Day 555 [April 10/10] -- Calculating his ETA in Yokohama

Today's Report
April 10/10 0800 JST

11°34'S, 80°58'W (South Pacific Ocean, 1,769 nm from Valdivia)

Saito-san passed Lima during the day, as he boosted his DMG to 114 nm with improved winds mainly out of the SE.

It's been 15 full days since he left Valdivia, now nearly 1,750 nm distant on the chart. That translates to approx. 117 nm a day of DMG (actual miles of progress) toward Yokohama.

We have been discussing with Saito-san his ETA for Japan. It's certainly too early to get more than a very rough estimate, but here is our thinking:

As spring turns into early summer in the Northern Hemisphere, it is expected that he will encounter mostly favorable winds as he comes west and north. Especially as he approaches Japan, the winds will be prevailing out of the south in the next two months. In the dead of Japan's summer the winds virtually stop, but barring some sort of damage to the sails, he is expected to arrive before mid July, and likely before the end of June. This is also before the start of the main typhoon season in the North Pacific that runs from May to November, with Japan usually seeing the most visits, when they occur, beginning in August.

Before that, as he passes Hawaii he will pick up the tradewinds that blow a constant 15-20 kts out of the east. This should put him on a continuous starboard tack for several weeks, giving him some of the best sailing conditions of the entire voyage.

Boat condition:
The sails, while showing considerable wear, were repaired during the stop in Valdivia. The new genoa is in good shape and the staysail is holding up. The main is probably OK, although Saito-san says he has been having trouble with the battens and batten cars that hold the sail to the mast. He also has a repaired genoa for use as a spare if it becomes necessary to replace the headsail.

Since keeping the batteries charged is required to operate the vessel's hydraulic steering, the engine and generator are both needed, with the aux. generator being the main recharging source. The original deep-cycling marine batteries were replaced in Punta Arenas with heavy-duty truck batteries after no marine batteries could be locally sourced there. This was a calculated risk since truck batteries are not considered dependable for extended use at sea with frequent recycling. However, there was no other choice and for now they seem to be working well and are expected to last until Japan. He has been cautioned to not completely deplete them before the next recharge.

Adequate, with 3,500 liters on board when he left Valdivia. That's enough for at least 300 days of generator use @ 10 hours a day (1 liter/hr). Engine use at mid-range RPMs will reduce that by approx. 6 liters per hour of operation, with engine use expected to be minimal. If absolutely necessary, he can make a fuel stop along the way. Oil and fuel filters are holding up. He said the dirty fuel problem seems to be over.

Skipper's condition:
Happy, "no, not tired," and eager to finish. Saito-san's right arm is still stiff from his hatch injury in February, but he says he is able to do most things with it "if I am careful."

With these considerations, with little or no use of the ship's engine for propulsion, it can be expected that NBSDIII can average 116 -120 nm sailing the 9,000 remaining nautical miles to Yokohama. This computes to roughly 76 days, or an ETA of mid to late June. 

This morning Saito-san, when pressed to give an approximate landing date, said "I HOPE June 10."

We have just learned of another sailing vessel that has gone missing off the coast of Chile, possibly as a result of the massive earthquake in February. More on that tomorrow.

Distance in last 24 hours: 114 nm
Distance completed: 19,313 nm
To Yokohama: 8,986 nm, adjusted (distance remaining: 31.7%)
Heading: 300
Reported boat speed: 4.8 kt (day's average: 4.8 kt)
Weather: Overcast 
Temperature: 23.5° C
Barometer: 1008 hPa (steady)
Wind (from): Favorable 9-11 kt SSE -- expected to stay 13 - 15 kt mostly out of SE & SSE
Waves: 1.0 m
Current (from): 0.1 kt ENE
Engine rpms: 0 hrs
Generator: 10.0 hrs
Sails: Genoa 0%, staysail 100%, mainsail 1-pt reef

Position Map (click to enlarge)