The vexing problem of runway excursions after landing isn’t going away—these aircraft accidents continue to happen. To help its members, the Citation Jet Pilots Owners Association (CJP), in partnership with the industry, commissioned a study and simulator testing not only to assess pilots’ existing performance but also to develop a more logical and realistic method of evaluating the stability of approaches.
Results of the study exceeded CJP’s and study partner research group Presage’s expectations. Research results were released in October at CJP’s annual convention in Palm Springs, California, as the Safe to Land initiative. The study was funded by the CJP Safety and Education Foundation, FlightSafety International, Textron Aviation, Garmin, NBAA, and the Air Charter Safety Foundation.
“It’s a very simple, repeatable technique,” explained Richard Meikle, FlightSafety International's executive v-p of safety and regulatory compliance. Simulator testing, which FlightSafety donated as its contribution to the program, showed that pilots understood and picked up on the technique quickly, appreciating how it applies to their typical single-pilot jet operations, as opposed to adherence to multi-pilot, big-airplane stabilized approach procedures that don’t always translate to smaller airplanes. In fact, the new CJP-derived approach procedure could be used with almost any type of airplane.
To conduct the study, Presage created a survey asking CJP members about their decision-making process during stable and unstable approaches. The responses from more than 200 CJP members informed the next step, where a 10-member working group evaluated the study’s results and developed new instrument and visual approach procedures and callouts.
Using FlightSafety’s Citation simulators at its Wichita learning center, 22 CJP members flew more than 200 approaches to evaluate the new procedures and fine-tune the Safe to Land initiative.
In January, CJP began releasing the Safe to Land programming, which includes video training, a bimonthly newsletter, a new cockpit briefing card, and a dedicated page on the CJP website. "We anticipate full integration of these new standard operating practices (SOPs), including training to them with a new [FlightSafety-developed] curriculum for our simulator sessions, to take the next 12 to 18 months," said Charlie Precourt, chair of the CJP Safety and Education Foundation’s Safety Committee. "We believe the Safe to Land initiative could be a real game-changer for the light jet community.”
Precourt and the safety committee originated the discussion about stabilized approaches and the CJP SOPs, which ultimately led to the Safe to Land initiative.
“One of the things in [the SOPs] that’s always bothered us has been the criteria for a stabilized approach,” he said, “upon which is the premise that if you aren’t [stable], you go around. And most pilots will tell you the criteria are not anything they’ll buy into.”
In practical terms, while stabilized approach criteria seem like a good idea, what this becomes in reality is something like this going through a pilot’s mind on approach: “At 500 feet, if I’m five knots fast, I ain’t going around. I’ll fix it.”
Precourt said, “I was always bothered by that.” And when he was exposed to the Flight Safety Foundation’s landmark study on Approach-and-landing Accident Reduction (ALAR) through his work on the NBAA board, Precourt met some like-minded safety experts, including Presage president and co-founder Martin Smith. The ALAR study “really resonated with me,” Precourt said. “There’s stuff that happens at 400 to 500 feet, and how do we deal with it? So that’s why I jumped on it and went back to the safety committee. That’s how we got started.”
Anatomy of an Approach
Put simply, the results of the CJP/Presage study showed that the current criteria for a stable approach contain an inherent problem.
Typical stable approach criteria call for achieving a stable approach at 1,000 feet above field elevation (AFL) during an approach in instrument meteorological conditions (IMC) or 500 feet AFL in visual conditions (VMC). At those “approach gates,” a Citation CJ3, according to the CJP SOPs, should be: landing gear down, speed brakes retracted, flaps set; airspeed at Vref -5/+20 knots; descent rate maximum of 1,000 fpm; power stabilized at an appropriate setting for the descent rate; and no more than a half-scale deflection on horizontal and vertical guidance indicators.
The CJP SOP guidance, like most stable approach recommendations, calls for the pilot to evaluate whether the airplane is stable—meaning it meets the above parameters—at 1,000 or 500 above field level and, if so, to continue the approach and land or, if not, to go around.
But runway excursions still happen. According to CJP, “Many runway excursions result from approaches that are either unstable or become unstable after the approach gate at 500 feet.” In other words, pilots might meet the stable approach criteria at the 1,000- or 500-foot gate, but then become unstable after that, and that increases the chance that an excursion might occur.
What the research found was that it doesn’t make sense to have the goals and limit points be the same. The goal is to be stable at 1,000 or 500 feet but what if that is the case and then the airplane becomes unstable after that. How unstable is too unstable? Can the approach be salvaged? If so, what are the criteria and where would they apply to decide if completing the landing safely is even possible?
Let’s say you’re flying a perfectly stable approach in IMC and break out at 700 feet with all the criteria perfectly met at 1,000 feet and still in alignment, so you continue. As you cross the runway threshold, a gust pushes the airplane sideways. You already met the stable criteria at the 1,000-foot approach gate and decided to continue. Does that mean that no matter what, you are going to be able to land safely?
Not necessarily. What if the sideways gust blows you so far off the runway centerline that you would need a fairly steep bank to get close to the center? What if the airplane balloons a little because of an updraft and now you’re running out of runway?
What CJP and Presage found is that it makes sense to set limit boundaries beyond the approach gates; these limits serve as the final decision point where a go-around must happen. The area between the gate and these limit points or boundaries can be considered as a “yellow caution zone,” according to CJP, “where we can continue and attempt to correct an instability that doesn’t quite meet the goal while committing to discontinuing attempts to ‘fix it’ upon reaching a new ‘limit point.’”
So instead of trying to salvage an approach that becomes unstable after the approach gate without any clear decision point, the CJP Safe to Land initiative applies strict limit points that help pilots determine if the approach is salvageable and when to go around.
Having participated in some of the simulator flying—not as an official part of the study but for observational purposes—I can see how the new process makes deciding whether to continue and when to go around much easier, eliminating much of the ambiguity that can be present during approach and landing.
Prepping for Simulator Trials
“We’re looking at decision-making below 1,000 feet,” explained Presage’s Smith. “This whole program is about building discipline and confidence.”
In a 2017 Flight Safety Foundation study, the Go-Around Decision-Making and Execution Project, which was conducted by Presage, 83 percent “would be mitigated by a go-around,” he said. At first glance, he explained, it might seem that encouraging pilots to go around more would be the obvious solution.
On average, only 3 percent of unstable approaches result in a go-around. “The consequences are, year-over-year, approach and landing accidents [are] making up about 65 percent of all industry accidents, with a large percentage of those preventable with a decision to go around,” according to CJP. But go-arounds are inherently risky, and thus, “In fact, the go-around phase of flight is more fatal than all other phases, when comparing an equal number of flights occupying each phase.”
Of interest, Presage found that in an unstable approach, Smith said, “The closer you get to the ground, the higher the risk, it’s basic logic. [For] the go-around itself, though, the risk stays fairly constant. Because it's not a function of elevation or height above ground.” Pilots who have tried going around from a higher altitude often find that it’s a messy outcome, perhaps because pilots mostly train to do go-arounds from lower altitudes, over the runway after not being able to complete an instrument approach.
Given the higher risk of any kind of go-around, Smith explained, “we want to be able to say we don't want unnecessary go-arounds to happen. That there is a sweet spot where [we’re] managing the instability to a lower level while mitigating the risk of the unnecessary go-around. That's the sweet spot; for this organization, they picked 200 feet.”
This was a result of the CJP member survey, which included 210 respondents who answered 64 questions. Ultimately, the majority say that they are comfortable correcting instabilities by 200 feet.
Based on those results, Presage designed the simulator portion of the study to figure out the most important factors that CJP members should consider at 500 feet, keeping it to two or three. There were 22 pilots in the study, eight in a control group flying current procedures and 14 in the test group flying the new Safe to Land procedures. They flew more than 200 approaches in FlightSafety’s simulators using New York's East Hampton Airport (KHTO) and its RNAV Y approach to 4,255-foot Runway 28. FlightSafety programmed the simulator to allow the instructor to insert instabilities ranging from minor, correctable deviations to some that required a go-around, based on the stable approach goals and limits derived from the study. The deviations were randomized so even the instructor and Smith didn’t know what was coming until opening the package for each subject’s flight.
Smith also introduced the concept of warnings to the pilots, which is highlighting an instability out loud and saying a word that acknowledges it and indicates that some kind of correction is underway. For example, at 700 feet and if speed is more than 20 knots, he explained, “some say ‘speed, correcting’ or just ‘speed.’ We encourage people to signature it. What is non-negotiable is to say it, every time. If you don’t condition yourself to discipline an action, it’ll drift on you. It’s the priming of the psychological pump, that’s the warnings.”
The goal for Safe to Land is to consistently use three new stable approach gates, at 1,000, 500, and 200 feet. The pilot needs to check for stable approach criteria at each gate and verbalize the status. For example, say “configured” at 1,000 feet, “stable” when properly aligned at 500 feet, and then “continue” or “limit, go-around” at 200 feet. If there is an instability at one of the gates, the pilot should keep repeating it until it is corrected. For example: “airspeed, airspeed…”
At the 200-foot limit, Smith advises saying “continue” instead of “landing” because “there is a difference between ‘continue’ and ‘landing,’ he said. “[Some] 52 percent of excursions follow a stable approach. It’s not a good idea to say ‘landing’ because that puts the pilot into a mental state of expecting the approach to end in a landing, and as we learned during the simulator demonstration, a lot can happen after the 200-foot mark.”
At 200 feet, the airplane is stabilized if airspeed is Vref -5/+10 knots, bank is a maximum of 15 degrees, alignment is within the runway edge lines, and it’s on glide path. “Anytime the flight becomes unstable below 200 feet, the opportunity to re-stabilize the flight has passed, and a go-around must be executed,” according to CJP.
Centerline and Touchdown Point Limits
Misalignment with the runway centerline can easily happen at the last minute, and the Safe To Land initiative will help pilots learn how to determine “how far it is safe to drift away from the runway centerline” so they know that they have exceeded the drift limit and must go around. Basically, this involves defining a drift limit for the airplane where the runway centerline intersects the corner of the glareshield.
The longitudinal limit requires a little more consideration and results in a touchdown point limit (TPL) “after which a go-around must be initiated.”
There are two elements to think about for longitudinal considerations.
First is the green touchdown zone (GTZ), which is the touchdown target. Pilots are taught to touch down on the aiming point at the 1,000-foot distance markers, but the GTZ acknowledges reality and gives pilots a larger 1,000-foot “bulls-eye” from the 500-foot distance markers to the 1,500-foot distance markers.
Next is the TPL, which must be calculated for each runway. Once the airplane reaches the end of the GTZ bullseye, the pilot needs to clearly verbalize that fact, by saying the word “floating” every one to two seconds until either touching down or if still in the air when the airplane reaches the TPL, then going around.
To calculate the TPL, start by subtracting factored landing distance (FLD) from landing distance available (LDA). The result is called the “extra distance,” and this is added to the air distance from the runway threshold to where the wheels touch down. The result gives the pilot a solid limit beyond which a go-around is mandatory, otherwise, the airplane will not be able to stop by the end of the runway.
Here is an example for Montgomery-Gibbs Executive Airport (KMYF) in San Diego. Landing on Runway 28R initially looks promising because of the runway’s 4,598-foot length. But it has a displaced threshold of 1,199 feet, essentially making it a 3,399-foot runway, which may be marginal for a CitationJet.
FLD for a typical CitationJet is 2,465 feet under certain conditions. Subtracting that from the 3,339-foot LDA gives 934 feet, the extra distance. Add 934 to the air distance, say 1,300 feet, gives a result of 2,234 feet, which is the TPL.
Looking at the airport chart for KMYF shows that the TPL is 1,165 feet from the 10L end of the runway, which means that if you’re landing on 28R, you must touch down before hitting the 10L aiming point markers, which are 150 feet long.
Thinking about this and making the TPL calculation ahead of time provides a clear limit for determining whether to go around from a floater landing. But it’s also helpful, CJP pointed out, to look at the airport chart after calculating the TPL to find a geographic reference, such as the aiming point markers mentioned above.
For the simulator trials using KHTO, it turned out that a crossing runway matched the TPL, giving a clear geographic reference.
Flying the Profiles
FlightSafety and CJP welcomed a group of journalists to try out the simulator profiles. I joined Flying columnist Dick Karl and AOPA Pilot editor-in-chief Tom Haines in the M2 simulator in Wichita. Our instructor was FlightSafety’s Dax Beal, and Martin Smith was there to observe and hand over the top-secret codes for inputting our deviations into the simulator.
We started each profile on final to KHTO’s Runway 28, with the GPS Y RNAV approach programmed in the M2’s Garmin G3000 avionics. Vapp was 101 knots and Vref 94 knots. We were briefed to hand fly when Beal unfroze the simulator then it was up to us whether or not to engage the autopilot for the approach.
Before starting to fly the profiles, each of us got to fly one normal landing, then flew an approach and paused at 200 feet so we could see what one dot of lateral deviation on the localizer looked like close to the ground. After landing from this approach, we taxied on either side of the runway centerline to assess the sight picture for the lateral limits.
Both Karl and Haines handled the injected perturbations well, using the CJP-derived callouts and making decisions at the limit points that either led to a correction and a safe landing or a safe go-around. Some approaches were purely visual, while others were in IMC but breaking out with plenty of ceiling and visibility.
One example was an approach where everything was fine almost to 200 feet, but then the speed ballooned by about 30 knots, and Haines wisely chose to go around instead of trying to salvage the landing. From the back of the simulator, Smith commented, “That was well-managed. It was not recoverable.” He praised Haines for “priming his psychological pump” by making the calls. Karl likewise made the right decisions after Beal input some instabilities, going around after a one-dot deviation on the glidepath and again after sliding sideways (and making the “drifting, drifting…” callout) at 200 feet.
During my time in the left seat, I got a combination of issues and tried to focus on the callouts and the limits. Having watched Haines and Karl first, I had a good idea of what to look for, but it was still surprising to be all lined up and ready to ease down the last 200 feet and suddenly see the runway sliding away to the side. In this case, I started to bank back to the runway but quickly saw that I’d have to steepen the bank past 15 degrees so leveled the wings and did a go-around.
The TPL demo was most instructive. On Runway 28 at KHTO, the second (closed) crossing runway marks the limit so it was easy to see as the M2 floated and floated, refusing to touch down. Without having a clear TPL for my decision to go around, I’m not sure I wouldn’t have tried to force the airplane onto the runway, hoping it would stop in time. But knowing that this was a limit made the decision to go around super easy; it was a brain-reliever, simplifying my decision-making and making the whole operation that much safer.
The stable approach gates and limits developed for the Safe to Land initiative are logical, simple, and consistent. More importantly, they are rooted in reality and don’t try to force pilots into doing a go-around when it isn’t truly necessary.