July 1, 1992
Who among us hasn't had the misfortune of a hard landing? Answer: probably none. We've all made the kinds of mistakes that lead up to a hard landing and, more often than we'd like to admit, keep on making them. While hard landings may be the subject of pilot humor, they occur frequently enough to indicate a rather serious trend in accident statistics. Hard landings account for a significant number of accidents in the landing phase. And while they don't usually cause injuries or death, they do cause a substantial amount of airframe damage.
Hard landings are very tangible, and memorable, reminders of deficiencies in pilot technique. For low-time pilots, hard landings usually are the product of inexperience and some very common errors in judgment.
One is flaring too high or too soon in the landing sequence. Sometimes, the early flare is associated with a pilot's fixing his gaze on an area too close to the airplane during the landing. By fixating on a spot too close to the front of the airplane, useful flaring cues can't be perceived. For one, there can be an impression that the airplane is closer to the runway than it really is. Another problem with a close-in focus is that the airplane's attitude can't be properly judged. Without a wide-angle view of the entire surroundings, the pilot cannot determine whether the airplane is in the proper landing attitude — that is, nose high, with wings at the proper bank angle or crabbed for any crosswind correction that may be necessary.
Optimum landing technique requires pilots to look well ahead of the airplane as it crosses the runway threshold. This means looking just ahead of the "speed blur" caused by the runway's rushing past — much like the visual technique used when driving a car at highway speeds.
Of course, the "high flare" can also be a simple matter of misjudging the airplane's height above the runway. Practice and more practice is the cure for this syndrome. The proper flaring height is different for each type of airplane and also varies according to airspeed and gross weight. A heavy twin, for example, will require that the pilot initiate the flare much earlier in the landing sequence than a light single.
Poor airspeed management, wind shear, and iced-up airframes are other major causes of hard landings. Here, the problem is an inadvertent stall, either from a suddenly decreasing headwind (as in a wind shear situation), premature stalls due to disruption of airflow over the wings (ice), or just plain flying too close to stall speed.
In gusty conditions, a good rule of thumb is to add one-half the gust factor to the airplane's normal landing airspeed; if the winds are 10 gusting to 20, add 5 knots to your approach speed.
If airframe icing is suspected, it's very important to carry an excess amount of airspeed until the airplane has touched down. Stall characteristics are severely altered by even the smallest ice accretions, so excess airspeed is vital — in flight as well as on approach. For this reason, some manufacturers give a recommended airspeed for flying in suspected icing conditions; also, some specify no flaps. This assumes, of course, that you've done your very best to avoid icing conditions in the first place and that your encounters are inadvertent. As the record shows, small ice accretions can down the most powerful, well-equipped airplanes.
In addition, many hard landings occur during the course of instructional flights, when students or instructors attempt such maneuvers as accuracy or short-field landings. All the above causes are well-represented in the AOPA Air Safety Foundation's aircraft accident database. Let's look at a few to understand some of the more typical hard-landing scenarios.
On April 30, 1987, a private, multiengine-rated pilot was practicing short-field landings with his instructor at Athens (Georgia)/Ben Epps Airport. On short final, the CFI told the student to slow the airplane — a Cessna 310 — to 76 knots. The student reluctantly complied, and the airplane stalled about 30 feet above the runway. The subsequent hard landing caused structural damage to the wings and fuselage. Neither pilot was injured.
On June 29, 1988, another student and his instructor were practicing short-field landings in a Cessna 172 at Greenville (South Carolina) Donaldson Center Airport. On one approach, a short-field approach over a simulated 50- foot obstacle was attempted. The airplane came over the runway threshold at 40 feet agl, with full flaps, 60 mph, and idle power. A high sink rate resulted. The student flared just before touchdown, but the airplane bounced twice. The CFI told the student to add full power, but the airplane only climbed 10 to 15 feet, at which time the left wing dropped and the airplane crashed on the side of the runway. Neither pilot was injured.
A 1,000-hour private pilot flying a Piper Comanche encountered turbulence on approach to Norwalk (Ohio)-Huron County Airport on November 20, 1983. He said that wind shear caused him to drop 40 feet to the runway surface. At the time of the accident, winds were out of the south at 20 knots, with gusts to 30 knots. None of the airplane's occupants were injured.
On November 16, 1983, a 15,000-hour airline transport pilot descended from VFR-on-top conditions into a cloud deck while receiving vectors for an NDB approach to the Millard, Nebraska, airport. The pilot said that his Piper Turbo Lance was in the clouds for between five and eight minutes. On a half- mile final, the pilot said that the airplane's nose became progressively heavy. A go-around was initiated, but the nose pitched farther down, and the airspeed rose by just 2 knots, from 90 to 92 knots. Subsequently, the airplane touched down hard on the nosewheel, bounced, and struck the runway, collapsing the nosewheel. According to the report, one-eighth inch of ice was discovered on the wing leading edges. The pilot stated after the accident that he thought ice had accumulated on the pitot tube and said that the pitot tube was slow to heat after the accident. He also said that the airplane felt like it was flying at only 75 to 80 knots when it landed hard. The pilot — the sole occupant of the airplane — was uninjured.
An 800-foot ceiling and 2-mile visibility in snow and fog prevailed at the Joliet (Illinois) Park District Airport on March 3, 1984. During an instrument approach in his Cessna 421, the pilot stated that he picked up moderate to severe ice accumulations. He further stated that he saw the ice come off the airplane's wings after he cycled the deice boots. But he said that on short final, at 100 knots, the airplane's control yoke began vibrating. The pilot increased airspeed and lowered the airplane's pitch attitude, but he said he was unable to flare for the landing. A hard landing ensued. Chunks of clear ice were found on the runway, apparently shaken loose by the force of impact. Neither the pilot nor his three passengers was injured.
Perfect landings are elusive, but there's a lot we can do to prevent those damaging firm arrivals. The best preventatives are careful airspeed management, an awareness of dangerously high sink rates on final, and, as always, exercising good judgment throughout the landing procedure. A final thought: Don't hesitate to go around if any approach or flare seems unusual in any way.
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