It seemed nothing would go right on March 8, 2017, for the crew of Ameristar Charters Flight 9363, an MD-83 flight from Willow Run Airport (KYIP) in Ypsilanti, Michigan, to Washington Dulles International Airport(KIAD) in Virginia — at least that was the case until the captain’s quick decision-making averted tragedy by aborting the takeoff well after accelerating through V1.
Still, the aircraft ran off the 7,543-ft.-long Runway 23L (including a 200-ft. blast pad) and traveled about 950 ft. across the grassy part of the runway safety area (RSA) before striking the airport perimeter fence and a raised, paved road and finally coming to a stop on the fuselage belly about 1,150 ft. west of the runway end.
The thing that went right is that all 110 passengers and six crewmembers evacuated with only one minor injury suffered by a passenger. Another thing that went right is that the NTSB congratulated the crew on a job well done despite challenges faced by the pilots earlier that morning.
Orthomosaic image of the airplane’s path from the end of Runway 23L to its final location. Credit: NTSB

Ypsilanti was cold and extremely windy that day as it had been for several previous days. The most recent Terminal Aerodrome Forecast (TAF) for KYIP expected sustained wind from 250 deg. at 32 kt. with gusts to 48 kt., visibility greater than 6 mi., and a few clouds at 6,000 ft. AGL. AIRMETs had been issued at 0945 for surface winds greater than 30 kt. and Sigmets called for turbulence below 12,000 ft.
In fact, winds were so strong that morning that the tower controllers evacuated their roost at about 1139 when high wind and gusts from the west caused a power outage at the airport and disabled some of its weather observing equipment. The controllers issued a notification at 1217 advising that the airport had no air traffic control services (referred to as “ATC Zero”). Thus, the airport had become an uncontrolled facility.
Making matters worse, KYIP was a Limited Aviation Weather Reporting Station (LAWRS) facility. When the Automated Surface Observing System (ASOS) lost some of its sensor functions and the LAWRS observer failed to sign off from the ASOS operator interface device (OID), no one provided backup information to supplement the weather data that was missing from the ASOS.
As a result, said NTSB investigators, throughout the day of the accident, the ASOS continued to automatically disseminate Meteorological Terminal Aviation Routine Weather Reports (Metars) that did not contain the AUTO modifier to show they were not being augmented by a weather observer and did not contain complete weather information.
The winds were also whipping around a quarter-mile-long hangar adjacent to the west pad, sending swirling, accelerated gusts around the Ameristar MD-83 that had been parked on the pad for two days. No one knew, nor could they have known, that the high-velocity, ground-level turbulence was beating up the aircraft’s elevators.
The pilots arrived at KYIP at about 1130 on the morning of the accident. The 54-year-old captain held a type rating for DC-9 airplanes, but that day was receiving differences training in the MD-83. Until differences training was completed, the captain could not serve as pilot-in-command (PIC) of an MD-83 operated under FAR Part 121 by Ameristar. He held an ATP certificate with type ratings for the Boeing 747, DC-9 and Saab SF-340. He also held a flight instructor certificate.
He had been hired by Ameristar on Jan. 25, 2016, and had flown the DC-9 as a first officer before upgrading to captain on Feb. 26, 2016. He was also a proficiency check airman for the company DC-9 flight simulator. The captain had accumulated 15,518 hr. total flight experience, which included 4,752 hr. as PIC and 8,495 hr. in the DC-9. He had flown 68 hr., 30 hr. and 0 hr. in the previous 90 days, 30 days and 24 hr., respectively. He had flown into KYIP 10 times between April 17, 2016, and March 6, 2017, and his last three flights had been with the check airman (Jan. 8, 2017; Jan. 15, 2017; and March 6, 2017).
The 41-year-old check airman held an ATP with type ratings for the Boeing 737, DC-9, Dassault Falcon DA-20 and Learjet airplanes. He also held flight instructor and advanced ground instructor certificates. He was qualified for the company on the DC-9, MD-83 and 737 and was a check airman on the MD-83. He had accumulated 9,660 hr. total flight experience, which included 7,240 hr. as PIC and 2,462 hr. in the DC-9 (2,047 of which were as PIC). He had flown 50 hr., 19 hr. and 0 hr. in the previous 90 days, 30 days and 24 hr., respectively, and had flown 152 flights into KYIP (53 times on the MD-83) between Jan. 1, 2003, and March 6, 2017.
Rear view of the airplane wreckage. Credit: NTSB

For this flight, the captain was to be the pilot flying (PF) in the left seat and the check airman the pilot monitoring (PM) in the right seat. The check airman was also to be the PIC.
The pilots found their airplane on the west apron, completed a walkaround and initiated their preflight planning. The crewmembers considered the high gusting wind when discussing the V-speed calculations. They chose to use a maximum thrust takeoff, which was their normal procedure. They calculated these V-speeds: V1 (takeoff decision speed), 139 kt.; Vr (rotation speed), 142 kt.; and V2 (minimum takeoff safety speed), 150 kt.
The check airman later told investigators the wind was “pretty gusty,” so the pilots agreed to increase the rotation speed by about 5 kt. The CVR transcript indicated that the check airman advised the captain to “delay rotation until at least V2 . . . wait for me to call it.”
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The captain conducted a briefing affirming that the pilots would delay rotation “because of the gusty, strong gusty winds.” His briefing also considered wind in the event of an emergency. In the CVR transcript, he told the check pilot to “really keep an eye out on what our airspeed is doing today, ahm, in the event of an engine fire or failure at or after V1, we’re going to continue the takeoff. . . . If you get any kind of wind-shear warning — it’s gonna be max thrust, ah, all the way to the firewall thrust, if necessary . . . we’ll fly out of the shear, back me up on the, ah, airspeed calls.”
The NTSB concluded later that “the flight crew’s decision to use an increased rotation speed was appropriate for the known weather conditions and consistent with company procedures.”
Neither pilot had observed any anomalies with the airplane while performing the walk-around inspection or their predeparture procedures and checklist items.
Diagrams showing the relative positions of the links (blue) and actuating crank (gray) when moving within their normal range of travel (in green) and when locked overcenter after having moved beyond their normal range of travel (in red). Credit: NTSB

The airplane is a T-tail design with the elevators and horizontal stabilizer attached near the top of the vertical stabilizer at about 30 ft. AGL. The left and right elevators are attached by hinges to the rear spar of the horizontal stabilizer, and each is equipped with control, geared and anti-float tabs attached to the trailing edge. Each elevator can travel between 27 deg. TEU (trailing edge up) and 16.5 deg. TED (trailing edge down) between mechanical stops mounted on the horizontal stabilizer. A stop arm on each elevator contacts the mechanical stops to limit elevator travel.
Each elevator also is equipped with a damper designed to prevent elevator flutter during flight and to dampen rapid movement of the elevator during gusty wind when the airplane is on the ground. When the airplane is parked, each elevator is free to move independently within the confines of the mechanical stops if acted upon by an external force, such as wind or manipulation by maintenance personnel. By design, the elevator system has no gust lock, and the elevators are not interconnected.
Elevator control is accomplished via the trailing-edge elevator control tabs, which are mechanically connected to and directly controlled by the cockpit control column. During takeoff (at Vr or higher) and during flight, when a pilot provides aft or forward control column input to command a change in airplane pitch, the elevator control tabs mechanically deflect, and the resultant aerodynamic forces on the deflected control tabs move the elevator surfaces to produce the change in airplane pitch. For example, when a pilot pulls the control column aft to command airplane nose-up pitch (such as during rotation), the control tabs respond by deflecting TED, and the resultant aerodynamic forces move the elevators TEU.
Three potential problems exist with this configuration: (1) Pilots cannot determine the mechanical integrity of the elevators during the walk-around; (2) an elevator-control check in the cockpit only confirms that the tabs are moving (as opposed to the elevators); and (3) elevators can be damaged when strong/gusty winds swirl around a parked airplane.
The airworthiness standard current at the time of the accident specified that flight control systems and surfaces of transport-category airplanes must be designed for the limit loads generated when the airplane is subjected to a 65-kt. horizontal ground gust from any direction while parked and taxiing.
Operating and maintenance manuals require a hands-on inspection of the elevators if the airplane was exposed to steady state winds or gusts exceeding this limit. That inspection requires the pilots or maintenance crew to mount some sort of lift and manually move the elevator surfaces to assure freedom of movement.
At the time of the accident, Ameristar had no provisions for monitoring winds during the two days the aircraft was parked. However, even if such a system had been in place, there would have been no requirement for a manual inspection on the day of the accident. Winds at KYIP over the previous two days had not exceeded 50 kt. Unknown to everyone, however, winds on March 8 streamed over and around a nearby hangar, accelerating locally over 65 kt. and becoming locally turbulent, thereby causing the parked accident airplane’s elevators to bang from stop to stop. Internal linkage on the right elevator was damaged, but there was no way for the crew to know that.
Getting Weather Info
On March 8, nothing was easy for these pilots. The flight crew first powered up the airplane about 1236 and repositioned it to the terminal in preparation to board their passengers for a 1430 departure. At 1314:39, the flight crew listened to the ATIS recording that was from 1153. They were not sure this limited weather would meet the regulations for their flight, so they attempted to obtain the current weather information for KYIP from other sources. The check pilot told the safety board he used his cellphone to call the ATIS frequency but received a report that was “just an updated version of the previous weather with winds about 260 deg. at 40 kt.”
3-D visualization of wind simulation results for a discrete time showing the locations of the hangar and airplane. Wind flow from the west (left side) is disrupted downwind of the hangar. Credit: NTSB

Ultimately, the check pilot used his cellphone to obtain the weather observation at Detroit Metropolitan Wayne County Airport (KDTW), about 8 nm east of KYIP, and to call the Ameristar operations director to obtain a Real-Time Mesoscale Analysis (RTMA) temperature at KYIP. The CVR captured numerous phrases from the check airman consistent with cellphone calls to obtain weather information and ATC clearances up until 1448:46.
The NTSB reached out to the FAA to see if Flight 9363’s departure was actually legal under the circumstances faced by the crew. The agency stated:
“Although Part 121.651(a) is silent on the operational capabilities of weather facilities and the recency of reported weather . . . to operate consistently with this and other related regulations, a pilot must have a reasonable certainty that conditions existing at the time of takeoff have been accurately reflected by the weather report that is used to determine the flight will meet or exceed the required minimums and thereby ensure safe operation of the aircraft.”
The safety board noted that the weather conditions at KYIP were VFR based on the most recent METAR received by the flight crew, KDTW was reporting VFR conditions when the check airman called to receive the information, and the flight crew visually verified that the conditions at KYIP were VFR at the time of the departure. Thus, the Board concluded “that the flight crew’s preflight weather evaluation was sufficient to establish with reasonable certainty that the conditions existing at the time of takeoff met the required minimums for departure.”
Anyway, they got their passengers settled on board, and, clearance in hand from an FSS, they checked CTAF for traffic and headed for the runway.
The Takeoff
The check airman performed the flight control checks during taxi and felt nothing unusual when he moved the control column forward and aft. Taxi out was normal, and the pilots ran the checklist. They rechecked all of their V-speeds and increased Vr.
3-D visualization of wind simulation results for a discrete time showing turbulence generated downwind of the hangar. Credit: NTSB

All their conversation, said the safety board, was pertinent information during the taxi. They used Taxiway E1 to hold short of Runway 27. The check pilot coordinated with the FSS for their off-time, then they taxied toward Runway 23L.
Both pilots looked at the windsock and saw it was favoring Runways 23L and 27. They decided they would be more comfortable with 23L since they had typically used that runway for departure. They were aware of a Beechcraft Baron that had reported downwind to Runway 27.
The flight crew positioned the airplane for departure from Runway 23L. At 1451:12, the check airman called for the captain to begin the takeoff roll. At 1451:55, the check airman called “V1.” Six seconds later (at 1452:01), he called “rotate,” followed 3 sec. later (at 1452:04) by “V2.”
At 1452:05, the captain said, “Hey, what’s goin’ on?” and, 3 sec. later, “Abort.” The check airman stated, “No, not above . . .” and then “. . . don’t abort above V1 like that,” and the captain replied, “It wasn’t flying.”
At 1452:23, the CVR captured sounds consistent with the airplane’s excursion from the paved surface.
At 1452:37, the airplane came to a stop, and the check airman called “Evacuate, evacuate, evacuate” over the public address system. All 110 passengers and six crewmembers evacuated the airplane using four of the airplane’s eight exits. Flight attendants reported that two over-wing exits were not opened, and the right front door exit was unusable because the evacuation slide did not inflate.
During a post-accident interview, the captain recalled that, when he began a normal rotation of the airplane at the “rotate” call, it did not rotate, so he applied more back pressure. The captain said the control column was not quite to the physical limit of aft movement but was “farther back than for a normal rotation.” Both pilots stated in interviews that, after the captain called for the rejected takeoff, they applied maximum braking, but the airplane went off the end of the runway.
During the overrun, the nose landing gear and both main landing gear had bent, fractured and displaced aft. The fuselage lower skin panel assemblies, including longeron and frames, buckled and some sections tore off. Internal structure at several locations had been sheared.
Later, investigators established flight control continuity for the elevator system by exercising the cockpit control columns through their full range to the control column stops in both the aircraft nose-up and aircraft nose-down directions. The left and right elevator control tabs responded with movement in the appropriate direction. Then they used a lift to inspect the elevators and found that the airplane’s right elevator was jammed in a TED position and could not be moved when manipulated by hand. Examination found that the inboard actuating crank for the right elevator’s geared tab was bent outboard, and the actuating crank and links were locked over-center beyond their normal range of travel.
Analysis
The safety board took a long look at the captain’s decision to reject the takeoff beyond V1— the maximum airspeed at which a rejected takeoff can be initiated, and the airplane stopped on a runway that is limited by field length. What follows is the safety board’s analysis of that action.
Vertical cross-section visualization of wind simulation results for a discrete time showing flow pattern and horizontal (“U”) and vertical (“w”) wind magnitudes near the accident airplane’s elevators (view from behind looking forward). Credit: NTSB

Company guidance specified that initiating a rejected takeoff even 4 to 6 kt. (about 1 sec.) after V1 may result in a runway overrun at high speed. Although the flight crew’s use of the increased rotation speed to mitigate a possible wind-shear encounter during takeoff was appropriate, it resulted in the check airman not calling “rotate” until 5 sec. after the airplane achieved V1. By the time the captain recognized that the airplane would not rotate and called to abort the takeoff, 12 sec. had elapsed since V1, essentially guaranteeing that the airplane would overrun the runway.
Ameristar guidance and training specifically stated that the captain was solely responsible for the decision to continue or reject a takeoff and that the no-go decision must be made — and the appropriate procedures initiated — before the airplane reached V1. The guidance stated that, in many cases, rejected takeoffs at high speed have resulted in far more negative or catastrophic outcomes than would have been likely if the takeoffs had been continued. For decades, pilot training has extensively emphasized that the no-go decision must be made before V1.
However, company guidance also stated that a high-speed rejected takeoff should be made only for safety of flight items, such as a condition where there is serious doubt that the airplane can safely fly. Boeing guidance also stated that rejecting the takeoff after V1 is not recommended unless the captain judges the airplane to be incapable of flight.
In the case of this attempted takeoff, it was not until after the airplane had exceeded V1 that the captain discovered that the airplane would not rotate in response to his control inputs. When the check airman called “rotate,” the captain pulled back on the control column, observed that the airplane did not respond in pitch, then added more back pressure until the control column came “farther back than for a normal rotation,” but the airplane still did not respond.
The captain called for the rejected takeoff, and the flight crewmembers applied maximum braking, but the airplane went off the end of the runway. The airplane performance study showed that, assuming the same deceleration profile as that of the accident flight, the captain would have had to start braking 4 sec. sooner for the airplane to have come to a stop on the paved surface. However, at that point in the accident flight’s takeoff, the captain’s control column input had been applied for only 3 sec.
A review of FDR data showed that, during the airplane’s previous successful takeoff, at 3 sec. after control column input, the airplane had only begun to respond in pitch. Thus, the NTSB concludes that the airplane’s lack of rotational response to the control column input during the accident takeoff did not become apparent to the captain in time for him to have stopped the airplane on the runway.
Rarely could all of the safeguards in place to ensure an airplane is airworthy before departure (such as proper aircraft maintenance, preflight inspections and control checks) fail to detect that an airplane was incapable of flight, as occurred with the jammed elevator on the accident airplane. Perhaps even more remarkable was that a flight crew would be placed in a situation in which the airplane’s inability to fly would not be discoverable until after it had accelerated past V1 during a takeoff roll. The captain had extensive flight experience with many takeoffs, but none of them presented a scenario like the one he faced during the accident takeoff. Although he was relatively new to flying the MD-83, because of his prior experience in the DC-9, the captain correctly assessed the state of the accident airplane and quickly called for and initiated the rejected takeoff. Thus, the NTSB concludes that, once the airplane’s inability to rotate became apparent, the captain’s decision to reject the takeoff was both quick and appropriate.
Crew coordination during takeoff is essential to managing one of the most critical phases of a flight. Effective crew coordination and performance depend on the flight crewmembers having a shared mental model of each task; such a mental model, in turn, is founded on effective standard operating procedures (SOPs) (FAA 2017b). Flight crew adherence to SOPs during a takeoff, including maintaining the defined roles of PF and PM, is of paramount importance to flight safety (FAA 2017b).
Although Ameristar’s procedures for a rejected takeoff clearly establish that the responsibility for the go/no-go decision is exclusively that of the captain, in this flight, the PM was also a check airman providing airplane differences instruction to the captain trainee; thus, the check airman was the PIC of the flight. This increased the potential for confusion as to who was truly responsible for the go/no-go decision during an anomalous situation. Instructors typically have more experience in the airplane than the pilot receiving instruction (as was the case with this crew) and are primed to assume control should the trainee’s actions pose a risk to the flight.
Although the check airman instinctively reached toward the control column after the captain’s “abort” callout (and stated to the captain that they should not reject a takeoff after V1), the check airman did not take control of the airplane but rather observed that the captain had initiated the rejected takeoff procedures and then took action to assist the captain in executing those procedures.
The flight crew’s coordinated performance around the moment that the captain rejected the takeoff showed that both pilots had a shared mental model of their responsibilities. By adhering to SOPs — rather than reacting and taking control of the airplane from the captain trainee — the check airman demonstrated disciplined restraint in a challenging situation. Had the check airman simply reacted and assumed control of the airplane after the captain decided to reject, the results could have been catastrophic if such action were to further delay the deceleration (at best) or to try to continue the takeoff in an airplane that was incapable of flight.
Thus, the NTSB concludes that the check airman’s disciplined adherence to company SOPs after the captain called for the rejected takeoff likely prevented further damage to the airplane and reduced the possibility of serious or fatal injuries to the crew and passengers.
Probable Cause
The safety board determined the probable cause of this accident “was the jammed condition of the airplane’s right elevator, which resulted from exposure to localized, dynamic wind while the airplane was parked and rendered the airplane unable to rotate during takeoff.”
Contributing to the accident, it continued, were (1) the effect of a large structure on the gusting surface wind at the airplane’s parked location, which led to turbulent gust loads on the right elevator sufficient to jam it, even though the horizontal surface wind speed was below the certification design limit and maintenance inspection criteria for the airplane, and (2) the lack of a means to enable the flight crew to detect a jammed elevator during preflight checks of the airplane.
And contributing to the survivability of the accident, it stated, was “the captain’s timely and appropriate decision to reject the takeoff, the check airman’s disciplined adherence to standard operating procedures after the captain called for the rejected takeoff, and the dimensionally compliant runway safety area where the overrun occurred.”
Since this accident, Boeing engineers have designed new elevator stops that protect the tab linkage, and the FAA has impressed on rated weather observers the importance of properly configuring the ASOS. Ameristar (and many other operators) have worked up protocols to monitor winds during periods when their airplanes are parked.