25-01-2013, 09:27 AM
CHECKING PROCEDURE OF WING DIHEDRAL ANGLE OF PUSHPAK AIRCRAFT
CHECKING.docx (Size: 14.27 KB / Downloads: 22)
AIM
To ensure correct alignment of wing fitment in order to achieve the dihedral angle for stability purpose
THEORY
Wing dihedral angle is the upper inclination of the wing to fuselage given to provide the desired lateral stability during the roll of the aircraft
OCCASION
Heavy landing report given by pilot
Flight flown through high turbulence
On erection/assemble of new aircraft
Renewal or re fitment of wings
As and when required by DGCA
TOOLS REQUIRED
Dihedral board
Aircraft jacks and trestles
Plumb bob
Leveling board
Spirit level
Weighing machine
PRECAUTION
Observe all safety precaution for jack up
Check the accuracy of spirit level
Always finish leveling procedure once by checking the longitudinal level without any adjustment
PROCEDURE
Jack up and level the aircraft by taking proper precaution and preparation
Place the wing dihedral board at specified station along the spar between rib no.1 and rib no.4 front spar
Place the spirit level on dihedral board
Check the bubble location and if found at centre the dihedral angle is considered to be correct
In case of deviation the angle considered to be more or less depending on its position
In method 3, bevel protector is used to check dihedral angle
Set the angle specified by aircraft manufacturer in bevel protector
Place the bevel protector on the surface of wing between ribs no.1 and rib no.4 front spar for checking
In case of gap between bevel protector and using surface there is deviation depending on its position
Bevel protector can be adjusted to find deviation.
RESULT
The dihedral angle of pushpak aircraft is checked as per maintenance manual and found to be-------