Final Report Accident involving a Textron Aviation Inc., Cessna 172K type of aircraft with Registry Number RP-C6923

COA : Certificate of Airworthiness COR : Certificate of Registration CPL : Commercial Pilot License FI : Flight Instructor FIT : Flight Instructor Trainee FSS : Flight Service Station LEIAAI : Leading Edge International Aviation Academy, Inc. LGT : Light MHZ : Megahertz OFSAM : Office of the Flight Surgeon and Aviation Medicine PCG : Philippine Coast Guard PCAR : Philippine Civil Aviation Regulation PCN : Pavement Classification Number RPUS : ICAO designation for San Fernando Community Airport RWY : Runway UTC : Universal Time Coordinated VFR : Visual Flight Rules VHF : Very High Frequency VMC : Visual Meteorological Condition Final Report RP-C6923, Cessna 172K 1 1. FACTUAL INFORMATION Aircraft Registration No. : RP- C6923 Aircraft Type/Model : Textron Aviation Inc./Cessna 172K Operator : Leading Edge International Aviation Academy, Inc. Address of Operator : 2F Col Godofredo M Juliano (Ret) Bldg., L14 B86 Bayani Road Corner Roxas Ave., AFPOVAI Phase 5, Western Bicutan, Taguig City, Philippines Place of Occurrence : San Fernando Community Airport (RPUS), Brgy. Canaoay, San Fernando Free Post Zone, San Fernando City, La Union, Philippines Date/Time of Occurrence : May 21, 2024/ 0827H(Local)/0027UTC Type of Operation : Flight Training Phase of Flight : Take-off Type of Occurrence : Reciprocating engine-non-mechanical failure 1.1 History of Flight On May 21, 2024, around 0827H, a Textron Aviation Inc. Cessna 172K type of aircraft with registration number RP-C6923 sustained substantial damage following a forced landing in the waters of Barangay Canaoay, San Fernando City, La Union, Philippines. The aircraft is owned and operated by Leading Edge International Aviation Academy Inc. (LEIAAI), based at San Fernando Airport. The accident occurred after take-off, following two (2) touch-and-go at RWY 19 San Fernando Airport (RPUS). The aircraft departed at around 0800H from the same airport for scheduled flight training for the flight instructor. Onboard the aircraft were the Flight Instructor (FI) seated on the left side of the cockpit and a Flight Instructor Trainee (FIT) on the other side. During take-off after the second touch-and-go, the aircraft experienced a total loss of engine power. The flight was on the upwind leg, traveling about 60 knots at about 250–300 feet above ground level, when the flight crew noticed the propeller stopped and a total loss of engine RPM. At this point, the FI immediately took control of the aircraft and made a right-turn attempt to return it to the runway, but to no avail. The FI immediately informed the RPUS Flight Service Station (FSS) about their situation and decided to execute a forced landing on Final Report RP-C6923, Cessna 172K 2 the water in Barangay Canaoay, San Fernando City, La Union. The aircraft ditched at a 45- degree angle, and upon impact, the nose cowling got separated. The aircraft scoured the corals for about 25 meters until it flipped over and came to rest in an inverted position about 25 meters from the shoreline. Fishermen nearby witnessed the occurrence and immediately went to help the aircraft occupants. The aircraft's final position was at coordinates 16o58872” N, 120o 300753” E, with a heading of 224o (Figure 1). Meteorological Visual Condition (VMC) prevailed during the flight, with visibility at 8 miles. A VFR training flight plan was filed. The aircraft incurred substantial impact damage to both wings, a vertical stabilizer, a broken windshield, and a bent propeller. Additionally, the two (2) occupants on board the aircraft sustained minor injuries. The responding fisherman assisted the FIT, while the FI managed to exit the aircraft on his own. Both pilots were later brought to the LORMA Medical Center for further medical treatment and was released after incurring minor injuries. Responding teams from the Philippine Coast Guard (PCG) and the San Fernando City Disaster Risk Reduction Management Office (CDRRMO) rendered assistance to the accident site as first responders. Figure 1. The aircrafts final resting point. 1.2 Injuries to Persons Injuries Crew Passengers Others TOTAL Missing/Fatal 0 0 0 0 Serious 0 0 0 0 Minor 2 0 0 2 None 0 0 0 0 1.3 Damage to Aircraft The aircraft sustained substantial damage. Final Report RP-C6923, Cessna 172K 3 1.4 Other Damages There were no reported other damages during the site investigation. 1.5 Personnel Information 1.5.1 Flight Instructor (FI) 1.5.2 Flight Instructor Trainee (FIT) 1.6 Aircraft Information The Cessna 172 Skyhawk is a single-engine, high wing, fixed-wing aircraft by the Cessna Aircraft Company. It was first flown in 1955 and more 172s have been built than any other aircraft. It was developed from the 1948 Cessna 170 but with tricycle landing gear rather than conventional landing gear. 1.6.1 Aircraft Data Registration Mark : RP-C6923 Manufacturer : Textron Aviation Inc. Country of Manufacturer : USA Type/Model : Textron Aviation Inc./Cessna C172K Serial No. : 17258662 Date of Manufacture : 1970 Certificate of Airworthiness : September 18, 2024 Certificate of Registration : May 27, 2025 Gender : Male Date of Birth : October 29, 1982 Nationality : Philippines License : 126867-FI valid until September 30, 2024 126867-CPL valid until October 31, 2025 Type rating : Airplane: Single Engine Land-C172 Medical Certificate Valid until : Class I, May 22, 2024 Total Flying Time : 5,156+00 Hours Total Flying Time On type : 4,956+00 Hours Gender : Male Date of Birth : November 23, 1999 Nationality : Philippines License : 156279 -Commercial Pilot License (CPL) Valid up to : January 14, 2029 Type rating : Airplane: Single Engine Land-C152, C172 Medical Certificate Valid until : Class I, May 23, 2025 Total Flying Time : 198+22 Hours Total Flying Time On type : 198+22 Hours Final Report RP-C6923, Cessna 172K 4 Category : Normal Number of Occupants : 4 Gross Weight : 1,043.20 Kilos Airframe total time : 12,263+48 Hours since last C of A 1.6.2 Engine Data The Lycoming O-320 is a large family of naturally aspirated, air-cooled, horizontally opposed four-cylinder direct-drive engine produced by Lycoming Engines. It was introduced in 1953 and was commonly used on light aircraft such as Cessna 172 and Piper Cherokee, and remains in production as of 2024. Different variants are rated for 150 or 160 horsepower (112 or 119 kilowatts). The E2D engine variant is a 150 hp (112 kW) at 2700 rpm, Minimum fuel grade 80/87 avgas and compression ratio 7.00:1. Similar to E2A it is used in the Cessna 172 I to M models. Manufacturer : Lycoming Type/Model : Piston/O320-E2D Engine Serial Number : L-38396-27A Time Between Overhaul : 2,400 Hours Time Since New : 2,246 Hours 1.6.3 Propeller Data McCauley Propeller Systems is an American aircraft propeller manufacturer, founded in Dayton, Ohio in 1938. It was the world’s largest aircraft propeller manufacturer of general aviation propellers. The DTM7553 is a six (6) bolt aluminum fixed pitch propeller with an FAA type certificate: P910 and is most popular for Cessna C172 type of aircraft. 1.7 Meteorological Information Visual Meteorological Conditions (VMC) prevailed at the time of the occurrence. 1.8 Aids to Navigation The flight was carried out under Visual Flight Rules (VFR). Using VFR, the pilot must be able to operate the aircraft with visual references to the ground and visually avoiding obstructions and other aircraft. Manufacturer : McCauley Type : Fixed Pitch Type/Model : Constant Speed C160/DTM7553 Propeller SN# : 727524 Date last Installed : December 2023 Propeller total time : 168+20 Hours as per aircraft logbook Final Report RP-C6923, Cessna 172K 5 1.9 Communications The aircraft is equipped with operational Very High Frequency (VHF) transceiver used for communicating with aerodrome personnel and other aircrafts in the area. Air traffic over the aerodrome is directly controlled by San Fernando Tower at 122.1MHz. 1.10 Aerodrome Information San Fernando Community Airport (RPUS) is located at San Fernando Airport, Canaoay San Fernando City, La Union 2500 Philippines and is listed as Community Aerodrome Facility under the Air Traffic Management Service Aerodrome Information Publication (AIP). 1.10.1 General Information Aerodrome Name : San Fernando Community Airport (RPUS) Coordinates : 163540.2182N 1201811.2422E Aerodrome Operator : Poro Point Management Corporation, Poro Point Freeport Zone Runway Direction : 01 /19 (007º 02’ MAG)/(187º 02’ MAG) Runway Length : 2120 meters Runway Width : 45 meters Runway Elevation : 4.659M (15.285FT) Surface : PCN 46 R/A/W/T CONC Apron : Surface: CONC. Strength: PCN 49 R/B/W/T ATS Facility: Tower : San Fernando Tower-122.10Mhz (Primary) Types of traffic permitted : VFR AD Operator : Airport Operations: 0000 - 0800. Rescue and firefighting service: 2200 - 0800. Security : H24 Restaurants : At the town proper Transportation : Vehicle for hire. ANS Facility - VOR : SAN 114.50Mhz (164342.1485N 1202129.1880E) Visual Ground Aids : Standard day markers and wind direction indicator. Facilities : Clinic, rescue and firefighting equipment, radio transceivers and land transportation. AD category for fire fighting : CAT IV Rescue equipment : Two (2) fire trucks. Ziegler V8 fire truck with water capacity of 9 000 liters and foam capacity of 900 liters. SIDES VMA 28 fire truck with water capacity of 2,500 liters and foam capacity of 300 liters. Capability for removal of disabled aircraft : Nil. Runway (RWY) and Taxiway (TWY) markings and light (LGT) : RWY designation markings, threshold markings, RWY centerline markings, Touchdown zone markings, RWY side stripes, aiming points, Distance-to-go, Yellow lines to taxiway. TWY: TWY centerline markings. Final Report RP-C6923, Cessna 172K 6 Aerodrome Obstacles : 01/19 APCH zone: Trees, antenna, and high-tension wire 1.11 Flight Recorders The aircraft is not equipped with any flight recorders and existing Philippine Civil Aviation Regulation does not require it. 1.12 Wreckage and Impact Information The flight instructor executed a forced landing into the waters of Barangay Canaoay, San Fernando City, La Union, which is about 185 meters away from the west-side portion of runway 01. At a 45-degree angle, the aircraft plunged into the water, causing the nose cowling to separate upon impact. It then scoured the corals for approximately 25 meters before flipping over and coming to rest in an inverted position approximately 25 meters from the shoreline. The aircraft's final position was at coordinates 16o58872” N, 120o 300753” E, and its heading was at 224o. The aircraft incurred substantial impact damage to both wings, vertical and horizontal stabilizers, a broken windshield, and a bent propeller, with no reported post-fire damage. As a result, the two (2) passengers on board the aircraft sustained minor injuries. Local barangay emergency units were dispatched, and the PCG also helped secure the aircraft. Figure 2: The damages incurred by RP-C6923. 1.13 Medical and Pathological Information Both pilots have undergone the post-accident medical examination at CAAP-OFSAM on June 4, 2024, and there were no medical impediments that could hinder their fitness to fly. Final Report RP-C6923, Cessna 172K 7 With minor injuries, the two (2) pilots were able to egress from the aircraft (FI on his own and FIT with the help of responding witnesses to the accident). Both pilots were brought to LORMA Medical Center for treatment. The FI suffered multiple abrasions, a lacerated wound, left supraorbital area S/P suturing, and soft tissue contusions on the left thigh, while the FIT suffered abrasions on the right forearm. Following treatment, the hospital released both pilots for bed rest. Both pilots were able to undergo drug tests at the Ilocos Training and Regional Medical Center, with negative results that could affect aircrew flight performance. 1.14 Fire There was no reported post-crash fire during on-site investigation. 1.15 Search and Survival Aspects The accident was survivable because it occurred at a nearby airport. Fisher folks, local emergency responders, and the PCG were able to reach the site immediately. On the day of the occurrence, AAIIB investigators arrived late in the afternoon and deactivated the aircraft ELT, finding it operational and functioning according to its standard specifications. It was transmitting the distress signal at the time of the event and was monitored by receiving stations nationwide. 1.16 Test and Research The operator, along with their mechanics, conducted an inspection of the aircraft structures for damage assessment, which AAIIB investigators witnessed on May 21, 2024. On May 22, 2024, the operator recovered the aircraft engine and conducted a teardown inspection at the LEIAAI AMO facility on the same day. The LEIAAI AMO personnel carried out the activity, with AAIIB investigators observing until the engine teardown examination concluded. The AMO reported the discovery of impact damage in the engine's internal mechanical parts. The examination of the crankshaft, camshaft, connecting rods, cylinder valves, and valve trains showed that these components were all in good condition. The engine teardown report showed no damage to the engine's auxiliary drives or exhaust system. However, the report stated that an examination of the fuel gas strainer sediment bowl revealed the presence of water contaminants. The sparkplugs also indicated the presence of metal oxide deposits. The aircraft intake manifold received impact damage. 1.17 Organizational and Management Information 1.17.1 Operator Leading Edge International Aviation Academy, Inc. (LEIAAI) has an Aircraft Training Organization Certificate (ATOC) #2008-14 valid until January 20, 2027 authorized to perform Flight ang Ground training operations that provides private pilot course, Final Report RP-C6923, Cessna 172K 8 commercial pilot course, instrument rating course, flight instructor course and refresher for single engine land services. LEIAAI flight operations is located at San Fernando Community Airport, Canaoay, San Fernando City, La Union. The aircraft RP-C6923, is listed on their ATOC Operations specification. 1.17.2 Maintenance LEIAAI is also a holder of an Approved Maintenance Organization Certificate (AMOC) # AMO-90-10 empowered to operate as an Approved Maintenance Organization in compliance with the requirements of the Civil Aviation Regulation (PCAR) Part 6 with official address at San Fernando Airport, Poro Point Freeport Zone, San Fernando City, La Union, Philippines with limited ratings on Airframe and Powerplant valid up to June 30, 2025.The maintenance function of RP-C6923 is being undertaken by Leading Edge International Aviation Academy, Inc. Repair Station. 2. ANALYSIS 2.1 General PCAR properly certified and qualified the flight instructor and authorized the operator to conduct flight training. The flight Instructor trainee has no evidence of any pre-existing medical or physical conditions that might have adversely affected his performance during the flight. At approximately 0730H, the company mechanic positioned the aircraft at the company holding point and serviced it with fuel outside the company hangar, using an electric fuel pump for fuel transfer. The usual three hundred sixty (360) degree inspections were performed to include fuel and engine checks, magneto, and static runs for about 10–15 minutes. At about 0800H, the aircraft is ready for its flight training utilization. Prior to the flight, at about 0800H the FIT filed a flight plan with San Fernando Tower with lessons on “Airwork Manoeuvre’s” and “flight instructional technique” to complete the remaining two (2) hours of the FI course. The FIT was briefed by his FI for the flight, with lessons covering flying the pattern and performing two (2) touch-and-go after which he will proceed to training point LUNA for the airworks. After performing the usual 360- degree check on the aircraft, the crew went on board and started the engine with FIT as pilot flying. Following the successful completion of the second touch-and-go, the aircraft resumed its flight. The crosswind climb proceeded smoothly until the aircraft encountered a complete loss of engine power while making a right turn for the upwind leg climb at a height of 250–300 feet above ground level, reaching speeds of approximately 60 KIAS. 2.2 Flight Training 2.2.1 Flight Instructor Rating Training Requirement The applicant for an FI rating shall have completed not less than 200 hours of flight time on single-pilot aircraft of the appropriate category. This is one of the requirements for Final Report RP-C6923, Cessna 172K 9 obtaining a Flight Instructor License - Airplane (FI-A). Under this, the FIT had to undergo the necessary flight and ground training and instructional techniques, such as: (i) Have received instruction in flight instructional techniques including demonstration, student practices, recognition and correction of common student errors; and (ii) Have practiced instructional techniques in those flight maneuvers and procedures in which it is intended to provide flight instruction listed in IS: 2.3.3.11 Appendix A or B, as applicable. (iii) The above trainings are in consonance with the requirements stipulated in PCAR Part 2. In line with this requirement, the FIT was scheduled to finish the last two (2) hours for FI training on May 21, 2024. LEIAA’s records show that this was the SP’s last dual flight training. 2.3 Aircraft Fuel Servicing In the course of the investigation, it was revealed that the operator acquires fuel through storage drums from a fuel depot outside the airport facility and stores it outside the LEIAAI hangar (Figure 3). The operator uses an electric fuel pump with a filter or strainer to transfer fuel from the stored drum to a small container, which is then serviced to the aircraft by gravity fed through the use of a chamois (cloth) that serves as another fuel filter. (Figure 4). Using a chamois does not guarantee the removal of water residue from the fuel. A review of the Company Operations Manual Standard Operating Procedures (SOP) reveals that there are inconsistencies in the procedure for dispensing aviation fuel. There were no company records found regarding the replacement schedule of the chamois, drum usage, or filters. Figure 3. The operator utilized fuel drums for aircraft fueling and storage. Final Report RP-C6923, Cessna 172K 10 Figure 4. The electric fuel pump and cart to deliver the drum from the field. An interview was also conducted with the maintenance personnel to determine the conditions, acts, or safety deficiencies that might have caused or contributed to the occurrence. It further revealed that, from the storage area, the drum is being transferred to the ramp by way of a drum cart. After opening the stored drum, a hose is used to siphon the fuel up to the bottom of the drum by use of an electric pump without allowing or determining the presence of sediments and other contaminants in the fuel. Figure 5. The hose used to siphon fuel from the drum. Final Report RP-C6923, Cessna 172K 11 Figure 6. The fuel transfer from the drum through the electric pump to small containers. Since fuel is kept, transferred, and purchased out-of-sight, the buildup of water in stored fuel drums can be extremely difficult to spot, unless it is properly tested. Water can enter the fuel in a number of different ways. Fuel is a hygroscopic fluid, meaning that it is able to absorb moisture from the air around it. This could become a problem in fuel tanks where full capacity is not maintained for extended periods of time, which is considered in maintenance preparation. It was also observed that no record of maintenance on the fuel drums was found. The inadequate maintenance program of the operator to detect the unforeseen fuel contamination of their fuel supply can result in the progressive fatigue of fuel drums in their storage facility. Another type of water contaminant is free water. Free water develops as a layer beneath stored fuel after phase separation occurs. With the presence of free water in a fuel storage drum comes the possible proliferation of microbial growth within the fuel. When the presence of free water is ignored, microbial growth will live and grow in the layer where the water meets the fuel. Hydrocarbons in fuel provide food and energy for the “fuel bug” (that is often referred to as “algae”) to rapidly spread. Once microbial growth exists in a fuel tank, sludge develops as a waste byproduct of the hydrocarbons being consumed by the microbes. In the light of this case, the variable efficacy of the fuel in the tanks would have led to water periodically entering the tank, although it is likely that this could have been removed by the daily water drain checks. Further interviews with the maintenance personnel stated that they performed the routine fuel drain check before the flight. However, the aircraft log book on the day of the accident did not show the water drain check being performed. This suggests the potential omission of the water drain check. 2.4 Aircraft Fuel & Ignition System Tests were conducted on the engine mechanical fuel pump, but due to the aircraft engine being exposed to salt water, the amount of contamination greatly affected the aircraft fuel system. Sealed components of the fuel system were practically examined and analysed regarding the fuel flow of the engine. Final Report RP-C6923, Cessna 172K 12 Based on the engine teardown activity report, the examination of the fuel gas strainer sediment bowl was also accomplished (Figure 7). It was separately removed from the engine carburetor system, and upon its disassembly, the fuel in the bowl was collected in a clean, clear glass. It revealed traces of a significant amount of water in the fuel. (Figure 8). Confirming that water had entered the fuel supply from the aircraft wing tanks to the engine. This water travels to the carburetor and then enters the fuel distribution system, obstructing the normal operation of the spark plugs and the engine's ability to generate power. Figure 7. The fuel gas strainer sediment bowl. Figure 8. The fuel from gas strainer sediment bowl. Ocular inspection of the spark plugs was also performed. The examination of the spark plugs signifies that five (5) out of eight (8) spark plugs that were removed from the engine have traces of fuel water contamination, and some showed metal oxide deposits (Figure 9). This confirmed that the engine ceased operating due to the presence of a significant amount of water contamination in the system, hampering the spark plugs normal operation. Final Report RP-C6923, Cessna 172K 13 Figure 9. The engine spark plugs evident water contamination. 3. CONCLUSIONS 3.1 Findings a. Both pilots were qualified to operate the Textron Aviation Inc. Cessna C172K type of aircraft. b. Both pilots have valid licenses and medical certificates issued by the CAAP. c. Both pilots safely egressed the aircraft with minor injuries. d. The aircraft was properly released for flight without any discrepancies noted in its logbook. e. The aircraft has current Certificates of Airworthiness and Registration. f. A visual meteorological condition prevailed at the time of the occurrence. g. The aircraft engine was subjected to a teardown inspection to validate the investigation. h. The aircraft fuel system was inspected for the presence of water contaminants. 3.2 Probable Cause 3.2.1 Primary Cause Factor a. The presence of water contaminants in the engine fuel system resulted in engine failure. 3.2.2 Contributory Cause Factors: a. Lack of fueling procedures that lead to serious safety hazards. Final Report RP-C6923, Cessna 172K 14 4. SAFETY RECOMMENDATION 4.1 The safety deficiencies detailed in this report have been fully addressed as a result of the safety measures implemented by the Operator. Consequently, no further safety recommendations are being proposed. 5. SAFETY ACTIONS 5.1 Following the occurrence, Leading Edge International Aviation Academy, Inc. initiated the following safety corrective actions: (Appendix A) a. Conducted Line Proficiency Check to the flight crew, focusing on company fuel check procedures and their responsibilities. b. Updating of Company Operations Manual, including established procedure on dispensing of aviation fuels and information dissemination on maintenance personnel regarding aircraft fueling. (Appendix “B”) ------END-----