Century Heli
Senior Heliman
Location: CA. USA
| Technical update (03/24/06)
Dear valued customers,
In an effort to provide existing customers with Swift helicopters the best possible service, we have decided to offer free of charge some revised parts that should provide a solution to those that are having an issue with a shake or vibration during the spool up/down phase. A small percentage of Swift helicopters have been found to exhibit this shake during spool up/down.
Symptom(s):
During spool up and spool down of the rotorhead, the helicopter exhibits a violent shake or vibration.
Reason(s):
During the manufacturing process, the tolerances of the plastic head block in comparison to the size of the machined ball on the feathering spindle were too closely matched. The size of the internal diameter in which the feathering spindle feeds through has decreased in diameter due to the natural absorbtion of moisture from freshly manufactured plastic parts. This "shrinking" of the internal diameter manifests itself during the first 30-60 days after a plastic injected part has come out of a mold. This results in tolerances too close to the size of the feathering shaft. The self centering floating feathering shaft system is defeated at lower head speeds, therefore causing a vibration during the spool up/down phase. When the head speed of the helicopter approaches higher head speeds, the optimum amount of centrifugal force allows the spindle to center itself allowing for smooth flight characteristics.
If the helicopter is placed on a hard surface (i.e. cement, tarmac), the tall and thin landing gear amplifies the shakes during the spool up/down phase.
Resolution(s):
All r/c helicopters exhibit vibrations as soon as the rotor head turns and there are no vibration-free helicopters. It is how they hide this characteristic that matters to the pilot. In regards to the Swift, the overall weight of the helicopter compared to the amount of rotational mass in the head including the blades can cause a more than desirable "shake" of the helicopter. The tolerances of the head block and the feathering spindle were manufactered too closely resulting in some head blocks preventing smooth movement of the feathering spindle. New headblocks have been manufactured to prevent this problem. Currently shipping Swift helicopters have this revised head block.
The shakes are also amplified by the tall landing gear. The reason for the tall landing gear is to keep the battery further off the ground. The reason they are thin is to reduce overall weight. New tooling has been made to produce thicker and more re-enforced landing gear. Currently shipping Swift helicopters have this revised landing gear.
If you purchased your Swift between November 1st, 2005 through February 15th, 2006 and only if you are experiencing a shake or vibration on spool up or spool down, please go to this form and fill out the requested information to receive these revised parts. If you purchased your Swift after February 15th, 2006, you should already have the revised parts.
Please allow 2-3 weeks for delivery of revised parts.
Please follow the rule of "If it ain't broke, don't fix it." as you may experience other problems if you try to fix a non-existant issue on your operational Swift.
Thank you,
Century Helicopter Products |
