N185SQ

Substantial
Fatal

M-SQUARED SPRINT 1000S/N: 0554

Accident Details

Date
Saturday, September 5, 2009
NTSB Number
ERA09LA502
Location
Madeira Beach, FL
Event ID
20090908X11426
Coordinates
27.793056, -82.779441
Aircraft Damage
Substantial
Highest Injury
Fatal
Fatalities
2
Serious Injuries
0
Minor Injuries
0
Uninjured
0
Total Aboard
2

Probable Cause and Findings

A loss of torque to the gearbox engine-side coupling flange bolts, which resulted in separation of the gearbox and propeller from the engine and the subsequent severing of the airplane's tail structure.

Aircraft Information

Registration
N185SQ
Make
M-SQUARED
Serial Number
0554
Year Built
2001
Model / ICAO
SPRINT 1000

Registered Owner (Historical)

Name
YOUNG MARK J
Address
718 ROANOKE ST
Status
Deregistered
City
DUNEDIN
State / Zip Code
FL 34698-8423
Country
United States

Analysis

HISTORY OF FLIGHT

On September 5, 2009, about 0940 eastern daylight time, an experimental light sport M-Squared Sprint 1000, N185SQ, was destroyed when it impacted water in Madeira Beach, Florida. The certificated private pilot and the pilot-rated passenger were fatally injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the local flight that originated at Lake Seminole, Seminole, Florida. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91.

According to the county sheriff's incident report, one witness, a kayaker in the area, observed the airplane flying in his vicinity before landing on the water. It then water-taxied for several minutes before taking off again. The witness subsequently saw the airplane climb to about 200 to 300 feet before hearing a "pop" and seeing the airplane head straight down and impact the water.

Another witness also heard a "pop," then looked up to see the airplane "plunging toward the water" from an altitude of 300 feet. A third witness also heard the pop, and saw the airplane "nose dive" into the water. Two other witnesses observed the airplane and saw "something" happen to the airplane's propeller, then observed that parts "came off" the engine area. They then saw a parachute start to deploy before the airplane impacted the water.

In their statements, none of the witnesses indicated the presence of birds in the vicinity of the accident site.

The owner of the company that recovered the airplane from the water stated that a number of people had told him that they heard the engine "rev" before the crash.

Following the accident, the airplane was moved to a facility where a Federal Aviation Administration inspector examined it. The inspector did not provide written results of his examination; however, he did provide some photographs and noted that the airplane's ballistic parachute system had deployed, but at a low altitude, and that the propeller and gearbox were never recovered.

The inspector also provided excerpts from the pilot and aircraft logbooks, and sales receipts for the airplane, as well as engine and gearbox parts.

AIRCRAFT INFORMATION

- Airplane History -

According to FAA records, the airplane was manufactured in 2001, but not initially registered. The president of M-Squared reported that the airplane was delivered to the original owner powered by a Rotax 582 engine, driving a three-bladed pusher propeller.

FAA records indicated that the owner registered the airplane in the experimental light-sport category on January 14, 2008. The application listed 515 total airframe hours at that time and indicated that the airplane was then powered by a Hirth 3701 engine, driving a four-bladed Warp Drive composite pusher propeller.

According to the aircraft logbook, on January 14, 2008, the airplane underwent a condition inspection by a certificated airframe and powerplant mechanic with inspector authorization, "for the purpose of LSA [light sport aircraft] Conversion from 'Ultra-Light'" and was found "in airworthy and serviceable condition acceptable for issuance of an LSA airworthiness certificate." Another logbook entry on that date indicated that the next inspection was due no later than February 1, 2009; however, there were no additional entries noted in the logbook.

A receipt revealed that on February 11, 2008, the owner purchased from the engine distributor, among other items, an engine assembly kit, a gearbox assembly kit, and a used coupler flange (gearbox side).

An FAA Aircraft Bill of Sale revealed that on March 13, 2008, the airplane was sold to a second individual.

Another sales receipt indicated that the second owner sold the airplane to a third individual on November 22, 2008. There was no FAA Aircraft Bill of Sale, nor was there a change of registration noted in the FAA aircraft data base. The third owner stated that he had bought the airplane as parts from the widow of the second owner.

According to an associate of the third owner, the associate contacted the Hirth engine distributer at Sun 'n Fun in April 2009, because the engine had a compression problem with one or two of the cylinders. The engine distributor then took the engine to his facility for warranty repair.

A receipt, dated July 7, 2009, indicated that the third owner and the associate purchased from the engine distributor, among other items, a used 3.33 ratio gear set with installation kit, a large prop shaft seal, a prop shaft bearing, and a top end gasket set.

The third owner and the associate recalled that the engine was returned to the owner's place of work in a shipping container, and was subsequently installed on the airplane by a group of individuals.

According to the engine distributor, the engine would have been shipped with the gearbox in the up position, as otherwise it would not fit in a shipping container. The gearbox and adapter plate would have needed to be rotated 180 degrees, to the "hanging" position, to put the thrust line below the engine.

A sales receipt, dated August 17, 2009, indicated that the third owner sold the airplane to the accident pilot. The third owner noted on the sales receipt, in part, "I sell this aircraft in parts, not flyable at present time," and, "I am selling these aircraft parts to [the accident pilot]." The FAA Aircraft Bill of Sale listed the second owner as the seller.

According to the pilot's wife, the airplane was flyable prior to the sale, having seen it fly the previous weekend. However, the third owner, who was also a certificated flight instructor (CFI), stated that it was not flying when sold, and that he gave the accident pilot flight training in another airplane because the accident airplane was not airworthy at the time.

According to the county sheriff's report, the third owner also stated that the accident pilot had kept the airplane at his facility, that it was not flyable and needed repairs, and that the pilot was recently asked to move it to another location. The accident pilot was in the process of finding another place, and the third owner offered to relocate it with his trailer, but the accident pilot had planned to fly it to the new location. The third owner also noted that the accident pilot had been working on the airplane, as well as flying it recently.

The third owner of the airplane also stated in a telephone interview that some time prior to the accident, he had seen that the propeller gearbox retaining bolts were loose, and advised the accident pilot that they needed to be tightened. The third owner later saw the accident pilot attempting to retorque the bolts without torque wrench, and advised him to buy one, which he subsequently did. The torque settings used could not be determined.

According to the manufacturer of the airframe kit, the accident pilot called him on the Wednesday [September 2, 2009] before the accident and stated that the gearbox had been loose, but that he had cleaned and retorqued the bolts.

The engine distributor stated that he had never spoken to the accident pilot.

- Engine/Gearbox Information -

Parts diagrams revealed that aft of the engine there was an estimated 3-inch-deep gearbox adapter plate, attached to the engine case by four 10 mm studs with retaining nuts. Aft of the adapter plate was the gearbox, held to the adapter plate by ten 6 mm bolts. Per the engine distributor, the bolts should have been secured with a threadlocker substance, normally Loctite 242 "Blue" and torqued to 86 inch-pounds.

Within the adapter plate, there was a cylindrical area that housed the output end of the engine drive shaft. The drive shaft was connected to a steel coupler with a three-pronged flange. Aft of the coupler flange was an approximately-circular rubber damper, and aft of that was another coupler flange, which in turn, connected to the gearbox entry shaft.

The rubber damper had six holes located circumferentially toward the outer edge. Three of the holes would have normally contained 10 mm bolts that screwed forward, into the engine-side coupler flange, while the three other holes would have normally have 10 mm bolts that screwed aft, into the gearbox-side coupler flange.

According to the engine distributor, the attaching bolts should have been screwed completely through and slightly beyond the threaded holes in the coupler flanges. The distributor also noted that those bolts should also have been coated with a threadlocker substance, normally Loctite 242 "Blue" to help maintain bolt torque.

PERSONNEL INFORMATION

The pilot, age 26, held a private pilot's certificate with an airplane single engine land rating. Logbook excerpts did not contain the pilot's total flight time; however, on his latest FAA second class medical certificate application, dated July 21, 2009, the pilot indicated 250 hours of total flight time.

The pilot's logbook also indicated that he had flown the accident airplane three times from/to Lake Seminole before the accident flight: a 1.0-hour flight with six water takeoffs and landings on Saturday, August 29, 2009; a 0.5-hour flight with one takeoff and landing on Monday, August 31, 2009; and a 0.8-hour flight with six takeoffs and landings on Saturday, September 4, 2009.

The pilot's logbook also indicated that the third owner provided the pilot with flight training in an airplane other than the accident airplane on August 24, and 28, 2009. It also indicated that the accident pilot received additional training by another CFI in a third airplane on September 1 and 3, 2009.

WRECKAGE AND IMPACT INFORMATION

According to the sheriff's report, the wreckage was located in the Intercoastal Waterway, in Boca Ciega Bay, near channel marker #8, in the vicinity of 27 degrees 47.598 minutes north latitude, 082 degrees, 46.762 minutes west longitude. The pilot/owner was found in the left seat.

From photographs, the airplane came to rest mostly submerg...

Data Source

Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# ERA09LA502