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Clearance Over Compliance

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Careful readers will note a connection between my blog on our experience with the Denton, Texas tower last Friday and the horrible Cirrus fatal accident at Melbourne, Florida last Wednesday. The connection is not necessarily obvious, but both of these incidents may be cut from the same cloth, specifically ATC clearances or instructions that either exceed the pilot's comfort level, are improper on their face or are just confusing.

I say "may be" because there is no established cause and effect for the Melbourne crash. For all we know, the accident would have occurred no matter what the control tower did or said. But the fact that the controller said on the frequency "cut it in tight" is a legitimate point of departure to discuss, shall we say, ATC instructions that encourage a pilot to get a little more jiggy with the airplane than he otherwise might.

Fortunately, there aren't many of these, but in poring over the NTSB's accident files, I see them from time to time. Almost all of them are, ultimately, the fault of the pilot. An acquaintance was killed at Oshkosh in 2001, the result of a textbook stall/spin caused by trying to over comply with a controller request to slow down and S-turn to build some space into the final sequence.

Yes, over comply. Now this sort of thing would never happen to me because I am an exceptional pilot. Always have been. And if ATC's plan requires a higher performance maneuver of some kind, well, I'm here to tell you my superior skills are more than up to the task. In fact, I am eager to demonstrate them with just the slightest encouragement. You want a tight turn in? I'll show you a tight turn in, brother. You get the idea. There is a vaporous membrane between, "wow, that guy is really a good stick" and "cripes, that guy just went in." Most of us, myself included, are probably ready to dance right up to that line and cross it without realizing it as a demonstration of our raw skill as pilots.

Despite how far we think we've come with training and awareness of what it means to be PIC, it sometimes doesn't take much to relinquish just enough of that to ATC to fly right out of the envelope. Remember the Jack Roush Beech Premier crash at Oshkosh in 2010? The NTSB hasn't gotten around to a final cause on that yet, but after the fact, Roush was quoted as saying the tower's instruction or landing clearance put him outside his comfort zone and in conflict with traffic on the runway. An attempt at a go-around was obviously unsuccessful. And if any place will do that, it's Oshkosh during AirVenture, when thousands of rusty pilots sign up for a virtual convention of over compliance.

Our little incident last Friday was, in the scheme of things, a gnat on an elephant's butt. Rather than declare "unable," we just angled away from the high obstacles we had been invited to ignore. Not that I think controllers should be enjoined from using phrases like "bring it in tight" or telling a pilot to taxi and depart without delay because traffic is on short final. I can't count the number of times when that kind of flexibility has saved me time and gas.

But when the stakes are higher, such as high-load-factor maneuvering or some other form of rush job, beware. Such a thing should illuminate a little red warning light that says: Hey, wait…I'm still PIC here. If you can't do it comfortably and confidently, don't try.

My writing about this here won't alter the arc of human nature enough to make any difference, I'm sure. We'll keep on doing what we've been doing. Still, I thought it was worth a mention, just in case.

Comments (20)

In my personal experience, ATC personnel "stick to the book" with near-religious fervor, unless they have extensive personal knowledge of a particular pilot flying a particular type of aircraft. Savvy controllers know how to utilize the skills of certain airmen, just as much as savvy pilots know how to play the “confidence game” that gets them what (to the uninitiated) looks like preferential (read: “expedited”) service. But the game relies upon hard-earned trust, because nobody – pilot nor controller – wants to risk an event that will remain a topic of conversation.

Implicit in all of this, is the controller’s conclusion that what s/he’s observed a given pilot do over an extended period comprises performance that’s well within that pilot’s levels of skill and comfort. If the pilot routinely operates in a manner where the outcome is in doubt, disaster always lurks right around the corner. The greatest danger occurs where the pilot is unaware of just how closely s/he is approaching that tipping point. Eagerness to comply may look like the enemy, but the real problem is ignorance of danger. In this business, knowing your own limitations is the key to survival.

Posted by: Thomas Yarsley | March 7, 2012 6:57 AM    Report this comment

Collective situational awareness and previously established habits complicate the situation. In 22 years of flying (CFI, freight, airline, corporate) I've always been advised which direction to circle from an instrument approach if the controller needs it for traffic issues..e.g circle east for runway X. Otherwise my interpretation (and perhaps that's the problem!) is it's the pilot's decision how to complete the circling maneuver. When instructing I prefer the student overfly and put the aircraft on the left downwind, thus maintaining safe obstacle clearance and putting the landing runway on the pilot's side of the aircraft during IMC circling weather. Recently received one of these "crank it in now" at Tyler, TX during a GPS circling approach. Short story, ATC wanted a circle to a right downwind and we planned an overfly and a left. The controller never gave the instruction and we never asked. Lesson learned. We had the performance and the altitude but a perfect example of how loss of collective situational awareness can precipitate an accident.

Posted by: Shannon Forrest | March 7, 2012 9:04 AM    Report this comment

Paul, an excellent commentary about a terrible tragedy. I think the problem is both what you said, that there is a fine line at low speeed and altitude between great flying and a terrible mistake, as well as the fact that we tend to react instantly to ATC commands. It is almost like a startle reflex. ATC says with urgency in their voice that you need to tighten the turn "right now" and you do it without thinking, notwitstanding good training and knowing better than to do that. All it takes is a few seconds. In this unfortunate case, I think the fact that the pilot might have thought that he was about to make contact with another aircraft on final (the urgency of the controller's commamnd could easily be construed to imply that) might have led him to panic and react by pure instinct to avoid a collision. While I am sure this will be found to be the pilot's fault (and in the final analysis maybe it should be), ATC played a big role here even if not malicious. How we can train pilots to quickly determine what ATC commands can, and should, be safely ignored is a tough one. Unfortunately, I think this is one of those things that can only come with significant experience and is very difficult to teach. Having better SA helps since it makes it less likely that a pilot would panic (or startle) in the situation but there is still the ingrained habit of always complying with ATC. Hard habit to break when exceptions must be made in a split second.

Posted by: Ken Appleby | March 7, 2012 11:38 AM    Report this comment

“My writing about this here won’t alter the arc of human nature enough to make any difference, I’m sure. We’ll keep on doing what we’ve been doing. Still, I thought it was worth a mention, just in case.” – I disagree. Bringing up these scenarios and discussing them repeatedly (online or in person) is probably one of the more effective methods to create that small twinge one should feel to make them question their next move when asked to do something one was not already planning on doing, especially when low to the ground. Your bit of writing about this here won’t fix all of us all of the time but maybe it keeps one more of us from doing something dumb once. If that someone happens to be me, then I would count that as a huge difference.

Posted by: Mark Jensen | March 7, 2012 12:14 PM    Report this comment

Centennial in Englewood, CO looks almost like a carbon copy of Melbourne, and I've made lots of tight base-final turns on my own, and on the request of the tower, to keep away from the busy jet-infested parallel. Wonder how many times I've crept up on that edge unawares? (I've done it once with sweat-inducing awareness.)

Posted by: Patrick Underwood | March 7, 2012 12:53 PM    Report this comment

Good article. There's definitely a disparity between what the controller needs and thinks you can do, what you think you can do, and what you really can do....and I think the disparity could be getting worse… it's up to us to recognize this... the controller can't possibly be able to determine what each individual pilot can do. The other difficulty is when you say "unable", then the controller has to think of another way to resolve any issue, which takes additional time. Pilots need to visit towers, and Controllers need to visit cockpits. I think that will help everyone, at least a little bit.

Posted by: Albert Dewey | March 7, 2012 2:51 PM    Report this comment

Ummm... am I the only only one that believes the phrase "bring it in tight" is non-standard phraseology? What ever happened to "make short approach"?

Posted by: Phil Derosier | March 8, 2012 6:48 AM    Report this comment

Good discussion. My wife and I are pilots, with our 182 hangared at Melbourne, so this recent accident literally struck close to home. KMLB is a busy environment, with lots of training going on at FIT, two parallel runways, and a third runway 50 degrees off the parallels. Add frequent helicopter training, and mix in a half dozen big commercial jet operations a day and - well - you need to be on your toes at all times. The controllers there are great - there are three that we seem to work with most of the time, and we are always appreciative of their professionalism and competence, especially when it comes to mixing all the student traffic in - and keeping them from mixing it up with all the other traffic.

Anyway, my point is that, in such a busy environment, every pilot simply has to be aware of what's going on around him/her, by listening to EVERY radio conversation, not just the one between him/her and tower, and keeping up a constant visual scan for other traffic. It seems that, in this instance, the two converging aircraft ought to have known about the other, and either said something to tower before it got too late, or simply made the PIC decision to make an avoidance move. There is plenty of wide open space off the right side of 9R there for a right 360, by either pilot.

Posted by: Brian Smith | March 8, 2012 7:58 AM    Report this comment

Standard phraseology is limited and sometimes ambiguous (like a pilot saying "unable" will give no clue as to what will happen next). Introducing a one word ambiguous word in a busy situation helps no one. Use very clear English if you think it's needed. "Standard" is a guide, not a limit.

Posted by: Mark Fraser | March 8, 2012 8:03 AM    Report this comment

Back in the '70's when I was an instructor in Norman Ok., the Airforce brought in one of their "mobile" towers to train some of their operators and alleviate the problem of heavy uncontrolled traffic particularly during OU football games. There were manifold problems for example not changing the active runway because the wind was in the opinion of the inexperienced controllers "negligible"...maybe for a C141 but not a student pilot in a cessna 150. The worst case I observed was a student struggling (not my student, btw) with a touch and go ... he had decided to not go and the tower coming on and in a curt and abrupt tone ordering him to "take off...cessna (number) take off"...it turned out all right but the student was completely shaken. We eventually had to have some discussions with the operators and explain that civilian operations were not quite the same as Airforce operations. There were a plethora of examples of them nearly causing disaster after disaster. There were times when the relationship between the pilots who regularly used the field and those tower people really deteriorated. None of the tower people at that time were rated and it showed.

Posted by: Billy Laatsch | March 8, 2012 8:03 AM    Report this comment

As an old(er) aviator once told the tower " You fly that tower, I'll fly this airplane" Be the boss, it's your neck at risk.

Posted by: jack williams | March 8, 2012 8:57 AM    Report this comment

People are surprised when they find out my airplane doesn't have an electrical system let alone a radio. When I'm asked "How do you fly without a radio?". I tell them ... "MUCH BETTER!"

Posted by: Andre Abreu | March 8, 2012 9:03 AM    Report this comment

Key idea: Know your airplane (its limits and yours while flying it) and remember who is in charge of your airplane.

Posted by: Cary Alburn | March 8, 2012 9:18 AM    Report this comment

All good comments. As a tower controller, I could give 3 different Cherokee pilots the instruction, "make short approach" and get three different base legs. I learned to, instead, issue "start your base now" and if that was uncomfortable to the pilot, would get an "unable" and go to plan B. When I'm trying to beat a straight-in with one off the downwind, timing and distance is everything. Sometimes I don't care if the pilot touches down 3000' from the threshold, my required spacing is achieved and both operations are legal. Both of my runways are over 7500' long. A pilot's expectation of always touching down near the threshold doesn't always jive with the controller's need for spacing on the runway. How to communicate both in a short amount of time? Good question. It's made many a long discussion in pilot/controller forums. As a pilot, I never give up my right to say "unable" and neither should you. Remember, most controllers are not pilots, so don't expect them to know what you can or can't comfortably do.

Posted by: David Slosson | March 8, 2012 10:27 AM    Report this comment

A bit peripheral to the topic, but I’ve noted many pilots, including instructors, don’t have any gut feeling for the relationship between tight turn and wing loading even though they understand the principal at an intellectual level.

Racking it up hard for that short approach is fine assuming you have the altitude to spare and are prepared to use it aggressively to reduce the required wing loading/AOA. Unfortunately most pilots don’t practice this type of turn and the sensation of looking out the side window at rapidly approaching ground is too much to bear. Instinct leads them to depart from the coordinated descending turn and a stall-spin results.

Posted by: John Wilson | March 8, 2012 10:28 AM    Report this comment

The concept of the pilot in COMMAND and the responsibility that that position entails is always in mind. I flew into the last Sebring LSA EXPO, I got a "cleared to land" and, in almost the same breath, the tower operator cleared another aircraft to takeoff "without delay A/C on short final." As a controller in my youth (military) this was a red flag and flew accordingly, ready to go aroung if I thought I had to. I landed with incident, but I do consider that the tower operator really did not understand the relative performance of the aircraft he was controlling. MESSAGE: YOU, THE PIC, ARE THE RESPONSIBLE AGENT AND NEVER FORGET IT!!!

Posted by: Kenneth Nolde | March 8, 2012 11:45 AM    Report this comment

Posted by Patrick Underwood on March 7, 2012:

"I've made lots of tight base-final turns on my own, and on the request of the tower, to keep away from the busy jet-infested parallel. Wonder how many times I've crept up on that edge unawares? (I've done it once with sweat-inducing awareness.)"

Someday, APA tower will know what a REAL busy airport is -- at least. There are more planes taxiing for takeoff or after landing at any one time at some of these than during one of their airport's all day

Posted by: Linda Pendleton | March 8, 2012 11:46 AM    Report this comment

"Extend your downwind, I'll call your base".

I've heared that a lot.

"cut it in tight"

Not so much.

Still, hard to imagine a Cirrus pilot loosing the plane to a stall/spin in this situation.

Posted by: Edd Weninger | March 8, 2012 1:01 PM    Report this comment

Until Jet-A hit $5/gallon, I owned and flew a jet warbird out of KSGF. When doing pattern work and the traffic was a bit heavy, the tower controller would occasionally ask me to "keep it in tight for landing traffic on 5 mile final" (which I always appreciated given the 150 gph I was sucking) but often they asked me to extend my downwind. Sometimes they would tell me they would call my base, and sometimes they would ask me to follow the landing traffic, leaving it to my judgement to maintain appropriate spacing. If I lost sight of the landing traffic - not uncommon when 5 miles out on downwind - I'd ask them to call my base. I suspect "keep it in tight" and "I'll call your base" are not necessarily standard phraseology, but we both knew what we meant, knew I could always say "unable", and knew we would each have a plan B. It worked well, and safety was never compromised. Anyone can tell the tower "I've lost traffic - please call my base" and it's a handy trick to keep in mind. (I realize this proably doesn't apply to the KMLB accident, but thought I'd share it anyway.)

The keys are exactly what others here have already stated: Clear communication, situational awareness, and pilot knowlege of aircraft capability.

Posted by: John Johnson | March 8, 2012 1:29 PM    Report this comment

I've never felt threatened by the tower asking me to shorten an approach, because it has always been from near pattern altitude. Having the luxory of excess height that can be easily turned into speed was never a problem. It is that low and slow extended downwind and hence final...maybe with s-turns that I will sometimes decline. My Viking will bite hard if it is allowed to get behind the power curve!

Posted by: Steve Tobias | March 9, 2012 8:50 AM    Report this comment

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