I start to read AIM and AC90-105A about alternate considerations.If I have GPS(TSO-129 let’s say),Can I file based on a GPS-based IAP at the alternate airport,and my alternate airport only has GPS approach?
See 9.5 of the referenced document:
9.5 Contingency Planning for Alternate Airport.
9.5.1 Alternate Airport Considerations. For the purposes of flight planning, any required alternate airport must have an available instrument approach procedure (IAP) that does not require the use of GPS. This restriction includes conducting a conventional approach at the alternate airport using a substitute means of navigation that is based upon the use of GPS. For example, these restrictions would apply when planning to use GPS equipment as a substitute means of navigation for an out-of-service very high frequency omni-directional range (VOR) that supports an instrument landing system (ILS) Missed Approach Procedure (MAP) at an alternate airport. In this case, some other approach not reliant upon the use of GPS must be available. This restriction does not apply to pilots with navigation systems meeting the requirements below.
188.8.131.52 For flight planning purposes, TSO-C129( ) and TSO-C196( ) equipped users (GPS users) whose navigation systems have fault detection and exclusion (FDE) capability, who perform a preflight RAIM prediction at the airport where the RNAV (GPS) approach will be flown, and have proper knowledge and any required training and/or approval to conduct a GPS-based IAP, may file based on a GPS-based IAP at either the destination or the alternate airport, but not at both locations. At the alternate airport, pilots may plan for applicable alternate airport weather minimums using:
- Lateral navigation (LNAV) or circling minimum descent altitude (MDA);
- LNAV/vertical navigation (VNAV) decision altitude (DA), if equipped with and using approved barometric vertical navigation (baro-VNAV) equipment;
- RNP 0.3 DA on an RNAV (RNP) IAP, if they are specifically authorized users using approved baro-VNAV equipment and the pilot has verified RNP availability through an approved prediction program.
Note: If the above conditions cannot be met, any required alternate airport must have an approved IAP other than GPS that is anticipated to be operational and available at the ETA, and which the aircraft is equipped to fly.
184.108.40.206 Pilots with WAAS receivers, TSO-C145( ) or TSO-C146( ), may flight plan to use any IAP authorized for use with their WAAS avionics as the planned approach at a required alternate, with the following restrictions. When using WAAS at an alternate airport, flight planning must be based on flying the RNAV (GPS) LNAV or circling minima line, or minima on a GPS approach procedure, or conventional approach procedure with “or GPS” in the title. Properly trained and approved, as required, TSO-C145( ) and TSO-C146( ) equipped users (WAAS users) with and using approved baro-VNAV equipment may plan for LNAV/VNAV DA at an alternate airport. Specifically authorized WAAS users with and using approved baro-VNAV equipment may also plan for RNP 0.3 DA at the alternate airport as long as the pilot has verified RNP availability through an approved prediction program. Code of Federal Regulation (CFR) Part 91 nonprecision weather requirements must be used for planning. Upon arrival at an alternate, when the WAAS navigation system indicates that LNAV/VNAV or localizer performance with vertical guidance (LPV) service is available, then vertical guidance may be used to complete the approach using the displayed level of service.