N641UA

HISTORY OF FLIGHTOn July 29, 2023, about 1034 central daylight time (CDT), United Airlines flight 702, a Boeing 767-322, N641UA, sustained substantial damage while landing at George Bush Intercontinental Airport (IAH), Houston, Texas. The 202 passengers and crew aboard the airplane were not injured. The flight was operating as a Title 14 Code of Federal Regulations Part 121 scheduled domestic passenger flight from Newark Liberty International Airport (EWR), Newark, New Jersey, to IAH.

The first officer (FO) was the pilot flying, and the captain was the pilot monitoring. The flight crew reported that the departure from EWR and the cruise segment of the flight were uneventful. The airplane was cleared for the DOOBI2 arrival to IAH and then the instrument landing system approach to runway 26L. According to the flight crew, the airplane was fully configured for landing, on speed, and in compliance with the company’s stable approach criteria, and the initial touchdown on the main wheels was normal.

The FO stated that, after the main landing gear touched down, he held aft pressure on the control yoke to keep the nosewheel from hitting the runway, but the nosewheel contacted the runway with “abnormal force.” The airplane seemed to bounce, and the FO reacted by pulling the control yoke aft to keep the nosewheel from impacting the runway a second time.

Flight data recorder (FDR) data indicated that control column inputs ranged from about 5° nose high to 5° nose low during the landing. Data also indicated that the speedbrakes deployed simultaneously as the thrust reversers transitioned from not deployed to deployed, and the nosewheel bounced a second time. Subsequently, the nosewheel contacted the runway a third time and the airplane began to decelerate.

The captain assumed control of the airplane, and the remainder of the landing rollout was normal. PERSONNEL INFORMATIONThe Captain

The captain was hired by United Airlines in April 2001 as a first officer. At the time of the accident, the captain was based at EWR, and he held type ratings in the Airbus 320 and Boeing 737, 757, and 767.

According to the captain’s training records, his most recently completed training included a proficiency check and emergency drill training on June 12, 2023, crew resource management on April 24, 2023, and initial operating experience on October 23, 2022. His most recent line check was completed on January 21, 2023.

The First Officer

The FO was hired by United Airlines on February 7, 2023. At the time of the accident, the first officer was based at EWR, and he held type ratings on several airplanes, including the Boeing 757 and 767.

The first officer completed the required training and his initial line-oriented evaluation checkride on April 28, 2023, receiving an unsatisfactory performance rating due to deficiencies with takeoffs and aircraft control. During his second checkride, the FO obtained a satisfactory performance rating but received the minimum grade in three areas, one of which was landings, which resulted in a “short cycle.”

A short cycle allowed the first officer to proceed with operating experience but required him to be evaluated in 90 days rather than the normal period of 9 months. According to the check airman who completed the FO’s second line-oriented evaluation, the purpose of the short cycle was to ensure that the FO’s “proficiency is up to standards” given his previous “struggles.” AIRCRAFT INFORMATIONThe speedbrake on the accident airplane was controlled by the speedbrake lever, which was located on the control stand. The speedbrake had three positions: down, armed, and up, which were identified by demarcation lines.

The Boeing 767 Flight Crew Operations Manual, dated October 11, 2019, stated in part the following:

The speedbrake lever can be placed in an intermediate position between ARMED and UP.

In the ARMED position, when the landing gear is fully on the ground (not tilted) and the thrust levers are at idle, the speedbrake lever is driven aft to the UP position and the spoiler panels are fully extended.

On the ground, when either thrust lever is moved to the reverse idle detent, the speedbrake lever is driven to the up position and the spoiler panels are fully extended. The speedbrake lever does not need to be in the ARMED position. METEOROLOGICAL INFORMATIONIAH was equipped with an automated surface observing system. A review of the observations 15 minutes before and 10 minutes after the accident revealed that the wind was coming from the southsouthwest at a speed of 5 knots or less. AIRPORT INFORMATIONThe speedbrake on the accident airplane was controlled by the speedbrake lever, which was located on the control stand. The speedbrake had three positions: down, armed, and up, which were identified by demarcation lines.

The Boeing 767 Flight Crew Operations Manual, dated October 11, 2019, stated in part the following:

The speedbrake lever can be placed in an intermediate position between ARMED and UP.

In the ARMED position, when the landing gear is fully on the ground (not tilted) and the thrust levers are at idle, the speedbrake lever is driven aft to the UP position and the spoiler panels are fully extended.

On the ground, when either thrust lever is moved to the reverse idle detent, the speedbrake lever is driven to the up position and the spoiler panels are fully extended. The speedbrake lever does not need to be in the ARMED position. WRECKAGE AND IMPACT INFORMATIONA postaccident examination of the airplane revealed damage to the crown of the upper fuselage. The fuselage skin was buckled and fractured, as shown in figure 1, with damage to the underlying stringers and frames.

Figure 1. Close-up view of the airplane damage on the left side of the fuselage (Source: United Airlines). ADDITIONAL INFORMATIONDe-rotation is the lowering of the aircraft’s nose gear to the runway following touchdown on the main gear during landing. In a review of National Transportation Safety Board investigations and assisted international investigations, there were seven similar de-rotation accidents involving Boeing 757/767 aircraft. Those investigations were:

January 16, 1992 - Asiana Airlines in Cheu Island, South Korea

October 27, 1992 – American Airlines flight 957 in São Paulo, Brazil

December 31, 1993 – LOT flight 002 in Warsaw, Poland

July 31, 1997 – Federal Express in Newark, New Jersey

May 22, 2002 – Monarch Airlines in Gibraltar

April 20, 2009 – Royal Air Maroc flight 200 in New York, New York

August 18, 2019 – Delta Air Lines 414 in Ponta Delgada, Portugal

These accidents occurred when the pilots applied large nose-down control column deflections after main landing gear touchdown, which resulted in large nose-down pitch rates and high vertical velocities at the nose gear. It was this combination of vertical velocity and pitch rate that resulted in compression loads that exceeded the design loads of the forward fuselage crown structure. FLIGHT RECORDERSA review of FDR data revealed that the airplane touched down on both main wheels, with a control column position of about 0.35° and the speedbrake handle in the down (unarmed) position. After the initial touchdown, the maximum recorded control column positions during the landing sequence were 5.71° to 4.75°, as shown in figure 2. FDR data also showed that the airplane rolled to the left and that the right main landing gear lifted off the runway’s surface. Subsequently, the nosewheel impacted the runway with a force equivalent of about 1.4 gravitational force equivalent (G). The thrust reversers were in transit as the speedbrakes deployed, and the nosewheel impacted the runway a second time with a force of about 1.6 G and bounced. Subsequently, the nosewheel impacted the runway a third time with a force of about 1.6 G.

Figure 2. FDR data pertinent to the circumstances of this accident. ORGANIZATIONAL AND MANAGEMENT INFORMATIONUnited Airlines 757-767 Flight Manual

The United Airlines 757-767 Flight Manual, dated June 30, 2023, Normals, Landings, stated in part the following:

[PF, PM] Touchdown and rollout. . . . . . . . . . . . . . . . . Accomplish/monitor

Ensure that the airplane is not allowed to pitch up after touchdown. Fly the nose down to the runway.

For a normal landing, plan for touchdown at least 1000 feet from the threshold. Hold sufficient back pressure on the control column to keep the pitch attitude constant. Touchdown should occur at an airspeed of no less than VREF. This typically results in main gear touchdown approximately 1500-1800 feet from the threshold.

If the EICAS advisory AUTOBRAKE displays or if deceleration is not normal, brake manually.

[PM] Speed brakes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Monitor

Announce abnormal operation. If automatic extension fails, the Captain slowly raises the speed brakes to the up position while the nose is smoothly lowered to the runway.

Boeing 767 Flight Crew Training Manual

The Boeing 767 Flight Crew Training Manual, dated June 30, 2023, provided the following landing procedure guidance:

After main gear touchdown, initiate the landing roll procedure. Fly the nose wheels smoothly onto the runway without delay. IF the speedbrakes do not extend automatically move the speedbrake lever to the UP position without delay. Control column movement forward of neutral should not be required. Do not attempt to hold the nose wheels off the runway. Holding the nose up after touchdown for aerodynamic braking is not an effective braking technique and results in high nose gear sink rates upon brake application and reduced braking effectiveness.

To avoid possible airplane structural damage, do not make large nose down control column movements before the nose wheels are lowered to the runway.

The Boeing 767 Flight Crew Training Manual also provided the following flare and touchdown guidance:

The techniques discussed here are applicable to all landings including one ...