Anchorage-Ted Stevens Intl

On june 2, 1990, at 09:37 Alaskan daylight time, Markair, Inc., flight 3087, a Boeing 737-2X6C, registered in the us as N670MA, crashed about 7.5 miles short of runway 14, Unalakleet, Alaska, while executing a localizer approach to that runway. The flight originated at 0828 at Anchorage International Airport, Anchorage, Alaska. Instrument meteorological conditions existed at the time, and the flight was on an IFR flight plan. The captain, the first officer, and a flight attendant sustained minor injuries. Another flight attendant sustained serious injuries. There were no passengers on board, and the aircraft was destroyed. The flight was operated under far part 121.

The on-demand-charter flight was to originally pickup passengers and cargo but a landing gear problem forced another airplane with a mechanic to be dispatched. The other airplane returned with the passengers and the accident airplane was repaired by the mechanic and departed at a later time with the cargo on board. The airplane was not on a flight plan. Instrument meteorological conditions prevailed from 7,000 feet msl to 12,500 feet msl as reported by the other company airplane. The aircraft was found on the side of Mt Torbert at the 10,570 foot level. The pilot-in-command was found in the right pilot seat with a non-aviation related book in his lap. The mechanic was found in the left pilot seat with a world aeronautical chart, cd-11 open on his lap. The mechanic held a commercial pilots certificate but no instrument rating. The investigation revealed weaknesses in company operations.

The pilot had just departed the runway when he reported to the flight service station that he had engine problems. The aircraft was observed by witnesses to be about 300 feet on a descending downwind. The pilot stated that he was circling for runway 01. Surviving passengers described the engines as running rough and uneven. The investigation revealed that the aircraft's weight was more than the pilot had calculated and the CofG was 3.4 inches further aft than was calculated. However, the weight and CofG were within limits. Examination of the engine disclosed that the right engine had an extensive cylinder head crack, a partially disconnected intake pipe, and was capable of producing 55% of rated power. The left engine had seven severely worn cam lobes. The rudder trim was deflected full left at impact. The evidence indicated that the pilot had retarded the throttle for the left engine and was using only the right engine to sustain flight. Exam of company checklist usage revealed several different improper versions. The pilot and five passengers were killed. Two others passengers and two people on the ground were injured.

During arrival in heavy traffic, Reeve flight 726 (Boeing 727) and Wilburs flight 304 (Cessna 402B, N969JW) received radar advisories for visual approaches to runways 06L and 06R, respectively. Subsequently, both flights were cleared to land. At 1555:04, the local tower controller transmitted that the wind at the approach end of runway 06R was from 340° at 9 knots and the midfield wind was 330° at 7 knots. At approximately 1557, flight 726 landed on runway 06L. Approximately 69 seconds later, as flight 304 was crossing the threshold (thr) of runway 06R at about 100 feet agl, the aircraft encountered wake turbulences (w/t) and rolled sharply to the right, byd 90°. The pilot corrected with aileron and power, but the aircraft lost altitude and hit the ground before recovery. The wind during the 1601 weather observation was 020° at 5 kts. Runway centerlines were 700 feet apart, threshold of runway 06L was 4,600 feet byd the threshold of runway 06R. The approach control did not advise either flight of the other's position, nor did the tower controller give a w/t advisory to flight 304. Calculations showed vortices could have drifted from runway 06L to runway 06R in as little as 28 seconds. FAA handbook addressed w/t advisory for parallel runway options with less than 2,500 feet separation, but did not address offset thresholds. All five occupants were injured.

The mechanic in charge of taxiing the Boeing 727 allowed an unauthorized avionics technician to occupy the pilot seat. They inadvertently deactivated the brake pressurization system and struck a passenger jetway at the terminal gate. An ensuing fire destroyed the airplane and a company ground vehicle and extensively damaged the jetway. The terminal gate was also damaged. A total of 11 persons were injured.

The airplane was destabilized by a slight vertical air movement on approach. The pilot touched the airplane down short of the runway proper, collapsing the landing gear before sliding off the strip into adjacent tundra. All five occupants escaped uninjured.

During arrival to pick up a medevac patient, the flight was cleared for an LDA-1 runway 08 approach via the Asort transition. Thus, the pilot should have continued southeast on J-541 toward the SSR vortac and intercepted the localizer (loc) at Asort; then track inbound on the loc (062°), using I-JDL frequency 109.9 MHz (frequency for loc and co-located DME). After Asort, minimum altitude was 6,500 feet to Dibol intersection, 5,100 feet to Lynns intersection and 3,400 feet to the faf at Barlo intersection. DME from I-JDL to the intersections was: 18.2, 13.5 and 8 miles. DME from SSR (south of loc track) to the intersections was 11.2, 12.7 and approximately 16 miles. Flight reported Asort inbound while descending thru approximately 9,500 feet. Last radio call was 30 seconds later while descending thru 8,200 feet, 14 miles west of Dibol. Approximately 4 miles west of Dibol, aircraft impacted mountain side at 3,500 feet msl. No preimpact mechanical malfunction was found. There was evidence that both nav's were tuned to 109.9 MHz, but DME control head was inadvertently left in 'hold' position (locking DME to SSR rather than I-JDLl) and crew began a premature descent. Juneau weather was in part: 600 feet scattered, 3,000 feet overcast, 7 miles visibility. Pilot-in-command was currently flying both Learjet and DHC-7. All four occupants, two pilots and two doctors, were killed.

During a night arrival, the flight was on an instrument approach to the Gulkana Airport when radio contact with the aircraft was lost. A search was initiated and the wreckage was found 7.4 miles north of the terminal VOR on the 330° radial. The inbound course for the VOR runway 14 approach was on the 315° radial. An on-scene exam revealed the aircraft was tracking inbound when it collided with trees, crashed and burned about 2.4 miles before reaching the final approach fix. Both engines were operating during impact and both had ingested considerable tree material. No preimpact mechanical failure was evident. The captain and 1st officer were currently responsible for flying both the Learjet and DHC-7 aircraft. This was the captain's 1st day of work after returning from a vacation trip to Hawaii (approximately 1-1/2 weeks). The 1st officer had an adequate period for crew rest prior to reporting for work; however, he had previously been working a varied schedule. The operator repeatedly shifted pilots from 14 cfr 135 rest/duty requirements to those of 14 cfr 121. All three occupants were killed.

During arrival, the crew of NP flight 1802 contacted the company weather observer at Soldotna who advised the weather was: wind calm, ceiling 600 to 800 feet, visibility 8 to 10 miles, no precipitations. They made an NDB approach, but missed the approach and requested another approach. Approximately one minute later, the crew reported the aircraft had accumulated a heavy load of ice. They could have diverted nearby to Kenai for an ILS approach, but elected to make a VOR approach back to Soldotna. While being vectored, they made two more checks with the weather observer who advised the weather had deteriorated to below minimums and recommended diverting, but the crew did not acknowledge. Subsequently, the aircraft collided with trees on high terrain approximately 1.5 mile southeast of the airport. There was evidence the aircraft was circling when it crashed. Circling was not authorized south of runway 07/25. Investigations revealed recurring problems with the anti-ice system, its 'single' mode was inoperative, two de-ice boots were missing from prop blades. Weather station listed only one lighted marker (1/4 mile away) for visibility reference; minimum landing visibility was one mile; ceilometer was inoperative. No FAA inspection of weather station in 2 years. Icing forecasted. All nine occupants were killed.

At 0630 akdt the pilot obtained a weather briefing for the flight which forecast VFR with occasional marginal conditions along the route of flight. At 0704, the pilot obtained an updated briefing at which time the destination of Cantwell was reported IFR. At 0731 akdt, the aircraft departed Anchorage International on a company VFR flight. No further communication took place with the aircraft. The aircraft did not reach Cantwell. An extensive search revealed no trace of the aircraft or its occupants.