Helicopter guidelines for land seismic & helirig operations - OGP

Helicopter guidelines for land seismic & helirig operations
Annex F
Line helipad diagram and considerations
Dimensions for use in tall growth vegetation/trees for clearings and helipads
Trees
b
c
a
Trees
Level landing platform
No obstructions > ¼
distance between
ground and tail rotor
Felled trees
c
Trees
Dimensions:
a: sides the width of undercarriage + 2m, provided the pilot can see the gear
b: diameter equal to total length of helicopter, including rotor blades
c: sides 3 x total length of helicopter including rotor blades or 50m, whichever is greater
F.1 Landing areas and clearings
These dimensions quoted above will have the most relevance to operations in forested or jungle
areas where the cost and time impact of felling trees and clearing large tracts of vegetation is
greatest.
In areas where the terrain is hospitable, an increase in the level of safety may be achievable at
a reasonable cost by increasing the dimensions of the cleared area. Long line systems for the
carriage of external loads may also prove beneficial by dramatically reducing the size of many
clearings. However, full size clearings and landing pads will still be required for the movement
of passengers and internal cargo. The intervals along lines at which helipads will be required will
depend on such factors as the type of seismic recording equipment used and the expectations of
the labor force.
© OGP
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