NTSB Factual Report

HISTORY OF FLIGHT

On April 26, 1998, at 1415 eastern daylight time, a Fairchild-Hiller FH-1100 helicopter, N1345Q, was destroyed during an in-flight breakup and collision with terrain while maneuvering near Stevensville, Maryland. The cockpit and cabin areas were consumed by post-crash fire. The certificated airline transport pilot and private pilot each received fatal injuries. Visual meteorological conditions prevailed for the personal flight that originated at Easton, Maryland (ESN), approximately 1300. No flight plan was filed for the flight conducted under 14 CFR Part 91.

According to the owner/operator of the helicopter, the two pilots departed ESN on a local flight to photograph area real estate. Development of film found at the accident site revealed several aerial photographs of waterfront property dated April 26, 1998.

In statements provided to the Maryland State Police, several witnesses said the helicopter was maneuvering approximately 200 feet above ground level (AGL). They heard a loud "bang" and observed pieces separate from the aircraft. The witnesses said there was no fire until after ground contact.

In a telephone interview, one witness stated she observed the helicopter from her home. She said the helicopter was maneuvering approximately 200 feet AGL when she heard a "pop". She said:

"It was flying towards my house. I heard a big pop and then a huge boom, while it was still in the air. I saw things flying off of both sides the whole time. Then it fell straight down. I could hear the aircraft. It sounded a little different but the engine had no hesitation. When I heard the pop, something flew off the top. Then I heard a bang and more things flew off. When the boom came, it just went down."

In a telephone interview, a second witness said he was standing approximately 300 feet from the accident site when he first observed the helicopter. He said the helicopter was hovering around his neighborhood from "house to house" approximately 150 to 200 feet AGL. He stated:

"The helicopter was flying north up the island. When he reached my house I noticed he made an abrupt turn towards my house. It seemed that something snapped, then he wobbled. Then he flew over my head."

The witness said the helicopter then maneuvered over the pond adjacent to the accident site. He said the helicopter was at a hover with slight forward movement when it "...fell to pieces." He further stated:

"The rotor flew off and the blade hit the cabin side...It was at a hover. The nose angled up, the rotor hit the cabin, and the person came out. The nose pitched up before the blade hit the cabin...There was engine noise all along...There was no fire for about 2 or 3 minutes."

The accident occurred during the hours of daylight approximately 38 degrees, 54 minutes north latitude, and 76 degrees, 21 minutes west longitude.

PILOT INFORMATION

The pilot held an airline transport pilot certificate with ratings for airplane single engine land, multi-engine land, and rotorcraft-helicopter. He also held a commercial pilot certificate with ratings for airplane single engine sea, multi-engine sea, rotorcraft gyroplane, and glider aero tow.

The pilot held a flight instructor certificate with ratings for airplane single and multi-engine land, rotorcraft helicopter, gyroplane, glider, and instrument airplane and helicopter. The pilot also held ground instructor and parachute rigger certificates.

A review of the pilot's logbook revealed he had 5,903 hours of flight experience, 225 hours of which was in helicopters. The pilot logged 15 hours in N1345Q beginning March 16, 1998. Prior to that date, the pilot had not flown a helicopter since November 8, 1994. The pilot logged his first flight in N1345Q as a test flight that was 1 hour in duration. Later the same day, he flew a cross-country flight that was 1 1/2 hours in duration. The pilot received a proficiency evaluation in the helicopter from the owner/operator the following day.

The pilot's most recent Federal Aviation Administration (FAA) Second Class Medical Certificate was issued on March 6, 1998.

The second pilot held a private pilot's certificate with ratings for airplane single engine land, multi-engine land, and instrument airplane. He did not possess a helicopter rating.

A review of the second pilot's logbook revealed he had 763 hours of flight experience, 1 1/2 hours of which was in the accident helicopter during the week prior to the accident. The logbook revealed 1/2 hour of dual instruction from the first pilot on April 18, 1998.

The pilot's most recent FAA Third Class Medical Certificate was issued on August 12, 1997.

The owner/operator held a commercial pilot certificate with ratings for airplane single engine land and rotorcraft helicopter. He also held a flight instructor's certificate with ratings for rotorcraft helicopter.

The owner/operator held a mechanic's certificate with ratings for airframe and powerplant.

AIRCRAFT INFORMATION

In a written statement, the owner/operator of the helicopter said the previous owner delivered the helicopter, "...via Mexico via Texas..." where it underwent an annual inspection, review of the type certificate, and review of component parts, "...with particular attention to time life components." The owner/operator also stated that the previous owner had performed extensive component overhauls in May of 1997.

The owner/operator submitted adlog maintenance records for the helicopter that he had initiated March 17, 1998. Along with those records, the owner provided photocopies of individual entries from one or more previous logbooks. One entry was for an annual inspection completed May 13, 1997.

The owner/operator also provided a typed letter from the previous owner dated December 31, 1996, that claimed recent overhaul of time limited components and their remaining service times.

An FAA Airworthiness Inspector examined the helicopter's records. At the completion of the review, he submitted an itemized list of discrepancies that spanned three pages. Among the discrepancies noted:

1. No permanent records existed for FH 1100 serial number 180, N1345Q, or the time limited components installed on the airframe as required by 14 CFR Part 91.417.

2. A mechanic with no inspection authority signed off the most recent annual inspection.

3. Weight and Balance forms were altered originals from FH1100 serial number 220.

4. A designated airworthiness representative (DAR) with no rating for helicopters issued the Airworthiness Certificate on November 19, 1997, at 7,118 aircraft hours.

5. Four months later, the helicopter owner/operator recorded complete disassembly of the aircraft to component parts, overhauls of components to zero time, and re-assembly of the helicopter with no corresponding paperwork. The owner/operator recorded the work was completed at 7,076 aircraft hours, a reduction of 42 hours of total airframe time since he purchased the helicopter.

Examination of National Transportation Safety Board Aviation Accident Report LAX88FA332 revealed that Hiller FH 1100 Serial #180, N1345Q, was destroyed in an accident on September 11, 1988. The helicopter was de-registered as "demolished" as a result of the accident. According to the accident report, the helicopter had accumulated 7,601 aircraft hours, approximately 500 hours more than that reported March 17, 1998.

At the time of the accident on April 26, 1998, an Allison 250-C18B engine, serial #CAE801550B was installed in the helicopter. The records provided indicated the engine was removed from FH 1100 serial #069, and installed in serial #180 on May 13, 1997. However, no maintenance records or history existed for this engine. An entry by the owner/operator represented that this was a "Blue Ribbon" engine, and as such, could accumulate an additional 250 hours time before overhaul. The engine and engine component total times and time since overhaul could not be determined.

Research revealed that serial #CAE801550B was installed in a Bell 206 that was destroyed in an accident in January 1983. No records of maintenance, overhaul, or component purchases for the engine since that time were found.

In an interview, the owner/operator reported the helicopter was in Hagerstown, Maryland "for two months" having radios installed. After the installation of the radios, the helicopter was test flown and then delivered to the owner by the accident pilot on March 16, 1998. The next day, March 17, 1998, the owner/operator signed off the disassembly of the helicopter; overhaul of time limited components and re-assembly of the helicopter as well as the accident pilot's flight proficiency check in the helicopter.

In a telephone interview, a witness reported that he inspected N1345Q in February 1996 as a flight test engineer of the Hiller Aircraft Company. At that time, the company was interested in the purchase of an FH-1100 for use as a ground test vehicle. He said:

"I went down and looked it over. It looked to me like it had been piece-mealed together. You could tell it was pieced together by all the different colors. [The previous owner's] reputation precedes him. A lot of the work was being done there and there was no one there qualified to do the work or to sign it off. There were discrepancies in the logbook. Some of the components came off other aircraft and I had to wonder what happened to those other aircraft to make those components available, because we stopped manufacturing parts for this aircraft in 1972."

When questioned if the time-limited components on the aircraft appeared recently overhauled, the witness replied:

"Well, they looked like they'd been painted. I was there to look at FH-1100 parts as well and we didn't buy any of those either."

When questioned as to why Hiller Aircraft Company declined to buy N1345Q, the witness said:

"We were going to use it as a ground test bed and we decided it was unsuitable for that purpose."

METEOROLOGICAL INFORMATION

Weather observed at Baltimore Washington International Airport at 1454 hours was: few clouds at 5,000 feet with a broken layer at 12,000 feet and an overcast layer at 20,000 feet. The temperature was 63 degrees and the dewpoint was 52 degrees. The winds were from 090 degrees at 3 knots.

WRECKAGE INFORMATION

Examination of the wreckage revealed that all major components were accounted for at the scene. The wreckage path was oriented 105 degrees magnetic.

The main rotor hub and blade assembly, with the top portion of the main rotor mast attached, was located approximately 190 feet prior to the main wreckage. The hub static stops exhibited paint and metal transfers from the rotor mast. The mast fracture was aligned with the bottom of the hub at the static stops. A National Transportation Safety Board metallurgist examined the fracture surfaces on the main rotor mast at the scene. He said the mast exhibited overload fractures with no evidence of fatigue.

Cyclic, collective, and tail rotor control continuity could not be established due to impact and fire damage to the cockpit and cabin areas. Control continuity was established from the cockpit area to the tail rotor blades where pitch change was established. No Stability Augmentation System (SAS) was installed on the helicopter.

Rotational damage was evident at the tail rotor driveshaft couplings and on the vertical fin. The tail rotor blades were broken outboard of their mid-point and were bent opposite the direction of rotation.

The main driveshaft was separated from the main transmission. The flex coupling at the main transmission input side was fractured. Examination by a Safety Board metallurgist revealed the driveshaft failed in overload. Three attachment bolts on the flex coupling from the engine output side did not have the corresponding self-locking nuts installed. The three bolts missing hardware were mounted in succession.

Examination of the engine revealed the induction bellmouth seal, a rubber bowl-shaped gasket, was ingested by the engine and blocked the intake area of the induction section.

The engine was removed from the site for further examination.

A cursory examination of the main transmission revealed exterior damage by fire. The fracture surface at the top of the mast exhibited overload fractures with no evidence of fatigue. The mast could not be rotated by hand. The transmission was removed for further examination.

The Master Caution segment light panel was removed for further examination.

MEDICAL AND PATHOLOGICAL INFORMATION

Dr. Dennis J. Chute, of the Chief Medical Examiners Office, Baltimore, Maryland performed autopsies on both pilots.

The FAA Toxicology Accident Research Laboratory, Oklahoma City, Oklahoma performed toxicological testing for both pilots.

TESTS AND RESEARCH

The engine was examined at Airwork Corporation, Millville, New Jersey on April 30, 1998. The examination revealed rotational scoring inside the induction, compressor, and power turbine sections. The compressor blades were bent opposite the direction of rotation. The discharge tube from the compressor section contained shiny metal particles.

All fuel and oil filters and screens were found intact and clear of obstructions. Fuel was present in the fuel control and the drive splines were intact and free to rotate. The fuel nozzle was flow tested and found free of obstructions. Continuity was established throughout the N1 and N2 sections of the engine accessory gearbox.

The transmission was examined at the Hiller Aircraft Corporation, Marina, California, on October 19, 1998. Initial examination revealed impact damage to the tail rotor drive flange and excessive fire damage to the accessory drive case at the bottom of the transmission. Disassembly began at the top of the transmission case. The mast bearings and upper planetary gears were intact and found free to rotate. The engine power input quill and one-way clutch functioned without defect.

The lower portion of the transmission, the accessory drive section, was locked up and prevented rotation of the transmission. Disassembly of this section revealed a bearing would not rotate and the bearing race was removed. According to the inspection report, "The internal inspection revealed solid carbon buildup on the inner and outer races between the balls...The carbon deposits were very hard and were left after the complete combustion of the lubricating oil. The carbon deposits were removed to determine if any pre-existing damage to the bearing was present. Upon removal of the carbon, the balls and races appeared to have been fully serviceable up to the moment of ground impact and fire."

An Aviation Safety Inspector from the Van Nuys Manufacturing Inspection District Office examined the transmission and reviewed the inspection report. The Inspector concurred with the findings of the report.

MASTER CAUTION PANEL

The individual panel segments were illegible due to fire damage, but the covers were in place. A cursory examination of the panel revealed varying degrees of filament damage and stretch in the light bulbs installed in the panel. Removal of the segment covers revealed that no light bulbs were installed in the PRIMARY HYDRAULIC caution segment or the MAIN GENERATOR caution segment.

The Materials Laboratory Division of the National Transportation Safety Board performed a detailed examination of the bulbs that were installed.

ADDITIONAL INFORMATION

In an interview, the owner/operator was asked what actions he would take with the helicopter if any caution segments failed to illuminate when the press-to-test button was pushed before engine start. He said:

"I'd get it repaired before I flew it."

According to the Hiller Aviation Service Letter 10-10 published August 3, 1983:

ABRUPT PULL-UPS AND PUSH-OVERS CAN BE CATASTROPHIC

"A recent fatal accident was caused by a pilot putting the helicopter into a low-G (weightless) flight condition. While he attempted to maneuver the helicopter with full cyclic inputs during the low-G condition, the rotor flapping at the teeter hinge exceeded design limits causing extreme 'mast bumping' fractu

NTSB Probable Cause

The pilot's abrupt, low-g maneuver, which resulted in mast bumping and separation of the main rotor system.