N832BE

On February 20, 1996, at 2158 mountain standard time, a British Aerospace Avro 146-RJ70A, N832BE, registered to First Security Bank of Utah N.A., and operated by Business Express Inc., as flight 6983, scheduled passenger service under Title 14 CFR Part 121, was undamaged when it overran the runway while landing at Rifle, Colorado. The 24 passengers, and the 4 crew members were not injured. Visual meteorological conditions prevailed at the time, and an IFR flight plan was filed. The flight originated at Minneapolis, Minnesota, at approximately 1900.

The following is based on a telephone interview with the flight crew and their written statements. The airplane had been en route to Aspen, Colorado, but diverted to Rifle due to adverse weather at Aspen. Although Grand Junction, Colorado, was the filed alternate, they elected to proceed to Rifle because it was closer and the passengers could be driven back to Aspen with minimum inconvenience. The current Rifle weather was obtained (calm wind), but the crew did not request precipitation, runway condition, or braking action reports, nor were they offered either by the airport or the company's dispatch office.

The runway was sighted from a distance of 3 miles, and descent from MDA (7,200 feet msl) was begun prior to reaching MAP (1.6 DME) "because it is a very tight approach" (airport elevation is 5,544 feet msl). The first officer flew what he described as a stabilized LOC/DME-A approach to runway 26, using a Vref speed of 115 knots (+5 knots). The airplane crossed the threshold "on target" (airspeed) and touched down approximately 2,500 feet beyond. He deployed the spoilers but "deceleration did not feel normal...the airplane was not slowing...it felt like we were hydroplaning." He checked both yellow and green brake systems, and they were normal. The captain took control and applied maximum braking. Approximately 2,000 feet from the runway end, the captain shut down #1 and #4 engines to reduce residual thrust and aid in the deceleration. The airplane overran the end of the runway and came to a stop 300 feet beyond.

Post-incident examination by the flight crew disclosed the presence of approximately one inch of slush on the runway. While examining the condition of the runway, the captain asked the driver of the truck they were riding to apply the brakes, the truck slid.

The airport manager reported that he witnessed the landing. In a written statement he wrote, "It appeared that the aircraft touched down between the windsock and the ASOS antenna, approximately 4,600 (feet beyond) of runway 26 threshold" (this observation was corroborated by data retrieved from the airplane's global positioning system and digital flight data recorder). The airport manager added, "At 0510Z (2210 MST), a Tapley braking test was performed done on the runway in various locations from A3 taxiway west. Braking tests reported 60-65 value on the Tapley system, indicating that braking action was good." The airport manager further stated that "the runway appeared to be only wet with no build-up of slush or snow."

According to the Digital Flight Data Recorder (DFDR) Study conducted by NTSB's Office of Research and Engineering, "the airplane, while on approach, pitched down 15 degrees about 20 seconds before touchdown. Touchdown occurs at DFDR Subframe Reference Number 4145 at a ground speed of 138 knots. It appears that the nose wheel touched down at the same time or even slightly before the main right and left gear. Indications that the airplane is leaving the runway occur at Subframe Reference Number 4165 and the airplane comes to a complete stop at subframe 4178. Integration of the aircraft's ground speed indicates that it traveled approximately 3,400 feet from the time that it first touched down to the time that it came to a complete stop." According to Attachment III, the indicated airspeed at touchdown was 119 knots. According to the DFDR Factual Report, Attachment I, the wind was from 098 at 6 knots.

According to the manufacturer's flight safety manager, contaminated runway charts are found in the winter operations section of the airplane flight manual (AFM). The charts only go up to 2,000 feet msl and are not valid if there is a tailwind or if the runway slopes downhill. For wet runways, the ground roll is increased by 15 percent. DFDR data shows the nose wheel touched down, then the recording ended. He stated that if the nose wheel is off the ground (or no weight on the nose wheel), or if the nose wheel is canted more than 20 degrees, data will not be recorded.

According to NOAA's instrument approach chart, runway 26 has a 1.2% downhill gradient. According to the AFM, landings on "a very slippery surface having a braking coefficient of friction of 0.05...are not permitted on a downhill runway unless the downhill slope is less than 0.5% and there is no tailwind component."