The purpose of the Niku VII expedition is to conduct a thorough search of the underwater reef slope off the west end of Nikumaroro for surviving wreckage from Amelia Earhart’s Lockheed Electra. Nikumaroro, formerly Gardner Island, is an uninhabited coral atoll in the remote Phoenix Group, part of the Republic of Kiribati. The search area has been defined through interpretation of the available evidence. The search methodology and technology has been selected through consultation with the best available sources.

The objective of the expedition is to locate, identify, and photograph any and all surviving aircraft wreckage. No recovery of wreckage is contemplated. If wreckage is found, the imagery acquired on this expedition will be used to mount a subsequent recovery expedition equipped to safely retrieve and properly conserve whatever remains of NR16020. (Click on the small image at right to open a much larger version in a new window.)

The primary search area is based upon the hypothesis that the aircraft landed safely on the reef and remained there for several days before being washed over the reef edge by rising tides and surf at or near the point where the object on the reef – thought to be a detached landing gear assembly – appears in the 1937 Bevington Photo. (Click on the small photo at right to open a much larger version in a new window.)

Aircraft debris reportedly found and used by island residents in later years, and aircraft parts found by TIGHAR in the abandoned village strongly suggest that the aircraft broke up in the relatively shallow surf zone. No large components (engines, main beam, etc.) seem to have washed ashore, nor has any debris been seen during scuba-depth surveys of the reef slope. This expedition will test the hypothesis that the more massive parts of the aircraft traveled down the reef slope and came to rest in, as yet, unexplored depths.

The Niku VII expedition will have the capability to search with high-frequency side-scan sonar and take black & white photos down to a depth of 1,500 meters (4,921 ft). The expedition will be able to do detailed examination of sonar targets using high-definition video down to a depth of 1,000 meters (3,300 ft.). The available bathymetry indicates that the reef slope reaches that depth more than a mile out from the reef edge. If the hypothesis is correct, the wreckage should be well within the proposed search area. (Click on the small image at left to open a much larger version in a new window.)

Step 1. Map the search area using multi-beam sonar hull-mounted on the expedition vessel, supplemented in shallower areas by multi-beam sonar mounted on the Autonomous Underwater Vehicle (AUV). (The image at right opens a larger image in a new window.)
Step 2. Search the mapped area with side-scan sonar mounted on the AUV. The AUV is an unmanned, free-swimming robotic submersible that is programmed to carry out a particular search mission using its own onboard inertial navigation system. It is battery-powered and has a potential endurance of up to 24 hours, although our missions will be much shorter – probably no more than six hours. At the end of a mission the AUV is recovered, the data it has collected are downloaded, the batteries are swapped out for fresh ones, and the AUV is reprogrammed and launched for another mission. The data downloaded from the first mission are then analyzed and any targets of interest flagged for future investigation.			Side-scan sonar produces the clearest image when the target is on a flat sandy bottom. Our potential targets are not on a flat sandy bottom. This will be a difficult search.
Step 3. When the AUV has concluded its coverage of the search area, the collected sonar data have been analyzed, and a list of targets of interest has been compiled and prioritized, a Remote Operated Vehicle (ROV) will be deployed to investigate the targets. The ROV is tethered to the expedition vessel and is “flown” to the desired location by an operator in a dedicated control van installed aboard the expedition vessel. The ROV is equipped with sector-scan sonar to help re-locate the target. It has powerful lights and high-definition video cameras to provide real-time imagery to the operator. A manipulator arm can be used to remove obscuring objects. (The image at right opens a larger image in a new window.)