31. Low Frequency Loran: Northeastern Chain. With reference to Paragraph No. 24 of the Board's meeting of November 20-21, 1947, the U.S. Air member reported concerning the modifications which the USAF had decided were required in the establishment of the northeastern chain of Low Frequency Loran stations. It will be recalled that the original plan was for one station on the eastern shore of Baffin Land, one on the western shore of Greenland, and one on the eastern shore of Greenland. It was pointed out that in view of the great difficulty at the preSent time of obtaining the approval of the DaniSh Government for the establiShment of the stations in Greenland, if the chain is to be established it would have to be established in Canada. The Chairman of the U.S. Section and the Secretary of the U.S. Section corroborated the U.S. Air member's²² understanding that it was not anticipated that the Danish Government could be persuaded during the next several years to agree to the establishment of Low Frequency Loran stations in Greenland.

General O'Donnell explained that a northeastern chain in Canada might be operated by using the easternmost station of the western chain as the westernmost station of the eastern chain, thus reducing the total number of stations involved. The chain previously discussed involved a station in Canada, the Survey for the western end of which had been approved by the Canadian Government. In view of the change now made necesSary, General O'Donnell expreSSed the hope that the queStion might now be reviewed by the appropriate Canadian authorities with a view to giving approval for the location and establishment of the northeastern chain in Canada as outlined above. The Canadian Air member said that a study of this question was now being made and that when this Study iS completed and the military requirements of LF Loran known, a decision on the question raised by General O'Donnell would no doubt be made.

The U.S. Air member then referred to the second serious difficulty which had caused modification of the original plans: The Atlantic City agreements of 1947, agreed to (hut not yet ratified) by both Canada and the U.S., had been construed as making unavailable 180 kcs. frequency in new Lf Loran stations and as imposing an obligation to convert existing stations to 90-110 kcs. frequency. He added that the U.S. Air Force therefore planned to establish the modified northeastern chain on the basis of the frequency agreed to at Atlantic City, 90-110 kcs. No equipment exists for this frequency, however, and it would be perhaps three years until it could be constructed and operational, Moreover, the use of this diffèrent frequency would mean that planes would have to he equipped with new type receivers. Again, whereas towers approximately 600 feet high are used in the LE Loran operations at 180 kcs., towers of approximately twice this height would be required for the frequency of 90-110 kcs. He noted that the additional equipment for the planes and the construction and installation of the 1200 foot towers would involve greatly increased costs and extraordinary difficulty in construction. Nevertheless, the USAF was at the moment in the process of placing contracts for construction of new equipment for the 90-110 kcs. frequency.

The Chairman of the Canadian Section expressed his misgivings over the modifications which it was suggested should he made in the equipment and towers, and inquired concerning the details of the commitments made at Atlantic City and the present status and future implications of these commitments. He suggested the possibility that the Canadian and U.S. delegations at Atlantic City might in good faith, but without fully appreciating the military necessity of LF Loran on the 180 kcs. frequency as presently planned, have made commitments involving the two Governments in great difficulty and expense. The Chairman of the U.S. Section stated that he shared these misgivings.

At the request of the Chairman of the U.S. Section, Mr. John S. Cross, Assistant Chief, Telecommunications Division, Department of State, kindly visited Patuxent²³ and explained to the Board in detail the background of the problem from the international and civil point of view and narrated the course of events at Atlantic City which resulted in international agreement for the band 90-110 kcs. for use by a pulse-type radio navigation aid. (A summary of Mr. Cross' remarks is attached hereto as Appendix No. 5.)i.

The Board, deeply concerned by the effect of the Atlantic City commitments on the LF Loran programme in the north, recommended that the military Loran committees of each country should as soon as possible determine the requirements, from the military point of view, of LF Loran in the north and should assess the effect of the Atlantic City commitments on present plans and operations. The Board further recommended that if the military Loran committees should find that efforts should he made to modify the commitments made by the two Governmentsat Atlantic City, the matter should be put before the highest telecommunications authorities in the two Governments for their consideration. The Board regards this as a matter of urgency and requested a full report to be made at its next meeting by the Air members.

²²acheson était président, A.B. Foster, secrétaire et le major-général E. O'Donnell représentant de 1'armée de l'air, Commission permanente canado-américaine de défense (CPCAD).
Dean Acheson was Chairman, A.B. Foster was Secretary and Maj-Gen E. O'Donnel1 was Air

²³ La reunion de la Commission permanente canado-américaine de défense (CPCAD) eut lieu au centre d'essai aéronaval de Patuxent.
The PJBD meeting was held at Patuxent Naval Air Test Centre.