# NTSB CHI06LA058: Cessna 560, N391QS, Woodruff, WI, January 5, 2006 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 5, 2006, 08:00 local (14:00 UTC) - Place: Woodruff, WI - Coordinates: 45.935554, -89.74028 - Nearby events: https://openairdocs.org/map.md?lat=45.9356&lon=-89.7403&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 7 uninjured - Status: Completed, report March 26, 2007 - Report: Approved by Office Director - Parties: NetJets Aviation, Cessna, Federal Aviation Administration - NTSB case key (mKey): 63068 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI06LA058 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/63068/pdf - Page: https://openairdocs.org/ntsb/CHI06LA058 ## Probable cause The Captain's failure to maintain adequate airspeed during the landing which resulted in a stall/mush. Factors were the gusty conditions, the snowbank in the safety area next to the runway, and the runway light that the airplane struck. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, landing - weather condition - gusts (contributing factor) - airspeed - not maintained, pilot in command (cause) - stall/mush - encountered, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground - terrain condition - runway - terrain condition - snowbank (contributing factor) - object - airport sign/marker (contributing factor) ## Analysis The airplane, on a non-scheduled domestic passenger flight, sustained substantial damage when the right wing contacted runway 36 during landing. The airplane subsequently departed the runway and impacted a snow bank. The operator stated, "The briefed REF [airspeed at the 50-foot point with flaps in the landing position and landing gear extended] speed was 101 knots. Due to weather conditions the Captain flew the approach at 110 knots. The crew encountered light rime icing descending through 4,500 feet until the time they broke out visually at approximately 2,600 feet. The crew utilized the aircraft boots 3 times on the approach to ensure the aircraft was free of contamination. The crew descended on the PAPI [precision approach path indicator] for runway 36 after breaking out visually. At approximately 55 feet the Captain brought the power levers to idle as normal. All seemed normal until approximately 20 to 30 feet when the aircraft felt as if it lost lift and the right wing dropped. The Captain added power and it took both hands to level the wings. The aircraft impacted the runway with the right wingtip hitting first. The aircraft then bounced back in the air and turned slightly to the right. The aircraft then once again settled to the surface off the right side of the runway." The airplane impacted a runway light. The Captain stated that the stick shaker came on and that he added engine power during the landing. The first officer stated that the airplane's airspeed dropped to REF -4 to -5 knots when the airplane was about 20 feet above ground level. The recorded wind was 350 degrees at 14 gusting to 21 knots. A caution in the airplane's operating manual stated, "IN ICING CONDITIONS, A SMALL AMOUNT OF RESIDUAL ICE WILL FORM ON UNPROTECTED AREAS. THIS IS NORMAL, BUT CAN CAUSE AN INCREASE IN STALL SPEEDS. WHEN ANY AMOUNT OF RESIDUAL ICE IS VISIBLE, THE STALL SPEEDS IN FIGURE 4-7 OF THE AIRPLANE FLIGHT MANUAL INCREASE BY 5 KNOTS. THE VREF/VAPP SPEEDS, LANDING DISTANCES AND THE MAXIMUM LANDING WEIGHT PERMITTED BY BRAKE ENERGY MUST BE CORRECTED IN ACCORDANCE WITH FIGURE 4-32 OF THE AIRPLANE FLIGHT MANUAL." ## Factual narrative HISTORY OF FLIGHT On January 5, 2006, about 0800 central standard time, a Cessna 560, N391QS, operated by NetJets Sales, Inc., sustained substantial damage when the right wing contacted runway 36 during a landing at the Lakeland Airport/Noble F. Lee Memorial Field (ARV), near Minocqua-Woodruff, Wisconsin. The airplane subsequently departed the runway and impacted a snow bank. The non-scheduled domestic passenger flight was operating under 14 Code of Federal Regulations Part 135. Visual meteorological conditions prevailed at the time of the accident. The flight was operating on an activated instrument flight rules flight plan. The pilot, co-pilot, and five passengers were uninjured. The flight originated from the Palwaukee Municipal Airport (PWK), near Wheeling, Illinois about 0723. The operator's accident report, in part, stated: N391QS departed KPWK enroute to KARV with 5 passengers on a part 135 flight. The enroute portion of the flight was without event. The crew verified the weather and landing numbers enroute. In light of a notam for the AWOS [automated surface observing system] wind readout at KARV as being unreliable the crew procured the latest weather from KRHI [Rhinelander-Oneida County Airport, Rhinelander, Wisconsin] enroute to validate the winds and that landing on runway 36 at KARV was suitable. The crew briefed and flew the localizer approach to runway 36 at KARV. The briefed REF speed [airspeed at the 50-foot point with flaps in the landing position and landing gear extended] was 101 knots. Due to weather conditions the Captain flew the approach at 110 knots. The crew encountered light rime icing descending through 4,500 feet until the time they broke out visually at approximately 2,600 feet. The crew utilized the aircraft boots 3 times on the approach to ensure the aircraft was free of contamination. The crew descended on the PAPI [precision approach path indicator] for runway 36 after breaking out visually. At approximately 55 feet the Captain brought the power levers to idle as normal. All seemed normal until approximately 20 to 30 feet when the aircraft felt as if it lost lift and the right wing dropped. The Captain added power and took both hands to level the wings. The aircraft impacted the runway with the right wingtip hitting first. The aircraft then bounced back in the air and turned slightly to the right. The aircraft then once again settled to the surface off the right side of the runway. In an interview, the Captain stated that the stick shaker came on and that he added engine power during the landing. The first officer (FO) stated that the airplane's airspeed dropped to REF -4 to -5 knots when the airplane was about 20 feet above ground level. DAMAGE TO AIRCRAFT The operator reported that the airplane's "nose landing gear wheel assembly and nose landing gear strut fork separated from the aircraft. Right side nose landing gear door separated from aircraft. Damage to radome, fuselage structure aft of nose landing gear well, right wing inboard flap panel and attaching structure, right wing upper and lower surfaces, and right wing tip." OTHER DAMAGE The operator also reported that the airplane "struck and destroyed a runway light marker light." PERSONNEL INFORMATION Captain: The captain held an airline transport pilot (ATP) certificate with an airplane multiengine land rating. He was type-rated for the Cessna 500 airplane. His last medical examination was completed on August 8, 2005, and he was issued a first-class medical certificate without limitations. The operator reported the captain as having accumulated a total flight time of 8,452 hours and 1,792 hours in the same make and model airplane. He flew 131 hours during the last 3 months, 36 hours during the previous 30 days, and 2 hours during the prior 24 hours. First Officer: The FO held an ATP certificate with an airplane multiengine land rating. He was type-rated for the Cessna 500 airplane. His last medical examination was completed on July 7, 2005, and he was issued a first-class medical certificate without limitations. The operator reported the FO as having a total flight time of 3,200 hours, and 72 hours in the same make and model airplane. He flew 69 hours during the last 3 months, 34 hours during the previous 30 days, and 2 hours during the prior 24 hours. AIRCRAFT INFORMATION N391QS was a twin engine Cessna 560, serial number 560-0429. The airplane was configured with eight seats and had a maximum gross weight of 16,300 pounds. The airplane was powered by two Pratt and Whitney Canada engines rated at 3,045 pounds of thrust each. The last approved inspection program maintenance inspection was conducted on December 3, 2005. The airplane had accumulated a total time of 6,276 hours. The airplane's flight control was through conventional cable-operated surfaces. Trimming was provided by aileron, elevator, and rudder tabs. The airplane incorporated hydraulically operated speed brakes and trailing edge flaps. The airplane's operating manual, in part, stated: STALL WARNING - STICK SHAKER Stall warning is achieved by the use of a stick shaker mounted on the forward side of the pilot's control column. An electric motor with rotating weights induces a vibration feel to the control column. The pilot is alerted to impending stall by the vibration of the control column which occurs approximately 8% to 10% above the actual stall speed. Stick shaker activation will occur before stall buffet, except in the clean configuration where they are nearly the same and either could occur first. The stick shaker is energized by inputs from the angle-of-attack system. The test switch located on the pilot's switch panel provides a means of checking the shaker prior to flight. ... Speed control on final should be precise for optimum landing performance and this is best accomplished by establishing VREF airspeed well before crossing the threshold. In gusty wind conditions, it is recommended that one half the gust factor in excess of 5 knots be added to VREF. Approaching within approximately 50 feet of airport elevation, power should be gradually reduced to counter the acceleration induced by ground effect. Wind velocity and direction will dictate the rate at which the throttles are retarded. In very high surface headwind conditions, as an example, it may be necessary to maintain at or near approach power until close to touchdown. With a tailwind, a fairly rapid power reduction may be necessary in the final descent to landing phase for accurate speed control. In ground effect, where induced drag is reduced, leaving approach power on will cause the airplane to float to a longer touchdown than desired. Retarding the throttles gradually in the final descent will normally result in idle thrust being reached just before touchdown. ... CAUTION IN ICING CONDITIONS, A SMALL AMOUNT OF RESIDUAL ICE WILL FORM ON UNPROTECTED AREAS. THIS IS NORMAL, BUT CAN CAUSE AN INCREASE IN STALL SPEEDS. WHEN ANY AMOUNT OF RESIDUAL ICE IS VISIBLE, THE STALL SPEEDS IN FIGURE 4-7 OF THE AIRPLANE FLIGHT MANUAL INCREASE BY 5 KNOTS. THE VREF/VAPP SPEEDS, LANDING DISTANCES AND THE MAXIMUM LANDING WEIGHT PERMITTED BY BRAKE ENERGY MUST BE CORRECTED IN ACCORDANCE WITH FIGURE 4-32 OF THE AIRPLANE FLIGHT MANUAL. METEOROLOGICAL INFORMATION At 0755, the recorded weather at ARV was: Wind 350 degrees at 14 gusting to 21 knots; visibility 10 statute miles; sky condition overcast 1,300 feet above ground level; temperature -3 degrees C; dew point -5 degrees C; altimeter 30.04 inches of mercury. AIDS TO NAVIGATION ARV has a localizer approach to runway 36. The final approach fix, identified as DOUGY, is located 6.5 distance measur ## Aircraft - Registration: N391QS (not matched to a registry record) - Reported make and model: Cessna 560 - Category: Airplane - Serial number: 560-0493 - Airframe hours: 6276 - Engines: Pratt & Whitney Canada JT15D 3045 lbs thrust turbo jet; Pratt & Whitney Canada JT15D 3045 lbs thrust turbo jet - Damage: Substantial damage - Flight: Part 135 - Registered owner: Netjets Sales Inc. - Airworthiness certificate: Standard, Transport - Last inspection: AAIP, December 1, 2005 - Departed: PWK, CHICAGO/PROSPEC, IL - Destination: ARV, Woodruff, WI - Flight plan: IFR - Airport: ARV, Lakeland/Noble F. Lee Memorial, runway 36, 5,150 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; injuries: none; flight instructor, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 1, without waivers/limitations; last flight review October 1, 2005; seat: left; flight hours: 8,452 total, 1,792 in this make and model, 6,000 as pilot in command, 131 in the last 90 days, 36 in the last 30 days, 2 in the last 24 hours - Co-pilot; age 40; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review July 1, 2005; seat: right; flight hours: 3,200 total, 72 in this make and model, 1,700 as pilot in command, 69 in the last 90 days, 34 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 350° at 14 knots, gusting 21 - Visibility: 10 statute miles - Lowest ceiling: 1,300 ft overcast - Temperature: 27 °F, dew point 23 °F - Altimeter: 30.04 inHg - Observed at: ARV ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20060105000829A](https://openairdocs.org/incident/20060105000829A), Jan 5, 2006: Cessna 560CESSNA, Minocqua/Woodru, WI, Substantial damage. (-23) The pilot and copilot both stated that while crossing the runway 36 threshold and after power reduction the wind quit. The stick shaker activated and it… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.