Magnum's "Home From The Sea" Drift Timeline
Posted: Wed Jul 29, 2015 4:49 pm
As a kayaker, I thought it would be interesting to create a map and timeline of how far and where Magnum drifted in "Home from the Sea". I have created a timeline using a starting point of the episode's dialogue, where Magnum can see Rick's boat, so he's only a few yards from it. At that time Magnum says he has been in the water 20 hours. Rick's radio conversation with Higgins indicates he is in the Molokai Channel off Koko Head, and it is an hour before sunrise. Sunrise in Honolulu on Tuesday, July 5, 1983 was at 5:54 AM. Working backwards from that time, here is the timeline:
Monday, July 4, 1983
8:54 AM - Magnum is three miles offshore of Oahu, and has just started his paddle, when he is capsized by a couple of turkeys.
1:54 PM - Magnum has been in the water for 5 hours.
2:54 PM - Magnum has been in the water for 6 hours.
9:04 PM - Magnum has been in the water for 12 hours and 10 minutes, when he is bumped by "Herman" the shark.
Tuesday, July 5, 1983
4:54 AM - Magnum has been in the water for 20 hours, and he hears Rick in the King Kamehameha II yacht. Rick is in the Molokai Channel off Koko Head, and it is 1 hour until sunrise.
5:54 AM - Magnum is rescued after 21 hours in the water.
I found a source that provides information on currents around where Home From The Sea took place:
http://www.pacioos.hawaii.edu/currents/model-oahu/
I assumed there might be a seasonality to currents in that area, so I looked at the 3 years of July 4 currents they had on record. Here is what I've concluded:
If the fictional Robin's Nest was in the same place the actual Robin's Nest was, near Waimanalo Beach, there is absolutely no way Magnum could have paddled out from the estate's tide pool on the morning of the 4th, he'd have to be drifting against the prevailing currents to end up off Koko Head. He'd have had to started somewhere near Honolulu for the current to carry him there.
The currents don't start consistently heading in the direction of Koko Head until about Diamond Head.
The currents about 3 miles out between Diamond Head and Koko Head run about 0.3 kts. The currents don't speed up that close to Oahu until you get right to the Koko Head point, where they max out a little above 1.5 kts.
Being in the water for 21 hours in 0.3 kt currents would carry you 6.3 nautical miles, which is about 7.2 statute (regular) miles. The as-the-crow-flies distance between Diamond Head and Koko Head is about 7 miles.
So the conclusion is a workable drift would have Magnum driving or being driven to Diamond Head State Park, paddling south from the point 3 miles, almost immediately getting capsized, and being carried by the current across Maunalua Bay before being rescued off Koko Head.
Something to think about, an average swimmer can swim about 2 miles an hour, an experienced swimmer in good condition, which Magnum was, can swim 4 miles an hour, which is about 3.5 kts. From where he was when he realized he was separated from the surfski, if Magnum had just started swimming toward shore, and lets say he paced himself by only going 1.75 kts, and he wouldn't even be fighting but swimming perpendicular to a 0.3 kt current, which is just sweeping him along protected Maunalua Bay, and then once he gets close enough, about 2 miles east of Diamond Head the current actually would be pushing him towards the shore. Magnum should have been able to pretty easily swim to shore, and was never in any real danger.
Monday, July 4, 1983
8:54 AM - Magnum is three miles offshore of Oahu, and has just started his paddle, when he is capsized by a couple of turkeys.
1:54 PM - Magnum has been in the water for 5 hours.
2:54 PM - Magnum has been in the water for 6 hours.
9:04 PM - Magnum has been in the water for 12 hours and 10 minutes, when he is bumped by "Herman" the shark.
Tuesday, July 5, 1983
4:54 AM - Magnum has been in the water for 20 hours, and he hears Rick in the King Kamehameha II yacht. Rick is in the Molokai Channel off Koko Head, and it is 1 hour until sunrise.
5:54 AM - Magnum is rescued after 21 hours in the water.
I found a source that provides information on currents around where Home From The Sea took place:
http://www.pacioos.hawaii.edu/currents/model-oahu/
I assumed there might be a seasonality to currents in that area, so I looked at the 3 years of July 4 currents they had on record. Here is what I've concluded:
If the fictional Robin's Nest was in the same place the actual Robin's Nest was, near Waimanalo Beach, there is absolutely no way Magnum could have paddled out from the estate's tide pool on the morning of the 4th, he'd have to be drifting against the prevailing currents to end up off Koko Head. He'd have had to started somewhere near Honolulu for the current to carry him there.
The currents don't start consistently heading in the direction of Koko Head until about Diamond Head.
The currents about 3 miles out between Diamond Head and Koko Head run about 0.3 kts. The currents don't speed up that close to Oahu until you get right to the Koko Head point, where they max out a little above 1.5 kts.
Being in the water for 21 hours in 0.3 kt currents would carry you 6.3 nautical miles, which is about 7.2 statute (regular) miles. The as-the-crow-flies distance between Diamond Head and Koko Head is about 7 miles.
So the conclusion is a workable drift would have Magnum driving or being driven to Diamond Head State Park, paddling south from the point 3 miles, almost immediately getting capsized, and being carried by the current across Maunalua Bay before being rescued off Koko Head.
Something to think about, an average swimmer can swim about 2 miles an hour, an experienced swimmer in good condition, which Magnum was, can swim 4 miles an hour, which is about 3.5 kts. From where he was when he realized he was separated from the surfski, if Magnum had just started swimming toward shore, and lets say he paced himself by only going 1.75 kts, and he wouldn't even be fighting but swimming perpendicular to a 0.3 kt current, which is just sweeping him along protected Maunalua Bay, and then once he gets close enough, about 2 miles east of Diamond Head the current actually would be pushing him towards the shore. Magnum should have been able to pretty easily swim to shore, and was never in any real danger.
