Friday, April 22, 2016

Cessna R172K Hawk XP, Black Sheep Aviation LLC, N758DK: Accident occurred September 03, 2015 in Cresskill, Bergen County, New Jersey

A failure by maintenance workers to properly service an aircraft engine probably led to a pilot being forced to crash-land his plane into a Cresskill field in September, according to a report by the National Transportation Safety Board.

The pilot of the plane, Jack Rosenberg, was hailed as a hero at the time for making a last-minute maneuver away from a soft landing in a field where schoolchildren were playing. Instead, Rosenberg crashed into a nearby field, destroying the airplane and seriously injuring himself and his passenger, Erik Pearson.

The two men were flying a routine patrol for the Coast Guard Auxiliary over the Hudson River in a single-engine 1978 Cessna Skyhawk on Sept. 3 when the engine failed at 2,000 feet.

The NTSB report noted that two cylinder bolts on the engine had not been fastened tightly enough and that the engine’s cylinders had last been replaced in May 2012. Since then, the plane had been in the air for 231 hours.

Failure to properly service the engine was the “probable cause” of the accident, investigators found.

Rosenberg said that a federal investigator told him that the accident was unavoidable.

“I asked if there was anything that could have been done to prevent it and he said, ‘Nothing.’ Rosenberg said.

But William D. Waldock, professor of aeronautical science at the Embry Riddle Aeronautical University, said whoever performed maintenance on the engine was to blame.

“If they’d done the maintenance right, they could have prevented it right there,” Waldock said.

Experts were united in saying Rosenberg did the best he could under the circumstances.

“He did a good job on making that field,” said J.P. Tristani, a former commercial pilot and aviation instructor who lives in Ramsey. “Unfortunately with people on the field and diverting his focus, he lost it. But he walked away with his life.”

Little space, time
Waldock said that at 2,000 feet, Rosenberg would have had two to three minutes to bring the plane down safely and only about two square miles to work with in a densely populated area.

Rosenberg aimed for what looked like empty playing fields in Tenafly, but at the last minute he spotted dozens of children. He changed course and crashed into an empty section of Cresskill’s Regan Field, where the plane skidded almost 40 feet, eventually plowing into a hedgerow.

Rosenberg and Pearson were rushed to Hackensack University Medical Center.

Rosenberg said Pearson has since returned to flying. But almost eight months later, Rosenberg, whose feet were broken in the crash, said he can barely walk, let alone climb into an airplane.

Rosenberg, a married father of seven from Spring Valley, N.Y., has not been able to return to work as a road service mechanic and he said he is often in pain.

He rejected any notion that he is a hero for swerving away from the children. “I didn’t save them. They were perfectly fine,” he said. “Had I killed any of those children I would not have been able to live with myself.”

He added that he felt lucky that the engine had not exploded in the air and that the plane did not catch fire when it crashed.

Rosenberg took off from Lincoln Park Airport around 1 p.m. Sept. 3 and picked up Pearson in Farmingdale, N.Y.

Engine died

In an interview with Cresskill police from his hospital bed, Rosenberg said he felt a vibration during the flight that he believed at the time to be turbulence. Later, the plane began to sputter and then the engine stopped completely. Rosenberg tried to restart the engine and to switch to auxiliary fuel, but all attempts failed.

The plane was too far from Teterboro Airport to make an emergency landing there, so Rosenberg picked out the playing fields on the border of Cresskill and Tenafly.

Once pilots are committed to an emergency landing spot, it is extremely dangerous to change course. Rosenberg told police that he made a last-minute right turn as soon as he saw the children.

“If I had to do it again, I wouldn’t think twice,” Rosenberg said. “And I don’t think anybody else would have done it different."

Original article can be found here:


NTSB Identification: ERA15LA338
14 CFR Public Use
Accident occurred Thursday, September 03, 2015 in Cresskill, NJ
Probable Cause Approval Date: 04/04/2016
Aircraft: CESSNA R172, registration: N758DK
Injuries: 2 Serious.

NTSB investigators may not have traveled in support of th
is investigation and used data provided by various sources to prepare this aircraft accident report.

The private pilot reported that, while the public aircraft flight was in cruise flight about 2,000 ft mean sea level, the airplane’s engine stopped producing power. During the subsequent descent, the pilot chose a large open area of several athletic fields for the forced landing. As the airplane approached the fields, the pilot observed that they were in use and that only a small space was available for landing due to people on the ground. The airplane subsequently landed hard and was destroyed during the impact.

Examination of the engine maintenance records revealed that the Nos. 3 and 4 cylinders had been removed and reinstalled 231 hours before the accident. The cylinder flange nuts and through bolts were checked for security and breakaway torque, and several were found below factory specification. Disassembly of the engine revealed metal fragments and bearing material in the oil sump. Disassembly of the crankcase revealed that it was fractured and that the Nos. 1 and 2 main bearings and bearing journals had damage consistent with a loss of lubrication, high heat, and fatigue. It is likely that maintenance personnel did not apply sufficient torque to the cylinder flange nuts and through bolts during the installation of the engine cylinders.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
Maintenance personnel’s failure to apply proper torque to the cylinder flange nuts and through bolts during installation of the engine cylinders, which resulted in the loosening of the components, loss of lubrication, failure of the crankshaft, and the subsequent total loss of engine power.

On September 3, 2015, about 1710 eastern daylight time (EDT), a Cessna R172K, N758DK, was destroyed by collision with terrain during a forced landing following a total loss of engine power near Cresskill, New Jersey. The private pilot and pilot-rated observer were seriously injured. The flight departed Republic Airport (FRG), Farmingdale, New York, about 1400. Visual meteorological conditions prevailed, and no flight plan was filed for the public use flight.

According to the United Stated Coast Guard (USCG), the flight was conducted as a USCG Auxiliary Maritime Observation Mission.

Federal Aviation Administration (FAA) inspectors interviewed the pilot in the hospital the day after the accident. Due to his injuries, the inspectors conducted only a brief interview. According to the pilot, he departed Lincoln Park, New Jersey (N07) about 1300 and flew to Farmingdale, New York (FRG) to pick up the observer for the flight. They then departed FRG, and flew to the Albany, New York area where they reversed course and flew south along the Hudson River. While in cruise flight about 2,000 feet mean sea level (msl), the airplane's engine stopped producing power.

During the subsequent descent, the pilot selected a large open area adjacent to a community center that contained several athletic fields for the forced landing. As the airplane approached, the pilot observed that the fields were in use, and that only a small space was available for landing which would allow separation from people on the ground. The resultant hard landing destroyed the airplane and required first responders to affect the egress of the airplane's occupants.

According to FAA and USCG records, the pilot held a private pilot certificate with a rating for airplane single engine land. His most recent FAA third-class medical certificate was issued on April 20, 2015. The pilot updated a USCG Pilot/Aircrew Qualification form on April 30, 2015, and reported 510 total hours of flight experience on that date. According to the FAA, the pilot reported he had 648 total hours of flight experience, of which 382 were in the accident airplane make and model.

The four-seat, single-engine, high-wing, retractable-gear airplane was manufactured in 1978 and was equipped with a Continental Motors 210-horsepower reciprocating engine. According to the FAA, the airplane's maintenance records showed the most recent annual inspection was completed on July 17, 2015, at 2,194 total aircraft hours. The hobbs meter indicated 2,281 total aircraft hours at the accident site.

Review of engine maintenance records revealed the #3 and #4 cylinders had been removed and reinstalled for maintenance on May 11, 2012. The engine accrued approximately 231.5 hours of operation prior to the accident.

Examination of photographs revealed the accident site was located in a hedgerow on the perimeter of an athletic field about 41 feet elevation. The wreckage path was approximately 36 feet long, oriented about 130 degrees magnetic. The tail section and empennage appeared intact, but the roof and wingbox structure appeared collapsed into the cockpit and cabin areas. The airplane came to rest in about a 30-degree, right wing-down attitude. The right wing was visible, and remained intact from the cabin to about mid-span, where it wrinkled and curled upwards towards the tip.

The airplane was removed from the accident site, and the engine was shipped to the manufacturer for a detailed examination at a later date.

The engine was examined at the manufacturer's facility under the supervision of an FAA aviation safety inspector. Examination revealed impact damage to the fuel pump housing, and the right magneto, which had a broken mount flange and was hanging loose from the engine. The right front engine mount was broken and several ignition harness leads were severed.

The cylinder flange nuts were checked for security and breakaway torque, and the #2 and #3 cylinders' through bolts nuts and perimeter nuts were below factory specifications. The #2 cylinder through bolts breakaway torque was 236/365 in. lbs. respectively. The #3 cylinder through bolts breakaway was 286/351 in. lbs. respectively. The manufacturer's specification was 590-610 in lbs.

Removal of the engine oil pan revealed metal fragments and bearing material in the sump. Disassembly of the crankcase revealed damage to the #1 and #2 main bearings and bearing journals consistent with a loss of lubrication, high heat, and fatigue.

Fretting was noted around the #1, #2, and #3 through bolt bosses as well as the #2 and #3 cylinder deck pads.

The crankshaft was fractured through the #4 throw.

No comments: