On instruments: Holding dilemmas

First of all, you’ve been issued a holding clearance for a good reason. Usually, something is causing a delay, such as low instrument meteorological conditions, a high traffic volume, or—at nontowered airports—a pilot’s failure to cancel an IFR clearance after landing at your destination. All three of these conditions are good reasons to assume that weather is the root cause. But you should know that already, having stayed up to date via your FIS-B updates or ATIS checks.

What should be your first concern? Fuel status, of course. If the reason for the delay is that the weather is so low that inbound flights are executing missed approaches, then you have to wonder if subsequent, time-consuming missed approaches will cause your expect-further-clearance (EFC) time to be pushed back. After all, low IMC forces controllers to adhere to strict rules. Any flights departing from your destination must be properly separated from the airplanes on missed approach procedures. There will be no visual approaches, so there are no shortcuts or vectors to final to speed things up. In hard IMC you may be part of a stack of airplanes holding around the same fix. As airplanes are cleared to land, ATC “shakes the box” and clears each holding airplane to progressively lower altitudes—until it’s your turn to shoot the approach. All of this takes time.

Will you have enough fuel to wait it out for your turn? Better check your EFC and takeoff times from your departure airport (you did write that down, or use a timer, no?). A little math will tell when you’re likely to reach “minimum fuel” status—meaning you’ll have enough fuel to carry out an arrival and approach to your destination using your assigned routing, and land with legal fuel reserves—if there are no delays. ATC is supposed to advise you if a hold is likely to last more than an hour, and issue instructions just in case. But can you afford to mill around for an hour, then, say, divert to an alternate and still land with 45 minutes’ worth of reserve fuel? If your answer is no, then this is the time to refuse the clearance and ask for a diversion. If the situation is critical, don’t hesitate to declare an emergency.

Will you have enough fuel to execute the miss, climb at high power back to the top of the “box,” and wait for who-knows-how-long for your next shot at the runway?Remember, your EFC says nothing about which approach will be in use. This also should factor into your decision-making. The ATIS may say that one approach is in use, but you may have to maneuver to a different runway’s approach. How much more time will that take? Should you load or activate the approach mentioned in the ATIS? Probably not. If you’re shaken to the bottom of the “box” and it’s your turn, you don’t want to be distracted at such a tense time. The weather is already low, as is your altitude. This may not be the best time to be plugging a newly issued approach clearance into your avionics.

And what if, after reaching decision height/decision altitude or minimum descent altitude, you see nothing and have to execute a missed approach of your own? Will you have enough fuel to execute the miss, climb at high power back to the top of the “box,” and wait for who-knows-how-long for your next shot at the runway?

A word about the weather. If it’s so bad that below-minimums weather lasts for hours (or days), then a second approach may well end with another missed approach. Tension and fatigue by then will have taken their toll. Second or third approaches have ended in accidents. Warm and stationary frontal weather—especially in the fall and winter months—are notoriously slow movers, so don’t expect any sudden improvements. And was any icing forecast? If so, you shouldn’t have taken off in the first place if you’re flying a typical piston single or twin.

Instead, plan for an early diversion out of a lengthy hold. Just make sure that lower ceilings and visibilities aren’t going to challenge your fuel reserves. Request a diversion, and ATC should be able to clear you out of the holding pattern and into better weather. Your preflight planning should already have told you exactly where the good escape routes are.

For turbine pilots, the standard operational advice is to stick with fuel planning that relies on the National Business Aviation Association’s IFR fuel reserve formula. It’s a conservative planning scenario that anticipates:

• Missing the approach at the destination.
• Climbing to a holding fix for a five-minute hold at 5,000 feet.
• Leaving the hold and cruising at long-range power to the alternate (this may be 100 or 200 nm away).
• Shooting an approach at the alternate.

This strategy is designed to leave you with 30 minutes’ worth of fuel after landing. But I see a catch. In this scenario, the hold occurs after shooting the approach, not before—which is the situation we discussed. With more fuel burned before the first airport of intended landing, there’s obviously less available for flying to such distant alternates with safe fuel reserves. The seed of an eventual fuel emergency is planted sooner in the flight, not later.

Which brings us back to the EFC time. If ATC doesn’t give you one, then ask for it. It’s your lifeline in case you lose communications when you’re stuck in a hold—or anywhere along a route plagued by solid IMC. Yes, ATC should give instructions if a hold is expected to last more than an hour, but if your EFC is up, there’s no word from ATC, and your calls aren’t answered, then lost communications procedures kick in. First, squawk 7600 and see if you can hear ATC trying to reach you. Try turning up the radio volume or turning down the squelch, or selecting another radio. Try listening on a nearby VOR’s signal. You may be able to communicate with ATC using transponder codes.

If you have an EFC time, and the holding fix is associated with an instrument approach, begin your descent and approach as near to the EFC time as you can, and land. Without an EFC time, and if the holding fix is not a fix from which an approach begins, fly to one that is—and begin your descent or descent and approach as close as possible to your planned or amended estimated time of arrival at the destination.

Those are the rules, but if you go radio silent while holding in a stack in IMC, what then? Descending through the stack is a very bad idea for obvious reasons. And if you do make it out of the stack, what route do you fly? Your assigned, expected, or flight-planned route (to your alternate, in the absence of the first two)?

There’s plenty of food for thought here. What would you do—apart from conjuring up an airport in some good VFR weather? A full load of fuel would also be nice.

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