Convair CV-580

The 9,500-hour ATP-rated pilot was forced to secure the left engine during a maintenance test flight following the malfunction of the left propeller. The crew executed single-engine instrument landing system (ILS) approach to runway 13. During short final, the crew noticed that the alternator light was illuminated and the hydraulic pressure gauge indicated "0" pressure. The landing gear was already extended and the flaps were partially extended, so the crew elected to continue the approach to a full-stop landing. Upon landing, the pilot immediately turned on the direct current (DC) hydraulic pump. The pilot added that he then realized that he was unable to maintain directional control of the airplane due to the lack of nose wheel steering and the ineffective wheel brakes. As a result, the airplane continued to veer to the right and exited the runway. The airplane collided with the airport perimeter fence and continued down into a drainage ditch. The examination of the aircraft revealed that the hydraulic pump switch did not appear as if it had been turned on.

On August 13, 2004, about 0049 eastern daylight time, Air Tahoma, Inc., flight 185, a Convair 580, N586P, crashed about 1 mile south of Cincinnati/Northern Kentucky International Airport (CVG), Covington, Kentucky, while on approach to runway 36R. The first officer was killed, and the captain received minor injuries. The airplane was destroyed by impact forces. The flight was operating under the provisions of 14 Code of Federal Regulations (CFR) Part 121 as a cargo flight for DHL Express from Memphis International Airport (MEM), Memphis, Tennessee, to CVG. Visual meteorological conditions prevailed for the flight, which operated on an instrument flight rules flight plan. The flight crew was scheduled to fly the accident airplane on a roundtrip sequence from MEM to CVG. Flight 185 departed MEM about 2329. The first officer was the flying pilot, and the captain performed the non flying pilot duties. During postaccident interviews, the captain stated that the takeoff and climb portions of the flight were normal. According to the cockpit voice recorder (CVR) transcript, at 0017:49, the captain stated that he was just going to “balance out the fuel here.” The first officer acknowledged. From 0026:30 to 0027:08, the CVR recorded the captain discussing the airplane’s weight and balance with the first officer. Specifically, the captain stated, “couldn’t figure out why on the landing I was out and I was okay on the takeoff.” The captain added, “the momentum is one six six seven and I…put one zero six seven and I couldn’t work it.” He then stated, “so…we were okay all along.” At 0030:40, the first officer stated, “weird.” At 0032:31, the captain stated, “okay just let me finish this [the weight and balance paperwork] off and…I’m happy,” and, about 2 minutes later, he stated, “okay, back with you here.” At 0037:08, the captain contacted Cincinnati Terminal Radar Approach Control (TRACON) and reported an altitude of 11,000 feet mean sea level. About 1 minute later, the first officer stated, “something’s messed up with this thing,” and, at 0039:07, he asked “why is this thing?” At 0041:21, the first officer stated that the control wheel felt “funny.” He added, “feels like I need a lot of force. it is pushing to the right for some reason. I don’t know why…I don’t know what’s going on.” The first officer then repeated twice that it felt like he needed “a lot of force.” The CVR did not record the captain responding to any of these comments. At 0043:53, when the airplane was at an altitude of about 4,000 feet, the captain reported to Cincinnati TRACON that he had the runway in sight. The approach controller cleared flight 185 for a visual approach to runway 36R and added, “keep your speed up.” The captain acknowledged the clearance and the instruction. The first officer then stated, “what in the world is going on with this plane? sucker is acting so funny.” The captain replied, “we’ll do a full control check on the ground.” At 0044:43, the approach controller again told the captain to “keep your speed up” and instructed him to contact the CVG Air Traffic Control Tower (ATCT). At 0045:11, the captain contacted the CVG ATCT and requested clearance to land on runway 36R, and the local control west controller issued the landing clearance. Flight data recorder (FDR) data indicated that, shortly afterward, the airplane passed through about 3,200 feet, and its airspeed began to decrease from about 240 knots indicated airspeed. At 0045:37, when the airplane was at an altitude of about 3,000 feet, the captain started the in-range checklist, stating, “bypass is down. hydraulic pressure. quantity checks. AC [alternating current] pump is on. green light. fuel panel. boost pumps on.” About 0046, the first officer stated, “I’m telling you, what is wrong with this plane? it is really funny. I got something all messed up here.” The captain replied, “yeah.” The first officer then asked, “can you feel it? it’s like swinging back and forth.” The captain replied, “we’ve got an imbalance on this…crossfeed I left open.” The first officer responded, “oh, is that what it is?” A few seconds later, the first officer stated, “we’re gonna flame out.” The captain responded, “I got the crossfeed open. just keep power on.” At 0046:45, the CVR recorded a sound similar to decreasing engine rpm. Immediately thereafter, the first officer stated, “we’re losing power.” At 0046:52, the first officer stated, “we’ve lost both of them. did we?” The captain responded, “nope.” FDR data showed that, about 1 second later, a momentary electrical power interruption occurred when the airplane was at an altitude of about 2,400 feet. At 0046:55, the CVR stopped recording. Airplane performance calculations indicated that, shortly after the power interruption, the airplane’s descent rate was about 900 feet per minute (fpm). According to air traffic control (ATC) transcripts, at 0047:12, the captain reported to the CVG ATCT that the airplane was “having engine problems.” The local control west controller asked, “you’re having engine problems?” The captain replied, “affirmative.” At 0047:28, the controller asked the captain if he needed emergency equipment, and the captain replied, “negative.’” This was the last transmission received by ATC from the accident flight crew. The FDR continued recording until about 0049. The wreckage was located about 1.2 miles short of runway 36R.

On Friday 3 October 2003, Convair 580 ZK-KFU was scheduled for 2 regular return night freight flights from Christchurch to Palmerston North. The 2-pilot crew arrived at the operatorís base on Christchurch Aerodrome at about 1915 and together they checked load details, weather and notices for the flight. The flight, using the call sign Air Freight 642 (AF642), was to follow a standard route from Christchurch to Palmerston North via Cape Campbell non-directional beacon (NDB), Titahi Bay NDB, Paraparaumu NDB and Foxton reporting point. The pilots completed a pre-flight inspection of ZK-KFU and at 2017 the co-pilot (refer paragraph 1.10.4) called Christchurch Ground requesting a start clearance. The ground controller approved engine start and cleared AF 642 to Palmerston North at flight level 210 (FL 210) and issued a transponder code of 5331. The engines were started and the aircraft taxied for take-off on runway 20. At 2032 AF 642 started its take-off on schedule and tracked initially south towards Burnham NDB before turning right for Cape Campbell NDB, climbing to FL210. The flight progressed normally until crossing Cook Strait. After crossing Cape Campbell NDB, the crew changed to the Wellington Control frequency and at 2108 advised Wellington Control that AF 642 was at FL210, and requested to fly directly to Paraparaumu NDB. The change in routing was common industry practice and offered a shorter distance and flight time with no safety penalty. The Wellington controller approved the request and AF 642 tracked directly to Paraparaumu NDB. At 2113 the Wellington controller cleared AF 642 to descend initially to FL130 (13 000 feet (ft)). The co-pilot acknowledged the clearance. At 2122 the Wellington controller cleared AF 642 for further descent to 11 000 ft, and at 2125 instructed the crew to change to the Ohakea Control frequency. At 2125:14, after crossing Paraparaumu NDB, the co-pilot reported to Ohakea Control that AF 642 was in descent to 11 000 ft. The Ohakea controller responded 'Air Freight 642 Ohakea good evening, descend to 7000 ft. Leave Foxton heading 010, vectors [to] final VOR/DME 076 circling for 25. Palmerston weather Alfa, [QNH] 987.' At 2125:34 the co-pilot replied ìRoger down to 7000 and leaving Foxton heading 010 for 07 approach circling 25 and listening for Alfa. Air Freight 642. At 2125:44 the Ohakea controller replied 'Affirm, the Ohakea QNH 987.' The crew did not respond to this transmission. A short time later the controller saw the radar signature for AF 642 turn left and disappear from the screen. At 2126:17 the Ohakea controller attempted to contact AF 642 but there was no response from the crew. The controller telephoned Police and a search for AF 642 was started. Within an hour of the aircraft disappearing from the radar, some debris, later identified as coming from AF 642, was found washed ashore along Paraparaumu Beach. Later in the evening an aerial search by a Royal New Zealand Air Force helicopter using night vision devices and a sea search by local Coastguard vessels located further debris offshore. After an extensive underwater search lasting nearly a week, aircraft wreckage identified as being from ZK-KFU was located in an area about 4 km offshore from Peka Peka Beach, or about 10 km north of Paraparaumu. Police divers recovered the bodies of the 2 pilots on 11 October and 15 October.

The airline completed weight and balance and dispatch release forms for the initial flight showed an incorrect fuel load at the time the engines were started. The first officer performed a walk-around before the first flight leg which included checking the fuel tanks. A total of 460 gallons of fuel were added to the fuel tanks, and a delay loading cargo occurred. After both engines were started to begin the first flight, the engines remained operated for between 9-10 minutes before they were secured due to a radio problem. Maintenance personnel reracked the VHF radios, and again the engines were started where the airplane remained on the ramp 3-4 minutes before taxiing to the runway. The airplane remained at the runway hold short area for between 20 and 25 minutes before returning to the ramp due to a radio problem. The engines were secured, and a new VHF radio was purchased and installed. The company did not prepare new dispatch release, or weight and balance forms for the flight taking into account the additional fuel consumed with the engines operating. The engines were started, and the airplane was taxied to the runway and departed for the planned first leg. The airplane landed uneventfully at the destination airport where the cargo was offloaded. The first officer performed a walk-around which included checking the fuel tanks; 300 gallons of fuel were added to the fuel tanks (150 gallons in each side). The flight departed to return and when near the coastline, the flight was vectored to an airport other than the planned destination due to a issue with U.S. Customs. The flight landed uneventfully, and experienced a delay clearing customs. While on the ground before departure on the accident flight, the first officer reportedly performed a walk-around which included checking the fuel tanks with the captain looking on. The first officer reported that each fuel tank had approximately 1,100 pounds of fuel, and he and the captain both agreed before takeoff as to the quantity of fuel on-board as indicated by the magna-sticks. No fuel was purchased. Following starting of both engines for the accident flight, the first officer checked the fuel quantity gauges indications against the magna-sticks indications he observed; the fuel quantity gauges indicated approximately 200 pounds more. The flight departed, proceeded eastbound, and climbed to approximately 2,100 feet msl. During a right turn from a southeast to westerly heading, the right engine experienced a loss of horsepower which decreased from 900 to zero. The right engine was secured as a precaution, and priority handling to the destination airport was requested with air traffic control. The left engine horsepower remained the same (900) for a period of 31 seconds following the right engine horsepower decrease, then increased to 2,200, and remained at that value for 1 minute 13 seconds. The left engine horsepower then began to decrease and dropped to zero. The airplane was turned to the east, then turned to the south and ditched. The captain and first officer evacuated but remained with the airplane, and made it to shore where the first officer advised his wife that something was wrong with the fuel gauges. Following recovery of the airplane, pressure testing of the left fuel tank revealed no evidence of preimpact leakage. Pressure testing of the right fuel tank revealed slight leakage past the fuel cap. Boroscope examination of the engines, and functional test of each engine ignition system, fuel control units and fuel pumps revealed no evidence of preimpact failure or malfunction. Examination of the installed magna-sticks revealed no evidence of preimpact failure. The left fuel tank was drained and found to contain 2 gallons of Jet A fuel, while the right fuel tank was drained and found to contain approximately 540 gallons of salt water and 1/2 gallon of Jet A fuel. Fuel consumption calculations performed by FAA personnel revealed that at the time of engine start for the accident flight, the fuel tanks contained approximately 714 pounds of fuel. According to a representative of the engine manufacturer, the amount of fuel drained from the engine components post accident was consistent with, "low residual fuel."