1-1-22. Precision Approach Systems other than ILS, GLS, and MLS
Approval and use of precision approach systems other than ILS, GLS and MLS require the issuance of special instrument approach procedures.
b. Special Instrument Approach Procedure
1. Special instrument approach procedures must be issued to the aircraft operator if pilot training, aircraft equipment, and/or aircraft performance is different than published procedures. Special instrument approach procedures are not distributed for general public use. These procedures are issued to an aircraft operator when the conditions for operations approval are satisfied.
2. General aviation operators requesting approval for special procedures should contact the local Flight Standards District Office to obtain a letter of authorization. Air carrier operators requesting approval for use of special procedures should contact their Certificate Holding District Office for authorization through their Operations Specification.
c. Transponder Landing System (TLS)
1. The TLS is designed to provide approach guidance utilizing existing airborne ILS localizer, glide slope, and transponder equipment.
2. Ground equipment consists of a transponder interrogator, sensor arrays to detect lateral and vertical position, and ILS frequency transmitters. The TLS detects the aircraft's position by interrogating its transponder. It then broadcasts ILS frequency signals to guide the aircraft along the desired approach path.
3. TLS instrument approach procedures are designated Special Instrument Approach Procedures. Special aircrew training is required. TLS ground equipment provides approach guidance for only one aircraft at a time. Even though the TLS signal is received using the ILS receiver, no fixed course or glidepath is generated. The concept of operation is very similar to an air traffic controller providing radar vectors, and just as with radar vectors, the guidance is valid only for the intended aircraft. The TLS ground equipment tracks one aircraft, based on its transponder code, and provides correction signals to course and glidepath based on the position of the tracked aircraft. Flying the TLS corrections computed for another aircraft will not provide guidance relative to the approach; therefore, aircrews must not use the TLS signal for navigation unless they have received approach clearance and completed the required coordination with the TLS ground equipment operator. Navigation fixes based on conventional NAVAIDs or GPS are provided in the special instrument approach procedure to allow aircrews to verify the TLS guidance.
d. Special Category I Differential GPS (SCAT-I DGPS)
1. The SCAT-I DGPS is designed to provide approach guidance by broadcasting differential correction to GPS.
2. SCAT-I DGPS procedures require aircraft equipment and pilot training.
3. Ground equipment consists of GPS receivers and a VHF digital radio transmitter. The SCAT-I DGPS detects the position of GPS satellites relative to GPS receiver equipment and broadcasts differential corrections over the VHF digital radio.
4. Category I Ground Based Augmentation System (GBAS) will displace SCAT-I DGPS as the public use service.
|Aeronautical Information Manual (AIM) — Chapter 1|
| 1-1-1 - 1-1-2 - 1-1-3 - 1-1-4 - 1-1-5 - 1-1-6 - 1-1-7 - 1-1-8 - 1-1-9 - 1-1-10 - 1-1-11 - 1-1-12 - 1-1-13 - 1-1-14 - 1-1-15 - 1-1-16 - 1-1-17 - 1-1-18 - 1-1-19 - 1-1-20 - 1-1-21 - 1-1-22|
1-2-1 - 1-2-2 - 1-2-3