Japanese Type A Kō-Hyōteki Mini Submarine (HA-16)

A Japanese Type A Kō-Hyōteki Miniature Submarine (like HA-16) discovered in Keʻehi Lagoon in 1960. Image courtesy of Naval History and Heritage Command. Download largest version (jpg, 300 KB).

Background

Discovered in 2005 during an oil and gas survey and identified as Site 15377 by the Bureau of Ocean Energy Management (BOEM), this wreck site was explored for the first time on December 9, 2017, during an expedition led by NOAA Ocean Exploration aboard NOAA Ship Okeanos Explorer. Remotely operated vehicle (ROV) Deep Discoverer — equipped with an Insite Pacific Zeus Plus camera capable of collecting high-definition footage — was used to document the site, which is at a depth of approximately 700 meters and is 32 meters long and 10 meters wide.

The remains of the Japanese Type A Kō-Hyōteki Miniature Submarine (HA-16) rest where it was dumped on the seafloor in deep water off Oahu, Hawaiʻi. Image courtesy of NOAA Ocean Exploration, Shakedown, Calibration, and Testing in the Main Hawaiian Islands.
Download largest version (jpg, 1.07 MB).

Exploration

The Hawaiʻi Undersea Research Laboratory found and explored the three pieces of the HA-16 mini submarine south of Pearl Harbor during submersible dives in 1992, 2000, and 2001 (the stern section, midsection, and bow, respectively). On December 7, 2016, NOAA Ocean Exploration and NOAA’s Office of National Marine Sanctuaries explored HA-16 on the 75th anniversary of the attack on Pearl Harbor during a shakedown expedition aboard NOAA Ship Okeanos Explorer. Remotely operated vehicle (ROV) Deep Discoverer — equipped with an Insite Pacific Zeus Plus camera capable of collecting high-definition footage — was used to document the site, which is at a depth of approximately 500 meters.

Modeling

This model of HA-16 is based on the ROV dive footage from timestamps 21:20 to 22:00 for the midship section, 22:15 to 22:50 for the stern section, and 23:15 to 23:55 for the bow section. This footage was exported into 2,321 images using VLC Player. The footage collected during exploration of HA-16 was not intended for photogrammetry. So, to address alignment issues, three individual models were made and then stitched together in Rhinoceros 8 and uploaded to Construkted Reality.

Model Navigation Basics

Desktop:

To zoom in and out: Use the scroll wheel on the mouse.
To move around: Left click on the model with the mouse and drag.
To rotate: Right click on the model with the mouse and drag.

Mobile Devices:

To zoom in and out and rotate: Pinch
To move around: Tap and drag any direction.

Photogrammetry model of the Japanese Type A Kō-Hyōteki Miniature Submarine (HA-16) developed by Raymond Phipps, NOAA Ocean Exploration explorer-in-training, July 6, 2023. Model courtesy of NOAA Ocean Exploration, Shakedown, Calibration, and Testing in the Main Hawaiian Islands.