NTSB CAROL · Event
Event CHI04LA077
Aircraft involved
Probable cause & findings
The visual lookout not maintained and the procedures not followed by the Push Tug Operator during the pushback. Factors were the parked airplane, the dark night, and the inadequate surveillance of the pushback by airline management.
Factual narrative
On February 24, 2004, about 2110 eastern standard time, a Saab-Scania AB (Saab) Saab 340B, N420XJ, operated by Mesaba Airlines as Flight 3109, was being pushed back for taxi at the Detroit Metropolitan Wayne County Airport (DTW), near Romulus, Michigan, when it struck N364PX, a Saab 340B that was standing. Both airplanes sustained substantial damage. The 2 flight crewmembers, 1 cabin crewmember, and 29 passengers onboard N420XJ were uninjured. N364PX was unoccupied. The scheduled domestic passenger flight was operating under 14 CFR Part 121 on an IFR flight plan. Dark night visual meteorological conditions prevailed at the time of the accident. The flight was destined for Muskegon County Airport (MKG), near Muskegon, Michigan. The operator reported: The pushback was initiated with one wing walker of the right wing. The tug operator than gave the "affirmative" signal to the wing walker, who stopped vehicle traffic on the zipper road, and then the pushback began. The push proceeded as cleared and appeared to be normal to the wing walker until [she] noted that the tug operator did not stop as the main gear reached the taxiway centerline. Realizing that if the aircraft were pushed [too] far back it would collide with an aircraft parked on the ramp the wing walker signaled stop. The push tug operator did not see the stop signal, as he stopped scanning and concentrated his view on the ground looking for another ramp line to stop the aircraft on. The wing walker then began to yell and moved more directly into the tug operator's field of view, transgressing the propeller prohibited area, while displaying the stop signal. Before the tug operator stopped the push back, he had already driven the tail of aircraft N420XJ up and over the nose section of aircraft N364PX. The Push Tug Operator stated: In pushing back this plane I was attempting to do it as I was trained, that is, to [prop] the front wheels on the painted line. I [normally] work on the east side and there is a line [used] for the front wheels. I had not done [a] push back [on] the west side before. While pushing this plane back I started looking for the line as I approached the line my wing walker had stopped walking the [wing] and was off to my left and slightly behind me she says she gave me a stop [signal], but due to her position I could not see her. She ran up to me and told me to stop but it was already [too] late. Excerpts from the airline's Station Operations Manual stated: 5.4 AIRCRAFT PUSHBACK PROCEDURES B. REQUIREMENTS 1. Training Mesaba personnel assigned to pushback an aircraft as the Tug Operator must receive the appropriate training. ... To achieve Pushback Operator certification for Mesaba personnel after attending classroom training, personnel must accomplish three (3) "live" pushback events accompanied by a certified pushback training instructor. ... 2. Pushback Operator The Pushback Operator and the Captain have the overall responsibility for the safe conduct of the pushback operation. 3. Wing Walkers Aircraft shall not be pushbacked in congested areas where clearances are at a minimum (less than 15 feet), unless a Wing Walker (s) is/are stationed as necessary to signal continuously the amount of clearance. It is the Pushback Operator's responsibility to determine the number of Wing Walkers required, based on the situation. ... 7. Checklists Use of the Pushback Operator checklists for Approach to Aircraft and Capture of Aircraft when using the Lektro tow units. Use the Tug Operator's checklist when using the designated towing tug vehicle (see Page 5-7). ... C. COMMUNICATIONS ... The Pushback Operator shall remain alert for signals given by the Wing Walker(s). When Wing Walker(s) is/are used, if visual contact between the Pushback Operator and Wing Walker is lost, stop the pushback. The Pushback Operator must continuously scan for signals and hazards. D. Pushback Operator's Responsibilities Before pushback of an aircraft, the Pushback Operator shall : 1. Determine where the aircraft is to be pushed back to, positioned and route to be taken. 2. Note ALL potential clearance problems to be avoided. 3. Note any existing weather and ramp conditions which could affect how the aircraft might react during pushback. 4. Establish method of communication with Captain. 5. Review with the Captain the route to be taken. ... During pushback of an aircraft, the Pushback Operator shall: ... 16. Begin pushback at low speeds to avoid jerky motions while moving straight ahead before turning. 17. Pushback ONLY when clearance from obstructions (and visual contact with Wing Walker(s), when used) is maintained. ... PUSHBACK OPERATOR CHECKLIST BEFORE PUSHBACK CHECK 1. ASSESS ROUTE, CLEARANCES AND RAMP CONDITIONS. ... On February 24, 2004, a specimen was collected from the Push Tug Operator. The results were "positive DOT urine screen." The test revealed a positive result for cocaine metabolite. 14 CFR Part 121.457, Testing for prohibited drugs, stated: (a) Each certificate holder or operator shall test each of its employees who performs a function listed in Appendix I to this part in accordance with that appendix. (b) No certificate holder or operator may use any contractor to perform a function listed in Appendix I to this part unless that contractor tests each employee performing such a function for the certificate holder or operator in accordance with that appendix. Excerpts from Appendix I stated: This appendix contains the standards and components that must be included in an antidrug program required by this chapter. ... III. Employees Who Must Be Tested. Each person who performs a safety-sensitive function directly or by contract for an employer must be tested pursuant to an FAA-approved antidrug program conducted in accordance with this appendix: A. Flight crewmember duties. B. Flight attendant duties. C. Flight instruction duties. D. Aircraft dispatcher duties. E. Aircraft maintenance or preventive maintenance duties. F. Ground security coordinator duties. G. Aviation screening duties. H. Air traffic control duties. The Push Tug Operator's function is not listed in Appendix I. An airline representative reported that the airline's policy is to accomplish a pre-employment drug test for all safety-sensitive and non safety-sensitive employees. The Push Tug Operator's pre-employment drug test was reported as negative. The airline had a drug policy and an employee assistance program in-place at the time of the accident. An airline representative reported that the supervisor and coordinator for the accident gate area were two gates away and did not directly observe the accident pushback. Subsequent to the accident, the airline revised their Ground Operations Manual. Excerpts from the revised manual stated: 3.1 GENERAL PROCEDURES A. Enforcement Responsibilities 1. Management and Supervisory Personnel It is the responsibility of all management and supervisory personnel to publicize these basic rules of safety and enforce them by not permitting any exceptions other than those outlined in this section. 2. All Employees It is the responsibility of all Mesaba Airlines employees to read and understand these basic ramp procedures as they are paramount to a safe and efficient operation. Safety rules must always be observed to ensure personal protection, as well as to protect co-workers, flight equipment, and ground equipment from injury or damage. Subsequent to the accident, the airline established a policy of random drug testing for all employees as a condition of employment. The Federal Aviation Administration and Mesaba Airlines were parties to the investigation. The scheduled domestic passenger flight was being pushed back for taxi when it struck an unoccupied airplane that was parked on the ramp. Both airplanes sustained substantial damage. The 2 flight crewmembers, 1 cabin crewmember, and 29 passengers were uninjured. Dark night visual meteorological conditions prevailed at the time of the accident. The Push Tug Operator stated, "In pushing back this plane I was attempting to do it as I was trained, that is, to [prop] the front wheels on the painted line. I [normally] work on the east side and there is a line [used] for the front wheels. I had not done [a] push back [on] the west side before. While pushing this plane back I started looking for the line as I approached the line my wing walker had stopped walking the [wing] and was off to my left and slightly behind me she says she gave me a stop [signal], but due to her position I could not see her. She ran up to me and told me to stop but it was already [too] late." Excerpts from the airline's Station Operations Manual stated, "The Pushback Operator and the Captain have the overall responsibility for the safe conduct of the pushback operation. ... The Pushback Operator shall remain alert for signals given by the Wing Walker(s). When Wing Walker(s) is/are used, if visual contact between the Pushback Operator and Wing Walker is lost, stop the pushback. The Pushback Operator must continuously scan for signals and hazards. ... Before pushback of an aircraft, the Pushback Operator shall : 1. Determine where the aircraft is to be pushed back to, positioned and route to be taken. 2. Note ALL potential clearance problems to be avoided. ... 5. Review with the Captain the route to be taken. ... During pushback of an aircraft, the Pushback Operator shall: 17. Pushback ONLY when clearance from obstructions (and visual contact with Wing Walker(s), when used) is maintained. ... PUSHBACK OPERATOR CHECKLIST, BEFORE PUSHBACK CHECK 1. ASSESS ROUTE, CLEARANCES AND RAMP CONDITIONS." The Push Tug Operator tested positive for cocaine metabolite. 14 CFR Part 121 Appendix I stated, "Each person who performs a safety-sensitive function directly or by contract for an employer must be tested pursuant to an FAA-approved antidrug program conducted in accordance with this appendix." The Push Tug Operator was not on the FAA's safety-sensitive list. An airline representative reported that the airline's policy is to accomplish a pre-employment drug test for all safety-sensitive and non safety-sensitive employees. The Push Tug Operator's pre-employment drug test was reported as negative. The airline had a drug policy and an employee assistance program in-place at the time of the accident. An airline representative reported that the supervisor and coordinator for the accident gate area were two gates away and did not directly observe the accident pushback. Subsequent to the accident, the airline established a policy of random drug testing for all employees as a condition of employment. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_2004_CHI04LA077.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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