Is GPS Navigation accurate enough to be GPS Piloting?

I woke up to bouncing off the wall in my rack. When I went to sleep two hours ago, we were close to the traffic separation scheme. If we were rocking and rolling like this in the mouth of the channel, it was going to be a long day. Although I was a Boatswains Mate, the thought of how our Navigation Detail was going find the way up the Delaware River in this weather weighed heavily on my mind. The route north on the Delaware between New Jersey and Delaware to Philadelphia Naval Shipyard took six hours on a good day.

Today was different, there was a Nor'easter coming ashore on the Delaware shore later today, we had to find refuge or risk riding out the storm at sea with mechanical problems. Anchoring out was not an option, if we dragged anchor in the channel, we would risk being a permanent, expensive fixture of the shoreline. It turns out we were going to use technology, one of the Navy’s brand new GPS navigation systems, to muscle through a think blanket of fog, wind and rain to make it home safely.

Since the sea and anchor detail was so long and risked turning men to icicles in the biting January wind. so, we took turns freezing on the foc's'le. I was heading up to the bridge for my turn at warmth when I saw this wall of rain and fog rolling towards us from New Jersey. We were still in the widest part of the channel, so the Captain ordered the anchor dropped. Just as a car pulls off the highway, we dropped the hook to figure out we were going to do.

The Captain, the Navigator and the Master Chief Quartermaster huddled over the chart table in hushed voices. After a few moments, of hushed, lively discussion, they seemed to come to an agreement.

The Captain, walked away from the chart table saying to the two sternly, “You two better make it work.”

The Captain stood in the middle of the bridge and began his impromptu brief.

"Alright gang," pausing until all eyes were on him, "here is the deal, we have to make it to Philly this afternoon, we can’t turn around because we will hit the storm full on and with our engine problems life would not be good, we can’t anchor here because the wind is picking up and we will probably not stay anchored for very long.

We were hanging on to his words in complete suspense, "we are going to put that new Global Positioning System to the test, we are going to navigate the channel using this system and radar." He paused to emphasize the seriousness of the situation, "Is everyone up to it?"

As far as we knew, no one had really done this six-hour passage, without seeing where we were going, like a submarine in thirty feet of water or an aircraft landing using instruments only.

The Navigator leaned over to the Master Chief and whispered, "I hope this works."

The crusty Master Chief was busy plotting the trek all the way up to the pier at the Shipyard as he replied, "me too."

Global Positioning Systems were in thier infancy, there may have 10 satellites at the time, we had just received this unit about the size of a trashcan above the chart table. It was actually an aircaft global positoning system fitted for shipboard life. Yes, it looked out of place on the bridge. Back then the signal was "dithered", which meant it was accurate to a few feet with the signal encrypted, we would need that accuracy.

With whole lot of luck and a little bit of skill, we pulled up the anchor in the freezing rain and started making way. I was the helmsman, usually just happy not to be on the anchor detail, but today I had to be on top of my game.

We proceeded up the channel with complete precision and accuracy, the orders were crisp and on the mark. The Master Chief would count off, "Come to course 328 in 5…4…3…2…1 – mark!" This was followed by the Conning Officer distinctly pronouncing, "Right Standard Rudder, come to course 328!" I executed the turn. We repeated this a couple of hundred times in virtual blindness.

We slowed to where our pier should have been, the Captain stoically asked everybody not expecting an answer, "OK, where is it?" As if someone had moved the pier.

The Master Chief said with pride, “Right there.”

The light at the end of pier and the line handlers came in to view as we silently slipped into the pier.

We could not have done it better on bright spring day. When all the lines were doubled up the Captain came back on the bridge and simply said, "Beers on me!"

That was all the gratitude I needed.