MIDDLETOWN, RI, USA
N4507S
Beech A36
At 6,000 feet, the instrument-rated pilot reported an engine failure, and received vectors to an airport. After the turn, the airplane was 6 nautical miles away, at 4,000 feet. After descending through clouds, the pilot reported, at 1,200 feet, the airport in sight. The airplane then descended rapidly, straight ahead, and hit the ground upright, about 1/2 mile short of the runway. The initial impact point was at the far end of a pasture, which extended off to the pilot's right. The airplane then bounced and collided with a stone wall. Witnesses thought the airplane would make the runway, but it appeared to level off, climb slightly, then fall forward. The stall warning horn sounded upon exiting the clouds, and remained on until impact. The landing gear was in transit at impact. Radar revealed a groundspeed of 81 knots at 1,200 feet, which decreased to 62 knots by 400 feet. The operating handbook stated that power off, 81 knots were required to assure controllability during the flare. The engine crankshaft was found broken in two places. The number two bearing was pounded, and had moved in its saddle. Saddle oil lubrication holes were blocked by metal, and the crankshaft exhibited ladder cracking.
HISTORY OF FLIGHT On May 25, 1998, at 1501 Eastern Daylight Time, a Beech A36 Bonanza, N4507S, was destroyed during a forced landing about 1/2 mile north of the Newport State Airport (UUU), Newport, Rhode Island. The instrument rated private pilot and one passenger were fatally injured. Two additional passengers were seriously injured. Visual meteorological conditions prevailed at the accident site, however, the pilot had to fly through an overcast layer during the emergency descent. An instrument flight rules flight plan had been filed for the flight between Nantucket Memorial Airport (ACK), Nantucket, Massachusetts, and Danbury (DXR), Connecticut. The personal flight was conducted under 14 CFR Part 91. The airplane departed Nantucket at 1432, and climbed to 6,000 feet. At 1448, the pilot contacted Providence Air Traffic Control Tower, East Low Radar position. At 1456:01, he told the controller he had "an in-flight problem," and then reported "we've got an engine failure." The controller acknowledged, and advised the pilot that Newport State Airport was at his 9 o'clock position, 6 miles, and that Quonset State Airport was at his 10 o'clock position, about 8 miles. After giving the pilot the option of either airport, the controller told him to "fly a heading two three zero, the Newport Airport will be at twelve o'clock and five miles." The pilot acknowledged the heading. At 1457:06, the controller advised the pilot that Newport State had a Runway 22, that he would line the airplane up for that runway, that it was at 12 o'clock and 5 miles, and that the pilot was cleared to descend to and maintain 2,000 feet. The pilot acknowledged: "two thousand, zero seven." At 1457:51, the controller requested "...when you have a chance, souls on board and fuel remaining please." The pilot responded with 30 gallons of fuel and four people. At 1458:17, the controller repeated the descent instructions, and said the airport was at 12 o'clock and 3 1/2 miles. At 1458:58, the controller stated: "The overcast layer's at twenty three hundred feet. There's a few clouds at nine hundred. You should be able to see the airport shortly - it's twelve o'clock and four miles, correction, ah, three miles." The pilot responded with "twelve o'clock, three miles." At 1459:17, the controller advised the pilot that the length of Runway 22 was 3,000 feet, and that it was at 12 o'clock and 2 miles. This was acknowledged by the pilot. At 1459:46, the controller stated: "At pilot's discretion, you can maintain fifteen hundred. Airport's twelve o'clock and a mile and a half." At 1459:51 the pilot responded: "Roger, I'm just coming into the overcast now." At 1459:54, the controller stated: "Okay, should be coming out of it shortly, the airport will be twelve o'clock and a mile and a half. Runway is straight ahead." At 1500:19, the pilot stated: "Airport's in sight," and the controller responded with: "Roger, you can remain with me until you land." The pilot responded: "Zero seven." There were no further transmissions from the pilot. During this time, there was a Piper Navajo on the ground and on a different radio frequency at Newport State Airport. At 1500:53, the Navajo pilot stated he had the Bonanza in sight, and at 1501:18 said: "I'm not sure he's going to make it - he's going pretty low." At 1501:25, the Navajo pilot stated "I believe that plane has crashed...." He then reported smoke and fire and: "That plane has crashed, sir... about one-half mile off the end of Runway two two." Passengers The two surviving passengers were sitting in the main cabin of the airplane, in the rearward facing seats. Both were initially wearing headsets. One passenger, who was sitting behind the pilot, remembered that the pilot did a preflight inspection and an engine run-up prior to departure. He also remembered that the takeoff and climb were normal, except for a whistling noise, which the pilot attributed to "water caught in something." It was raining at the time. The passenger remembered that while the airplane was in level cruise flight, it suddenly and rapidly decelerated. He could not hear anything abnormal from the engine at this point because he still had his headset on. He then heard the pilot "messing with the engine; working the throttle." It sounded like something was clogging the engine, "like choking a non-starting engine; the rpm was going up and down." He didn't hear any alarms go off. He did hear the radios, and the pilot talking to both air traffic control and his daughter. At this point, the engine was still operating, and the airplane turned. The passenger thought the airplane was going back toward an airport he had seen. The turn happened "relatively quickly after the problem started." The passenger said the weather was "relatively clear," and he could see the ground. He didn't remember passing through any cloud layers during the descent, but wasn't sure. He was alternately looking both forward, "at peoples' faces," and aft. The passenger remembered three distinct phases of the event. The first started when the engine began to exhibit a problem, and included the initial steps taken toward trying to solve the problem, as well as the initial turn made by the pilot. The second phase consisted of "time passed" while the airplane was in a descent, and the passenger looking alternately forward and aft. The last phase began when the engine became silent. When the engine became silent, the passenger looked forward, and heard the pilot's daughter tell her father to restart the engine, to which he responded: "I can't." The passenger then looked toward the intended runway, just over the trees, and thought there was "no way we can make it that far." Just after that, he heard an alarm going off. He then turned back in the seat, faced aft, and buried himself down into the seat until he felt the impact. The passenger also recalled that in the last phase, the airplane made a left turn, "like a last ditch effort - plan 'B'." He thought one wing went up and one wing went down, perhaps to a 45 degree angle, but was just guessing. He thought that the left wing went down, but could not remember if the pilot held the turn or not. The passenger remembered hitting the ground, then bouncing. It was a "pretty hard" hit and his eyes were closed. After the airplane stopped, he opened his eyes, and remembered being in smoke and fire. For a few seconds, he might have blacked out. The passenger got out the plane via the right, aft passenger access door with the other passenger. He did not hear any sounds from the people in the front seats. When asked, he did not recall if or when the pilot lowered the landing gear prior to impact. The other passenger was sitting behind the right, front seat passenger. He stated that there was nothing unusual about the airplane, or the startup or takeoff, except for the new headsets. After takeoff, the passenger heard a whistling sound, "like blowing in a bottle." He said that the pilot explained that it was "water or something" and it had just been looked at by maintenance personnel. Aside from the sound, the climbout and level off were uneventful. Everything was "status quo" until the sound of the engine changed, from "humming along" to what it normally sounded like when an engine shut down. The passenger had unplugged his headset, and didn't hear many conversations from the front seats or any from air traffic control. He said that during the emergency descent, he and the other back seat passenger tried to reassure each other, and that at one time, he did hear the pilot's daughter suggest another engine restart attempt. The passenger did not remember entering any cloud layers, but remembered that when the airplane exited the last layer of clouds, he heard a horn go off. It was originally intermittent, then transitioned to a solid "wahhh" sound, and remained on until ground impact. The passenger remembered turning around in his seat at one point, and looking forward. He saw trees, and had a funny feeling that the runway was on the other side of them. He then knew "there was no shot of getting to the runway," and that the airplane was going to crash. He turned back around to face aft, and remembered the airplane "banked left and came around. He did not remember the actual impact, but did remember being on fire, screaming, and looking at the door and not knowing how to open it. He said the other passenger got up and opened the door, then doesn't remember anything else until he was out of the airplane and in the bushes. The passenger did not remember if or when the pilot lowered the landing gear. Witnesses Three witnesses were interviewed, two of whom were in an airplane waiting to take off from Newport State Airport. One witness was at his cottage in Tiverton, Rhode Island, about 12 nautical miles northeast of Newport State. He was inside the house, and heard "routine engine noise" which abruptly stopped. A few seconds later, the sound returned, then stopped again. The witness said he couldn't imagine a throttle being intentionally brought up and back at that rate. It was like there was no noise, then full throttle, then no noise again. The witness than ran outside and noted the time, which was around 3:00 p.m. The two witnesses who were in the Piper Navajo were waiting to takeoff from Runway 22 at Newport State, where the accident airplane was being vectored. One witness was sitting in the back of the Navajo. She stated that she saw the accident airplane come out of the clouds, and based on its position, was surprised it didn't make it to the airfield. She said that she thought the pilot lowered the landing gear too soon, but she did not actually see the landing gear come down. Still, she wondered: "How come he came down so fast?" The witness did not see the accident airplane make any turns once it came out of the clouds. She saw it lined up with the airport, and then it disappeared below a tree line. She also noted that there were several open fields in the vicinity of the accident. Another witness was the pilot of the Navajo. He saw the accident airplane come out of the clouds, then level off. It appeared to be 1/2 to 1/4 mile from the runway at the time. It then dropped fast, and disappeared below a tree line. The witness further described the accident airplane as being on a reasonable glideslope before it leveled off. Then it "went up slightly, then right down, forward." The witness said he thought the accident airplane may have lowered its landing gear too soon, but also said he did not actually see the landing gear come down. He noted that the accident airplane came in straight, without making any turns during the approach. The witness also stated that when his airplane took off approximately 15 to 20 minutes after the accident, it entered the cloud layer about 2,000 feet. The accident occurred during the hours of daylight. The accident site was located at 41 degrees, 32.54 minutes north latitude, and 071 degrees, 16.47 minutes west longitude. PERSONEL INFORMATION The certificated private pilot was single-engine, multi-engine, and instrument rated. His logbook was destroyed in the post-crash fire. His most recent Federal Aviation Administration (FAA) Third Class Medical Certificate was issued on November 11, 1996, and on his application he reported that he had 400 hours total flight time. He purchased the accident airplane in November, 1996, and it flew an estimated 375 hours prior to the accident. Both surviving passengers had flown with the pilot before. One stated that he did not normally feel safe in smaller airplanes, but felt safe with this pilot, who was very detail-oriented. The other passenger said he had no concerns about flying with the pilot, and "felt fine," in fact, "loved it." AIRCRAFT INFORMATION The airplane was a 1975 Beech A36, serial number E-722. It was powered by a single Continental IO-520-BA(12) engine, which developed 285 horsepower. The engine, serial number 249251-R, was rebuilt by Teledyne Continental Motors on March 21, 1985. It was installed in the airplane on April 17, 1985. The airplane had been maintained by Master Aviation, Incorporated, Danbury, Connecticut, since December, 1986. On December 20, 1989, the number 2 and number 3 engine cylinders were removed and replaced by Hangar One Incorporated, Orlando, Florida. On October 30, 1996, a prepurchase inspection was done on the airplane, on behalf of the accident pilot, by a New York maintenance facility, Curtiss Aero. At that time, the airplane tachometer registered 2099.1 hours. On October 3, 1997, Master Aviation personnel removed the propeller for overhaul. According to an invoice from an independent propeller shop, the propeller was "not economical to repair." The propeller shop manager stated that the propeller could not be brought into tolerances economically, and that there had been no indication of a prop strike. On February 20, 1998, all six engine cylinders were replaced with factory new cylinders at Master Aviation during an annual inspection. At that time, the aircraft logbook indicated 2,441.8 tachometer hours. An Airframe and Powerplant (A&P) mechanic with Inspection Authorization (IA), signed off the annual inspection. He supervised another A&P who actually changed the cylinders. The supervising IA stated that the work was performed in accordance with the maintenance manual provided on micro fiche by Aircraft Technical Publishers, Brisbane, California. Torque settings were verified with a calibrated torque wrench, which was calibrated with an on-site torque wrench tester before being used on the airplane. When asked if he remembered how, to what degree, and whether the torque's were set using wet or dry bolts and threads, the IA stated that he could not do so offhand, that he would have to have the a maintenance book in front of him to be exact, and that he would do whatever the book said to do. When asked if the engine had been split at any time during the maintenance, the IA was emphatic in that it was not. The IA said he didn't have any ideas of what might have happened to the engine because he did not have all the facts. He did say that the airplane had been in "terrific shape." He said that he wouldn't have expected problems with either the accident airplane or the accident pilot. He also noted that the owner of the maintenance facility, himself an A&P with IA, had flown the airplane on numerous occasions. The A&P mechanic who changed the cylinders said that during the maintenance, he used Continental engine overhaul manuals and backed them up with service bulletins. He said that the IA's role was to inspect and overlook his work. "The way we work it; very professional; nothing gets overlooked; everything checked, rechecked; engine run several times; torques checked per manual with a calibrated torque wrench." The torque wrench was calibrated on the day of the maintenance with a torque wrench tester. When asked if the torques were set "wet" or "dry," the A&P stated he could not remember which was done. "We work on several different aircraft; do top overhauls on a regular basis and always go back to the manuals because there are so many different manuals and installation procedures." When asked if he split the engine casing during the cylinder change, the A&P said: "No, we don't have the equipment. If it's that extreme, it goes to the manufacturer." The A&P stated that he didn't remember any problems occurring during the change of the cylinders. It was a "flawless installation; the aircraft ran like a top; [the pilot] was ecstatic with how it ran." The Continental engine overhaul manual required the use of castor oil to set wet torques, while Service Bulletin SB96-7B stated that torques should have been set using 50 weight aviation oil. The owner of Master Aviation said that 50 weight aviation oil was used and that castor oil was not on the premises. The engine's oil had been analyzed at various times between 1990 and 1997 by Cleveland Technical Center, Cleveland, Ohio. Spectrochemical analysis performed on May 31,
The shift of the number 2 engine bearing, which in turn blocked oil lubrication, and resulted in crankshaft failure. Also causal, was the pilot's decision to continue toward the airport instead of performing a forced landing to an available field. Factors include the relatively low ceiling, and the pilot's airspeed control.
Source: NTSB Aviation Accident Database
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