ILS approach at night

As the Cessna 152 carried us toward a neighboring airport, the glow from a full moon provided comforting illumination of the muted pattern of farm fields below. Dirk and I were on a mission. He needed to get better acquainted with night landings, and I, although current, could use some extra night time myself. We couldn’t have picked a better evening, even though there was a bit of wind shear, with near-calm winds on the surface but an estimated 20 knots blowing above 500 feet AGL. But the air aloft was still, and visibility was 40 miles or more.

The beckoning beacon soon hove into view. Someone had already keyed up the pilot controlled lighting (PCL) system, so the runway’s outline stood out from the moonlit landscape. We eased into the unoccupied pattern and started a standard approach from abeam the threshold lights. All was going well as we turned base with partial flaps extended, and I cautioned Dirk that we might find some sink on final, and to be ready to add power.

Sure enough, the green lights seemed hard to reach as we ground toward the runway. With some extra throttle, we soon saw the runway numbers slide under the nose and the first landing was in the bag. Now to get a couple more, just to make sure that wasn’t beginner’s luck.

Dirk taxied back for a standing-start takeoff; I noticed that there was a black void off the approach end of the runway, where no ground lights could be seen. The nearest street was perhaps a mile from the airport perimeter. We lined up and blasted off with all the alacrity of a fully-laden Baby Cessna, climbing slowly over the suburbs on the departure end. A bit of rough air signaled the transition into the wind shear and our ground speed visibly slowed.

ILS approach at night

What’s in that black hole around the runway? Best to stay high if you’re not sure.

Once on downwind, Dirk reactivated the lights with seven clicks of his mic, just to make sure the PCL timer didn’t expire at a bad time. Once again, the green threshold lights seemed far away on base leg; I checked our altitude and called for additional power, telling Dirk to keep his speed up, fine-tuning for the change in trim that power application brought. He turned final, rolling out with the green lights right above the cowling.

He was doing a good job, I thought. I glanced toward the runway lights, noticing a strange flickering appearance in the bar of green glowing lamps. “Dirk,” I said, “pull up, we’re too low.” Just then, there was a sickening crunch from his side of the aircraft, then silence as we floated down to the runway. “I think we hit a tree,” he said. “I saw it sticking up just as we went past it.”

We taxied to the uninhabited ramp to check the aircraft for damage. The only visible sign of our near-disastrous contact was a new wrinkle in a wing skin; there was no tear, no oil-can deformation, no sign of impact on landing gear or strut fairings. Evidently we had encountered a small tuft of brush, sticking up from the screen of vegetation that was blocking all lights in that sector.

With the second landing of the evening forever imprinted in our memory, we elected to fly a couple more circuits and go home. Dirk assured me that he’ll never, ever, let the green threshold lights rise up above the engine cowling on a night approach. He now knows what a change to flickering threshold lights mean; you’re looking at the lights through tree branches. We agreed that there will always be plenty of runway available after clearing the threshold lights and numbers; there’s no need to put the airplane down in the first few hundred feet.

Would it have been better to leave the airplane and call for a ride, rather than fly it with a chance of internal damage? If there been more evidence of a harder impact, we would have done just that. However, the creasing in the skin was slight enough to give us a sigh of relief. The wing would require only cosmetic repair.

The cause of the incident was, as is nearly always the case, a combination of uncorrected errors, creating an accumulated chain resulting in a breakdown of safety. First, we failed to fully take into account the effect of subsiding headwind as we descended on the approach, correcting too little, too late. Second, we didn’t pay attention to the ominous unlit blackness out there on short final, where something was clearly taking the place of flat, moonlit farm fields. Third, we fixated on the target, ignoring the rest of the indications, like the dwindling altitude, unmoving lights that should have been dropping down under us, and airspeed loss. Without including any one of the mistakes, we could have cleared the treetop, as we did on the first landing.

Target fixation is a common military hazard associated with strafing runs during ground support missions. The pilot is so fixated on his run toward the objective that he fails to pull out in time, pulling up too late or not at all. A night landing’s lack of visual cues tends to promote focusing on the primary objective—the runway threshold. And as our tree-topping event showed, that can nearly prove fatal.

Avoiding such fixation during a night approach begins with knowing that the danger exists and making sure you keep watching other inputs, like the motionless point in the windscreen that predicts your impact point, along with an altitude readout that keeps you above all obstacles by a comfortable margin. If you don’t know that target fixation exists, you won’t know to avoid it.

In Dirk’s and my case, we were very, very lucky. Striking the bough another foot lower, or further inboard, could have spun us out of control and into a piled-up crash. We got away with a hard, expensive lesson, and sharing it is our obligation to all our fellow pilots.

8 replies
  1. Cary Alburn
    Cary Alburn says:

    If you have the luxury of some form of vertical guidance, whether it be an ILS glideslope, an RNAV LPV or LNAV glideslope, or visual indicators—PAPI or VASI or variations of those—then use it. Although the instrument methods are theoretically for IR pilots, VFR-only pilots should be taught and learn how to use them.

    If none of those are available, my personal rule (as taught to me by my first CFI over 47 years ago) is not to descent below 400’ AGL on final until the landing can be safely made without power. That also means landing somewhat down the runway, not on the numbers, using the thousand foot markers as the touchdown point if available or if not, then a point within the first third of the runway but near the end of that distance.

    So much of the visual cues we rely on during the day are invisible at night, as are almost all obstacles. So night landings have to be done in such a way that we can avoid creating the author’s scenario, or worse.

  2. Mike Sheetz
    Mike Sheetz says:

    I almost always approach a bit high. I can quickly loose altitude with a slip, but a surprise change in wind may not be recoverable with power in a heavily loaded aircraft. Landing in the first third of a runway can almost always be assured if you work at it. Night flight is a different “animal”. Even if being high one can usually manage getting on the runway within a reasonable distance. Go around is almost always an option.

  3. Warren Webb Jr
    Warren Webb Jr says:

    Excellent article. I also had some approaches at night that could have been better. Unfortunately some techniques that are simple and safe during the day can be very dangerous at night. So in a way, they should never be taught – only methods that are equally safe in day and night should be. Now I use the fourth set of white runway edge lights as my night aiming point. When turning from the downwind, I keep that turn close to a 45 degree angle to my aiming. I reference the altimeter base to final to help me confirm I’m at least 400-500ft above the runway. On final, I remember the most basic illusion and accept that the approach at night seems to be steeper than normal. I make very sure the fourth set of white runway edge lights are motionless, and all lights closer are moving downward in the windshield, especially the green lights – for some reason at night they become an insidious and incorrect reference point. Resist the temptation to fly toward them. As Charlie said they and all lights before my aiming point should slide under the airplane.

  4. Larry
    Larry says:

    In 1986, a C172 making a night approach to the Ontario, CA airport wound up flying into very tall power lines, getting caught and hanging upside down 90′ up for four hours. Those lines had to be de-energized before a giant crane rescued the pilot and passenger. At a safety briefing at Edwards AFB, the Flight Surgeon explained that there is an eye-brain function that seeks to fly a constant radius circular path vs a straight line at night. The above methods for ameliorating that are good ways to combat it. It gets worse …

    A couple of years ago, a pilot at my local airport wound up too low on DOWNWIND in a pitch black environment and hit a tall pine tree. He survived but the damage to the C172 was substantial.

    If flying is a terribly unforgiving act, flying at night is terribly unforgiving by an order of magnitude.

  5. Theo Kalman
    Theo Kalman says:

    The above comment about flying being unforgiving strays somewhat from the actual famous quote – “Aviation in itself is not inherently dangerous. But to an even greater degree than the sea, it it terribly unforgiving of any carelessness, incapacity, or neglect.”

  6. Paul
    Paul says:

    I had the unfortunate experience to watch an AH1 G Cobra Attack Helicopter on a night target attack get fixated on his target and fly into it. Last 2 rockets were fired just before he hit the ground.

  7. Kim Hunter
    Kim Hunter says:

    During the 1960s controlled flight into terrain, during night VFR approaches, accounted for an alarming number of commercial airline mishaps. Better crew training, equipment and CRM procedures have just about eliminated this from part 121 operations.

    But, as you point out in your timely account, these approaches can still pose a credible threat to GA pilots under the right circumstances – wind shear being high on the list.

    Thanks for the article.

  8. John
    John says:

    Several years ago a C182 on approach into Cashmere, WA and flown by a very experienced pilot struck the top of a tree directly aligned with the short,1800′ runway. Target fixation? A sudden gust that caused the plane to suddenly drop several feet? Sun glare was suggested in the NTSB report. An hour or two prior to the accident I spoke with the airport manager about weather. She told me the winds when I called were strong and squirrelly. The accident occurred at 19:07 on 28 June 2007. Sun glare on runway 25 was likely brutal about that time of day, and the approach into that runway is steep. IMHO, landing directly into the sun requires just as much care, planning, and attention as any VFR night landing.

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