World War II Japanese Aircraft
at the Old Colonia Airport, Yap State
Federated States of Micronesia



The aircraft at the old Colonia airport, and for that matter the airport and old dispersal area themselves, represent an historically important World War II military landscape. The overall landscape appears eligible for the U.S. National Register of Historic Places under at least two National Register Criteria (36 CFR 60.4). Association with World War II and the strategies of the two opposing forces makes the property eligible under Criterion A (association with significant historic events or patterns of events). As representative of a type of offensive airbase the landscape is probably eligible under Criterion C (representative of a type, representative of a distinguishable entity), as are its aircraft wrecks both individually and as contributing elements to the landscape. To the extent that study of the site can yield useful information about World War II and/or Japanese military aircraft construction during World War II, the airfield area is probably also eligible under National Register Criterion D (information significant in the study of history or prehistory). Site #s 1 and 4 – the “Kate” and the “Betty” – may be particularly significant both for the relative rarity of the aircraft they represent and for the important roles both bomber types played in World War II.

Further study of the landscape and its contributing elements – aircraft, revetments, artillery emplacements, taxiways, and the support facilities that must have been associated with the Japanese airfield could usefully supplement and enrich the existing historical record of World War II in the Pacific.


The wrecks have been torn apart to varying degrees by the original bombing and in some cases by later earthmoving and purposeful relocation of parts. The Betty (Site #4) retains an intact empennage but otherwise is badly fragmented. The Kate (Site #1) and the Zeros (Site #s 2, 3, 5, 6, and 7) typically have lost their engine areas back to the firewall, and their empennages and fuselage portions aft of the cockpit. Most engines remain on-site, however, as do some empennages. Some of the planes are still standing on one or both landing gears. Where wings are elevated from the ground they are typically broken near their midpoints, perhaps simply from corrosion, perhaps from a combination of bomb and strafing damage, corrosion, and human action (it is easy to imagine people standing on them and causing breakage after corrosion had weakened them).

All the wrecks are experiencing varying levels of deterioration due to corrosion. Deterioration is going on most rapidly where the metal of the wrecks is in contact with the ground. Typically these areas are severely deteriorated, while areas that remain permanently in the air are in better condition. Most parts that might be attractive to collectors have been removed from all the wrecks, and all are inscribed with graffiti.

We attempted to match the wrecks we examined with photographs taken of aircraft at the Colonia airport in the 1970s and 1980s, but were unable to make any definitive matches. Nevertheless, the differences between the aircraft depicted twenty to thirty years ago and those we examined are striking, and suggest that the planes are deteriorating and/or being disassembled and taken away quickly. Aircraft depicted in 1970s/80s photos typically have complete engines attached, complete empennages, and cockpit canopies, and are standing on their gear. The aircraft we examined obviously display none of these characteristics.

Management Options

Management of the area, and particularly of its aircraft wrecks, presents daunting challenges. The wrecks are obviously deteriorating, and will continue to do so unless protective measures are taken. Taking such measures would be expensive, however, and the payoff for taking them is uncertain. While the wrecks undoubtedly attract a certain number of tourists, it is probably rare for anyone to visit Yap for the sole purpose of looking at them, so it is difficult to argue that preserving them will benefit Yap in any financial way. They are historic relics, of course, but not every historic relic can be preserved forever. Every government, and indeed every individual, makes decisions every day about what to preserve and what to let go. The government of Yap is faced with such a decision concerning the wrecks at the old Colonia airport.

The following management options are available:

Do Nothing. If nothing is done – if the wrecks are simply left to deteriorate – they will continue to corrode and fall apart. People will continue to take parts away. We estimate that within twenty to thirty years, most of the wrecks will be reduced to piles of corroded parts on the ground, and eventually they will disappear altogether.

Preserve in Place, in Perpetuity. At the other end of the spectrum of possible management options is that of very active intervention to preserve the wrecks in place, in perpetuity. This would involve a complex of protective and conservation measures, such as building roofs over the wrecks, elevating them above the ground, treating them with protective chemicals and coatings, and policing them to prevent further theft and vandalism.

Preserve in a Museum Context. Another preservation alternative would be to move the wrecks, or some wrecks, to a museum or museum-like location where they could be covered, attended to, and conserved. Combined with the application of preservative chemicals and coatings this could extend an aircraft’s life more or less indefinitely, but at the cost of losing connection with the craft’s original location and the events that led to its condition. Museum conservation would also carry a heavy price tag in both the long and short runs.

Slow the Process of Decay. A number of relatively simple measures could be undertaken to slow the deterioration of the wrecks, though these measures would by no means halt decay altogether. Simply lifting the wreckage off the ground and placing it on piers or pilings while removing soil from it would reduce the rate of corrosion in the areas most subject to it. Building simple shelters over the planes, perhaps with post and thatch construction, would be a low-cost way to protect a plane from the elements. Such measures would detract somewhat from the sense of discovery that visitors can experience when visiting a wreck “in the wild,” and they would involve both initial and long-term commitment of funds, albeit fairly limited funds.

Give or Sell to Others. In the past some wrecks have been given or sold to parties in other countries (notably Japan) who sought them for purposes of conservation and exhibition or as sources of parts to use in historic aircraft reconstructions. This practice probably continues informally on a small scale today, and could be adopted as a formal preservation practice. Doing so would almost certainly require resolving questions of ownership. Arguments could be made for ownership of the wrecks by the Japanese, U.S., F.S.M., Yap State and Rull Municipality governments, as well as by the landowners on whose property they lie. Assuming ownership could be resolved, a sale and gift policy would also have to be harmonized with FSM and Yap State law pertaining to the removal of historic artifacts – a perhaps daunting but not insurmountable obstacle. Of course, the longer the wrecks are left to deteriorate, the less amenable they become to use as sale and gift items.

Document. Documentation is not a means of physically preserving historic sites, but it does preserve a record of them that can be used in interpretation and scholarly research, perhaps long after the sites themselves have disappeared. In the case of complex metal artifacts like aircraft, it is often the only feasible option for achieving any kind of preservation at all. Documentation might include more detailed maps than provided in this report, both of individual sites and of the airport and dispersal area in general, together with detailed photographic coverage and the results of historical and oral historical research.


We recommend a mixed strategy that applies different management standards to different wrecks, as follows:

  1. Documentation: A more detailed study should be completed of the airport area than we were able to provide in this year’s work. The entire area should be inspected in detail and all wreckage, structures, and bomb pits should be recorded and mapped. Background historical and oral historical research should be completed. The results should be published both in a technical report and in a popularly-oriented book or booklet.5
  2. Preserve in a Museum Context: If funds are available, the wrecks at Site #s 1, 5 and/or 7 might be appropriate for conservation in a museum context. Further documentation is likely to result in the identification of other aircraft that could be similarly preserved. The relatively intact cockpit area and empennage of the “Betty” at Site #4 might also be suitable for museum interpretation, provided their removal was balanced with appropriate documentation of their original context.
  3. Slow the Process of Decay: Of the sites surveyed in this assessment, Site #s 1, 5 and 7, if not moved to a museum location, may be the most amenable to preservation in the short term by raising the aircraft somewhat off the ground and constructing informal shelters over them – assuming that preservation in a museum context is not feasible, or as an interim measure until such an action can be taken. It is very likely that a detailed documentation program will reveal other aircraft equally or more appropriate for this kind of treatment. In each case, small-scale, inexpensive measures could be implemented to facilitate visitor access and public interpretation – with the understanding that facilitated access may speed deterioration by making it easier for people to remove or vandalize parts of the aircraft. Reasonable measures might include clearing and planting walkways as has been done at Site 4, and placement of simple interpretive signs, or perhaps creating self-guiding brochures in various languages.
  4. Do Nothing: No specific preservation actions are recommended for Site #s 2, 3, and 4, besides documentation as part of an overall study and, as noted above, possible removal of parts of Site #4 for museum interpretation. All three, however, are good places to allow visitors to experience the “discovery” of untreated, slowly decaying aircraft remains. There are probably many other such sites remaining to be discovered. With this option too, small-scale, inexpensive public interpretation development could be undertaken; self-guiding brochures might be particularly appropriate.
  5. Give or Sell to Others: Although we do not recommend that any of the wrecks recorded in this report be given or sold to other parties, we do believe that this option is one that the governments of Yap and the FSM need to consider, whose legal dimensions should be explored, and on which a concrete, balanced policy should be developed. Given the number of wrecks in the area, their condition, the near impossibility of preserving many or perhaps any of them over the long run, and the continuing interest in acquiring World War II artifacts by individuals and institutions on other countries, we think it would be inadvisable not to entertain the sale and gift option. One possibility to consider is that of bartering with a third party to take several aircraft and return one suitable for museum display. Although not as desirable as retaining and interpreting the aircraft in place, such an arrangement may in the long run become the only economically feasible means of making an aspect of Yap’s World War II history available for public appreciation.
  6. Preserve in Place in Perpetuity: We recommend none of the wrecks documented in this report for preservation in place in perpetuity. The potential costs of such preservation are simply too high, the outcome too uncertain, and the aircraft too deteriorated, to make such preservation a prudent use of scarce funds.


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