19990524030949A

(.19) On may 24, 1999, about 1055 eastern daylight time, a Gulfstream American 690C, N840V, was substantially damaged as the left main landing gear collapsed during landing rollout at the Ingalls airport (hsp), Hot Springs, Virginia. The certificated commercial pilot and the two passengers were not injured. Visual meteorological conditions prevailed and an instrument flight rules (IFR) flight plan was filed for the business flight conducted under 14 CFR part 91. The flight originated from the blue grass airport (lex), lexington, Kentucky, about 0945. The pilot reported that the en route portion of the flight was uneventful. He stated that as they approached hsp, the controller descended them to 6,000 feet MSL. Prior to reaching the assigned altitude, the pilot recalled that they had descended out of the clouds, and he spotted the airport. He canceled the IFR clearnace, requested airport advisories, and entered the airport traffic pattern on a left base leg for runway 24. The winds were recorded by the automated weather observing system as 280 degrees magnetic at 26 knots gusting to 31 knots. The pilot stated that it was turbulent as they crossed over the mountain ridges, and he increased his approach airspeed by 5 knots to 105 knots due to the winds. The pilot recalled a "normal touch down, not particulary hard, within the first third of the runway and on the main landing gear." He remembered that the left main landing gear touched down and the airplane rolled about 100 feet, when the left main landing gear collapsed. The airplane skidded to the left and came to rest in an upright position partially off the runway. On my 25, 1999, federal aviation administration inspector examined the airplane and the markings on the runway. By the time the inspector arrived, the airplane was moved off the runway to a hangar apron. The examination revealed that the left main landing gear inboard extension/retraction cylinder clevis and fractured approximately 1 1/8 inches below the attaching bolt hole. A crack at the center of the upper drag brace was found in the webbing where the landing gear door actuating mechanism attaches. The inspector recorded the skid makrs and scarring that remained on the runway. According to statemnts by witnesses and the skid marks left by the airplane, it touched down on the left main landing gear, left of runway centerline, approximately 3,100 feet down the 5,601 foot long runway. The witnesses claimed that this was when they saw the left main landing gear fold. The airplane bounced, touched down on the right this was when they saw the left main landing gear fold. The airplane bounced, touched down on the right main landing gear about 200 feet further down the runway, and then settled on the left propeller and lower fuselage at the 2,000 feet remaining marker. The airplane skidded 1,100 feet down the runway, and came to rest just past the 1,000 foot marker. The fractured clevis and the upper drag brace were removed from the airplane and sent to materials laboratory at the national transportation safety board for further examinaiton. (.4)the airplane was landing in turbulent wind conditions, at a 3,792-foot elevation airport, with winds from 40 degrees to the right, at 26, gusting to 31 knots. The airplane touched down left of runway centerline, approximately 3,100 feet from the beginning of the 5,601-foot runway. The left main landing gear folded, and the airplane bounced. It then touched down on the right main landing gear, about 200 feet further down the runway. It then settled on the left propeller and fuselage about the 2,000 feet-remaining marker, and skidded an additional 1,100 feet. Post-flight examination revealed that the left main landing gear inboard retract cylinder clevis was fractured approximately 1 1/8 inches below the attaching bolt hole. Additionally, a crack at the center of the upper drag brace was found in the webbing where the landing gear door actuating mechanism attached. Laboratory examination of the fracture in the retract cylinder clevis revealed features typical of a bending overstress separation. Laboratory examination of the upper drag brace crack revealed small fatigue crack regions on both sides of a manufactured hole, with no evidence of preexisting mechanical damage, o r other defects in the hole. Remaining portions of the crack in the upper drag brace were consistent with overstress. (-23)on may 24, 1999, N840V, a GA-690-C Gulfstream turbo commander, serial number 11727, departed lexington, KY with an intended destination of Hot Springs, VA. Upon landing at hsp 10:55 local time, the left landign gear collapsed damaging the left propeller, engine and left lower fuselage. The aircraft touched down on the left landing gear, left of runway 24 center line approximately 3100 feet down the runway. The aircraft bounced, touched down on the right gear approximately 200 feet further down the runway, then settled on the left propeller and left lower fuselage at the 200 feet remaining marker. The aircraft skidded 1100 feet further down runway 24 coming to rest just past the 1000 foot marker off onto the grass. No one was injuried.