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Atlas / NTSB / CEN21LA325

NTSB CAROL · Event

Event CEN21LA325

2021-07-18 Longmont, Colorado, United States Airport · LMO Serious 1 aircraft Status: Completed

Registry · N18AR

FAA Aircraft Registry record.

Make / Model

BEECH 35-C33

Year of manufacture

1965 · 56 years old at event

Engine

CONT MOTOR I0-470 SERIES (260 hp)

Seats / Engines

4 seats · 1 engine

Last airworthiness date

19650902

ADS-B equipped

Yes — Mode-S A13E63

Registrant of record

BAS PART SALES LLC

Source: FAA Aircraft Registry (releasable master file).

Aircraft involved

Probable cause & findings

The airplane’s lack of climb performance after takeoff in high density altitude conditions for reasons that could not be determined based on the available evidence.

Factual narrative

On July 18, 2021, about 0850 mountain daylight time, a Beech 35-C33 airplane, N18AR, was substantially damaged when it was involved in an accident near Vance Brand Airport (LMO), Longmont, Colorado. The pilot and passenger sustained serious and minor injuries, respectively. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that the preflight inspection and run-up were normal and that, per the high-density altitude procedures, he leaned the fuel mixture before takeoff from the 4,799-ft-long runway. He rotated at 85 mph and initiated a climb; however, the airspeed and climb rate “did not look normal.” He was not certain that the airplane would clear a house located along the departure path and decided to execute a precautionary landing. He retracted the landing gear and entered a right turn to avoid the house. The airplane touched down and slid to a stop on its belly. The airplane impacted a hayfield and came to rest about 1/3 mile from the departure end of the runway. The fuselage and both wings sustained substantial damage consistent with the impact sequence. Post-recovery airframe and engine examinations did not reveal any anomalies consistent with a loss of engine power. Based on the 0855 weather observation at LMO, the calculated density altitude for the takeoff was 6,804 ft. Airplane performance data indicated that the expected takeoff distance to clear a 50-ft obstacle and the expected initial rate of climb were about 2,900 ft and 780 ft per minute, respectively. The pilot reported previous flight experience at high-density altitude airports that included flight instruction for such operations. The pilot was departing on a personal flight with a density altitude of 6,804 ft. After takeoff, the airplane’s climb rate “did not look normal,” and the pilot was not certain that the airplane would clear a house located along the departure path. He decided to execute a precautionary landing to a hayfield about 1/3 mile from the departure end of the runway. The pilot retracted the landing gear, and the airplane touched down and slid to a stop on its belly. Airplane performance data indicated that the expected initial rate of climb was about 780 ft per minute. Airframe and engine examinations did not reveal any anomalies consistent with an inability to maintain the published rate of climb or to produce rated engine power. Therefore, the investigation was unable to determine the reason for the lack of climb performance. Regardless, the pilot’s decision to execute a precautionary landing under the circumstances was prudent. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12

NTSB Findings

Hierarchical cause / factor breakdown from the FAA bulk avdata database. Each finding tagged C (Cause) or F (Factor).

  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Climb rate-Not attained/maintained
  • Not determined-Not determined-(general)-(general)-Unknown/Not determined

Verbatim from NTSB's published report. Source file NTSB_2021_CEN21LA325.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.