point at which the vertical angle is 0.860 to 0.900 and 1.100 to 1.140.
II. The DDM beneath the ILS glide path shall increase as steadily as possible for decreasing angles until a value of 0.22 DDM is reached.
III. The vertical angle at which a value of 0.22 DDM is reached below the ILS glide path shall be not less than 0.300. However, if this value is reached at an angle greater than 0.450, the DDM value shall not be less than 0.22 for angles down to the angle of 0.450.
(ｪｧ)The vertical angle at which a value of 0.0875 DDM is reached beneath the ILS glide path shall not deviate in excess of the value obtained by deducting the vertical angle of the point concerned from 0 and multiplying this figure by the following values:
I. For Facility Performance Category I-ILS equipment: 25/100.
II. For Facility Performance Category II-ILS equipment: 20/100.
III. For Facility Performance Category III-ILS equipment: 15/100.
(ｪｨ)Two sets of transmitters shall be provided so that either one can be used by switching over when necessary.
(ｪ｡ｪ)A dummy antenna shall be provided.
(ｪｪ)A standby isolated power unit shall be provided.
(ｪｪ｡)Monitoring equipment shall be provided.
(ｪｪ｢)The monitoring equipment shall consist of an automatic monitoring system which is designed to provide to the designated control points as soon as possible, within a limit of 6 seconds for Facility Performance Category I-ILS glide slope equipment or 2 seconds for Facility Performance Category II-ILS glide slope equipment and Facility Performance Category III-ILS equipment, when any of the following situations arise, and with the additional function of automatic and simultaneous switchover to the standby transmitter, and the further function of terminating the transmissions of the glide slope equipment when said situations or malfunctions persist even after switching over to the standby equipment:
I. When the angle between the glide path and the horizontal shall deviate from a range between 0.925 times and 1.10 times the established value.
II. When the vertical angle at which the DDM is 0.0875 below the glide path deviates from the following values.
｢)For Facility Performance Category II-ILS equipment, the value obtained by multiplying the value obtained by reducing the vertical angle at the established point from 0 by 25/100.
III. When the DDM decreased below 0.175 at the lower limit of the rated coverage of the glide slope.
IV. For the glide slope emitting one carrier, when the antenna output power decrease below 50 percent the normal value in the case of compliance with the standards from (･｣) to (ｪｦ) inclusive and for the glide slope emitting dual carriers, when the antenna output power decrease below 80 percent the normal
