Saving The Approach

Its all but settled wisdom that a good landing is always preceded by a good approach. But define good? Does “good” mean you had the numbers nailed from the point you turned into the downwind? Or can you call an approach good if you sailed over the numbers on speed and kissed the pavement to make the first turnoff, even though you started too high and too fast and got behind on flap and gear extension?

The second answer is the best one, in our view, because it implies two things: airmanship and judgment. The airmanship part means you have the skill to coax the airplane toward the right speed and attitude to land safely if not prettily. Judgment means you know when youre too far outside the envelope to even try to salvage an approach.

In this article, well examine both-the skill set and the judgment necessary to pull an acceptable landing out of a flaming mess of an approach. Skilled pilots do this everyday and although your first instructor advised a go-around when in doubt-good advice, by the way-you can whittle that doubt into confidence instead.

Well look at both visual and instrument approaches. Interestingly, they go awry for many of the same reasons. The overarching one is lack of planning due to flagging awareness of where the airplane is and what it needs to be doing and when. Filling in the details, this means the airspeed is too high or too low, the altitude is wrong or the airplane isnt where its supposed to be with regard to the pattern leg or approach course. A related oversight is configuration: You overlooked the flaps or the gear entirely-it happens-or you deployed either or both too soon, complicating airspeed and altitude considerations.

Lets consider the visual approach first. We dont have hard data on this, but from years of instruction, we would surmise that a large percentage of visual approaches go bad at or even before pattern entry.

Think about it. All of us have entered the pattern too high and tried to bleed off the altitude while motoring toward the base leg from the downwind. In a draggy fixed-gear single, this isnt so difficult. In the go-down/slow-down mode, you might be only 10 knots or so above your reference speed. Thats easy enough to scrub off on the base leg.

But in a faster retractable, its not so simple. If you blaze into the pattern above V_LO while still trying to slow down, youre setting yourself up for a too-fast final at the least and a gear-up landing at worst. Its best not to get there in the first place, but weve all done it.

In the fixed-gear single, one strategy is to trade pattern segment length for a little deceleration. When youve entered the downwind too high and too fast, bring the power to idle and hold the nose near the horizon to bleed off the speed at least into the flap range. You may have to extend the downwind leg a little until the speed is closer to normal, get the appropriate flaps out, then continue with the pattern, adjusting the speed on final as necessary.

If youre still too high and too fast on final with all the drag out, a slip is the best option. Without worrying much about your slightly too fast speed, aggressively slip down to or a even a little below what looks like a reasonable visual glide path. When you break the slip, still a little below the path, pitching up will bring the airspeed back into the box as you reintercept the right visual glidepath.

Alternatively, if sinking slightly low doesnt suit, you can easily adjust speed in the slip, slowing airspeed even as you increase descent rate.

If youre so high and so fast that you need to hold the slip until just before the round out-that happens, too-youll need to manage the speed more carefully with some pitch adjustment in the slip. Theres a danger here, however, and it can lead directly to the most common type of accident in general aviation: runway loss-of-control. These accidents are more frequently the result of touching down with too much speed rather than too little. And too much speed is a common problem in slips because when the airplane is cranked around off axis, theres an understandable tendency to add five knots for the wife and five more for each kid.

This is the judgment part. If it feels uncomfortable or looks like its not going to work, it probably wont. Consider the go-around. The good news is that you dont have to make the go-around decision until the bitter end. Weve all had the experience of a high approach that looks impossible but looks a little better 100 feet lower and perfectly normal when its time to flare.

Given the number of runway excursions we see in the NTSB files, this is not a judgment everyone can make easily or correctly every time. It requires a higher level of the same perception you use in pulling into traffic on a busy highway. Your brain makes unconscious calculations based on perceived speed, distance and closure rate. Such calculations rely on previous experience in similar circumstances, but if the current conditions are different-a slight tailwind, a wet or icy runway, marginal brakes-the next sound you hear may be rending metal.

The approach salvage is more complex in a faster airplane or one with retractable gear. Theres a reason for the FAAs insistence that pilots have endorsements for complex aircraft. Given the laws of aerodynamics, every retractable made can go down and slow down at the same time-if it has enough altitude and distance to do that. From pattern altitude, however, youre unlikely to have enough of either.

If the botched approach is too high and so fast as to be above V_LO, options are limited if youre close to the runway. Setting the prop to flat pitch and the power to idle will add some drag and will help, but it might not be enough. If youre close to V_LO, a slight slip and pitch pull may be enough to get the gear down.

In most retracts, once the gear is down, the drag increases exponentially and full flaps can follow. In a scenario like this, we think adding the flaps in increments is counter productive. In fact, for light aircraft, we cant think of any good arguments for incremental flap deployment, other than major trim excursions. In no single of which were aware will electric-operated flap extension outrun the pilots ability to keep up with trim; even manual trim.

Actually, there is one argument for incremental flap deployment. Some pilots like to use a notch of flaps on instrument approaches for speed control. This is a matter of personal technique, but we think the better way is to fly the airplane clean until breakout, then extend the flaps all at once.

Once a retract is fully dirtied up, its not much different than a fixed-gear airplane. And despite some pilots claims to the contrary, theres no reason you cant slip a heavy single or even a twin, provided there are no fuel unporting or elevator-blanking issues in the POH. While heavier airplanes take more manhandling to muscle into an approach, they respond just as lighter airplanes do.

While on the subject of slips, one good alternative to them that pilots tend not to consider is the long landing on a runway that allows for it. The classic scenario is the too-high, too-fast approach that whizzes over the numbers 50 feet high. But on a 4500-foot runway, there will be more than enough pavement to slow down and land long, even using the full length if necessary. (They dont charge you more for that.)

Depending on the airplane and the speeds in question, this may be acceptable on a shorter runway, too. But it will require a realistic feel for the airplanes stopping distances. Notice we said “feel” and not “knowledge.” When youre sighting down a runway toward its rapidly approaching end, measuring distance isnt an option, but judging it relative to your eventual touchdown speed is.

Which goes awry more often, a visual approach from the pattern or an instrument approach to a cloud-bound runway? We have no idea, frankly. But any CFII has seen enough of the latter to have an opinion.

As with visual pattern approaches, instrument approaches unravel for the same reasons: lack of situational awareness, poor speed control and altitude excursions. In one form or another, these can lead to course excursions and the classic needle sword fight on an ILS.

Throw in confusion over procedures and, lately, uncertainty in setting up avionics far enough ahead of approach entry and there are yet more reasons.

As we reported in the January 2010 issue of Aviation Safety, most approaches resulting in accidents go bad in the vertical dimension-and you can guess that no one gets into trouble for being too high. The only cure for being too low on an approach segment is to climb without delay. This introduces speed control issues but if youre sharp on the gauges, you should be able to initiate a minor climb-say a couple of hundred feet-without upsetting your dialed-in approach speed.

An example? Dipping below the intermediate altitude on a non-precision approach or even the final segment as youre flying toward the missed approach point looking for the runway. To salvage this, merely add a little power and pitch up. You dont need to zoom back up to altitude, but rather inch back up. Maintain your approach ref speed within five knots or less until youre back where you want to be, then remove the added power and restore the pitch attitude.

The judgment call here relates to how far you are below the published altitude and on which approach segment you are. A hundred feet low with a null descent rate on an initial leg is one thing; 200 feet low at 500 fpm quite another. The latter may require an immediate missed approach, especially if youre on a final segment with minimum obstacle clearance.

These come in two types: bad angles and tight turns. Controllers have specific standards for vectoring airplanes onto the final approach course and they rarely miss their marks. But rarely isnt never and, like pilots, controllers occasionally lose the bubble or get flummoxed by the wind.

The standard ATC vector directs the airplane to intercept the final approach course at a point at least three miles outside the final approach course at an angle between 30 and 45 degrees. In the real world, the angle can be sharper or shallower and the turn can occur much closer to the FAF.

This presents a unique challenge to handle several things happening at once: On an ILS, the course indicator will swing in rapidly and the glideslope needle may already be centered or indicating fly down. If your speed is too high and/or the gear is still in the wells, this one may not be saveable. You may have to concede defeat and ask ATC for another vector.

If it is savable, a slower rather than a faster speed will make it so. What you need to center the needle without undue theatrics is a smaller turn radius to keep from overshooting the turn onto the final approach course. At a higher speed, youll need a steeper bank angle to make the intercept, while at a slower speed, the bank angle can remain reasonable-say, no higher than 40 degrees or whatever value youre comfortable with.

But this sort of maneuvering is a close thing; it can just as easily go bad as go right and the payoff-avoiding a missed approach-isnt necessarily worth the risk of an upset in IMC or even an ugly, marginally controlled save that is more luck than airmanship.

While recovering a botched approach to a safe landing is a good skill to have, its also true that the take-it-to-bank strategy is a go-around or missed approach. Unless the airplane is on fire or a passenger is in extremis, taking it around for another try is never the wrong option.

And those who have done this-and we daresay thats everyone-know one thing: The second try is quite likely to be perfect because although making mistakes is inevitable, making the same one twice on the same day is improbable.