Saturday, July 9, 2016

July 9  Miles Traveled

I was going to summarize the trip with things like number of countries visited, but if you're interested in that you can count them up yourself by reviewing the blog.  The one thing I can report on is miles traveled.

Note: This turned out way more analytical than I had expected.  

Here's the executive summary:
Ship's "log" miles traveled: 46,501 nautical miles.  That's not right, it should be about 48,500.  The Bradleys traveled about 55,900nm because we took airplanes and buses and foot travel that the boat couldn't.

Back to the blog post:
Oceania distributed a 4-sheet paper entitled Nautical Miles Traveled that listed the miles traveled between ports.  They list 90 mileage figures for a total of 91 ports, with Miami repeated at the end.



It says Insignia traveled 46,501 nautical miles around the world.  That's a lot of wandering, since the circumference of the earth is 24,901 statute miles, or 21,638 nautical miles.  (When you drive on the highway, it's statute miles of 5280 feet each and speed is measured in miles per hour, mph.  When you sail you travel in nautical miles of 6000 feet each, and speed is nautical miles per hour, knots.  If everybody adopted the metric system we wouldn't have this problem.)

Unfortunately, their numbers are wrong.  I sure hope they didn't use those numbers to calculate when to stop for gas (bunkering is the quaint verb they use for "filling up").  By my guess they're about 1000nm too low, and the real number should be more like 47,500nm. 

There are some obvious mistakes.  The distance from Brisbane to Sydney is listed at 48nm when it's more like 550nm.  I'm guessing that the "log" was created before the actual trip, and when there were changes in the ports visited (you will recall that Newcastle was scrapped because of a harbor protest on our scheduled day so Oceania substituted Brisbane) they got the ports right but not necessarily the distances.  (In this specific case they did get the Townsville to Brisbane leg pretty close, although 50nm shorter than I measured it.)

Also, based on my measurements of actual distances traveled (see below) I can also argue that most of the Insignia log numbers are too low by 5% on about half of the legs.  Some are remarkably close to my measurement, others are off.  So we can probably add another 1000nm for "plan vs. actual" distances traveled.

 As for the Bradleys, we traveled 55,900nm or 64,300 statute miles on our trip around the world. 

I carried a hand-held GPS unit with me almost all the time, a Magellan Triton 400.  I left home with several of them.  A good thing since one of them failed spectacularly in mid-February.  The map below is the composite of 224 individual tracks I saved with the GPSes.


I carried it on our excursions, and got accurate route maps.  Here's an example, our VIP tour of military bases on Oahu. I used some other track maps earlier in this blog.


I only had to "recreate" 3 or 4 tracks due to GPS failure or operator error.  Those may not be as accurate, but a good guess as to the mileages covered.  I did have the GPS sitting out on the veranda whenever we were sailing, so I got those tracks also.  Sometimes there were interesting events.  Here's the run from Brunei to Borneo.

The "nose" in the middle of the track was apparently to get away from coastal waters so they could dump the grey and black water holding tanks.  (At every lifeboat drill I talked to one of the ship's officers and asked him these kind of questions.  He was very accommodating.)  The outward extension is about 30nm.  Since my track was 417nm and their log was 377nm I think that they listed the planned rather than actual mileage.

We also didn't travel everywhere the ship went.  We took six overnight trips (Phinda in SAfrica (1 night), Taj Mahal (3), Bagan in Myanmar (1), Angkor Wat in Cambodia (2), Beijing (3) and Hanoi (1)) , spending a total of 11 nights away from the boat.  So we racked up air miles and bus miles that people on the boat didn't.  Conversely, the boat traveled while we were gone.  We eventually caught up, going a different route, so our mileage was different.

Finally, all of our shore excursions weren't in the ships log.  My guess is over 7000nm greater than the boat actually traveled.  About 4Knm were in the overnights, the remaining 3K in run-of-the-mill bus shore excursions.  Our trip to Amboseli Park in Kenya was about 600 air miles.  That was just one of our 56 shore excursions.  However, on Rangiroa we we only walked about 3 miles while we were off the boat.  

No matter how you measure it, it was a long way but it had to be to pack everything into it.  My spreadsheet is available for anyone wishing to check my work.






3 comments:

Erin said...

You're probably on the money about the miles traveled document having been prepared in advance of the voyage, and didn't account well for the deviations en route. Did they have a Nav Channel on TV ... showing information such as distance from and distance to ports, temps, and coordinates. I like to check this information at the beginning of each day.

Sarah said...

Well, that was an impressive summary, Dr. Bradley. I want to hear more details about the magellan failing "spectacularly". Unless there was smoke/visible flames involved, it couldn't have been *that* exciting. :)

I told the munchkin you traveled 60k+ miles and she was impressed.

diveloonie said...

Hi, I enjoyed reading your blog. We hope to do a world cruise when my husband retires. If you have cruised a lot and done some other lines, how would Oceania compare? The food, the ship, entertainment etc.
I like Crystal so far the best, but still researching.
Thanks!