LAX05GA243

The airplane descended into the ground during takeoff-initial climb on a local fire reconnaissance flight. Witnesses reported that airplane became airborne, but was not climbing, and it continued down the runway in a nose-up attitude in ground effect until impacting terrain about 600 feet southeast from the departure end of the runway. The ambient temperature was about 107 degrees Fahrenheit, and the density altitude was calculated at 5,878 feet mean sea level. On scene examination found the flaps in the 30-degree position, which also corresponded to the flap actuator position. The cockpit indicator for the flaps also showed a 30-degree extension. A subsequent bench test of the combined flap/gear selector valve was conducted. During the initial inspection, both the gear selector and the flap selector valves were bent, but otherwise operational. The "stop-pin" on the flap selector lever was missing. There was no leakage of fluid during this test. Examination of both engines revealed no abnormalities, which would prevent normal operations. The aircraft flight manual specifies that the flaps should be set at 1/4 down (10 degrees) for normal takeoff.

1.1 History of flight

On July 21, 2005, about 1707 Pacific daylight time, an Aero Commander 680 FL, N7UP, impacted terrain during takeoff at North Las Vegas Airport (VGT), Las Vegas, Nevada. Commander Northwest LTD was operating the airplane under contract for the United States Department of Agriculture (USDA) - Forest Service under the provisions of 14 CFR Part 91 as a public-use aircraft. The airline transport pilot and one passenger sustained serious injuries; the second passenger sustained minor injuries. The airplane was destroyed. The local fire reconnaissance flight was departing VGT at the time. Visual meteorological conditions prevailed, and a company flight plan had been filed. The primary wreckage was at 36 degrees 12.233 minutes north latitude and 115 degrees 11.289 minutes west longitude.

During takeoff from runway 12R, witnesses reported seeing the airplane airborne but not climbing. The airplane continued down the runway in a nose up attitude and remained in ground effect until impacting terrain about 600 feet southeast from the departure end of runway 12R. The airplane impacted in a 30-degree nose down attitude. During the accident sequence, the airplane rotated about 270 degrees around the vertical axis. The cockpit section of the airplane was destroyed during the accident sequence.

The operator submitted a Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2) on August 9, 2005.

1.5 Personnel information

A review of Federal Aviation Administration (FAA) airman records revealed that the pilot held a commercial certificate with ratings for airplane single engine land and an airline transport pilot certificate with ratings for airplane multiengine land.

The pilot held a second-class medical certificate that was issued on March 11, 2005. It had the limitation that the pilot must possess glasses, which correct for near vision.

According to employment records, the pilot was employed as a pilot by Commander Northwest LTD beginning in March 2005.

Employer records indicated that the pilot had an estimated total flight time of 5,285 hours. He logged 65 hours in the last 90 days, and 58 hours in the last 30 days. He had an estimated 75 hours in this make and model. He was the standby pilot for the accident airplane. He flew the accident airplane for 0.5 hours on July 17, 2005, 6.08 hours on July 19, 2005, and 5.73 hours on July 20, 2006. He completed a biennial flight review on March 15, 2005.

1.6 Aircraft information

The airplane was an Aero Commander 680 FL, N7UP, serial number 134929. A review of the airplane's logbooks revealed an annual inspection dated February 7, 2005, at an airframe total time of 8,659.8 hours, and a Hobbs hour meter reading of 1,783.5. The logbooks had an entry for a 100-hour inspection dated June 30, 2005, at which time the Hobbs hour meter read 2,066.3. The Hobbs hour meter read 2,105.7 at the accident scene. The total time of the airplane at the time of accident was 8,982.0.

The left engine was a Textron Lycoming IO-720-B1BD engine, serial number 1288-54A. The engine had 332.3 hours since the last overhaul, which was accomplished on December 3, 2004. The logbooks had an entry for a 100-hour inspection dated June 30, 2005, and the Hobbs hour meter read 2,066.3.

The right engine was a Textron Lycoming IO-720-B1BD engine, serial number 1211-54A. The engine had 715.5 hours since the last overhaul, which was accomplished on October 27, 2003. The logbooks had an entry for a 100-hour inspection dated June 30, 2005, at which time the Hobbs hour meter read 2,066.3.

On the morning of the accident, maintenance was performed on the left engine due to a hard starting problem. The on-site mechanic reported cleaning the spark plugs and verifying ignition timing. A maintenance test run was performed on the engine with satisfactory results. The aircraft was released for service and scheduled for the accident flight.

Examination of the maintenance and flight department records revealed no unresolved maintenance discrepancies against the airplane prior to departure.

Fueling records at North Las Vegas Air Terminal established that the airplane was last fueled to capacity on July 20, 2005, at 2016, with the addition of 118 gallons of 100 low lead aviation fuel. The aircraft flight manual indicates maximum fuel capacity of 223 gallons.

1.6.4 Aircraft operating weight & balance

A weight and balance form was completed prior to the date of the accident by the pilot. Investigators weighed the baggage post accident. Weight and balance calculations placed the airplane at a takeoff weight of 7,769 pounds. The maximum gross weight for the airplane was 8,000 pounds. The center of gravity (CG) was computed as 209.09 inches. The CG envelope for the computed takeoff weight was between 206 and 218 inches.

1.7 Meteorological information

An aviation routine weather report (METAR) for VGT was issued at 1653. It stated: winds from 170 degrees at 05 knots; visibility 10 miles; skies clear; temperature 42 degrees Celsius; dew point 09 degrees Celsius; altimeter 29.79 inHg. The density altitude was calculated at 5,878 feet mean sea level. The pressure altitude was 2,361 feet.

1.9 Communications

The airplane was in contact with VGT airport traffic control tower (ATCT) on frequency 125.70. After the takeoff clearance, the pilot made no further radio transmissions.

1.10 Airport information

The Airport/Facility Directory, Southwest U. S., indicated that runway 12R was 5,000 feet long with a 300-foot overrun at the departure end, and 75 feet wide. The runway surface was composed of asphalt.

Tower records indicate that the accident occurred at 1707. The Las Vegas Fire Department records indicate that they received notification of the accident at 1708. The first fire department vehicle arrived on scene at 1715.

1.12 Wreckage and impact information

1.12.1 General information

Investigators from the National Transportation Safety Board, FAA, Twin Commander Aircraft LLC, and Textron Lycoming examined the wreckage at the accident scene.

The first identified point of contact (FIPC) was a ground scar. The debris path was along a magnetic bearing of 104 degrees. The FIPC was 100 yards southeast of the departure end of runway 12R. The fuselage came to rest 88 yards southeast of the FIPC.

The representative from Twin Commander identified the debris found at the beginning of the debris field starting from the FIPC as forward fuselage and cockpit structures. Pieces of the left wing tip were found in the middle of the debris field.

1.12.2 Airframe structures

The fuselage came to rest on a heading of 215 degrees magnetic.

The left side of the fuselage was wrinkled along its full length. About 1 foot aft of the inboard left wing flap, there was a vertical length of buckling, which started on the top side and went down to the underside, and was about 5 inches at its deepest point. Underneath the vertical stabilizer on the left side of the fuselage, there was a length of buckling, which started from the underside and went upward and aft about 20 degrees, and was about 2 feet long. Aft of the buckling, the fuselage showed upward crushing angled left. The tail cone was bent to the right.

1.12.2.1 Wings

Left wing

The left forward inboard portion of the wing had no impact damage until the outboard 1/3 of the wing, where it curled upward about 120 degrees past horizontal and was twisted aft. The signatures on the underside of the outboard 1/3 of the wing were crushed and wrinkled along the length and width.

The outboard flap on the left wing was undamaged. The inboard flap showed no impact damage. The left inboard flap was documented trapped against the fuselage in the 30-degree extended position.

Right wing

The right wing was found resting on the ground. It showed wrinkling and buckling startin