Emporia, VA, USA
N524SC
CZECH AIRCRAFT WORKS SportCruiser
While landing the Special Light Sport Aircraft at an airport during his first solo cross-country flight, the student pilot encountered a strong wind gust during the downwind to base turn. After turning into the final leg he was "well above the approach path indicator." He then encountered difficulty in “getting the plane on the runway.” During the flare the airplane floated and he applied a “small amount of power,” to keep the airplane from stalling. As the airplane flew above the runway it drifted to the left. After the airplane touched down, the student heard and felt the left main landing gear impact something. Recorded winds at the accident airport were variable at 7 knots. Postaccident examination revealed that the airplane had struck a runway light with its left main landing gear. The airplane's fuselage structure had come into contact with a bell crank during the accident, and a rod end that attached to the bell crank broke. This rendered the pitch control system inoperative. The student pilot stated that he should have "gone around," but he was a "little confused about the airspeed at the time." As a result of this statement, NTSB investigators examined photographic evidence of the airplane's cockpit, and the airspeed information that was published in the airplane manufacturer's Pilot Operating Handbook (POH). The examinations revealed that the airspeed indicator's indicator and airspeed color code range markings did not agree with the information published in the supplied airplane manufacturer's POH and also that the markings were inaccurate. This could lead to confusion as well as an accident, as the indicated airspeed is an important value for the pilot as it directly indicates stall speed and various airframe structurally limited speeds, regardless of density altitude. Furthermore, it was discovered that the stall speed information and airspeed indicator calibration information published in the POH in many cases was inaccurate and contained large differences (in several instances almost 20 knots) between the published indicated airspeeds and the published calibrated airspeeds.
HISTORY OF FLIGHT On December 23, 2008, about 1445 eastern standard time, a Czech Aircraft Works, SportCruiser, N1044Y, was substantially damaged during landing at Emporia-Greensville Regional Airport (EMV), Emporia, Virginia. The student pilot was not injured. Visual meteorological conditions prevailed for the flight, which departed Chesapeake Regional Airport (CPK), Norfolk, Virginia at approximately 1354. No flight plan was filed for the solo cross-country training flight conducted under Title 14 Code of Federal Regulations Part 91. According to the student pilot, he was landing at EMV during his first cross country flight. While in the airport traffic pattern for landing on runway 15, he encountered a “strong wind gust.” during the downwind to base turn. After turning final he was "well above the approach path indicator." He then “encountered difficulty” in “getting the plane on the runway.” During the “flare” the airplane floated. He applied a “small amount of power,” to keep the airplane from stalling, and as the airplane continued to fly above the runway it began to drift to the left. After the airplane “touched down,” the student heard and felt the left main landing gear impact something. AIRCRAFT INFORMATION The accident airplane was a two seat, single - engine, low wing monoplane, equipped with tricycle type landing gear and powered by a 98.6 horsepower, Rotax 912 ULS. It was registered in the Special Light Sport Aircraft (SLSA) category and was supposed to conform to ASTM standard specifications for design and performance of light sport airplanes. According to FAA and maintenance records, the airplane was manufactured in 2007. The airplane’s most recent conditional inspection was completed on December 5, 2008. At the time of the accident, the airplane had accumulated 658 total hours of operation. PERSONNEL INFORMATION According to pilot records, the student pilot did not possess a FAA medical certificate. He reported 21 total hours of flight experience. METEOROLOGICAL INFORMATION A weather observation taken at EMV, about 5 minutes prior to the accident, included; variable winds from 120 degrees to 200 degrees at 7 knots, 10 statute miles visibility, sky clear, temperature 3 degrees C, dew point -11 degree C, and an altimeter setting of 30.63 inches of mercury. AIRPORT INFORMATION According to the Airport Facility Directory, EMV had one runway oriented in a 15/33 configuration. Runway 15 was 5044 feet long and 100 feet wide. Its surface was asphalt in fair condition. The runway markings were non-precision in poor condition and the runway edge markings were badly faded. A 2-light precision approach path indicator was installed on the left side of the runway that provided a 3-degree glide path. WRECKAGE AND IMPACT INFORMATION Examination of runway 15 by a Federal Aviation Administration (FAA) inspector revealed, that a runway light on the left side of the runway had been broken off at its base. The housing displayed impact damage and its lens was broken. Examination of the airplane revealed no preimpact malfunctions of the airplane or engine. The fuselage skin was wrinkled on the left side of the airframe above the wing fuselage juncture and a vertical line of rivets had pulled through the fuselage skin. The main support structure, which the left main landing gear was mounted to, was bent and the surrounding fuselage skin was wrinkled. The left main landing gear had been displaced aft by approximately 3 inches. The nose landing gear assembly had also been displaced and twisted to the left, and the center console and the interior flooring were bent and buckled. The pitch control system was also found to be inoperative. Further examination revealed that the fuselage structure had come into contact with a bell crank, and a rod end from a push pull tube that attached to the bell crank was broken. TESTS AND RESEARCH On January 2, 2009 during a series of post accident interviews, the student pilot's flight instructor advised the NTSB that his student had a "tendency" to be "high on final." He would teach his students to use the precision approach path indicator "as a reference, but not to chase it," and to "be on it or above it." He would rather that they "be high for safety." He would also, "really stress go-arounds." The student pilot also advised the NTSB that he should have "gone around" but he was a "little confused about the airspeed at the time." Precision Approach Path Indicator (PAPI) According to the FAA's Technical Operations Navigation Services Group, The PAPI normally consists of four equi-spaced light units which are color coded to provide a visual indication of an aircraft's position relative to the designated glideslope for the runway. An abbreviated system consisting of two light units can be used for some categories of aircraft operations. PAPI provides guidance down to flare initiation (typically 50 ft). The PAPI is usually located on the left hand side of the runway at right angles to the runway centre line. In good visibility conditions the guidance information can be used at ranges up to five miles by day and night. At night the light bars can be seen at ranges of at least twenty miles. Each light unit consists of one or more light sources, red filters and lenses. Each light unit emits a high intensity beam. The lower segment of the beam is red and the upper part white. Depending on the position of the airplane relative to the specified angle of approach, the lights will appear either red or white to the pilot The pilot will have reached the normal glidepath (usually 3 degrees) when there is an even number of red and white lights. If an aircraft is beneath the glidepath, red lights will outnumber white; if an aircraft is above the glidepath, more white lights are visible. Approach and Landing Guidance According to the FAA's Airplane Flying Handbook (FAA-H-8083-3A), the objective of a good final approach is to descend at an angle and airspeed that will permit the airplane to reach the desired touchdown point at an airspeed which will result in minimum floating just before touchdown; in essence, a semi-stalled condition. To accomplish this, "it is essential that both the descent angle (glide path) and the airspeed be accurately controlled." Since on a normal approach the power setting is not fixed as in a power-off approach, the power and pitch attitude should be adjusted simultaneously as necessary, to control the airspeed, and the descent angle, or to attain the desired altitudes along the approach path. The FAA stated that the roundout and touchdown should be made with the engine idling, and the airplane at "minimum controllable airspeed," so that the airplane will touch down on the main gear at approximately stalling speed. As the airplane settles, the proper landing attitude is attained by application of whatever back-elevator pressure is necessary. Some pilots may try to force or fly the airplane onto the ground without establishing the proper landing attitude. The airplane should never be flown on the runway with excessive speed. It is paradoxical that the way to make an ideal landing is to try to hold the airplane’s wheels a few inches off the ground as long as possible with the elevators. In most cases, when the wheels are within 2 or 3 feet off the ground, the airplane will still be settling too fast for a gentle touchdown; therefore, this descent must be retarded by further back-elevator pressure. Since the airplane is already close to its stalling speed and is settling, this added back-elevator pressure will only slow up the settling instead of stopping it. At the same time, it will result in the airplane touching the ground in the proper landing attitude, and the main wheels touching down first so that little or no weight is on the nosewheel. Furthermore, The FAA also stated that, whenever landing conditions are not satisfactory, a go-around is warranted. There are many factors that can contribute to unsatisfactory landing conditions. Situations such as air traffic control requirements, unexpected appearance of hazards on the runway, overtaking another airplane, wind shear, wake turbulence, mechanical failure and/or an unstabilized approach are all examples of reasons to discontinue a landing approach and make another approach under more favorable conditions. The assumption that an aborted landing is invariably the consequence of a poor approach, which in turn is due to insufficient experience or skill, is a fallacy. The go-around is not strictly an emergency procedure. It is a normal maneuver that may at times be used in an emergency situation. Like any other normal maneuver, the go-around must be practiced and perfected. The flight instructor should emphasize early on, and the student pilot should be made to understand, that the go-around maneuver is an alternative to any approach and/or landing. Airspeed Indicator and Pilots Operating Handbook (POH) According to the FAA, indicated airspeed (IAS) is the airspeed that is read directly from the airspeed indicator on an aircraft, driven by the pitot-static system. It is an important value for the pilot because it directly indicates stall speed and various airframe structurally limited speeds, regardless of density altitude. IAS is also directly related to calibrated airspeed (CAS), which is the IAS corrected for instrument and installation errors. As a result of the students statement that he was a "little confused about the airspeed at the time" NTSB investigators examined photographic evidence of the airplane's cockpit that was provided by the FAA and the airplane manufacturer, and the airspeed information that was published in the airplane manufacturer's POH. Examination of the photographs revealed, that the installed airspeed indicator's markings (miles per hour on the outside arc and knots on the inside arc), and airspeed color code range markings were different, from the airspeed indicator markings (knots only) and airspeed color code range markings shown on the airplane manufacturer's website for their "Standard 6-PAK" installation. Further examination of the photographs also revealed that the installed airspeed indicator color code markings did not agree with the information published in the supplied airplane manufacturer's POH (Revision 1.0) which was published in March of 2006. Moreover, it was also discovered that not only did the color code range markings on the accident airplane not agree with the manufacturer's POH but also that the markings were inaccurate. For example: 1. The bottom of the white arc (stall speed with flaps extended) was approximately 5 knots higher than published. 2. The top of the white arc (maximum flaps extended speed) was 10 knots lower than published. 3. The bottom of the green arc (stalling speed with flaps retracted) was approximately 3 knots higher than published. ASTM Standards and the POH Review of ASTM International's Standard Specification for Design and Performance of a Light Sport Airplane (ASTM Designation: F 2245-07), also revealed that "All flight speeds" were to be "presented" as "calibrated airspeeds." Review of the supplied POH revealed however, that this was not the case, and that the airspeed limitations, and airspeed indicator markings published in the supplied POH, were actually presented as indicated airspeeds. Furthermore, it was discovered that the stall speed information and airspeed indicator calibration information published in the POH in many cases contained large differences (in a couple of instances almost 20 knots) between the published indicated airspeeds and the published calibrated airspeeds. Previous SLSA Airspeed Problems This was not the first time that Safety Board investigators had found Airspeed inconsistencies in SLSA airplanes and documents. Airspeed indicator, airspeed correlation, and POH inconsistencies were also discovered during investigations of a series of in-flight structural breakups of Zodiac CH-601XL airplanes that occurred in the United States between February of 2006 and March of 2009. During those investigations the Safety Board concluded that errors in airspeed correlation data would result in incorrect airspeed data in the pilot operating handbook (POH) and could result in a pilot inadvertently flying at unsafe airspeeds. As a result of the investigation into the in-flight structural breakups, on April 14, 2009, the Safety Board issued recommendations to the FAA to: "Determine the correct airspeed correlation between calibrated airspeed and indicated airspeed for the Zodiac CH-601XL, require that the correct data be included in existing and new airplane pilot operating handbooks (POHs), and ensure that the information on the airspeed indicator is accurate and consistent with the POHs. (Safety Recommendation A-09-36)." "Work with ASTM International to incorporate additional requirements into the standards for light sport airplanes that provide for the accurate determination of airspeed data and for the adequate presentation of that data in existing and new airplane pilot operating handbooks and on airspeed indicators. (Safety Recommendation A-09-37)." ADDITIONAL INFORMATION In order to correct the problems with the SportCruiser's airspeed indicators, and POH inconsistencies, Czech Aircraft Works took the following actions: 1. The pitot-static system on the SportCruiser was modified by inclusion of an AVIATIK WA037383 pitot-static probe in place of the previous design. 2. The airspeed data was recomputed using data from flight testing to establish CAS, which was then compared directly to the IAS in the airplane. 3. The POH was republished with the airspeed data derived from the flight tests and added a caution that "Airspeeds values are valid for standard AVIATIK WA037383 pitot-static probe." Czech Sport Aircraft On April 4, 2009, Czech Sport Aircraft advised that it was now the owner of the design rights for the SportCruiser and would be providing continuing airworthiness support for all of the SportCruisers that were built by Czech Aircraft Works and subsequently by Czech Sport Aircraft. On January 19, 2010, Czech Sport Aircraft advised the SportCruiser was renamed the PiperSport and would now be distributed worldwide by PiperSport Distribution Inc.
The student pilot's failure to maintain directional control during the landing. Contributing to the accident was the improperly marked airspeed indicator and the airplane manufacturer's improper airspeed information.
Source: NTSB Aviation Accident Database
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