Baseline sloping distance AB and height h1 of the observer.
Angles measured at A – Vertical angles α and δ (slope of ground between A and B).
Angle measured at B – Vertical angle β.
Solution: Height of object above ground at position A.
First, measure sloping distance AB. From observer point A1, measure vertical angles α and δ. From observer point B1, measure vertical angle β.
In triangle A1ΟB1,
Then calculate sloping distance A1O:
Finally, calculate height of object above ground at station A: