Atlanta-William Berry Hartsfield

The twin-engine airplane, flown by a commercial pilot, was departing on a business flight from runway 31 when the right engine lost power. According to a pilot-rated witness, the airplane was about halfway down the 6,500 ft runway at an altitude of about 100 ft above ground level when he heard a "loud pop" and then saw the airplane's right propeller slow. The witness reported that the airplane yawed to the right and then began a right turn toward runway 18 with the right engine's propeller windmilling. The witness further reported that the airplane cleared a tree line by about 150 ft, rolled right, descended straight down to ground impact, and burst into flames. Postaccident examination of the airplane's right engine revealed that the crankshaft was fractured adjacent to the No. 2 main bearing, which had rotated. The crankcase halves adjacent to the No. 2 main bearing were fretted where the case through-studs were located. The fretting of the mating surfaces was consistent with insufficient clamping force due to insufficient torque of the through-stud nuts. Records indicated that all six cylinders on the right engine had been replaced at the airplane's most recent annual inspection 8 months before the accident. In order to replace the cylinders, the through-stud nuts had to be removed as they also served to hold down the cylinders. It is likely that when the cylinders were replaced, the through-stud nuts were not properly torqued, which, over time, allowed the case halves to move and led to the bearing spinning and the crankshaft fracturing. During the accident sequence, the pilot made a right turn in an attempt to return to the airport and did not feather the failed (right) engine's propeller, allowing it to windmill, thereby creating excessive drag. It is likely that the pilot allowed the airspeed to decay below the minimum required for the airplane to remain controllable, which combined with his failure to feather the failed engine's propeller and the turn in the direction of the failed engine resulted in a loss of airplane control.

The aircraft was landing on runway 13 at LaGuardia Airport (LGA), New York, New York, when it departed the left side of the runway, contacted the airport perimeter fence, and came to rest with the airplane’s nose on an embankment next to Flushing Bay. The 2 pilots, 3 flight attendants, and 98 of the 127 passengers were not injured; the other 29 passengers received minor injuries. The airplane was substantially damaged. Flight 1086 was a regularly scheduled passenger flight from Hartsfield-Jackson Atlanta International Airport, Atlanta, Georgia, operating under the provisions of 14 Code of Federal Regulations Part 121. An instrument flight rules flight plan had been filed. Instrument meteorological conditions prevailed at the time of the accident. The captain and the first officer were highly experienced MD-88 pilots. The captain had accumulated about 11,000 hours, and the first officer had accumulated about 3,000 hours, on the MD-88/-90. In addition, the captain was previously based at LGA and had made many landings there in winter weather conditions. The flight crew was concerned about the available landing distance on runway 13 and, while en route to LGA, spent considerable time analyzing the airplane’s stopping performance. The flight crew also requested braking action reports about 45 and 35 minutes before landing, but none were available at those times because of runway snow clearing operations. The unavailability of braking actions reports and the uncertainty about the runway’s condition created some situational stress for the captain, who was the pilot flying. After runway 13 became available for arriving airplanes, the flight crews of two preceding airplanes (which landed on the runway about 16 and 8 minutes before the accident landing) reported good braking action on the runway, so the flight crew expected to see at least some of the runway’s surface after the airplane broke out of the clouds. However, the flight crew saw that the runway was covered with snow, which was inconsistent with their expectations based on the braking action reports and the snow clearing operations that had concluded less than 30 minutes before the airplane landed. The snowier-than-expected runway, along with its relatively short length and the presence of Flushing Bay directly off the departure end of the runway, most likely increased the captain’s concerns about his ability to stop the airplane within the available runway distance, which exacerbated his situational stress. The captain made a relatively aggressive reverse thrust input almost immediately after touchdown. Reverse thrust is one of the methods that pilots use to decelerate the airplane during the landing roll. Reverse thrust settings are expressed as engine pressure ratio (EPR) values, which are measurements of engine power (the ratio of the pressure of the gases at the exhaust compared with the pressure of the air entering the inlet). Both pilots were aware that 1.3 EPR was the target setting for contaminated runways.As reverse thrust EPR was rapidly increasing, the captain’s attention was focused on other aspects of the landing, which included steering the airplane to counteract a slide to the left and ensuring that the spoilers had deployed (a necessary action for the autobrakes to engage). The maximum EPR values reached during the landing were 2.07 on the left engine and 1.91 on the right engine, which were much higher than the target setting of 1.3 EPR. These high EPR values likely resulted from a combination of the captain’s stress; his relatively aggressive reverse thrust input; and operational distractions, including the airplane’s continued slide to the left despite the captain’s efforts to steer it away from the snowbanks alongside the runway. All of these factors reduced the captain’s monitoring of EPR indications. The high EPR values caused rudder blanking (which occurs on MD-80 series airplanes when smooth airflow over the rudder is disrupted by high reverse thrust) and a subsequent loss of aerodynamic directional control. Although the captain stowed the thrust reversers and applied substantial right rudder, right nosewheel steering, and right manual braking, the airplane’s departure from the left side of the runway could not be avoided because directional control was regained too late to be effective.

The aircraft crashed during takeoff from Blue Grass Airport, Lexington, Kentucky. The flight crew was instructed to take off from runway 22 but instead lined up the airplane on runway 26 and began the takeoff roll. The airplane ran off the end of the runway and impacted the airport perimeter fence, trees, and terrain. The captain, flight attendant, and 47 passengers were killed, and the first officer received serious injuries. The airplane was destroyed by impact forces and post crash fire. The flight was operating under the provisions of 14 Code of Federal Regulations Part 121 and was en route to Hartsfield-Jackson Atlanta International Airport, Atlanta, Georgia. Night visual meteorological conditions prevailed at the time of the accident.

On February 7, 2006, about 2359 eastern standard time, United Parcel Service Company flight 1307, a McDonnell Douglas DC-8-71F, N748UP, landed at its destination airport, Philadelphia International Airport, Philadelphia, Pennsylvania, after a cargo smoke indication in the cockpit. The captain, first officer, and flight engineer evacuated the airplane after landing. The flight crewmembers sustained minor injuries, and the airplane and most of the cargo were destroyed by fire after landing. The scheduled cargo flight was operating under the provisions of 14 Code of Federal Regulations Part 121 on an instrument flight rules flight plan. Night visual conditions prevailed at the time of the accident.

Shortly after takeoff, the airplane experienced electrical problems, including numerous tripped circuit breakers. The flight crew requested a return to airport. During the landing rollout, the lead flight attendant and air traffic control personnel reported to the flight crew that smoke was coming from the left side of the airplane; subsequently, the flight crew initiated an emergency evacuation on one of the taxiways. Examination of the airplane revealed fire damage to the left, forward areas of the fuselage, cabin, and forward cargo compartment. The greatest amount of fire damage was found just aft of the electrical disconnect panel located at fuselage station 237. There was no evidence that the drip shield normally installed over the disconnect panel was present at the time of the accident. Bluish stains caused by lavatory rinse fluid were observed on surfaces near the disconnect panel on the accident airplane and in the same areas on another of AirTran's DC-9 airplanes. Examination of one of the connectors from the disconnect panel on the accident airplane revealed light-blue and turquoise-green deposits on its internal surfaces and evidence of shorting between the connector pins. It could not be determined when the drip shield over the disconnect panel was removed; however, this likely contributed to the lavatory fluid contamination of the connectors. Following the accident, AirTran revised its lavatory servicing procedures to emphasize the importance of completely draining the waste tank to avoid overflows. Boeing issued an alert service bulletin recommending that operators of DC-9 airplanes visually inspect the connectors at the FS 237 disconnect panel for evidence of lavatory rinse fluid contamination and that they install a drip shield over the disconnect panel. Boeing also issued a service letter to operators to stress the importance of properly sealing floor panels and adhering to lavatory servicing procedures specified in its DC-9 Maintenance Manual. The Safety Board is aware of two incidents involving the military equivalent of the DC-9 that involved circumstances similar to the accident involving N826AT. Drip shields were installed above the FS 237 disconnect panels on both airplanes.

Examination of the area of the fire origin revealed that relay R2-53, the left heat exchanger cooling fan relay, was severely heat damaged, as were R2-54 and the other relays in this area. However, the R2-53 relay also exhibited loose terminal studs and several holes that had burned through the relay housing that the other relays did not exhibit. The wire bundles that run immediately below the left and right heat exchanger cooling fans and the ground service tie relays exhibited heat damage to the wire insulation, with the greatest damage located just below the R2-53 relay. The unique damage observed on the R2-53 relay and the wire damage directly below it indicates that fire initiation was caused by an internal failure of the R2-53 relay. Disassembly of the relay revealed that the R2-53 relay had been repaired but not to the manufacturer's standards. According to the manufacturer, the damage to the relay housing was consistent with a phase-to-phase arc between terminals A2 and B2 of the relay. During the on-scene portion of the investigation, three of the four circuit breakers in the left heat exchanger cooling fan were found in the tripped position. To determine why only three of the four circuit breakers tripped, all four were submitted to the Materials Integrity Branch at Wright-Patterson Air Force Base, Dayton, Ohio, for further examination. The circuit breakers were visually examined and were subjected to an insulation resistance measurement, a contact resistance test, a voltage drop test, and a calibration test (which measured minimum and maximum ultimate trip times). Testing and examination determined that the circuit breaker that did not trip exhibited no anomalies that would prevent normal operation, met all specifications required for the selected tests, and operated properly during the calibration test. Although this circuit breaker appeared to have functioned properly during testing, the lab report noted that, as a thermal device, the circuit breaker is designed to trip when a sustained current overload exists and that it is possible during the event that intermittent arcing or a resistive short occurred or that the circuit opened before the breaker reached a temperature sufficient to trip the device.

The first officer of AirTran Airways flight 890, which preceded AirTran flight 867 in the accident airplane, identified and reported a leak from the right engine of the Boeing 737-200 during a postflight inspection at William B. Hartsfield Atlanta International Airport (ATL), Georgia. AirTran mechanics at ATL identified the source of the leak as a chafed hydraulic pressure line to the right thrust reverser. They found the part in the illustrated parts catalog (IPC), which was not designed as a troubleshooting document and does not contain sufficient detail for such use. One of the mechanics telephoned an AirTran maintenance controller in Orlando, Florida, for further instructions. The mechanics who initially identified the source of the leak had little experience working on the Boeing 737 because they had worked for ValuJet Airlines, which flew DC-9s only, until ValuJet and AirTran merged in September 1997. On the basis of the information provided by the mechanic, and without questioning his description of the line or verifying the part number that he had provided against the IPC or some other appropriate maintenance document, the maintenance controller instructed the mechanic to cap the leaking line and deactivate the right thrust reverser in accordance with AirTran's Minimum Equipment List procedures. However, instead of capping the hydraulic pressure line, the mechanics capped the right engine hydraulic pump case drain return line. The mechanics performed a leak check by starting the auxiliary power unit and turning on the electric hydraulic pumps to pressurize the airplane's hydraulic systems; no leaks were detected. Although the mechanics were not required by company procedures to test their repair by running the engines, this test would have alerted the mechanics that they had incorrectly capped the hydraulic pump case drain line, which would have overpressurized the hydraulic pump and caused the hydraulic pump case seal to rupture. However, because the mechanics did not perform this test, the overpressure and rupture occurred during the airplane's climb out, allowing depletion of system A hydraulic fluid. Depletion of system A hydraulic fluid activated the hydraulic low-pressure lights in the cockpit, which alerted the flight crew that the airplane had a hydraulic problem. The crew notified air traffic control that the airplane would be returning to ATL and subsequently declared an emergency. The flight crew's initial approach to the airport was high and fast because of the workload associated with performing AirTran's procedures for the loss of hydraulic system A and the limited amount of time available to perform the procedures. Nevertheless, the crew was able to configure and stabilize the airplane for landing. However, depletion of system A hydraulic fluid disabled the nosewheel steering, inboard flight spoilers, ground spoilers, and left and right inboard brakes. The flight crew was able to land the airplane using the left thrust reverser (the right thrust reverser was fully functional but intentionally deactivated by the mechanics), outboard brakes (powered by hydraulic system B), and rudder. The flight crew used the left thrust reverser and rudder in an attempt to control the direction of the airplane down the runway, but use of the rudder pedals in this manner had depleted the system A accumulator pressure, which would have allowed three emergency brake applications. The use of the right outboard brake without the right inboard brake at a higher-than-normal speed (Vref for 15-degree flaps is faster than Vref for normal landing flaps) and with heavy gross weight (the airplane had consumed only 4,650 pounds of the 28,500 pounds of fuel on board at takeoff) used up the remaining friction material on the right outboard brake, causing it to fail. (The left outboard brake was still functional at this point.) The lack of brake friction material on the right outboard brake caused one of the right outboard brake pistons to overtravel and unport its o-ring, allowing system B hydraulic fluid to leak out; as a result, the left outboard brake also failed. Loss of the left and right inboard and outboard brakes, loss of nosewheel steering, and use of asymmetric thrust reverse caused the flight crew to lose control of the airplane, which departed the left side of the runway and came to rest in a ditch.

The pilot-in-command stated he was cleared for an ILS approach. He had to use spoilers to intercept the glideslope. The landing was extended at the outer marker as the airspeed was slowed through 200 knots. As the airspeed decreased the spoilers were retracted and the flaps were extended to 20-degrees. The airplane was drifting to the right and flaps were lowered to 40-degrees as the drift was corrected. The airplane floated and touched down long. The spoilers, and brakes were applied as well as full reverse. There was no braking due to hydroplaning. Examination of the crash site revealed the airplane went off the end of the runway, skidded through 200 feet of sod, vaulted off a 25 foot embankment, skidded across a road, and collided with a ditch.

ValuJet Flight 592 was a scheduled flight from Miami (MIA) to Atlanta (ATL). The inbound flight had been delayed and arrived at Miami at 13:10. Flight 592 had been scheduled to depart at 13:00. The cruising altitude was to be flight level 350 with an estimated time en route of 1 hour 32 minutes. The DC-9 was loaded with 4,109 pounds of cargo (baggage, mail, and company-owned material (COMAT)). The COMAT consisted of two main tires and wheels, a nose tire and wheel, and five boxes that were described as "Oxy Cannisters -‘Empty.’" This cargo was loaded in the forward cargo compartment. Flight 592 was pushed back from the gate shortly before 13:40. The DC-9 then taxied to runway 09L. At 14:03:24, ATC cleared the flight for takeoff and the flightcrew acknowledged the clearance. At 14:04:24, the flightcrew was instructed by ATC to contact the north departure controller. At 1404:32, the first officer made initial radio contact with the departure controller, advising that the airplane was climbing to 5,000 feet. Four seconds later, the departure controller advised flight 592 to climb and maintain 7,000 feet. The first officer acknowledged the transmission. At 14:07:22, the departure controller instructed flight 592 to "turn left heading three zero zero join the WINCO transition climb and maintain one six thousand," which was acknowledged. At 14:10:03, the flight crew heard a sound, after which the captain remarked, "What was that?" At that moment, the airplane was at 10,634 feet msl, 260 knots indicated airspeed (KIAS), and both engine pressure ratios (EPRs) were 1.84. At 14:10:15, the captain stated, "We got some electrical problem," followed 5 seconds later with, "We’re losing everything." At 14:10:21, the departure controller advised flight 592 to contact Miami on frequency 132.45 mHz. At 14:10:22, the captain stated, "We need, we need to go back to Miami," followed 3 seconds later by shouts in the background of "fire, fire, fire, fire." At 14:10:27, the CVR recorded a male voice saying, "We’re on fire, we’re on fire." At 14:10:28, the controller again instructed flight 592 to contact Miami Center. At 14:10:31, the first officer radioed that the flight needed an immediate return to Miami. The controller replied, "Critter five ninety two uh roger turn left heading two seven zero descend and maintain seven thousand." The first officer acknowledged the heading and altitude. The peak altitude reached was 10,879 feet msl at 14:10:31, and about 10 seconds a wings-level descent started. Shouting in the cabin subsided. The controller then queried flight 592 about the nature of the problem. The captain stated "fire" and the first officer replied, "uh smoke in the cockp... smoke in the cabin." The controller responded, "roger" and instructed flight 592, when able, to turn left to a heading of two five zero and to descend and maintain 5,000 feet. At 14:11:12, a flight attendant was heard shouting, "completely on fire." The DC-9 began to change heading to a southerly direction and at 14:11:26, the north departure controller advised the controller at Miami Center that flight 592 was returning to Miami with an emergency. At 14:11:37, the first officer transmitted that they needed the closest available airport. At 1411:41, the controller replied, "Critter five ninety two they’re gonna be standing (unintelligible) standing by for you, you can plan runway one two when able direct to Dolphin [a navaid] now." At 14:11:46, the first officer responded that the flight needed radar vectors. At 14:11:49, the controller instructed flight 592 to turn left heading one four zero. The first officer acknowledged the transmission. At 14:12:45, the controller transmitted, "Critter five ninety two keep the turn around heading uh one two zero." There was no response from the flightcrew. The last recorded FDR data showed the airplane at 7,200 feet msl, at a speed of 260 KIAS, and on a heading of 218 degrees. At 14:12:48, the FDR stopped recording data. The airplane’s radar transponder continued to function; thus, airplane position and altitude data were recorded by ATC after the FDR stopped. At 14:13:18, the departure controller instructed, "Critter five ninety two you can uh turn left heading one zero zero and join the runway one two localizer at Miami." Again there was no response. At 14:13:27, the controller instructed flight 592 to descend and maintain 3,000 feet. At 1413:37, an unintelligible transmission was intermingled with a transmission from another airplane. No further radio transmissions were received from flight 592. At 14:13:43, the departure controller advised flight 592, "Opa Locka airport’s about 12 o’clock at 15 miles." The accident occurred at 14:13:42. Ground scars and wreckage scatter indicated that the airplane crashed into the Everglades in a right wing down, nose down attitude.

Atlantic Southeast Airline Flight 529 was climbing through 18,000 feet, when a blade from the left propeller separated. This resulted in distortion of the left engine nacelle, excessive drag, loss of wing lift, and reduced directional control. The degraded performance resulted in a forced landing. While landing, the airplane passed through trees, impacted the ground, and was further damaged by post impact fire. An exam of the left propeller revealed the blade had failed due to a fatigue crack that originated from multiple corrosion pits in the taper bore surface of the blade spar. The crack had propagated toward the outside of the blade and around both sides of the taper bore. Due to 2 previous blade failures (separations), a borescope inspection procedure had been developed by Hamilton Standard to inspect returned blades (that had rejectable ultrasonic indications) for evidence of cracks, pits and corrosion. The accident blade was one of 490 rejected blades that had been sent to Hamilton Standard for further evaluation and possible repair. Maintenance technicians, who inspected the blade, lacked proper NDI familiarization training and specific equipment to identify the corrosion that resulted in fatigue. The captain and seven passengers were killed.