Go? Or No-Go?

It’s often not a simple yes-or-no decision, and the answer can change with the phase of flight.


The primary flight training experience doesn’t adequately prepare most students for the real world of getting from Point A to Point B. Conventional wisdom, often conferred upon us during that primary training phase, teaches us to make an either/or decision about launching on a proposed flight. Unfortunately, the “go/no-go” decision is more complex than that, and the question must be answered using risk management techniques. The answers will be different for departures, while en route and when conducting an approach to the destination.


We tend to emphasize the go/no-go decision as a binary one in which the pilot has no flexibility to manage the risk. In fact, such a decision isn’t a single choice we make once per flight—like flipping a coin—but is a series of decisions throughout the flight. Perhaps another way to think about it is to continually ask “Are we good to go?” at various stages of the flight. Each phase of flight, including pre-flight route selection, carries with it certain risks, however subtle they may be. Factors we should consider in formulating the answers are the same ones with which pilots have been coping since the Wright Brothers, and involve weather, fuel, the aircraft’s mechanical condition and the pilot’s fitness for flight.

Assumptions vs. Real world
In the typical flight training situation, we usually are exposed only to scripted lessons not necessarily reflecting real-world conditions. Think of it this way: Most training flights are scheduled in good weather, and the syllabus rarely calls for flying in marginal conditions or implementing real-deal risk-mitigation strategies like diverts. Many instructors and training organizations might think exposing students to poor weather could encourage reckless behavior after training is completed and the students are on their own. I disagree, and the sidebar on the opposite page has some additional thoughts. Going forward, we need to rethink how we teach primary students the classic go/no-go decision.

For example, we teach the VFR pilot to cancel the flight if weather conditions don’t meet certain criteria. We should indeed be teaching the hazards and consequences of launching at the wrong time, but what about teaching options for dealing with such hazards and mitigate the risk to acceptably low levels? We might teach pilots to consider options such as early or later departures, changing the planned route or other steps designed to mitigate the risk imposed by a proposed flight on a certain day and at a certain time. We might also teach that the key to many successful mitigations is planning your options a day or even days ahead of the planned departure date.

We also should emphasize the go/no-go decision isn’t just confined to pre-departure and takeoff planning. It must continue during the en route phase of flight and on into the arrival/approach/landing phase. The hazards can vary considerably in these three major environments, although the risk management process and resulting go/no-go or “continue/divert” decisions will be similar.

In my view, much of today’s risk-management training emphasizes a mechanical, rote approach to traditional pre-flight planning and risk assessment. In this model, we are taught to check the weather and get a full pre-flight briefing just before we depart. If specific minimums are met, we can proceed; otherwise we cancel. If the answer is “go,” then we pre-flight the aircraft. Again, if a defect is found, it might result in a no-go decision.
Pilots who follow this operating model are likely to find themselves cancelling a high percentage of their planned flights. In some cases, this doesn’t matter if the flight is purely local or recreational in nature.

However, for many of us, myself included, the airplane must earn its keep. If we’re trying to get somewhere for a scheduled meeting or other event, we may need to be flexible enough in our travel plans to allow for delays and changed plans. Accordingly, my approach is to begin the go/no-go and associated risk management process well before the day of the flight. In some cases, it’s necessary to begin many days ahead.

For example, following the standard PAVE checklist (Pilot, Aircraft, enVironment, External pressures), I begin planning a multi-stop flight as much as 10 days in advance. It’s necessary if my goal is a reliable schedule. I’ll start by seeking answers to certain questions: Am I current and proficient? Does the airplane need maintenance? Are all pieces of equipment and radios working properly? Are there any weather systems or seasonal problems—such as icing or thunderstorms—starting to emerge for the scheduled departure day? Do I have backup plans with clients if I have to reschedule meetings?

All of these considerations must be addressed to create any kind of reliable schedule for a lengthy itinerary. As a result of this process, I often find myself changing the planned departure date and leaving a day earlier or later than planned. I believe the results of this extensive planning and risk management speak for themselves. As discussed in the sidebar above, my schedule reliability over the years has been quite high.

En route flexibility
Yes, of course: You should spend a lot of time on pre-departure planning, since it requires departing from a fixed location that could, for example, be subject to weather, terrain or airport hazards. Once launched, however, you have more flexibility to change your route to avoid hazards like weather or terrain. Nevertheless, you still will be continuously making go/no-go, or continue/divert decisions.

Facilitating your flexibility is the wonderful geometry principle that allows you to make considerable dog-leg style deviations from the straight line route—to avoid weather, terrain, or airspace hazards—without adding significantly to the total trip distance. For example, your total straight-line trip distance might be 300 nm. Yet, you could instead fly a two-segment dog-leg displaced 90 miles from the straight-line route to avoid weather or high terrain. Total trip distance would only be about 345 nm. The extra 45 miles flown is about 18 minutes and four gallons in a high-performance single like an SR22, Saratoga, Bonanza or Mooney. This presumes you make your diversion early, yet another reminder of the need for continuous reassessing of hazards and risks.

As you approach the end of the en route phase, your divert requirements become more focused. Why? You’re still presumably headed for that fixed point known as your destination but your routing flexibility is continuously decreasing as you burn fuel and your radius of action gets smaller. Assessing continue/divert options should be done well before reaching your top-of-descent point.

Approach considerations
Yes, the approach and landing phase often presents the greatest hazard and risk challenges to a pilot. That’s because of considerations fundamental to the PAVE construct. This shows up in fatal accident statistics all the time.

Pilot risk factors may be elevated slightly—or even greatly—thanks to the fatigue of a long flight, time spent at altitude or both. The airplane risks may be increased because you may have consumed so much fuel your options are reduced if an actual divert or missed approach is necessary. Obviously, the environment may be challenging if weather has deteriorated more than expected, terrain hazards are present, your late departure or en route deviations now require a nighttime arrival, or instrument approach options are limited.

The greatest hazard and risk challenge likely will result from weather at or near minimums at your primary destination. In fact, the greatest hazard may result if the reported weather is below approach minimums. Air carriers operating under Parts 121 or 135 may not even begin such approaches, but general aviation pilots operating under Part 91 can legally shoot the approach. This “look-see” option has been the undoing of more than a few GA pilots. Yes, it’s true pilots executing an approach at Category A speeds may have more time and opportunity to observe the runway environment—and more likely to be in a position from which a normal landing can be made—than their counterparts flying faster airplanes.

But from a risk management perspective, taking a look almost always is a bad bet. The likelihood you will be tempted to go below minimums is high and the consequences could be catastrophic. That combination of risk likelihood and severity is definitely in the “red” zone on the risk management matrix.

In my view, decisions regarding diversion and “look-see” are best made before reaching the top-of-descent point. This allows you to make a prompt decision to divert to your alternate before the fuel supply becomes critical and further reduces your options. Often, the smartest thing to do is divert to a nearby airport with better weather or lower approach minimums. Don’t forget the rental car quotient, though: Rental car availability isn’t a good reason to take a look, nor bust minimums. But it also can be a side benefit of diverting to a larger airport instead of the smaller one that’s closer to your ultimate destination.

When should you take a look? If the reported weather is at minimums, consider your current risk management profile. If you’re not fatigued, you’re fat on fuel, your required avionics are operating normally, and a potential missed approach won’t add to the risk, by all means shoot at least one approach. On the other hand, if the weather or the approach looks at all dicey (ragged ceiling, icing or convective activity on the approach, inoperative approach lighting, etc.), maybe just pulling the plug now, at altitude, when your divert won’t cost as much fuel, is a smart thing to do. By prolonging the flight unnecessarily, you’re not going to be any better rested, and you’ll have less fuel if something else crops up and presents a delay. Making an early decision to divert—or land short of your ultimate destination—also means you can wait out a changing weather situation and still get to Plan A’s destination, just not at the time you planned.

Absolute limits still exist
Needless to say, there are a number of conditions that dictate no-go regardless of the overall risk level in other areas. For example, launching or continuing into IFR/IMC with inoperative required instruments or radios would be a no-go, as would failure of supporting equipment such as vacuum pumps and alternators. Although this seems obvious to most of us, it always surprises me how often GA pilots will ignore obvious equipment failures and motor off like nothing’s amiss.

It shouldn’t take a rocket scientist—or a formal, color-coded risk-management assessment for that matter—to know that flying into low IMC without a working glideslope or critical flight instrument almost always results in a bad outcome. The Mooney accident described in the sidebar on page 7 certainly falls into this category. But those who violate fundamental operating restrictions, almost always placing the flight squarely in the red part of the risk-assessment matrix, always will be with us.

There may also be such a combination of poor weather and terrain that it is not worth taking the time to do a risk analysis for a flight in a single-engine, non-ice-protected piston-engine aircraft. We face this situation in the Pacific Northwest on some winter (and even spring, summer and fall) days. In this case, scrub the mission. Sometimes the dragon wins. The same’s true for summertime flying in the Midwest, although flying up to the bad weather, landing, waiting for it to blow over, and then flying off to your destination often works well.

Your best defense
When considering go/no-go or continue/divert decisions on your flights, try to envision yourself in a labyrinth, one with multiple pathways and some dead ends. But don’t consider yourself bound by the single pathways that present themselves. Often you can create your own paths through the labyrinth of safe flight, allowing you to reach your destination while maintaining acceptably low risk levels.

Creating these options requires you to plan ahead and remain flexible on departure times, and even departure days, as well as a willingness to change your route. Remember to make your continue/divert decisions as early as possible in order to minimize risks.

Robert Wright is a former FAA executive and President of Wright Aviation Solutions LLC. He is also a 9600-hour ATP and holds a flight instructor certificate. His opinions in this article do not necessarily reflect those of clients or other organizations that he represents.




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