In Michelson's Pilot House


When underway, Michelson's pilot house, or bridge, was the domain of the watch officer (mate) and quartermaster, or helmsman, an able seaman (AB). Their view was limited. Just five portholes provided forward visibility. Doors on either side of the pilot house led to the bridge wings. There, the mate made celestial observations and took gyro compass bearings when close to shore. 
 

Michelson's bridge was equipped with telemotor hydraulic steering, built by a company in Beacon, New York that prior to WWII had made commercial baking machinery. According to the Dutchess Tool Company every Liberty Ship and Victory class vessel was fitted with their steering apparatus.

Hydraulic tubes extended back from the telemotor helm on the bridge to the aft steering room, where the helmsman's port/starboard movement of the wheel operated something called a six way valve. This device controlled the amount of hydraulic pressure applied to two large rams, each with cylinders at either end. Both rams were tied to the ship's rudder shaft. Two electrically driven pumps supplied the necessary pressure. Provision was made for emergency steering aft near the stern. While the pilot house telemotors were the same on Liberty and Victory ships the actual steering machinery differed. Steam power was used to turn the rudder on Liberty ships.

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A gyrocompass repeater

Back in the pilot house, the helm was located at the center line toward the rear, allowing the AB on watch to lean against the rear bulkhead, while standing on a small raised platform or mat. Two compasses, a magnetic one with iron compensating balls was immediately forward of the wheel and a gyrocompass repeater was installed just to the left.

A classic looking engine order telegraph was bolted to the deck and an inclinometer, something like a plumb bob, indicated how far the ship rolled. A rudder angle indicator was on the forward bulkhead.

Engine order telegraph
Also present on the bridge were two surface search radar screens as well as phones, electrical switches, intercoms, speaking tubes, storage for signal flags and a chair reserved for the captain. A pass through window provided communication from chart room to the bridge. Access to the pilot house was through a door (port side, rear) into the chart room and the top of stairs (a/k/a ladder) leading to the captain's cabin one deck below. 

The bridge was kept dark at night for visibility's sake. It was generally regarded as off limits to anyone not on watch without business being there.


Directly behind the bridge, the chart room (or chart house) was where the mates consulted their charts, plotting courses as well as visual and celestial position fixes. They had a big chart table with built in cabinet for three mechanical chronometers, essential for determining longitude. A Loran A receiver, radio direction finder and fathometer were just about all the electronics navaids present. Customarily, each mate brought his own sextant.

Being the ship's navigator, the chart room was the second mate's office. There he corrected the large inventory of charts using the Notices to Mariners. The chronometers were wound regularly and errors tracked. Available were navigation reference books of every description. Some were:

  • Nautical Almanac
  • Sight reduction tables
  • Logarithmic tables
  • Tide tables
  • Light lists (lighthouses)
  • Sailing directions
  • House flags and stack insignia
  • Bowditch's American Practical Navigator
Navigation by celestial and visual sightings plus dead reckoning was the norm for the 1960s as it had been for decades before. All of this seems archaic today. Now with GPS,  inertial systems, electronic charts and digital radar, along with the autopilot, navigating the seven seas is a lot less complex.

Curiously, just a few feet away in the Survey Control Center the navy and oceanographic guys were plotting positions with far greater accuracy using a computer and radio navigation. However, being that the deck officers were responsible for the ship's safety they rarely relied on our information. 


Only when Michelson was actively surveying did the oceanographer on duty actively direct the ship's movements. He then had "the conn".