How is a Patch Test performed ROLL: - Flat / Smooth deep bottom - Opposite / Reciprocal lines - Same / Equal speeds LATENCY: - Flat bottom to an object or - Sloped bank feature - Same direction lines - Unequal speeds PITCH: - Flat bottom to an object or - Sloped bank feature - Opposite / Reciprocal lines - Same / Equal speeds Will be covered in detail at later session Emphasize that Patch Test is a QC function … NOT a QA operation as is a Performance Test Need be performed only periodically … equipment change. Not a daily event Test question … does not correct Heave YAW: - Flat bottom to an object or - Sloped bank feature - Parallel offset lines that are run in the Same direction - Same / Equal speeds 4/24/2017 HYPACK® Multibeam Training Seminar

HYPACK® Multibeam Training Seminar Patch Test Lines Single Head Latency: Line C D Same line and direction Differing speed, sloping bottom (Watch for settlement differences.) Pitch: Line C D Reciprocal lines, sloping bottom. Same Survey speed. Roll: Line A B Reciprocal lines, flat bottom. Same Survey speed. Yaw: Lines C D, E F Offset lines, sloping bottom. Will be covered in detail at later session Emphasize that Patch Test is a QC function … NOT a QA operation as is a Performance Test Need be performed only periodically … equipment change. Not a daily event Test question … does not correct Heave 4/24/2017 HYPACK® Multibeam Training Seminar

HYPACK® Multibeam Training Seminar Dual Head Patch Test Different geometry of the Heads requires that you overlap the Port and Starboard heads separately. Latency and Yaw still only require 2 lines. Roll and Pitch tests require 3 lines instead of 2. Yaw requires a slightly different spacing and Overlap scheme Some Dual Head systems in engineered mounting frames can be treated as single head. Nice graphic! Line separation? 1x depth at shallow end as you stated in another slide? 1½ x depth?—I thought that’s what Pat said. 4/24/2017 HYPACK® Multibeam Training Seminar

HYPACK® Multibeam Training Seminar Dual Head Patch Test Nice graphic! Line separation? 1x depth at shallow end as you stated in another slide? 1½ x depth?—I thought that’s what Pat said. HYPACK® Multibeam Training Seminar 4/24/2017

HYPACK® Multibeam Training Seminar Dual Head Patch Test Nice graphic! Line separation? 1x depth at shallow end as you stated in another slide? 1½ x depth?—I thought that’s what Pat said. HYPACK® Multibeam Training Seminar 4/24/2017

HYPACK® Multibeam Training Seminar Also keep in mind that your Boat Operator will make or BREAK your Patch Test. The more precise that the Boat Operator can run the Patch Test lines, the better the results will be. Therefore, the Boat Operator should run the Latency, Pitch, and Roll lines as close to Nadir beam over Nadir beam, from one pass to the next. 4/24/2017 HYPACK® Multibeam Training Seminar

HYPACK® Multibeam Training Seminar “Manually” cut Cross Sections Roll Test Latency Test Cut Perpendicular to Runline Cut On Top of Trackline Data Collection Direction Pitch Test Yaw Test Cut Parallel to and Between the Tracklines 4/24/2017 HYPACK® Multibeam Training Seminar Cut On Top of Trackline

How the Patch Test Works Numerical Method The cross sections are calculated at various angle offsets. For example; Pitch offset from -10 to 10 degrees in one degree steps. An error value is calculated at each offset. Error = average depth difference between cross sections. Minimum error is usually the correct offset. But not always. Good Fit Cross sections overlay well. Error is at the minimum point. Poor Fit Cross sections overlay poorly. Large error. 4/24/2017 4/24/2017 HYPACK® Multibeam Training Seminar 8 8

HYPACK® Multibeam Training Seminar The Patch Test Window Select Test Pick the tab corresponding to the test you want to run. Select Sonar Head For dual head systems, select head 1 or 2 Results Read test results here. Error Graph X axis is angle or time adjustment. Y axis is the error; difference between cross sections. Cross Sections Red is the first line, Green is the second. Vertical Adjustment Moves the first line up or down if needed. Override Select Previous or Next adjustment. 4/24/2017 4/24/2017 HYPACK® Multibeam Training Seminar 9 9

The New Patch Test Window 4/24/2017 HYPACK® Multibeam Training Seminar 10

HYPACK® Multibeam Training Seminar Patch Test Procedures The order that you collect your Patch Test data does NOT make any difference, but the order in which you process it, DOES… Order of Processing: Find the Latency offset first Apply Latency, then do the Roll test. Apply Latency and Pitch, then do the Pitch test. Apply Latency, Pitch, and Roll, then finish with the Yaw test. Also keep in mind that your Boat Operator will make or break your Patch Test. The more precise that the Boat Operator runs the Patch Test lines, the better the results will be. 4/24/2017 4/24/2017 HYPACK® Multibeam Training Seminar 11 11