In the above example, either correction would be acceptable

STUDENT GUIDE

VISUAL NAVIGATION

values. With this in mind, if we are only half as far off course ( NM), we hold the

correct for half as long. One should also note all corrections are applied to errors in

NM increments (, 1, 1, etc) for times that are in 30 second intervals (+30, 1+00, 1+30,

etc). In the following example be sure to take note of the specific manner in which the

correction is called for:

EXAMPLE 7-4: After Fixing, analyzing, and compensating, you are 1 NM left of course,

compensated heading 090. What is your correction? The elapsed time is now 5+30

A. One option is to simply correct back with 10 of correction for 1 minute of time.

"Right 100, time in 5+30, time out 6+30."

B. Another option is to turn 20 for 30 seconds:

"Right 110, time in 5+30, time out 6+00."

7.7.1.1.1.1. In the above example, either correction would be acceptable. Additionally,

you have the option of extending or reducing the time of correction once it is initiated.

This might be necessary if, during the correction, a checkpoint confirms the aircraft is

closer or further away from course than expected. Finally, a technique many instructors

recommend is placing a mark on their course line as a reminder to take out the correction.

7.7.1.1.1.2. As with all corrections, they are made off compensated headings, and 30 is

the largest correction allowed.

7.7.1.1.2. BDHI Corrections: The BDHI maneuver is nothing more than intercepting a

planned course that leads to a specific visual feature. It is the visual low-altitude version

of "intercepting the radial." In fact, the term "BDHI" refers to "Bearing Distance Heading

Indicator," the equipment for which this technique was originally employed.

7.7.1.1.2.1. The same guidelines for using the BDHI procedure in T-34 flights applies to

T-1 and T-39 operations. The principle guidelines, first presented in Unit 5 (T-34

VNAV) are:

!" he checkpoint must be on or closer to course than the aircraft. It may not be on the

opposite side of planned track.

!" he checkpoint must be in sight and within 30 degrees of compensated heading (11 to

1 o'clock).

!" he aircraft is an unknown distance from planned course (otherwise perform a

standard correction.)

7.7.1.1.2.2. With the above conditions met, the BDHI is executed in the same manner,

the most significant difference being the requirement to lead the return to compensated

heading:

!" all for a 30o turn from compensated heading towards the checkpoint.

!" s the aircraft turns to the new heading, the visual point will drift to the opposite side

of the 12 o'clock position. Call "steady up" after this occurs.

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