19991014040969A

(-23) While making an approach to the west helicopter landing pad at Los Angeles International Airport, helicopter N16889 experienced a partial loss of engine power. Then the pilot increased collective pitch at approximately 200' AGL to slow the aircraft's descent for landing, the rotor RPM dropped below 90% (with the throttle full open). The pilot turned the helicopter to the left and performed an autoratation, over a terminal building, landing on the ramp area between terminal's 5 and 6. In order to clear the terminal building, the pilot increased collective pitch, allowing the rotor RPM to decay. On short final a twin engine turboprop turned into the landing area. The pilot veered to the right to avoid the turboprop. With rotor RPM being low prior to impact, the aircraft landed extremely hard. After impact, the helicopter made a 180 degree turn and slid approximately 60 feet before coming to a stop. The engine was running at low idle at the scene. All 3 occupants of the aircraft sustained back injuries or varying seriousness. The aircraft was destroyed. (.4) on October 14, 1999, at 1631 hours pacific daylight time, a Bell 206B, N16889, collided with the airport ramp during an attempted landing at the Los Angeles International Airport, Los Angeles, California. The helicopter, operated by tsr helicopters inc., van nuys, California, sustained substantial damage. The commercial pilot and two passengers were seriously injured. The personal flight, conducted under the provisions of 14 CFR part 91, originated at the van nuys airport about 1600, and was en route to the Los Angeles airport to drop off one of the passengers. Visual meteorological conditions prevailed and no flight plan was filed. A federal aviation administration (FAA) inspector from the Los Angeles flight standards district office interviewed the pilot and passengers in the hospital. The pilot stated that he reported his position to the Los Angeles air traffic control tower when he was about 1 mile north of the runway 24 complex. He was given instructions to cross the extended centerline of the parallel runways at 1,500 feet. After crossing the runways, and once abeam the elevated helipad, the pilot made a slight left turn away from the pad to allow for more spacing in the descent. He stated that he had performed that particular approach several times and was familiar with the flight profile and procedure. The pilot reported that to maximize the descent rate, he lowered the collective to flat pitch, and momentarily entered a transient overspeed condition of the N2 turbine; the N2 needle climbed to 103 percent for about 4 seconds. He explained that a transient overspeed in that helicopter allows up to 107 percent RPM overspeed for 15 seconds with torque settings up to 32 percent. The pilot reported that he lowered the nose of the helicopter to stop the N2 increase. The pilot turned right toward the helipad and descended at a rate of about 1,300 feet per minute until he intercepted a standard approach profile. He reported that as he reapplied power and increased collective pitch, the rotor RPM immediately drooped to 90 percent. The low rotor RPM horn and light came on and the pilot fully lowered the collective. He estimated that his altitude at that time was between 100 to 150 feet AGL, and his airspeed was about 60 knots. He declared an emergency to the air traffic control tower and turned left toward an open area between terminals 5 and 6. The pilot realized he might not have sufficient altitude to clear the terminal bu ildings, so he pulled collective pitch, which further decayed the rotor RPM but provided additional lift. As he descended to his intended landing point, a twin-engine turboprop airplane turned into the ramp area and the pilot veered to the right to avoid it. The pilot stated that he fully lowered the collective and realized that he'd have to perform a run-on landing with little or no flare. He pulled all remaining collective pitch before impacting the ground. The helicopter contacted the ground in a tail-low attitude, slid forward approximately 60 feet, and made a 180-degree turn. The right front chin bubble shattered on impact. Both landing gear skids were forced upward through the cabin. The helicopter came to rest on its belly. The pilot attempted to shut the engine off by rolling the throttle past the idle cutoff position but he was not able to manipulate the throttle. He turned off the fuel shutoff valve, generators, and battery. The pilot stated that he had not experienced any problems with the helicopter prior to the accident.