NTSB CAROL · Event
Event CHI01FA084
Aircraft involved
Probable cause & findings
The flightcrew not lowering the landing gear and/or verifying the landing gear position as required by three separate checklists, which resulted in an inadvertent gear-up landing. A factor to the accident was the flightcrew not complying with the required minimum equipment list placard that prohibited the silencing of the landing gear warning horn.
Factual narrative
HISTORY OF FLIGHT
On February 10, 2001, at 1653 central standard time, a Beech 1900D, N97UX, owned and operated by Great Lakes Aviation, sustained substantial damage during a gear-up landing on runway 4R (8,071 feet by 150 feet, dry/asphalt) at the Chicago O'Hare International Airport, Chicago, Illinois. Visual meteorological conditions prevailed at the time of the accident. The flight was operating under the provisions of 14 CFR Part 121 as Great Lakes Flight 6798 and was on an active instrument flight plan. The captain and first officer (FO) reported no injuries. Eight passengers were released from the accident scene without treatment and seven passengers were transported to local area hospitals for evaluation and treatment of minor injuries. The flight originated at the Capital Airport, Springfield, Illinois at 1605. According to the captain, the crew had switched airplanes in Springfield, Illinois, in order to reposition the accident airplane to a maintenance facility in Spencer, Iowa. The captain reported that there were four maintenance discrepancies that were listed as Minimum Equipment List (MEL) items for the airplane. The MEL items were: Flap System inoperative, Ground Proximity Warning System (GPWS) Modes 1-4 inoperative, Altitude Function of the number two transponder inoperative, and Cockpit/Instrument Lights inoperative on the icing-panel. The captain reported that the crew preformed a preflight inspection of the airplane and a systems-check during an operational run-up. The captain determined the airplane to be in an airworthy condition. The captain reported that the crew used the "Abnormal Procedures: Flaps Up Landing Checklist" due to the flap system being inoperative. The captain stated that he had called for the checklist and that the FO verbally went through the checklist referencing a hard copy of the checklist. The captain stated that when on short final he called for the Final Checklist and the FO verbally went through the checklist. The captain reported that they crossed the runway threshold at 135 knots and were using 131 knots as the reference speed for the landing. The captain stated that he transitioned the airplane for landing, flared, and then the he heard a bang, loud scratching noises, and the airplane began to vibrate. The captain stated that he pushed the nose down, and retained aircraft directional control with rudder pedal inputs. The captain reported, "During the attempted landing the F.O. [first officer] stated that the gear might have collapsed, that is when I notice that the gear was in the UP position." The captain stated, "After the airplane was on the ground and after the F.O. stated that the gear might have collapsed ... I did notice that the gear handle was in the up position. During that time, I do not recall whether the red gear handle light was illuminated or not." The captain reported, "There was no warning of gear unsafe, GPWS disabled, and I did not recall the gear horn go off." The FO stated that during the approach and landing, "No gear horn sounded nor did we ever think the landing gear were not down." The FO reported that, "... A nonstandard note was affixed near the gear handle warning not to cancel the gear warning horn. Since it was not officially documented as an MEL item, its validity was questionable." Written crew statements and summaries of the crewmember interviews are appended to this factual report. The last six minutes of the cockpit voice recorder (CVR) were transcribed as follows: 1647:59 (Captain) Ok. and uh, lets go with the flaps up landing checklist. 1648:03 (FO) Standby. 1648:12 (FO) Flaps up landing checklist... approach speed... one thirty one 1648:16 (Captain) Ok. 1648:16 (FO) That's confirmed... pressurization... checked. 1648:21 (Captain) Yeah it's-. 1648:24 (FO) We're good. 1648:26 (FO) Autofeather switch to arm. GPWS flap override switch, push to activate... surface de-ice cycle as required. Negative required. Landing gear, will go to down, lights will be as required. When landing is assured, yaw damp off, power levers to idle, propellers full forward. 1648:47 (Captain) Bring my power back to fifteen hundred. 1648:53 (Captain) Thank you. 1649:00 (FO) After touchdown, power levers lift and select ground fine. Brakes, as required, to achieve stopping performance. All set? 1649:17 (FO) All set? 1649:18 (Captain) All set. 1649:19 (FO) Ok. I'll put the uh props full forward, you wanna call for that, or you want me to do it. 1649:23 (Captain) Yeah I'll - I'll say short final, props full forward. 1649:25 (FO) Ok. All right. All set. 1649:27 (Approach) Lakes Air seven ninety eight maintain speed one eight zero knots or greater till REKKS, tower at REKKS is twenty seventy five. 1649:33 (Captain) One eighty or greater, tower at REKKS one twenty seventy five Lakes Air seven ninety eight. 1649:38 (Captain) Need to get back here. One eighty to REKKS or greater and ta-tower at REKKS twenty seventy five. 1649:45 (Captain) You- 1649:45 (FO) Do I need to answer? 1649:46 (Captain) I already, I got it. 1649:50 (Captain) All right... where is REKKS? 1649:56 (FO) Uhh six... even... four miles to REKKS. 1650:00 (Captain) All right. 1650:37 (Captain) And... bring me to a thousand please. 1650:42 (Captain) Thank you. 1650:58 (Captain) And there's REKKS coming up, lets go five hundred. 1651:04 (Captain) Thank you. 1651:15 (FO) O'Hare tower Lakes Air seven niner eight, REKKS inbound. 1651:20 (Tower) Lakes Air seven ninety eight O'Hare tower, runway four right cleared to land, wind three one zero at eight. 1651:26 (FO) Roger the winds. Cleared to land Lakes Air seven niner eight. 1651:28 (FO) You are cleared to land captain. 1651:30 (Captain) Thank you. 1651:33 (FO) Three zero zero at eight. 1651:42 (FO) Everybody's down in back the aisle's clear. 1651:56 (Tower) Eagle one fifty all the way down to the end, with a left turn off on delta, ground point nine on delta. 1652:00 (Eagle 150) Point nine on delta we'll see ya, Eagle one fifty. 1652:03 (FO) Aircraft on the runway. 1652:10 (Captain) No delay freaking #. 1652:14 (GPWS) Five hundred. [at an extremely low volume on both the Captain's and First Officer's CVR channels] 1652:16 (FO) Still on the runway, is he taking off? 1652:17 (Captain) Its Ameri- its Eagle. 1652:20 (FO) Is he landing? 1652:23 (Captain) No de-[sound similar to interruption in recording due to tape splice] # do you know what that means? 1652:24 (FO) I got him turning I got him turning. 1652:26 (Captain) [sound of laughter] Lets go props full forward, final check. 1652:30 [sound similar to change in prop speed] 1652:31 (FO) Woah. That's normal. [sound of laughter] 1652:36 (GPWS) (too low), gear. [appears to repeat until impact, at an extremely low volume on both the captain's and FO's CVR channels] 1652:36 (FO) [sound of laughter] I'm so used to (pushing). OK he's clear. 1652:44 (FO) All right, Ref and uh... Ref. 1652:50 (FO) There we go, Ref and ten... Ref. 1653:00 [sound similar to impact] 1653:01 [sound similar to CVR power interruption] 1653:02 [sound similar to landing gear warning horns begins and continues to end of recording] 1653:02 (Captain) Gear down look at the # gear oh #. 1653:04 (FO) Emergency emergency emergency. 1653:07 (FO) Ok everybody stay seated stay seated... stay seated 1653:12 (FO) Stay seated shut down, shut it down. 1653:17 (FO) Emergency emergency Lakes Air seven ninety eight. The gear's failed. 1653:18 [sound similar to stall warning horn begins and continues to end of recording] The landing gear unsafe warning horn did not sound during the entire recorded portion of the accident flight. The entire CVR transcript is appended to this factual report.
PERSONNEL INFORMATION
The captain was the holder of an airline transport pilot certificate with an airplane multi-engine land rating. The captain was also held a commercial pilot certificate with an airplane single engine land rating. The captain was type rated for the Beechcraft 1900 aircraft. The captain's last medical examination was conducted on January 26, 2001, and he was issued a first-class medical certificate with the limitation, "Must wear corrective lenses." The captain was reported to have a total flight time of 2,450 hours, of which 1,060 hours were in multi-engine airplanes and 1,388 hours were in single engine airplanes. The captain was reported to have flown 600 hours in the Beechcraft 1900, of which 580 were as pilot-in-command. The captain was reported to have flown 302 hours in the last 90 days, 97 hours in the last 30 days, and 4.2 hours in the last 24 hours. The captain's last qualification checkride was satisfactorily completed in a Beechcraft 1900 on January 28, 2001. The FO was the holder of a commercial pilot certificate with airplane single-engine land, airplane multiengine land, and instrument airplane ratings. The FO's last medical examination was conducted on March 13, 2000, and he was issued a first-class medical certificate with the limitation, "Must wear corrective lenses." The FO was reported to have a total flight time of 1,449 hours, of which 1,337 were in multi-engine airplanes and 112 hours were in single engine airplanes. The FO was reported to have flown 191 hours in the Beechcraft 1900, all of which were as second-in-command. The FO was reported to have flown 138 hours in the last 90 days, 83 hours in the last 30 days, and 4.2 hours in the last 24 hours.
AIRCRAFT INFORMATION
The aircraft was a Beech 1900D, serial number UE-97. The Beech 1900D is a low-wing monoplane of all-metal construction. The Beech 1900D has fully cantilevered wings, a T-tail empennage, and is powered by two 1,279 horsepower Pratt & Whitney PT6A-67D engines. The engines drive two four-bladed propellers, which are constant speed, full feathering, and reversing. The accident airplane was configured to accommodate a crew of two and nineteen passengers. The Beech 1900D has a certified maximum takeoff weight of 16,950 lbs and a maximum zero fuel weight of 15,000 lbs. The accident airplane was maintained by compliance with a FAA approved continuous airworthiness program and the last inspection was performed on February 5, 2001. The airframe had accumulated a total time of 16,997.0 hours at the time of the accident.
METEOROLOGICAL INFORMATION
A weather observation station located on the Chicago O'Hare International Airport recorded the weather approximately three minutes after the accident as: Observation Time: 1656 Wind: 300 degrees magnetic at 7 knots Visibility: 10 statute miles Sky Condition: Sky Clear Temperature: -08 degrees centigrade Dew Point: -13 degrees centigrade Pressure: 30.49 inches of mercury
COMMUNICATIONS
A partial transcript that covers the Chicago TRACON Approach Control position for the time period of 1636 to 1653 is appended to this factual report. A full transcript that covers the O'Hare ATCT South Local Control position for the time period of 1644 to 1656 is appended to this factual report.
FLIGHT RECORDERS
The solid state flight data recorder (FDR), Fairchild model F1000, serial number 01125, was removed from the accident aircraft and sent to the National Transportation Safety Board's (NTSB) laboratory in Washington, D.C., for readout and evaluation. The Solid State Flight Data Recorder Factual Report is appended to this factual report. The magnetic tape cockpit voice recorder (CVR), Fairchild model A100A, serial number 26380, was removed from the accident aircraft and sent to the NTSB's laboratory in Washington, D.C., for readout and evaluation. A CVR committee convened on February 22, 2001, and a transcription of the CVR was generated. The CVR Specialist's Factual Report of Investigation is appended to this factual report.
WRECKAGE AND IMPACT INFORMATION
The National Transportation Safety Board's on-scene investigation began on February 10, 2001. The airplane was located on the runway 4R centerline approximately 5,400 feet from the approach end of the runway. The airplane was resting upright on the wing-mounted engine nacelles and the aft portion of the fuselage. The landing gear was in the fully retracted position. The landing gear control handle was in the "gear up" position. There was a handwritten placard located under the landing gear control handle that stated, "Do not silence gear warning horn". The flaps were in the fully retracted position and the flap control was in the zero degree position. The circuit breaker for the flap control was pulled and secured with a plastic zip-tie. The airplane was supported by slings and lifted off the ground by a crane. When electrical power was turned on the gear unsafe warning horn sounded, the red landing gear control handle lighting was illuminated, all three gear position lights were red, and the stall warning horn sounded. The landing gear control handle was moved to the "gear down" position the landing gear extended without any anomalies. With the landing gear fully extended all three gear position lights were green, the gear unsafe warning horn did not sound, and the red landing gear control handle lighting was not illuminated. The aircraft was moved to a maintenance hanger and was elevated off the floor by jack-stands. The landing gear warning system was tested and the landing gear was cycled several times without any anomalies. The gear unsafe warning horn sounded and the red landing gear control handle lighting illuminated with the flap control handle positioned in the zero or 17 degree position and either or both power levers were retarded below the preset N1 position. When depressed, the silence button located below the landing gear control handle silenced the gear unsafe warning horn. The landing gear warning system rearmed if either of the power levers were advanced past the preset N1 position or the landing gear was cycled. The gear unsafe warning horn sounded and the red landing gear control handle lighting illuminated when the flap control was set past the 17 degree position, regardless of the position of the power levers, and neither could be canceled unless the landing gear was extended or the flap control was placed in a position of 17 degrees or less. Depressing the silence button did not silence the gear unsafe warning horn when the flap control was set past the 17 degree position.
SURVIVAL ASPECTS
The Survival Factors Specialist Report is appended to this factual report.
TESTS AND RESEARCH
Checklist Items According to the Great Lakes Aviation BE-1900 Flight Standards Manual the normal procedure checklist for "Expanded Landing" is as follows: "The PF (Pilot Flying) will request this checklist at the Final Approach Fix or when the gear is selected down. Flaps - The PNF (Pilot Not Flying) will confirm the desired flap position on command from the PF and check the flap position indicator. Gear - Check landing gear handle down and all 3 green lights illuminated. Final Check Flaps - The PNF will select the desired flap position on command of the PF and monitor flap position indicator. Yaw Damper - Ensure that the Yaw Damp is disengaged no later than the appropriate minimum altitude for the instrument approach being flown or 500 feet on a visual approach. Checklist - On short final, the PNF will ensure the landing gear is extended and call: "Checklist Complete, 3 Green, Cleared to Land"." According to the Great Lakes Aviation BE-1900 Flight Standards Manual the abnormal procedure checklist for "flap up landing" is as follows: "Flaps Up Landing 1. Approach Speed - Confirm 2. Pressurization - Check 3. Autofeather Switch - Arm 4. GPWS Flap Override Switch (if installed) - Push To Activate 5. Flaps - Up 6. Surface Deice - Cycle (as required) Caution - Do not silence the landing gear warning horn, since the flap actuated portion of the landing gear warning system will not be actuated during a flaps-up landing 7. Landing Gear - Down 8. Lights - As Required When Landing Is Assured 9. Yaw Damp - Off 10. Power Levers - Idle 11. Propeller Levers - Full Forward After Touchdown 12. Power Levers - Lift and Select Ground Fine 13. Brakes - As Required (to achieve stopping performance)" According to the chief pilot for Great Lakes Aviation, all normal procedure checklist items from taxi to shutdown are considered mandatory regardless of any additional use of any abnormal checklist. Minimum Equipment List Items There were four maintenance discrepancies that were listed as Minimum Equipment List (MEL) items for the airplane. The MEL items were: Flap System inoperative, Ground Proximity Warning System (GPWS) Modes 1-4 inoperative, Altitude Function of the number two transponder inoperative, and Cockpit/Instrument Lights inoperative on the icing-panel. On February 8, 2001, the flap system was marked inoperative and added as a discrepancy in the aircraft logbook. The captain who entered the discrepancy reported that the flaps did not extend while on approach. The flap system can be inoperative if all of the following criteria are satisfied: (A) Flaps are in the full up position. (B) Performance charts in AFM (Airplane Flight Manual) for no flap takeoff and landing are used. (C) Ensure that a placard is installed near the landing gear warning horn silence button that states, "Do not silence the landing gear warning horn." (D) Visually inspect that the flaps are in the full up position. (E) Pull and band the "IND & Control" circuit breaker. (F) Prior to each departure, determine that the takeoff and landing performance by referencing the Airport Analysis Manual to ensure compliance. The captain of the accident flight did not have the most current inoperative flap system MEL revision prior to the accident flight. The current MEL was revision 05, issued on May 15, 2000, and the captain had revision 04, issued November 26, 1999. For an inoperative flap system the only difference between the two revisions was that the current revision called for a placard "Do not silence the landing gear warning horn" to be installed. The previous revision issued only a cautionary statement, "Do not silence the landing gear warning horn." The FO had the most current MEL revision. Copies of both MEL revisions are appended to this factual report. On February 8, 2001, the GPWS system was marked inoperative and added as a discrepancy in the aircraft logbook. The captain who entered the discrepancy reported that when the GPWS was tested on the ground, "The lights tested normally but no sound came through the headset. He [the FO] asked me if I could hear it, to which I replied no. After testing it several times he told me to press the headset tightly against my ears which I did. Only after pressing the headset tightly against my ears could I barely make out the aural warnings being transmitted through the headset. All other indications tested normally as per the manual. Volume levels were adjusted up and down both on the speaker and headsets but to no avail. Nothing seemed to effect the systems volume either in the headset or speaker system." The GPWS modes 1-4 can be inoperative if all of the following criteria are satisfied: (A) Alternate procedures are established and used. (B) Repairs are made within two flight days. (C) Flight crew will adhere to standard company altitude callouts during the approach.
ADDITIONAL INFORMATION
Subsequent to the accident, Great Lakes Aviation amended their company MEL to prohibit the operation of an aircraft when the flaps and GPWS are both inoperative. According to a Great Lakes Aviation Bulletin, "Please advised that in the interest of safety, effective immediately, Great Lakes will not operate any aircraft with a combination of the Flap System deferred and the Ground Proximity Warning System deferred, unless specifically authorized by a ferry permit. Either one of these items may be deferred in accordance with the approved MEL as a stand-alone item, however the combination of the two will effectively ground the aircraft." The airplane was released to a representative of Great Lakes Aviation on February 11, 2001. Parties to the investigation included the FAA, Great Lakes Aviation, and the International Brotherhood of Teamsters. The crew unintentionally landed the airplane with the landing gear in the fully retracted position. The crew did not lower the landing gear or check the landing gear position as required on the flaps-up landing checklist, the normal landing checklist, and final checklist. According to the cockpit voice recorder (CVR), the landing gear unsafe warning horn did not sound during the entire recorded portion of the accident flight. The minimum equipment list (MEL) requires the installation of a placard that prohibits the silencing of the landing gear warning horn when the flap system is inoperative. The accident airplane had a placard that stated, "Do not silence gear warning horn." No anomalies were found with the landing gear system including the landing gear unsafe warning horn, the red landing gear control handle lighting, and the landing gear position lights. The flap system and ground proximity warning system (GPWS) were inoperative for the accident flight and were listed on the MEL as items that could be inoperative for revenue flight. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_2001_CHI01FA084.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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