# Tangential Method Calculation

The tangential method is the simplest calculation among other directional survey calculations.

The tangential method formulas are listed below;

Tangential Method Calculation formula

Where;

MD = Measured Depth between surveys in ft

I1 = Inclination (angle) of upper survey in degrees

I2 = Inclination (angle) of lower in degrees

Az1= Azimuth direction of upper survey

Az2 = Azimuth direction of lower survey

The following example is the Tangential Method Calculation.

Survey 1

Depth = 3500 ft

Inclination = 15 degree (I1)

Azimuth = 20 degree (Az1)

Survey 2

Depth = 3600 ft

Inclination = 25 degree (I2)

Azimuth = 45 degree (Az2)

Solution:

MD = 3600 – 3500 = 100 ft

As per the formulas above, you will get answers as listed below;

North = 29.88 ft

East = 29.88 ft

TVD = 90.63 ft

Please find the Excel sheet used for The Tangential Method Calculation

Reference books: Directional Drilling Books

Formulas and Calculations for Drilling, Production and Workover, Second Edition

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### 4 Responses to Tangential Method Calculation

1. chinonso says:

i acknowlegde this site for their work well done.

2. There are several methods that can be used to calculate the survey data, of these some are accurate while are other may produce some error for a given situation.
Some of the most common methods used for survey calculation in the industry are:
Tangential method (Least Accurate)
Balanced Tangential method
Average Angle method
Radius of Curvature method (Most Accurate)
Minimum Curvature method (Most Accurate)

You’ve done a fine job, I thank you for sharing your knowledge.

3. manmohan says: