Solution: Angles from Directions Set 1

Problem (1)

Compute deflection angles at points B through F for the link traverse below. Identify and perform a math check.

Complete solution

At point B

δ_B = 180°00’00” - (30°00’00” + 61°19’50”) = 88°40’10”

Del Ang_B = 88°40’10”R

At point C

δ_C = 61°19’50” + 43°58’35” = 105°18’25”

Del Ang_C = 105°18’25”R

At point D

δ_D = 43°58’35” + 76°54’05” = 120°52’40”

Del Ang_D = 120°52’40”L

At point E

δ_E = 180°00’00” - (76°54’05” + 70°41’05”) = 32°24’50”

Del Ang_E = 32°24’50”L

At point F

δ_F = 70°41’05” - 22°55’50” = 47°45’15”

Del Ang_F = 47°45’15”L

Answers
Point	Defl Angle
B	88°40'10" R
C	105°18'25" R
D	120°52'40" L
E	32°24'50" L
F	47°45'15" L

Math check?

The deflection angle sum should be the same as the difference between the beginning and ending bearings. Since both bearings are in the NE quadrant, the total bearing change is (To Bearing - From Bearing):

Adding up the deflection angles:

Ta-daa.