Figure 7-1 - P-8120046

STUDENT GUIDE

VISUAL NAVIGATION

available for analysis and computations is much less, and "UPDATING" the time to a given

point becomes even more critical. There are other changes to the "visual picture" as well.

7.4.2. Visual Navigation

7.4.2.1. The equations and techniques used for basic fix analysis were introduced in UNIT 5 (T-

34 VNAV). As with T-34 VNAV flight, analysis follows the fix and is based on error over time

flown. This process requires a base indicated air speed is flown equating to 300 TAS. Prior to

low-level entry, compute the correct base IAS by using the ram air temperature and the

"Temperature vs. IAS" table located in the In-flight Guide (Figure 7-1) for the T-1A. T-39

conversions are included in the PCL.

7.4.2.2. While initial sources of wind information include the base weather shop and Flight

Service, there are two methods of wind determination that provide information regarding the

actual winds affecting the aircraft. These methods are visual and track analysis, and in both

require application the "Fix, Analyze, Compensate, Correct and Update" process.

7.4.3. Visual Analysis

TEMPERATURE VS. IAS

(FOR 300 TAS)

7.4.3.1. Perhaps the quickest way to estimate wind is

through visual analysis. There are several visual cues

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enabling accurate wind analysis. Flying at altitudes as

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low as 500 feet AGL, these cues will typically be closer

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to the aircraft than they were for T-34 sorties. This

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300

equates to both a more accurate visual analysis as well

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as the aircraft being closer to the perceived wind's

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altitude. While the most frequently used of visual cue is

smoke (Figure. 7-2), other cues include water effects,

Figure 7-1

windsocks, flags and foliage. Students may use visual

analysis as a source for wind information or for

supporting track analysis computations. However,

students must still separate winds computed using

visual analysis into component winds. The guide in

figure 7-5 illustrates the separation of components.

7.5. TRACK ANALYSIS

7.5.1. While track analysis requires more time for computation, it is typically more accurate and

provides specific wind components for compensation. Additionally, this method can compensate

for some of the effects of errors due to mission planning inaccuracies.

7.5.2. Good track analysis begins by following the "FIX, ANALYSE, COMPENSATE,

CORRECT, UPDATE" path. What follows is an in-depth discussion of each component and its

application at 300 KTAS and 500 feet AGL.

7-3