Pilot's prosthetic arm comes lose resulting in rough landing [tech analysis, wild guess]

We all learned that a pilot's prosthetic arm had come lose resulting in a rough landing. From [link]:

The pilot was sitting on the left of the Dash 8 cockpit when his artificial left arm detached from the controls. (..) A pilot lost control of a passenger plane after his artificial arm became detached as he was coming in to land, an accident report has said. The Flybe flight from Birmingham, with 47 passengers on board, was approaching Belfast City Airport in gusty conditions on 12 February. It landed heavily but no-one was hurt and the plane was not damaged.

The pilot said he would be more cautious in future about checking his attachment, according to the report. In a statement, Flybe said the senior captain was one of its "most experienced and trusted pilots", and the safety of passengers and crew had not been compromised in any way. Flybe said the senior captain was one of its most experienced and trusted pilots.

Shortly before beginning to land the Dash 8 aircraft, the 46-year-old had checked that his prosthetic lower left arm was securely attached to the clamp that he used to fly the aircraft, with the latching device in place. The Air Accidents Investigation Branch (AAIB) report said the captain had disconnected the autopilot and was manually flying the aircraft. However, as he made the flare manoeuvre - a stage of the landing shortly before touchdown - "his prosthetic limb became detached from the yoke clamp, depriving him of control of the aircraft". Pilot Steven Robinson: "I do it one-handed". While he had thought about getting his co-pilot to take control, the time available and the challenging conditions meant his best course of action was to move his right hand from the power levers on to the yoke to regain control. "He did this, but with power still applied and possibly a gust affecting the aircraft, a normal touchdown was followed by a bounce, from which the aircraft landed heavily," the report found. The AAIB reported that the captain had said that in future he would be more cautious about checking the attachment on his prosthesis as he may have dislodged the latching mechanism. He also said he would brief his co-pilots about the possibility of a similar event and that they should be ready to take control at any time. Captain Ian Baston, Flybe's director of flight operations and safety, said it was an equal opportunities employer and "in common with most airlines, means we do employ staff with reduced physical abilities".

"The safety of our passengers and crew is our number one priority," he said. "This means that Flybe not only adheres to the Civil Aviation Authority's strict requirements relating to the employment of staff with a reduced physical ability, but exceeds them to ensure that safety is never compromised. He said an internal investigation following the incident had "determined a series of additional failsafe safety checks" that had been implemented "immediately to ensure that this type of incident could not happen again".

Other news [link] [link] [link] [link].

Vibration

The most likely reason this happened is, in my experience with my prosthetic arms, vibration.

Vibration is the ultimate killer for reliability of screw fastened prosthetic arm joints anywhere, but in particular, at the wrist and further out. There, vibrations are extreme. My wrist is certainly screwed into the seal in ring very well but screws come undone regularly within 3-4 weeks.

Vibration and screws

Sure, mankind understand the problem, check these Junker tests:

Solutions

High tech screws and washers, locktite

Despite high tech administered to the screws, vibration still wins, always:

Proactively re-fasten screws regularly

The key is to proactively, unprovokedly, fasten the screws regularly. So a man has to carry screw drivers at all times.

My keyring screw drivers to begin with, and more in my bag and car and at home and anywhere else.

Cite this article:
Wolf Schweitzer: Technical Below Elbow Amputee Issues - Pilot's prosthetic arm comes lose resulting in rough landing [tech analysis, wild guess]; published August 20, 2014, 12:37; URL: https://www.swisswuff.ch/tech/?p=3376.

BibTeX: @MISC{schweitzer_wolf_1582458058, author = {Wolf Schweitzer}, title = {{Technical Below Elbow Amputee Issues - Pilot's prosthetic arm comes lose resulting in rough landing [tech analysis, wild guess]}}, month = {August},year = {2014}, url = {https://www.swisswuff.ch/tech/?p=3376}}