Cant See Nuthin

The zero-zero takeoff is much discussed, but would you ever attempt one? If youre brave enough, how would you go about it?

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The proverbial zero-zero takeoff can be a perennial topic of debate whenever instrument pilots get together. Although you may have practiced them during your instrument training, chances are youve never attempted one since. Perhaps youve been presented with the need, but didnt want to tackle it in real conditions. Perhaps youve been lucky and the need never arose. If you had to execute a zero-zero takeoff, what is a good technique? How would you go about it? And what about the flights necessity makes a zero-zero takeoff a good idea, regardless of

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how many youve flown? Of course, what exactly is a zero-zero takeoff, anyway? Why might we want to execute one?

In real-world conditions, a ceiling of zero feet rarely exists; for practical purposes, theres usually a little “air” between the surface and overlying clouds. Thats one of the reasons the “ceiling obscured” terminology describing a low, indefinite ceiling on the old sequence reports was replaced with vertical visibility in the newer Metar format. Nil visibility is just as unlikely to occur. After all, when was the last time you really couldnt see the hand in front of your face? In fact, and even though it might be legal, we cant support attempting a takeoff in less than at least a few hundred feet of visibility. So, what were really talking about here are low-visibility takeoffs.

There are three different phases to a very low visibility departure: First, youve got to get from wherever youve parked to the runway. Second, youve got to actually perform a takeoff without leaving the runway in any direction except up. And third, youve got to complete a climbout, smoothly making the transition from what visibility you have on the takeoff roll to flying solely on the instruments.

Gettin There

Youve checked the weather. Youve filed your flight plan. Youve got current charts and even a current database in the GPS. Youve reviewed the actual conditions (calm, 300 RVR, VV 100) and assessed the risk. Your plane is in very good condition with about 20 uneventful hours since that annual only two months ago. Youre feeling good about your skills, having just aced your way through a full instrument refresher course at a major simulator training facility. Youre as ready as you can be. Youve decided to go for it. Whats next?

Start with the most thorough pre-flight inspection youve ever done. Carefully check over everything. Make sure the tires are good, your brakes look normal and essentially even, lights work, pitot heat is operative, stall warning functions, and the prop is in good shape. These, of course, are in addition to a more careful version of the normally routine quick look at the engine, wings and control surfaces. You dont want any surprises.

Your first challenge is to get from the ramp to the runway without hitting anything. If youve got GPS-driven live taxi diagrams, youll be way ahead of the game. Either way, before you even start your engine, you should carefully review the airport diagram and map out your taxi route. Plus, if your airport is equipped with the surface movement guidance control system (SMGCS…see the sidebar above), itll be a bit easier to negotiate on the surface.

Once youre ready, start your engine. Review your checklists a bit more methodically and carefully than you might normally: You dont want to be distracted while taxiing by an item you forgot earlier. Give the engine a bit longer to warm up and stabilize before you taxi, just to make sure its going to run smoothly. Complete all your cockpit paperwork and checklists up to the run-up before you start taxiing. If you normally perform a checklist while taxiing, dont. No distractions this time.

If your departure airport is towered, its time to contact ground control (be patient-if the weathers bad enough, they could be napping). Write down your taxi instructions, even it theyre as simple as “Taxi to Runway 22 via right turn on Alpha.” You may have taken this simple route a thousand times, but its going to look a lot different in low visibility and youre going to notice things youve never noticed before-guaranteed. Go slow. You may have to drag your brakes a bit, but do not taxi too fast. Pay particular attention if youve got to negotiate a narrow alley with obstacles. Stay on taxiway centerlines; do not wander. Know exactly where you are at all times while following your progress on your chart. Be aware of the possibility of other traffic and do not assume that anyone else will keep out of your way. Keep your eyes outside as much as possible and keep your head moving to avoid any blind spots in your vision.

At a non-towered airport, make regular position reports, “Hometown traffic on the ground. Fogslicer 45V taxiing on Alpha to Runway 22, passing Alpha-three. Hometown.” If your airport has position-reporting spots on the ramp or taxiway, use them as requested only with ground control, but not with other traffic. With other traffic, use taxiway intersections instead to avoid confusion (“Northeast-bound on Alpha, passing Alpha-three”).

Get to the run-up area. If the runway doesnt have one right at the end, find a proper place to stop for your run-up. Do not do it while taxiing and dont block the taxiway for your run-up. Do your normal run-up, but do it a bit slower and more

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methodically than you might normally do it. Make sure your attitude indicator and all your instruments are properly set. Be sure to get every item and carefully go through your checklist. Dont miss anything.

Launch

If there is any question in your mind that the runway is clear, consider taxiing the full length of the runway, checking for any obstructions. After all, you cant see but a couple hundred feet and if you spot some debris in your way its not likely you could abort a takeoff in time to avoid hitting it.

Youre ready to go. While you did your run-up you monitored tower frequency (or CTAF) for any traffic. Convinced that there is no conflicting traffic, you ask for your departure clearance and get it. Taxi onto the runway with the care you used to get there and line up straight down the runway on the centerline. Do not apply power while still lining up as this may make it more difficult to get properly aligned straight down the runway. Be conservative.

Presuming youve got plenty of runway, theres no need to stop. When youre properly aligned, very smoothly and gradually apply takeoff power. Remember: your propeller-driven plane is going to yaw to the left a bit, unless youre driving a centerline-thrust twin or something made overseas, so be ready with that right rudder. Be extremely vigilant about keeping your nosewheel right on the centerline of the runway. Be sure to perform your “airspeed alive” instrument crosscheck as early as possible. Be ready to abort your takeoff if anything doesnt seem right.

During your instrument training, you may have done a takeoff under the hood, using just a localizer to stay on the centerline. While this is a fine exercise for training with a competent instructor in the other seat, there is an inherent problem: The localizer simply isnt sensitive enough and your skills likely arent sharp enough to keep you on the centerline. Sure, with this technique you can likely stay on the runway, but its also easy to get a little sideways or to adjust too quickly and possibly lose control of the aircraft. For these reasons we recommend that you avoid such a technique and use the localizer needle only as a cross check, if at all. While youre still on the ground, keep your eyes outside.

Have we mentioned that you should work aggressively to stay on centerline? Make constant, but smooth adjustments in the rudder. Avoid getting off centerline in the first place so you wont require any significant, and perhaps disruptive, adjustments. Keep dancing on those pedals, but with a very light touch. That said, dont be afraid to use as much rudder as necessary, just be smooth and gentle about it.

At the proper speed, perform a normal rotation and lift-off, perhaps a bit more smoothly than normal. Dont relax yet.

Wild Gray Yonder

Much has been written about the difficulty of transitioning from instrument to visual conditions and vice versa. It can take a moment to make that transition and get your bearings. For a low-visibility takeoff, one key is consistency. Whether youre in visual or instrument conditions, always perform the same rotation to the same pitch attitude. Do it at about three degrees per second. Sound slow? It is. In a typical GA airplane, your rotation isnt as pronounced as it might be in an F-18, but you should still shoot for a smooth, gradual, slow rotation to your target pitch, whether that pitch is three degrees up in one second or 15 degrees requiring a full five seconds. Dont rush it.

As you lift off, remember to nudge in the correct amount of rudder for the climb. If youve had a crosswind on takeoff, the plane will typically yaw a bit into the wind during rotation. Just maintain that heading, even if its a couple degrees different than the runway heading. This will keep you more-or-less tracking straight out from the runway.

Once the nose rises enough to block your view of even the two centerline stripes that you could see, transition to the instruments. Theres nothing to see outside, for now, anyway, and you should be concentrating on the gauges until you break out of whatever it is youre flying into. When you do transition to instruments, your first glance should be at the attitude indicator. Keep your wings level and maintain your target pitch angle. Do not allow the nose to sink; maintain your climb. Once youre comfortable with your attitude, start working in the rest of the instruments in a normal scan.

Dont try to use that localizer just yet. Remember the cone of silence over a VOR and the needle swing as you pass over it? A localizer behaves much the same and even if youre outbound on the front course (as in a missed approach), youll still get hyper-sensitive needle deflection and a full swing as you pass over the antenna at the departure end of the runway. Just fly heading until youre about a mile from the end of the runway. Then, if necessary, adjust your heading a bit to intercept and maintain the localizer.

Congratulations, youve just completed a low-visibility takeoff! All it took was extra care and vigilance, and a stricter adherence to good technique. Put on your best professional pilot voice and contact Departure Control; youve just gone where some of the pros cant.

Frank Bowlin is a frequent contributor to Aviation Safety, IFR and Aviation Consumer. He regularly practices 500-RVR takeoffs in the CRJ simulator with a rotation speed over 120 kias. Thats enough to teach him hed rather not. When flying GA, he uses that same 500 RVR as his personal minimum.

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