the runway.

Something to consider here is that all those wonderful stalls and recoveries you practiced at altitude will not do you one bit of good if you fail to manage angle of attack down low and let the airplane depart from controlled flight. There simply won’t be enough altitude for a recovery.

I have always thought that we should teach pilots how to fly without stalling instead of doing all that relatively worthless stall practice at altitude. We do need to add spin demonstrations to the mix, too. If a pilot has seen a few spins, he will know what happens if he gets too low and too slow and the only spin he ever sees is the last one. It is just not possible for a pilot to appreciate the hazards of a low-speed loss of control if he has not seen a few spins. To me a few spins are worth more than a thousand stalls at altitude.

Citation on final
This is the point where everything should be just right.

One pattern item of prime consideration is the wind. In a crosswind situation there will be either a tailwind or headwind on base leg. A headwind doesn’t cause problems but a tailwind can push a pilot into an overshoot of the final approach course. If that happens, best fly the pattern again with the downwind leg farther away from the runway.

There’s a good rule of thumb to follow here, too. If maneuvering for any purpose at a relatively low altitude, best put an absolute limit of 30 degrees on the acceptable angle of bank. The increase in stalling speed goes out of sight when the bank steepens past 30-degrees.

My traffic pattern flying underwent a substantial change after we ran Landing as a Science in the February, 1966 issue of AIR FACTS. The author, Captain Gordon L. Graham, USMC, was an instructor-pilot at Pensacola where the most demanding arrivals and landings of all are taught with a great deal of care and precision.

The last of the traffic pattern is taught as a continuous turn from downwind to final commencing when abeam the approach end of the runway. That is based on the runway being a carrier which is moving forward enough for this to result in a bit of a final approach. If landing on a fixed runway, they taught to make the first part of the turn at a shallower bank angle to make room for a bit of a final.

My concern about this procedure was based on being able to judge a proper approach path while turning. Gordon, whose father Art was tower chief at LGA and an old friend of my father’s, tried to explain this in the article as well as to me on the phone. That wasn’t working so he arranged a rendezvous and took me flying in a Navy T-28C for a little show and tell.

I got it, and from then on when I did a downwind pattern entry I’d make that close-in continuous turn to final starting just after I was abeam the approach end of the runway. I could tell, from halfway through the turn, whether or not the end of the runway was coming at me properly just as well as I could tell on a straight-in approach and any adjustment was easy to make. I think the circle to final made it easier to anticipate any developing problem as long as I was thinking well ahead of the airplane, something I always tried hard to do. If your thinking gets behind the airplane then a successful conclusion depends more on luck than anything else.

In a low-wing airplane the circle to final would block the view of any airplane that might be on a long final so it was proper to take a look when about half way around in the turn. In a high-wing, the view of anyone on a long final was unobstructed.

It might be suggested that this reduces the risk of a mid-air collision by limiting the time in the pattern but that’s a stretch. To me, the main advantage was in ease and efficiency. I always flew the downwind at a distance that allowed that final turn to be at about 20-degrees of bank so there was no steep turn at low altitude.

I know that some folks want to teach long and stabilized straight-in approaches and they are perfectly free to do so. But the continuous turn to final was always pretty fun to me and after I had done it for a while I couldn’t imagine doing it any other way.

As related by Gordon Graham, the Navy taught that the airplane should be in the landing configuration at the 180 point and that the approach should be stabilized throughout the turn. That seemed a bit much to me and I usually didn’t select landing flaps until I was at the 90 position. That would just be a matter of choice.

Gordon also said that it is easier to teach approaches and landings to people with an athletic background. I can hit the sink with the washcloth from the shower every time. Does that count?

UND AOPA study
The circular pattern “gets you to happy hour a few seconds quicker.”

For John’s take on current research on patterns flown like this, see his December 1, 2016 blog Searching For A Miracle Cure To Loss Of Control Accidents. John accurately points out some potential flaws in the continuous turn from downwind to final but I think both he and the entities researching the possible adoption of this miss one big point. There is no requirement to fly a traffic pattern so anything anybody comes up with is meaningless. At the most it could become a recommendation. My point is simply that the continuous turn from downwind to final is easier and it gets you to happy hour a few seconds quicker if things like that count. I also do think it might help pilots stay away from those deadly steep turns at low altitude.

There’s one other variation to consider and that is the sweet spot in a power-off approach. These used to be the norm in light airplanes and a power approach was rather derisively referred to as dragging it in. Now, though, the power approach is more the norm and I have to agree that they are somewhat easier and more suitable in heavier light airplanes.

Just as twin pilots practice engine-out approaches, though, pilots of singles, even relatively heavy singles, need to practice power-off approaches. In many airplanes, a real energy-management challenge can be found there.

I think my P210 might have been the poster child for power-off approaches that almost resemble autorotations in helicopter.

If the throttle was cut abeam the end of the runway and a turn to final started at that point, the recommended 1,000 foot pattern altitude wasn’t enough. It took an extra couple of hundred feet to be able to reach the runway with the power off.

I would put out approach flaps to begin, saving full flaps until a landing at the desired spot was assured. For speed, I used a bit more than 78 knots, 1.3 Vso, because it takes quite a bit of energy for a regular flare and transition to a landing attitude. I found 85 to be adequate.

At 500 feet I wanted to have the sight picture of the descent exactly right, or very slightly on the high side. When powerless, there are things you can do to descend faster but not much you can do to descend more slowly. It’s important to know the effect of flaps setting on stalling seed, too, because if the last part of flaps extension doesn’t lower the stalling speed much that’s because it is mostly drag and that could be used to modify the approach path. The flat plate drag of a windmilling constant speed prop might also be reduced by pulling the prop control all the way out and getting it out of flat pitch. You need to know whether or not the prop on the airplane you are flying is controllable in a power-off glide.

Power-off spot landing used to be a staple in training and when check flights were first given to aspiring pilots the inspector would often stay on the ground and observe a couple of spot landings and a two turn spin (at altitude) and issue a certificate based on those two items. For my nickel, spot landings should still be on all check rides in single-engine airplanes.

Why do I think all this is important in relation to the current evangelical zeal about a problem (loss of control) that was one of the things that prompted my father to start AIR FACTS in 1938? Then and now, when the fatal accidents are examined it is apparent that pilots lose control because they fly themselves into sinister places and either don’t recognize what they have done or recognize it too late.

Designating a sweet spot on the approach that is flown to with great planning and care and beyond which the approach is not continued unless everything is just right simply addresses a whole bunch of problems including losses of control on go-arounds which seem to becoming more common. There’s also the reward of a perfect landing which is far more likely after a perfect arrival.

23 Comments

  • I’m glad to hear you are a fan of the “Navy” approach. I too learned to land this way and find it much more easy, convenient, and stable than the square approach. I’m not sure about improving loss of control accidents as one can still overshoot depending on how well the wind is judged. But It also makes every landing an “engine out” practice landing so if that day ever comes it will just come naturally.

    As for preventing midair incidents, if I had it my way all airplanes would be required to have radios. Since that probably won’t happen I think those that do should at least improve their radio etiquette and make better position calls when other aircraft are in the area.

  • One presumption too many:

    “By regulation, there is only one traffic pattern requirement and that is for all turns to be to the left unless otherwise dictated by Notams or, I presume, word from a Unicom operator. ” FAA prohibits using Unicom to control air traffic! While Unicom may “mention” that runway 15 is in use (a useful fact), the guy on the ground can’t clear or direct aircraft movements.

    If the arriving traffic lands on runway 33, lawyers for the people landing on 15 might be camping on the lawn of the “helpful” guy after the collision.

  • Wow, “circular pattern”! 2nd Traffic and GUMPS optional, yes to a spinning head, no to a stabilized approach. Legal yes, smart no! sound like a the FAA needs to write another rule.

  • When I practiced engine out approaches (C172 and C150) my instructor had me delay putting in more than 10º of flaps until I had the runway ‘made’. I could either go full flaps on final or slip it to lose altitude.
    I found that a C-150 is way easier to slow down and way harder to accelerate than a C-172. The latter will glide farther. I did these engine outs onto a runway of 2700 ft length and 600 ft agl pattern altitude.
    On an airport with a longer runway (4500 ft length, 1000 ft pattern agl) the instructions were similar: go for the runway numbers and be sure you have it made. I flew a slightly larger pattern but still far from standard.
    I like the circular approach; I can see what’s going on around the airport better that way with the shallower bank angles.
    I had to slip in a C-172 with 20º of flaps (engine was ok) at CCR; the X-wind was excessive; I used some top rudder to help get it down from a straight-in approach.
    I have been a licensed pilot only 10 months; any helpful comments are appreciated.
    Thanks for the great article.
    ‘A good landing occurs when you can fly the aircraft again’.

  • Richard…I recall the flight that you and I took over to Catalina Island in the Cheyenne XL…with that optical illusion on final, your “sweet spot” was kind of important…

  • Mr. Collins.. This is the second excellent article in which you reference “Landing as a Science” in the February, 1966 issue of AIR FACTS. But the original article is nowhere to be found. Please do a post of that article in full. Thanks
    RMM

  • Great follow-up to the flight instruction you explain on approaches vfr and ifr, in your videos, “Staying Ahead of the Airplane” and “Practical Airmanship”. You have transformed “aviation” and flying to a real-time experience, something to be fully
    engaged in at all moments of the flight. From weather planning to the landing, your expertise is refreshing and “practical”. Never heard of the circular pattern approach.
    Seems better than trying to square the box up and smoother. Thanks for another great learning experience. Gary

  • I am always shy about getting down to pattern altitude until I am in the pattern. My thought is that most mid airs have one plane descending and if that is me I can make sure the way in front of me is clear. I stay at 500 feet above until I am 1 minute (about 1/2 mile) from the pattern and then join. Richard suggests three miles But doesn’t say why. I am confused because I have only found one other thing that I would even quibble with he has written here. Help?

    • That’s an arbitrary number. Some say five miles. It is thought best to be flying level before joining with other traffic.

    • Mark,

      Retaining altitude, even excessive altitude, when approaching the airport pattern is always a good thing, because in the event of a problem with power, you’ll never be glad to have had less altitude than you needed to reach the runway. Most light aircraft can lose altitude easily and very quickly with a reduction in power combined with a slip and/or flaps.

      Note that history shows that most losses of engine power are immediately preceded by a significant change in throttle position … so cutting power down to slow down is when you are at higher risk of a power failure. This seems to be a particular issue with carbureted engines, when the pilot fails to apply carb heat during a power reduction.

      • Differences of opinion are fine but misinformation is not. The myth connecting power changes to power failures was debunked many years ago. Some research suggested that it might have been true with old radial engines but there was even some doubt there. As for carb ice, some manufacturers suggest full carb heat when reducing power where others do not so there is nothing concrete there.

        • It is no myth that power reductions on carbureted engines without applying carb heat causes carb icing depending upon the atmospheric temperature and relative humidity. If carb icing occurs, it will cause at least a partial power failure, if not a full power failure. It’s physics and thermodynamics, not a matter of opinion. I’m surprised you would argue that point.

    • Thank you both!!

      FYI the only other thing I have even quibbled with is a comment made in The Perfect Flight about pre flight being more thorough when launching into IFR. I always do the exact same pre flight every single time, even checking fuel quality when no fuel has been added and the plane has been hangared between flights. I am sure that is the difference between 1,000 hours that I have and many thousands others have. But I hope to resist changes because when I am throttling up I don’t like to think about ‘DID I DO EVERYTHING?’

      Re circular approach vs rectangular discussion I have always used the circular when circle to land IFR or even MVFR because I like to hug the downwind in those cases and rectangular pattern when VFR.

      It was a gut kind of a thing after reading it in The Next Hour where it was first discussed as an anecdote about how the military fly patterns and not an item discussed then or here as an IFR technique. One of my instructors didn’t like it so I did it his way when flying with him. My more senior instructor was agnostic at the time but later told me he now sometimes does the circular when IFR.

      IFR I maintain altitude at the highest level I can see with a relatively lot of power in (18″ MP) and then drop the nose and the power to 13″ when the runway comes into view out of the left lower corner of the windscreen during the turn.

      VFR I just don’t feel comfortable with it because some of my fellow Chicago pilots are so picky about how everyone else should fly the pattern and others could end up doing a right base in a left pattern so VIGILENCE, TIME to SEE and ROOM are the reasons why. The flat base leg gives me time to regroup and scan without worrying about looking around a wing to line up or focus on maintaining a safe angle of attack.

      I do try to do straight ins VFR if no one is around and it makes sense and have always liked to hear others think that is just fine.

  • I feel that we are making the approach way too complicated.

    First, I’d argue against ANY flaps for a light GA aircraft until the runway is made… even if 200 ft, out of and approach. Approach flaps are just NOT needed…. way overkill and just more work for anything smaller than and including a Baron, Navajo, or 310. Even some turboprops really don’t need them.

    Also, I could argue to keep a fairly constant airspeed until your ready for flaps on short final. (keeps the trim and the rate of descent constant).

    And, the Concord and military jets have little commonality with a GA plane other than planning ahead.

    As for the constant turn base to final…. not needed and a dangerous move if you don’t take the time to see if someone is on final. I’m against it.

    As for limiting bank, I could argue to limit it to at least 45d, but LEARN HOW TO DO IT…. it works fine, but in a steep bank one needs to unload the plane and not pull back. If done properly, the pax will not notice a thing.

    The sweet spot should be continuously throughout the approach from the time you put the gear down and start down.

  • The circular approach isn’t “easier” – it’s just different. Getting on the ground a few seconds earlier is only important if you’ve got a full-bladder emergency in the cockpit, otherwise, why cut short your flying? I enjoy every second of flying.

    The circular approach WILL result in more mid-air collisions at uncontrolled airports. Even in a high wing aircraft such as the ubiquitous Cessna singles, at a 30 degree bank you cannot see another aircraft at or below your altitude to your right on short final at a normal 3 to 4 degree approach slope, just due to the banked flight deck and the view obstruction out the window opposite the left seat. Whereas in a wings-level base leg, you can more easily see any aircraft on short final to your right, regardless of their altitude.

    In any aircraft, there is great benefit to leveling the wings on a base leg, and spending at least a few seconds scanning the general area around the approach end of the runway and to your right, before committing to turning to final.

    Also, if there is a tailwind on base, it will still affect your continuous turn and lengthen your turn arc … consequently, the continuous turn does nothing to eliminate the temptation to use excessive rudder that turns into a stall and spin to the ground … indeed, it actually increases the temptation to do so because your so-called “stabilized” continuous turn has no allowance to make up for mis-judging your downwind leg offset from the runway … whereas a base leg can easily be shortened and if necessary, eliminated entirely if the pilot mis-judged the crosswind.

    Finally, while the FAA does not require any particular pattern design or pattern entry as long as you observe the left hand rule as well as the designated pattern per NOTAM, the more predictable the entries and patterns that pilots use, the less likely a mid-air collision.

  • FWIW, I’ve always used this formula as a general guide to arrive at pattern altitude in a 172.

    My altitude minus pattern altitude times .004. Example 4500-1500=3000. 3000x.004=12. So 12 miles out begin descent from 4500 for a TPA of 1500. Start at 15 miles out to arrive at TPA three miles from the airport.

    • So, let’s see here, roughly speaking of course, …..Concorde at 1100 mph; 60000 ft – 1000′ JFK pattern x .004 = 236 miles out. But going 10 times faster than your Cessna does that mean 2360 miles out to start down??? Ok maybe only 2000 miles. Yikes!

  • I had a few hours of dual with Damian DelGaizo in his Stearman for the primary purpose of breaking my habit of peering over the nose in a Taildragger but a fringe benefit was he had me shoot 180 degree carrier approaches.

  • Duane seems to be particularly strong minded about some things. I enjoy good debate in a way to allow me to think about it all and make my own (hopefully right) decision. Not to beat the dead horse much more, but as a point of reference to the above discussion, I used to fly an Archer quite a lot. The POH simply says under the heading of ‘Descent’ – Carb Heat “if required”. No other mention of carb heat. We would often do a check to see how things felt. Not one time in several hundred hours did we ever get any indication of carb ice. Never used it in the pattern or on final. Carb’d Cessnas POHs OTOH typically all say DO use it, particularly when the throttle is closed. I believe in physics and thermodynamics and all that stuff but apparently design plays into it too! I could, but won’t, argue, I mean debate, some of his other points…..

    • Carb icing is well proven as well as scientifically founded, but just like airframe icing, the actual occurrence depends upon variables that occur intermittently, depending upon external factors like atmospheric temperature, humidity and the operation of individual engines.]

      But, the problem is, like so many other risk factors in flying aircraft, you can ignore the risk of carb icing for hundreds or perhaps even thousands of flying hours and it won’t bite you … until suddenly, one flight, one day, it does. That one flight where the conditions are just right to induce carb icing. I’ve experienced carb icing several times in many years of flying (not in a landing approach, just cruising flight), but quickly responded with carb heat and it was no issue, because I was at altitude.

      However, if you ice up your carb in the landing pattern, at low altitude, perhaps not enough altitude to recover, then it can ruin your day.

      It costs nothing to apply carb heat, except perhaps a tiny reduction in max power that is instantly recoverable as soon as you turn off the carb heat.

      Over the years there have been quite a few loss of power accidents in carbureted piston-engined aircraft that were “unexplained” by obvious visible mechanical failures or fuel starvation. The thing is, if your engine stops running due to carb icing, by the time a mechanic or an accident investigator gets around to examining the engine, the ice is long gone.

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