Service Bulletin Number 0004
Date Released: 2023.07.24
Impact: All Switchblade-Elite Mk2.2, Mk2.2HV aircraft, and spare rotor sets equipped with KDE rotor hubs delivered by Vision Aerial from 16 September 2022. Includes but may not be limited to aircraft with the following serial numbers: SN20113, SN20115, SN20131, SN20138, SN20148, SN20169, SN20171, SN20172, SN20173.
Introduction
The rotor hub fasteners used during this time period can potentially shear, which could lead to a flight critical failure.
Description
It was recently discovered that one of our vendors had fasteners made with substandard material. In conjunction with that vendor Vision Aerial thoroughly investigated the issue and found that these substandard fasteners could be traced back to the 16th of September 2022. The rotor hub fasteners were specced to be Grade 12.9 and have a minimum yield strength of 160 KSI. The fasteners subject to this Service Bulletin were not rated and thus can be assumed to be of lower quality.
Any shearing of the rotor hub fasteners can lead to the loss of the rotor blade in flight, and is cause for immediate grounding of the aircraft until the rotor hub fasteners and blades are replaced. To date this has been observed in only two instances.
Resolution
Moving forward all aircraft identified in this Service Bulletin will receive a new set of rotor hub fasteners for each rotor set, and installation instructions. Vision Aerial will contact all Customers affected by this Service Bulletin and there will be no Customer cost to replace those systems currently deployed in the field.
Customer Impact
Customers will need to modify their rotor hubs using the provided hardware in accordance with the provided instructions.
If you have any questions or feedback, please contact Vision Aerial via [email protected].