10. Operational Equipment, Navigation, Manipulators pg. 467

- Navigation: pg. 494

- Navigation needs surface support (1976 assumption)

Three Categories:

1. Surface Tracking

A. Marker Buoys: too crude

B. Active Sonar Ranging: use sonar to locate sub from surface ship

C. Pinger (Sub)-Hydrophone (Surf): No good

D. Pinger/Transponder (Sub) – Hydrophone Interrogator

i. Transponder Subsystem: Sub has a transponder that emits signal to interrogating transducer on surface ship

E. Short Base Line Systems: Considered most accurate at the time

i. Base Line: line btn two transmitters operating together to provide a line of position or line serving as basis for measurement of other lines.

ii. System used in bomb hunt with USNS MIZAR

iii. Four hydrophones spaced at known locations on hull and a timed pinger/transponder on the sub. Measure of different arrival times.

iv. Disadvantages: bad signals near surface, need for bigger surface ship.

2. Submerged Navigation:

A. Dead Reckoning:

i. Gyroscope for accurate heading (magnetic compasses are useless b/c affected by magnetic fields)

ii. Doppler Sonar: Used in the Johnson Sea Link. Still relies on Surface for general direction/location

B. Bottom Mounted Acoustic Systems:

i. Alvin:

a. Need to know the velocity of sound in water

b. Deploy 3 transponders that are synchronized w/ sub

ii. Didn’t work so well on Trieste and costs a lot.

Comments: Most of the systems and methods listed are too archaic. What does Alvin use today?