Unknown Rounding

INTERCEPT PROCEDURES TEXTBOOK

Unknown Rounding

The fighter should attempt to determine the bogey's heading whenever the opportunity

presents itself. The process is very simple. Once steady on a heading, whether after the initial or

secondary corrections, round the fighter's heading to the nearest 10 degrees (ie, 352 rounds to

350 degrees). Add or subtract the cut that is now being assumed and the fighter will have the

estimated bogey reciprocal; from there, the heading should be very easy to calculate. Your

initial heading estimate may be off by a lot but after a secondary correction (or two), the fighter

should be able to calculate bogey heading within 20 degrees.

Example #1--No Radar Contact for Initial/Secondary Corrections

(1)

The fighter, Sweep, has steadied-up on a heading of 340 after the initial GCI call of

"Gritrock, picture, single group, Bull 220-42, medium, flank east."

(2)

Once steady, the fighter does not have radar contact after the next GCI call and

therefore commands "Gritrock go tactical for Sweep." GCI responds with "Sweep,

Gritrock, single group, BRA 326-24, medium." The fighter then turns to place the

contact exactly on the nose (new fighter heading 326.

(3)

Once the fighter is steady, the next two calls are BRA 326-23 and BRA 327-22. After

hearing right drift, the fighter classifies the DOP as left-to-right and counters the drift

by commanding "Right hard" to place the magnetic bearing call at 30L AO (with a

heading of 357).

(4)

The fighter estimates a 60L cut, 30R TA. The weapons officer continues to analyze

drift for further corrections.

(5)

The fighter has steadied on 357 after the initial correction.

(6)

Subsequent GCI calls are "328 at 21 miles" (no reaction is made since this is the new

starting point for subsequent drift analysis), and "329 at 20 miles".

(7)

Continuing to analyze the left to right drift, the weapons officer commands the fighter

"Right hard" to counter the drift and place the magnetic bearing call at 50L AO. The

turn is commenced immediately after observing any drift - drift is notquantified during

secondary drift analysis.

(8)

The fighter has steadied-up on 019 after the secondary correction.

(9)

The weapons officer now estimates a 100L cut, 50R TA, and BH 100.

(10) The next bearing calls are "329 at 19 miles" and "328 at 17 miles."

(11) After noting the outward drift, the weapons officer commands "Left hard" to place the

bogey at 40L AO making the fighter's heading 008.

(12) The updated estimate is an 80L cut, 40R TA and BH 110. Throughout the entire run,

the OUI should be striving to gain contact through good search techniques.

Example #2-Radar Contact for Initial/Secondary Corrections

124