1.1 HISTORY OF FLIGHT Use your browsers 'back' function to return to synopsisReturn to Query Page
On April 6, 2005, at 1300 Hawaiian standard time, a Schweizer SGS 2-32 glider, N693U, impacted mountainous terrain 0.4 miles south of the Dillingham Airfield, Mokuleia, Hawaii. The commercial glider pilot was fatally injured and the two passengers sustained minor injuries. The glider sustained substantial damaged. Sailplane Ride Adventures, Inc., owned and operated the glider under the provisions of 14 CFR Part 91 as a scenic sailplane ride. Visual meteorological conditions prevailed, and a flight plan had not been filed for the local flight. The 20-minute commercial scenic flight was in the air approximately 17 minutes.
1.1.1 Passenger and Witness Statements
According to an interview summary provided by the Federal Aviation Administration (FAA), the passengers reported that they were circling around a hill and thought that they were returning to the airport. The glider crossed over a ridge to a valley to look at a waterfall. The glider turned left then right in a gentle but accelerating manner. The glider also pitched up and down, and the passengers felt like they were falling. The pilot announced that they were "going in." The glider impacted trees and terrain, and came to rest upside down.
A witness, who had 7,000 hours of glider experience and was flying at the time of the accident, observed the accident glider behind her, heading east approximately 400 to 500 feet above the ridge. She checked back on the glider's position relative to hers and noticed the glider "turn right (toward the ridge) and its nose come up slightly." The glider turned "approximately 45 degrees to the right, then turned back to the left and immediately entered a spin to the left." The witness reported that the glider rotated twice before it entered a spin to the right. The witness then lost sight of the glider behind trees before it completed a rotation to the right.
1.1.2 Onboard Video and Audio Recording System
The glider was equipped with a custom designed and installed video and audio recording system intended to provide customers with a video record of their tour flight. The videotape was retrieved from the accident glider and sent to the National Transportation Safety Board Vehicle Recorders Division located in Washington, D.C. A Vehicle Recorders Division engineer provided a factual summary and partial transcripts gleaned from the onboard video recording. The VHS tape was recorded by an on-board video/audio recording system that would normally provide two camera views; one inside the glider looking rearward at the passenger(s) in the rear seat, and another camera in the tail of the glider with a view looking forward. Both cameras could be recorded at the same time, with one set as the "main view" that would fill the viewing screen, and the other as a smaller inset overlaid on top of the main view, in the upper left portion of the viewing screen, in a "picture-in-picture" type of configuration. Two individual video frames (about 0.06 seconds), located at the beginning of the recording, show the "main view" from the internal camera and the smaller inset view from the external tail camera. However, for the remainder of the recording the view from the tail camera was not recorded. Both the main full screen view and the small inset area contained the same video, from the interior passenger view camera. The VHS tape contained about 20 minutes 12 seconds of recorded data
While primarily an internal view of the glider, small portions of the side and overhead canopy were visible, along with a waist up view of the passengers. The pilot was generally not visible, though occasionally his left arm/shoulder, neck, and left side of his face were visible. No controls or instruments could be seen in the recording. Audio was recorded consisting of communication between the pilot and the passengers, describing the landmarks and sights on the tour. Some relative motion can be seen in the clouds above and behind the glider, and at times, some ground features can be seen in the background. There were no audio or visual cues that indicated any problems with the glider or its operation, the weather, or any other concerns, until about 1 second before the end of the recording. While the location and altitude of the glider at the time of the end recording could not be determined from the video, it appeared that the recording ended prior to impact, and after the airplane had been rolling toward the left (the roll attitude could not be determined, only the trend in roll as indicated by the clouds in the background).
A partial transcript of the conversation between the pilot and passengers was generated by the Safety Board Vehicle Recorders Division. The transcript was limited to statements or observations that may provide information about the location or operation of the glider, other traffic, weather conditions, and conversations about the pilot's experience. Review of the transcripts revealed that the male passenger asked, "with these wind currents you guys can stay up for, hours?" The pilot answered, " Yup. Today not so much cause it's mostly ah east wind...but when it's a northeast wind we can stay up for as long as we want." Later the male passenger asked if, "the weather was good would you go further south and north...?" The pilot responded, "...if lift was a little better, I'd go you know, further west and further east but...lift just isn't doin well for us so that's our main concern since we don't have any other ways...of makin it back to the airport. And when the lift is good and we're at about 3,500 feet, I'll go way into the Great Valley way over there and cruise around, have some fun over there, but, its just not enough today." The pilot then mentioned a waterfall and conducted a steep turn. Following the steep turn, he began to report on some of the local highlights. The male passenger then asked, "So how long did it take you to get your license...six months?" The pilot answered, "Uh I think it was close to that...but I was flyin everyday, so..." Near the end of the recording the pilot began to point out a 200-foot waterfall to the passengers and said he would make a slight turn so they could see it (clouds/horizon in background indicate a roll to the right). He pointed it out and said it was tough to see and began a roll back toward the left. About 8 seconds later the pilot said, "Whoa, we're in some sink here," which was the last recorded communication.
2.1 PERSONNEL INFORMATION
2.1.1 Pilot Information
The pilot began his glider flight training in January 2005, and received his student pilot certificate on February 18, 2005. On March 16, 2005, the pilot failed his first attempt to obtain his private pilot certificate with a glider rating (in the areas of weather information, operation of systems, visual signals, airport, national airspace, and runway and taxiway signs, markings and lighting), but on March 24, 2005, he successfully passed the private pilot check ride with a FAA Designated Examiner (DE). On March 26, 2005, he obtained his commercial pilot certificate with a glider rating from the same DE that gave him his private pilot certificate 2 days prior. According to the pilot's logbook, as of April 5, 2005 (the day before the accident), he accumulated a total of 48.4 hours of flight time, of which 31.2 hours were as pilot-in-command and 7.1 hours were accumulated in the accident glider make and model. The logbook entries indicated that the pilot provided 7.8 hours of scenic tour flights prior to the accident. Review of the pilot's logbook revealed that he began providing scenic flights to the public on the day of his commercial check ride.
2.1.2 Pilot Training
Review of the pilot's Glider Flight & Ground Training Syllabus for the student, private, and commercial course revealed he obtained ground and flight training in spins and spin recovery (left and right spins, spins from a steep turn, uncoordinated over-the-top spins, and secondary stall-spins) on the same day (February 19, 2005) that he received training in the following subject areas:
Knowledge and Practical Training:
Simulated Off-Field Landings
Aircraft Weight and Balance
Cross-Country Flight Profiles
Dillingham Field Checkout
Recovery From Bad Bounce Procedures
Simulated Off Field Landing Procedures
Landing - Crab for Cross Wind
Spot Landing - Spoilers Open and Closed
Traffic Patterns with All Instruments Covered
Glide Slope Angles - No Altimeter Used
Unusual Attitudes Recognize & Recovery
Wings Level Full Rudder Stall with/without Spoilers
Proper Clearing Turns
Transition Up & Down Through Wake
Slack Creation in a Turn with Recovery
Box the Wake Procedures
Steering the Tow Plane
Rope Break Procedures 100 feet
Rope Break Procedures 500 feet
Full Traffic Pattern - Landing Alternatives
Emergency Procedures - Can't Release
Down Draft Recognize and Recovery
Simulation Spoilers Stuck Open
Simulation Spoilers Stuck Closed
Emergency Procedures Too Low on Final
Low Pattern Entry (Emergency Procedures)
Emergency Procedures Land on Tow
Rope Break 300 feet (180-degree Turn Downwind)
Actual Tow-Plane Wave-Off
Downwind Landing (below 10 knots)
Simulated Off-Field Landing
Determine Safe Altitude
Final Approach Pitch Down After Opening Spoilers
Slips vs. Skids
Slips to a Spot Landing
Turning Slip Procedures
Side Slip Procedures
Spiral Dive Entry Recovery/Prevention
Turning Stalls - Spoilers Open/Closed
The Use of and Calculation of Thermal Index
Air Traffic Control (ATC) Clearance Lights
Wave Soaring Techniques
Convergence Lift Techniques
Determine Wind Direction From Field Circle
Base Turn Call Out - Too High/Low or OK
Landing - Wings Level Side Step Maneuver
Cloud Clearance & Visibility Requirements
Tow Plane Pilot Requirements
Review of the pilot's logbook revealed he flew his first solo flight on February 19, 2005, and continued flying solo flights until March 15, 2005, when he began receiving training in preparation for the private pilot check ride. When asked to review the accident pilot's pre-solo written exam, the operator reported that he could not find the exam and indicated that he remembered the pilot "did very well." When asked if he knew why the accident pilot failed his private pilot certificate, the operator indicated that he failed the knowledge portion of the exam and the examiner didn't fly with the pilot. The operator added that after the failure, he asked the pilot what he had been studying. The pilot presented the operator with the training books used for the certified flight instructor (CFI) course, specifically the CFI oral test guide. The operator added that the pilot never received the private pilot test guide.
The pilot logged 1.3 hours of spin training, which was received in the accident glider make and model. According to the operator, the pilot received spin training from three instructors; his usual instructor, the operator, and another instructor. The operator indicated that he required all commercial students to obtain spin training in the accident glider (Schweizer SGS 2-32) and the accident pilot had received emergency procedure and spin training from the operator. He added that he conducted two flights with the accident pilot where they climbed to 5,000 feet to conduct spin training. He said on one occasion the accident pilot didn't get the stick forward enough on a spin recovery and got into a secondary stall. He then had the accident pilot demonstrate two more successfully. The operator reported overseeing the pilot's training in spins that included steep turn spin entries and recoveries, cross-control spins, over-the-top spin entries and recoveries. After the accident pilot demonstrated these, the operator indicated he was "Good to go and give rides."
The operator informed investigators that he told the pilot not to go back so far on the ridge due to the possibility of severe downdrafts. He also indicated that their standard operating procedure was to stay at least 2,500 to 3,000 feet mean sea level (msl) while flying over the ridge where the accident was located. He expressed the importance of not going toward the south side of the ridgeline, which was subject to downdrafts. The operator also reported that he emphasized this because in 1995, they had a SGS 2-33 glider experience a similar situation and crash in the same area (Safety Board accident number LAX95LA184).
According to the operator, the accident pilot received about 3 or 4 rides a day in preparation for his commercial certificate.
3.1 AIRCRAFT INFORMATION
3.1.1 Glider Information
The glider was issued a standard airworthiness certificate in June 1965, and underwent its last 100-hour inspection on January 10, 2005, at an aircraft total time of 5,692 hours, and its last annual inspection on March 29, 2004, at a total time of 5,310.0 hours. The total time of the glider at the time of the accident is unknown.
The glider was 26.75 feet in length, with a wingspan of 57 feet, a wing area of 180 square feet, and an aspect ratio of 18.05. The glider was equipped with ailerons and a dive brake mechanism (similar to a spoiler). The published stall speeds for the glider ranged between 41 and 47 miles per hour (mph) with associated weights ranging between 1,020 to 1,430 pounds.
According to the flight manual, under general description, the glider was "ideal for transition training from low or intermediate to high performance, single place sailplanes." The flight manual also indicated that, "spin entries are normal throughout the C.G. [center of gravity] range. After the entry, there will probably be one nose up and down oscillation before the stable spin occurs. The rotations are relatively slow with an altitude loss of approximately 300 feet per turn. Recovery technique is normal, except that considerably more control is needed to stop the rotation and lower the nose. Instead of easing off back pressure on the stick, it must be pushed forward of neutral and instead of neutralizing the rudder, opposite rudder must be applied. The rotation can be stopped in 1/4 to 1/2 turn. Pull outs, depending on the loading of the sailplane, can be made at airspeeds of 75 - 90 mph without appreciable G-loads."
The rear seat control stick was removed prior to the accident flight, but the rudder pedals and spoiler handle were kept in place. Neither was guarded.
3.1.2 Weight and Balance Information
According to the glider's flight manual, it had an approved maximum gross weight of 1,430 pounds for a utility class glider and an approved maximum gross weight of 1,340 pounds for a high-performance glider. Utilizing the accident glider's last weight and balance information (dated January 4, 2002), the pilot and passenger weights (147, 195, and 133 pounds), and a 24-pound ballast beneath the pilot's seat, investigators determined that the maximum gross weight was exceeded by about 34 pounds, but the center of gravity (cg) was determined to be 17.38 inches aft of the datum, within the 15.2 to 19.3 range.
4.1 METEOROLOGICAL INFORMATION
The weather observation facility located at the Wheeler Army Airfield (HHI), 10 nautical miles southeast of the accident site, reported the following meteorological information at 1255: wind from 090 degrees at 2 knots; visibility 7 statute miles in light rain showers; a few clouds at 1,500 feet above ground level (agl) and broken clouds at 3,000 feet agl; temperature and dew point of 21 degrees Celsius; and an altimeter setting of 30.15 inches of mercury.
The weather observation facility at the Honolulu International Airport (HNL), 22 nautical miles southeast of the accident site, reported the following meteorological information at 1253: wind from 060 degrees at 19 knots with gusts to 24 knots; visibility of 10 statute miles; a few clouds at 2,800 feet agl and scattered clouds at 5,500 feet agl; temperature 27 degrees Celsius; dew point 18 degrees Celsius; and an altimeter setting of 30.10 inches of mercury.
The witness who observed the accident indicated that normally in the Dillingham area, the trade winds come in from shore and hit the mountain ridge running east-west along the northwest side of Oahu. The winds are then deflected up providing a great deal of lifting energy. On the day of the accident, however, the winds were shifty and gusting and they did not produce the updraft along the ridgeline that is most common in that area. In addition, the cloud bases would not allow for a tow greater than 2,000 feet.
First responders to the accident site reported to the U.S. Coast Guard that they were experiencing heavy downdrafts in the area of the accident site and could not lift the pilot and passengers out of the accident area with their helicopter assets. Subsequently, the U.S. Coast Guard HH-65 air lifted the pilot out of the accident site area and reported experiencing strong turbulence and downdrafts.
5.1 WRECKAGE AND IMPACT INFORMATION
The accident site was at 21 degrees 34 minutes 21 seconds north latitude and 158 degrees 12 minutes and 54 seconds west longitude at an elevation of approximately 1,000 feet msl. The glider came to rest on the east side of a gulch that cut through the east-west running ridgeline situated to the south of Dillingham Airfield. The gulch where the wreckage came to rest was an area commonly referred to as the "toilet bowl" by local glider pilots. The reason for the "toilet bowl" label was the rotating downdrafts commonly found in the area.
Review of photographs of the accident site revealed that the glider fuselage came to rest inverted with the left and right inboard wings intact. The left and right outboard wing sections were detached; however, the left outboard wing section remained attached to the main wreckage via flight control cables. The right outboard wing section came to rest approximately 40 feet from the main wreckage at the base of freshly broken trees. The wing leading edges displayed circular indentations similar in size to the diameter of the surrounding trees. The tail section folded over the belly of the airplane.
The glider was recovered to Dillingham Airfield on April 8, 2005. According to the FAA inspectors that responded to the accident site, flight control continuity was confirmed from the cockpit to the flight control surfaces. The Safety Board investigator-in-charge (IIC) examined the wreckage on April 12, 2005, at the Dillingham Airfield. The pilot's seating area (front seat) sustained the most impact damage with the cockpit area being deformed up, aft and to the right. The canopy was destroyed.
6.1 MEDICAL AND PATHOLOGICAL INFORMATION
The Civil Aeromedical Institute, Oklahoma City, Oklahoma, performed a toxicological test for carbon monoxide, cyanide, volatiles, and drugs, with negative results. A clinical report was attached to the toxicological test results indicating that the pilot had 120 mg/dL of glucose detected in the pilot's urine and 4.4 percent hemoglobin A1C detected in blood. According to the clinical report, "postmortem vitreous glucose levels above 125 mg/dL are considered abnormal and postmortem urine levels above 100 mg/dL are considered abnormal. Hemoglobin A1C blood levels above 6 percent are considered abnormal." "Elevated postmortem vitreous glucose levels are considered hyperglycemic conditions, which may or may not have been a factor in the accident. An abnormally high postmortem vitreous glucose level could have been caused by diabetes mellitus or several other medical conditions. Elevated glucose levels can also be caused by emergency medical treatment, strenuous exercise, strong emotions, shock, and burns. Elevated postmortem urine glucose levels could be caused by diabetes mellitus or several other medical conditions, which may or many not have been a factor in the accident. It is impossible at the present time to identify hypoglycemic conditions in postmortem specimens. Glucose levels in postmortem samples drop rapidly and frequently drop to zero."
Glider pilots are not required to obtain a medical certificate for personal or commercial operations. However, no pre-existing medical anomalies were reported to the Safety Board investigator-in-charge.
An autopsy on the pilot was conducted by the Department of the Medical Examiner for the City and County of Honolulu. According to the autopsy report, the medical examiner determined that the pilot died as a result of an intracranial injury sustained in the accident.
7.1 SURVIVAL FACTORS
The glider came to rest with the topside of the glider touching terrain. The front and the rear seats (more of a cupped bench seat) were equipped with four-point restraint systems. Behind the rear seat passengers was the area where the inboard main wing pins connect, which provided an extra elevated area of support (resembling, but not intended as a roll bar) for the weight of the inverted glider. Directly aft of the pilot seat was a horizontal bar that joined the left and right side of the cockpit, parallel to the glider's lateral axis. The bar was the support for the pilot's shoulder harness, but was not positioned higher than the pilot's shoulders.
8.1 ADDITIONAL INFORMATION
8.1.1 Federal Aviation Regulations Relating to Glider Pilots
Review of the Federal Aviation Regulations (FARs) revealed that 14 CFR Part 61 subpart E - Private Pilots, indicates that under Part 61.105 aeronautical knowledge, the private pilot should, among other things, receive training from an authorized instructor in various areas including the aeronautical Information manual and FAA advisory circulars, recognition of critical weather situations from the ground and in flight, wind shear avoidance, and the procurement and use of aeronautical weather reports and forecasts, principles of aerodynamics and aircraft systems, stall awareness, spin entry, spins, and spin recovery techniques for the airplane and glider category ratings.
The flight proficiency requirements specified in Part 61.107 indicated that a person applying for a private pilot certificate with a glider rating must receive and log ground and flight training from an authorized instructor on areas such as preflight preparation, preflight procedures, airport and gliderport operations, launches and landings, performance speeds, soaring techniques, performance maneuvers, navigation, slow flight and stalls, emergency operations, and post-flight procedures.
The aeronautical experience of Part 61.109 indicated that an applicant for a private pilot must log at least 10 hours of flight time in a glider that includes at least 20 flights in a glider in the areas of operations listed in 61.107 including at least three training flights in a glider with an authorized instructor in preparation for the practical test that must have been performed within the 60-day period preceding the date of the test. Part 61.109 also requires 2 hours of solo flight time in a glider with not less than 10 launches and landings.
Title 14 CFR Part 61 subpart F - Commercial Pilots, indicates that a candidate for a commercial pilot certificate with a glider rating shall obtain flight proficiency in the same areas listed under 61.107 for the private pilot certificate. The aeronautical experience required for a glider rating under a commercial pilot certificate is set at a minimum of 25 hours of flight time including at least 100 flights in a glider as pilot-in-command. In order to take the commercial practical test, the pilot must undergo 3 hours of flight training in a glider or 10 training flights in a glider with an authorized instructor, including at least 3 hours of training within 60 days prior to the practical test. In addition, the pilot is to obtain 2 hours of solo flight that include not less than 10 solo flights in a glider.
8.1.2 Practical Test Standards for Glider Pilots
The practical test standards (PTS FAA-S-8081-23) for the commercial pilot certificate indicates that a flight instructor's responsibility is to train the commercial pilot applicant "to acceptable standards in all subject matter areas, procedures, and maneuvers included in the TASKS within each AREA OF OPERATION in this practical test standard. Because of the impact of their teaching activities in developing safe and proficient pilots, flight instructors should exhibit a high level of knowledge, skill, and the ability to impart that knowledge and skill to students."
The PTS for the commercial pilot certificate indicates that the following tasks must be demonstrated during the practical test:
TASK: RIDGE AND SLOPE SOARING
REFERENCE: Soaring Flight Manual.
Objective. To determine that the applicant:
1. Exhibits knowledge of the elements related to ridge and slope soaring.
2. Recognizes terrain features and wind conditions which create orographic lift.
3. Enters the area of lift properly.
4. Estimates height and maintains a safe distance from the terrain.
5. Exhibits smooth, coordinated control, and planning to remain within the area of lift.
6. Uses correct technique to re-enter the area of lift, if lift is lost.
7. Remains oriented to ground references, wind, and other aircraft.
8. Uses proper procedures and techniques when crossing ridges.
9. Maintains proper airspeeds.
TASK: MANEUVERING AT MINIMUM CONTROL AIRSPEED
REFERENCES: Soaring Flight Manual, Glider Flight Manual.
Objective. To determine that the applicant:
1. Exhibits knowledge of the elements related to maneuvering at minimum control airspeed, including flight characteristics and controllability.
2. Establishes and maintains the airspeed at which any further increase in angle of attack or change in configurations would result in a stall in straight or turning flight in various configurations and bank angles.
3. Adjusts the airspeed to avoid stalls in turbulent air or as bank is increased.
4. Applies control inputs in a smooth and coordinated manner.
5. Uses proper procedures to avoid stalls when raising a lowered wing.
6. Maintains heading, ±10°, during straight flight, and the desired bank angle, ±5°, during turns.
TASK: STALL RECOGNITION AND RECOVERY
REFERENCES: Soaring Flight Manual, Glider Flight Manual.
Objective. To determine that the applicant:
1. Exhibits knowledge of the elements related to stall recognition and recovery, including the aerodynamic factors and flight situations that may result in stalls, and the hazards of stalling during uncoordinated flight.
2. Selects an entry altitude that will allow the maneuver to be completed no lower than 1,500 feet AGL.
3. Establishes and maintains a pitch attitude that will result in a stall during both straight and turning flight with and without flaps, spoilers, or dive brakes, as appropriate.
4. Maintains a bank angle of 15°/±5°, during turns.
5. Recovers promptly at the first indication of buffeting or rapid decay of control effectiveness.
6. Uses smooth and coordinated control applications throughout the maneuver.
8.1.3 Dillingham Glider Operations
The Dillingham Airfield has extensive glider operations in the airport vicinity on a daily basis. At the time of the accident, there were two glider operators based at the airfield.
Both operators advertised as providing scenic rides over the Dillingham area with fares varying with the length of the flight. Dillingham Airfield provides a unique opportunity for tourists visiting Oahu to take scenic rides with a 14 CFR Part 91 operator while charging a fare. As a result, the operators are not required to have minimum training requirements or regularly scheduled oversight and surveillance from the FAA. If they establish minimum training criteria for the pilots providing rides to fare-paying passengers, they do so on their own accord.
When asked, the owner of the accident operator believed the accident could have been prevented through increasing the minimum flight and flight hours for the commercial pilot certificate. However, the operator did not establish his own minimum hours or experience requirements for their training operations.
8.1.4 Soaring Society of America and the Soaring Safety Foundation
Shortly after the accident, the Safety Board IIC contacted the Soaring Society of America (SSA) and the Soaring Safety Foundation (SSF) to discuss the FAA's minimum flight requirements for the commercial glider certificate. According to SSA and SSF personnel, pilots do not usually obtain their commercial pilot certificate in such a short period of time and that it usually takes about 6 months to a year to obtain the flight training required to take the knowledge and practical tests for the commercial pilot certificate. SSA and SSF personnel opined that 3 months could be too short to obtain the broad experience required to handle various weather and flight conditions. The SSA and SSF personnel did not have exact numbers regarding the number of glider pilots in the U.S., but they indicated that transition ratings are more common, where pilots already rated in single engine airplanes, obtain a glider rating as an add-on. Those pilots have the minimum flight time required for the private pilot certificate with a single engine airplane rating, which equates to a minimum of 40 flight hours. Considering the fact that commercial pilots could take fare-paying passengers for a ride and be compensated, the SSA and SSF personnel were asked whether or not the minimum flight time and flights required for the commercial certificate with a glider rating should be increased, the personnel indicated that they believed the responsibility should instead fall on the instructor who was endorsing the student for the commercial certificate to ensure that the student has obtained the experience and training required to safely conduct a commercial flight.