Could you do it?

Bizjets, up to and including the airliners configured as bizjets, have published standard day landing and stopping distances under 3,000 feet. Many are less than 2,500 feet. Think you could wedge a Boeing 737 Max 8 into a 2,500-foot-long runway? Or even a Cessna Citation M2 into that same strip of short pavement? The published data says you can.

Those distances include approach at typical landing weight (i.e., landing with an average payload of passengers and reserve fuel for diversion to an alternate), crossing the runway threshold at 50 feet, and coming to a complete stop without using engine reverse if it is installed.

I don’t doubt the accuracy of these distances or the test pilots who collected the data for the FAA-approved manual. But what I do know is that these test landings were not conducted to 2,500-foot-long runways, and that the numbers apply to specific conditions that are not the norm of everyday flying.

FAR Part 25 describes how landing performance data is measured for “large” airplanes that have a maximum takeoff weight above 12,500 pounds. Most light business jets were certified under the commuter category of FAR Part 23 (now standard category following a rule change in 2016) but abide by the Part 25 rules for runway performance data collection.

Under Part 25, test landing must be flown with a stable standard approach angle at an airspeed no lower than VREF to cross the runway threshold at 50 feet. The rules say the vertical velocity—sink rate—cannot be excessive and the airplane can’t tend to bounce or swerve upon touchdown. In other words, no floating looking for a smooth touchdown and only enough flare to keep from hitting nosewheel first.

Maximum braking is allowed, as is immediate deployment of stopping aids such as ground spoilers or lift dump systems. And no extraordinary pilot skill can be required. I know I can sure make a “firm” landing without extra skill, but even my biggest thumps are not as “firm” as the experimental test pilots use.

Of course, the test approaches are flown to long runways and are repeated until the test pilots nail every parameter. The rules don’t require the test pilots to make every approach perfectly, but they must be able to repeat the results with reasonable regularity.

I doubt you’ve been part of a maximum effort landing that the rules define because it’s not something we want to put our passengers or our airplane through. Words like “violent,” or at least “uncomfortable” come to mind when you bang it on the runway and jam on the brakes and feel the anti-skid cycling like crazy. The deceleration can be so abrupt that unmoored objects in the cabin come flying forward. Your passengers would demand an explanation for such an experience.

Of course, those radically short landing distances that I mention only apply at a sea level airport on a 15 degree C day with a dry runway and no gusting wind. Every variable such as higher airport elevation and air temperature will alter landing distance. So will gusting winds and any contamination on the pavement, or residual ice on the airframe. Those adjustments to the required landing runway—called factors—can be found in the AFM (airplane flight manual) and can also be calculated by some flight management systems.

Still, the “factored” landing distance doesn’t contain any significant margin for imperfect pilot technique or other variables. Only a few feet of float past the touchdown aim point can add hundreds of feet to the required stopping distance. Floating can be caused by too fast an approach airspeed, but also by simply holding the airplane off feeling for a smooth touchdown. After all, VREF includes about a 30 percent margin above stalling speed so you can float for considerable distance before the airplane will stall and fall to the pavement even when the approach speed was exactly on target.

Regulators know that the certification criteria includes no landing distance margin so they build margin into the operating rules. If you fly for hire under Part 135 the AFM landing distance can’t be more than 60 percent of the actual runway length. If the runway is contaminated by water or snow or slush the Part 135 landing distances can become limiting for many GA airports.

Those of us who fly under FAR 91 for business or for our own other reasons have no regulatory requirement to build in runway landing length margins. And, not surprisingly, runway overshoots or runway departures are the leading cause of GA turbine airplane accidents. We can fly our bizjets by the book and still end up bending the airplane on a short runway.

Some more recently certified bizjets include the approach and landing factors in the AFM landing distance making them part of the required runway calculation. Many other jets with certification roots tracing back years ago provide the factors only as advisory data. In other words, you’re warned about how much more runway may be needed under each actual approach condition, but it’s up to you to apply those factors to your planning.

What landing runway margin makes sense for we Part 91 operators? Certainly applying the flight manual advisory factors for runway contamination, wind and icing is a place to start. The FAR 135 60 percent rule has been around a long time and we could voluntarily use the same standard but that much margin can limit use of many convenient GA airports even under normal conditions. And the 60 percent rule can really shut down your operations to wet runways or in other situations where you have imperfect information of the actual runway conditions.

It would be conservative to declare we won’t yield any safety edge to the charter operators and apply the 60 percent rule for every approach and landing. But that negates a big reason we fly our own airplanes for our own reasons. FAR 91 demands we make our own decisions to balance arbitrary margins against the utility and efficiency of using the airports that best suit our own mission.

I’m not willing to give any pilot exact advice on how to set a landing distance margin for their bizjet flying, but I would advise all of us to consider exactly how those AFM distances were determined. If you’re not ready and able to apply those abnormal conditions the test pilots used, add some feet to the runway length you’ll accept. The older you get, the more hours behind you, the more feet I believe you will be tacking on.

J. Mac McClellan is a corporate pilot with more than 12,000 hours, and a retired aviation magazine editor living in Grand Haven, Michigan.