Your Guide To Staying Alive While Flying Low

Why would you ever fly so low? As he explained, it might be necessary to stay that low just to remain in VFR conditions when the weather suddenly collapses and you need to turn around and get back home. And we occasionally participated in Civil Air Patrol search missions, which had to be conducted at low level. Amateur attempts at aerial photography require some expertise in flight at low altitude. Plus, once in a while you just want to go sightseeing instead of riding an electronic course line in the upper airspace. 

I will note here that all of these kinds of missions carry with them considerable additional risk. How much is hard to say, but it's a lot. These kinds of flights aren't common, and yet the accident record shows an inordinate number of accidents blamed on low-level manuevering, or "buzzing," as we often refer to it. Accidents caused by mistakes when maneuvering at low level are usually fatal ones, and the accidents have a common theme: The pilots who were flying low had little experience with low-level flying, they were doing so on the spur of the moment, and they had, hence, not formulated a plan. 

There are also regulatory and neighborly considerations. As my grizzled CFI pointed out, there are some operational differences to be observed when flying at low level. We need to be considerate of other people, such as those living under our flight path. To reduce our noise footprint, we should pull the power back to a low-cruise setting and stay away from built-up housing areas. Even though we're not flying over a town, there can be clusters of developments along highways, and there are isolated schoolyards and even airports that should be avoided. Open countryside is our objective, although we may encounter a farmhouse along the way.

What's Legal?

What are the regulations concerning minimum altitudes to be observed? The "minimum safe altitude" rules have been essentially unchanged since the 1940s, which means they are not always logically applicable in this day and age. But from a legal standpoint, you can fly as low as 500 feet above open countryside or 1,000 feet above congested areas and open-air assemblies of persons, as measured from the top of any obstruction within 2,000 feet of the aircraft. The 500-foot rule also applies to lateral distance from any structure or person when flying below 500 feet AGL over water or unpopulated areas. Even when I learned to fly, these were considered DUMB rules. Flying at 500 feet above the ground should be considered a last resort, reserved for extracting oneself from an emergency bad-weather situation. One should avoid using the ancient rules written for J-3 Cubs when operating faster, less-maneuverable modern airplanes.

What hangar lawyers often fail to recognize is the beginning paragraph of FAR 91.119, which makes the pilot responsible for maintaining an altitude allowing for the safe execution of an emergency landing "without undue hazard to persons or property on the surface" after an engine failure. Regardless of the verbiage that follows it, the FAA expects pilots to add enough extra altitude to carry out the duties inherent in this sub-paragraph (a). If found to be negligent in this respect, you may be subject to a violation. 

Bear in mind that the ADS-B Out data stream is a game changer when it comes to proving culpability. No longer is it possible to contest the opinion of eyewitnesses or the momentary hit of a transponder reply. ADS-B knows all and tells all, right down to ground level. 

Therefore, it behooves us to do our low-altitude flying with regard to today's exigencies. Flying low is still a valid option, but a growing population sprawl and more tender sensibilities require us to exercise due care.

The Way To Do It

As we leveled off at a few hundred feet, my CFI pointed out the diminished perspective afforded by low-level flight. Landmarks came and went quickly---now you see it, now you don't. One needed to keep track of one's location on the chart and, more importantly, what was ahead on the route, because there wasn't much visual warning of its approach. Practically speaking, we would have fewer forced landing options if our engine quit down on the deck, another reason to keep our eyes outside, constantly watching for possible safe havens or avoiding unlandable areas.

To make the task of low-level pilotage easier, a common solution is to pick a road, waterway or rail line going in the right direction and just follow it. That makes it simple to anticipate the presence of the next town up the road, bearing in mind that twists and bends in the track will frequently alter your compass direction. And when you reach a fork in the road, you have to take it, as Yogi Berra said, so make sure you go the right way.

The temptation today, of course, is to just tap a destination into the GPS and follow the magenta line, an unerringly straight path across hill and dale. While sufficient for maintaining orientation, the pink pathway can lead you into places you don't want to traverse. Special airspaces abound, and you'll want to give congested areas and airports a wide berth. While I may create a GPS route when flying at low-level, I'll swing off it as necessary, taking comfort in knowing that it's there on the screen if I get disoriented. 

A much more heightened awareness of the world outside is necessary when flying low. Don't spend more than a few seconds at a time on inside-the-cockpit tasks. A close watch has to be kept on the landscape speeding toward you, which is filled with hazards. Remember the old humorous caution about avoiding flight in the "edges of the air," reminding us to always stay in the "middle of the air." The edges of the air, you see, are filled with tall trees, towers, mountain ridges, buildings and powerlines. All joking aside, never forget that conducting low flight is assuming a greater risk of encountering obstructions. To manage this risk, keep your eyes outside nearly 100 percent of the time. If you have something important to do on your instrument panel, climb up to a safer altitude while taking care of it.

Flying low means staying away from unwelcoming localities. Airports, even little-used ones, should not be overflown at traffic pattern level. Take up a diversion heading that will avoid them by a couple of miles, and make a traffic advisory call to alert local planes of your intentions. Otherwise, an inbound aircraft might think you're approaching to land and will follow you off into the boondocks before figuring out that you're only passing through. Remember, plan ahead for airport encounters; you're not going to see the runways and hangars from a distance when you're down on the deck.

Consider that you have limited communication capability when you're flying below the horizon. VHF frequencies are essentially good for line-of-sight reception, so if you need to talk with someone at any distance, you'll have to climb back up to a more reasonable altitude. Radar contact will also be lost most of the time; even if you see the transponder's reply light flickering, you're not really being painted when out in the low boondocks.

You're Not Alone Down There

The fatal accident involving two employees of Icon Aircraft in 2017 should serve as a wakeup call for the risks of flying low. The pilot, a high-time test pilot with tons of hours and a strong knowledge of the terrain, chose the wrong canyon to fly into at low altitude. The one selected had no outlet, and by the time he realized it, there was no escape. Flying low carries risk, and flying around high terrain carries even greater risk, far greater.

It's not just terrain. Tall towers are an ever-present hazard when flying low, and not all of them are charted; new ones crop up all the time. GPS alerting may not help much because you're already operating in a continuous terrain-caution condition. The solution is to stay high enough to avoid all but the most unlikely super-tall obstructions by planning in advance. Watch for the large minimum-clearance altitudes on the sectional chart, which change with every lat-long grid, and when you see that number increase, take action. The larger obstruction symbol on the chart is only used when the tower pokes above 999 feet AGL; a 950-foot tower gets the smaller symbol, but it'll kill you just as dead if you hit it.

In addition, avoid flying in the bottom of narrow valleys and canyons; stay at ridge level or above. There are often powerlines strung across the valleys that sag quite low between the supporting structures, so make sure you have clearance above the poles and towers. 

Remember to be considerate of the effect of the noise you're making. You may be insulated by the speed of your passage and your noise-canceling ANR headsets, but people under your flight path are not. Rattling windows as you pass by is not a friendly gesture. If you have a constant-speed propeller, dial it back to a low-rpm cruise setting. Most of the annoying noise impact from a light airplane comes from the propeller tips stirring up the air at transonic speed. The fun of flying low is enhanced by reducing airspeed for sightseeing. High-performance, heavy-horsepower airplanes are not suited for such cruising; flying at 3 miles per minute turns the landscape into a blur, so you'll probably want to stay above 3,000 feet AGL if flying such an airplane.

And should you feel the urge to take a photo or two, don't do it at low altitude, where flying the plane deserves your full attention. 

Knowing how to manage the risks and challenges of low-level flight is a useful tool for your bag of flying skills, but it's one that can't be taken lightly.