Runway excursion of Jetstream 4100 caused by improper weight and balance loading

Casualties unknown • Manchester Airport, Manchester, GB

A Jetstream 4100 veered off the runway at Manchester Airport following a period of uncontrollable directional oscillations during landing.

What happened

On 29 June 2005, a Jetstream 4100, registration G-MAJA, was operating a passenger charter flight from Hamburg to Manchester. During the turnaround in Hamburg, the aircraft was loaded with heavy baggage that was not weighed by ground handling agents. The commander, estimating the weights based on the volumetric capacity of the holds, recorded the baggage as meeting the maximum allowable limits. To compensate for the heavy aft load, the commander instructed the cabin attendant to seat passengers in the forward rows of the cabin.

During the approach to Manchester Airport, the aircraft was flown via autopilot. Upon disconnecting the autopilot at approximately 80 feet, the aircraft exhibited pitch oscillations. Following touchdown, the aircraft experienced a period where only the nose wheel was in contact with the ground. This was followed by a rapid development of directional oscillations in yaw. Despite the use of rudder and braking, the aircraft's heading changed significantly, eventually leading the aircraft to depart the paved surface and come to a halt on the grass approximately 80 meters from the runway centreline. There were no injuries to the 3 crew members or 10 passengers on board, and no damage was sustained by the aircraft.

The investigation

The AAIB investigation established that the actual loading of the aircraft differed significantly from the loadsheet. While the crew believed the baggage was within limits, a subsequent inspection revealed that the combined weight of the baggage in the holds exceeded the maximum allowed by 122.9 kg. Furthermore, the distribution of weight was incorrect; the actual centre of gravity (CG) was positioned aft of the operator's approved flight envelope, although it remained within the manufacturer's more permissive limits.

The investigation also found that the passenger seating did not match the loadsheet. Because the cabin attendant did not utilize the first row of seats due to their proximity to the bulkhead, the actual passenger weight distribution was more aft than documented. The investigation also examined the nosewheel steering (NWS) system following reports of sensitivity at high speeds, but found no mechanical failure responsible for the excursion.

Findings

  • The aircraft was loaded with a centre of gravity positioned aft of the operating company's approved flight envelope.
  • Baggage was loaded into the holds without being weighed, with the commander relying on estimates.
  • The loadsheet failed to accurately reflect the actual passenger seating positions.
  • The aircraft experienced divergent directional oscillations during the landing roll, which the pilot was unable to correct.
  • The heavy aft loading likely contributed to the period of instability and the difficulty in maintaining directional control during the landing phase.

Probable cause

The primary cause of the runway excursion was the aircraft being loaded with a centre of gravity outside the operator's approved limits, resulting from unweighed baggage and inaccurate passenger seating documentation.

Frequently asked questions

What happened in the 2005-06-29 Jetstream 4100 accident near Manchester Airport, Manchester, GB?

A Jetstream 4100 veered off the runway at Manchester Airport following a period of uncontrollable directional oscillations during landing.

What aircraft was involved and where did it happen?

The accident on 2005-06-29 involved a Jetstream 4100, registration G-MAJA, at Manchester Airport, Manchester, GB.

What was the probable cause of the accident?

The primary cause of the runway excursion was the aircraft being loaded with a centre of gravity outside the operator's approved limits, resulting from unweighed baggage and inaccurate passenger seating documentation.

Loading the flight search…