airframe Vibration in the Forward Fuselage area
How an airframe Vibration in the
Forward Fuselage area can be isolated to the nose landing gear wheels? What
preventive maintenance actions help?
- Fuselage Vibration can have multiple contributing factors, Nose wheel & tire assemblies are among the most prominent.
- How to isolate, if the vibration is due to MLG or NLG during take-off run or just after Lift-off?
- If, after the Liftoff, Vibration stops immediately after the landing gear selection lever is selected Up or Brakes applied, Vibration the source is the Main landing gear.
- If, after the Liftoff, the Vibration diminishes gradually, vibration is due to the Nose wheels.
What causes the Nose wheels to initiate a Vibration?
- Nose wheel static balancing - Proper balancing of Nose wheels at workshop level is key to solve many vibration issues.
- Nose wheel Bearings - Premature wear of Nose wheel bearings also contribute most of the vibration cases linked to NLG.
- Factors behind the worn-out Nose wheel bearings are "Improper Installation", "Operating conditions", "Bearing environment" & "Improper Lubrication".
- Bearing deterioration can be avoided by proper Cleaning, inspection, torquing & Pre-load Rotation of wheels (Roller seating).