Navigation Systems

5 free sample questions of the 60 in this topic. The full set is in the app.

1. Question 1

   What frequency range do ILS localizers operate on, and what spacing within that range?

   • A.108.10 to 111.95 MHz, ODD tenths only (e.g., 109.30, 110.10)
   • B.108.00 to 117.95 MHz, every tenth
   • C.118.00 to 136.975 MHz
   • D.75 MHz only
   Show answer & explanation

   Answer: A. 108.10 to 111.95 MHz, ODD tenths only (e.g., 109.30, 110.10)

   Per IFH Ch 9, ILS localizer frequencies span 108.10–111.95 MHz, transmitted on ODD tenths only. (Even-tenth frequencies in that band are reserved for VOR.) The aircraft's nav receiver selects either localizer or VOR depending on the tuned frequency.

   Source: FAA Instrument Flying Handbook (FAA-H-8083-15B) — Ch 9, Instrument Landing Systems (p. 9-36)

2. Question 2

   The localizer course is typically how wide (full-scale deflection on each side of centerline)?

   • A.5° total (±2.5° to each side of centerline)
   • B.10° total
   • C.20° total
   • D.Identical to a VOR course (±10°)
   Show answer & explanation

   Answer: A. 5° total (±2.5° to each side of centerline)

   Per IFH Ch 9, the localizer course is normally 5° total — full-scale deflection at 2.5° each side of centerline. This is 4× more sensitive than a VOR (which is ±10° = 20° full course). Maintaining no more than ¼-scale deflection keeps the aircraft aligned with the runway.

   Source: FAA Instrument Flying Handbook (FAA-H-8083-15B) — Ch 9, Localizer course width (p. 9-36)

3. Question 3

   How is an ILS localizer station identified by its Morse code identifier?

   • A.Three letters with NO prefix
   • B.Three letters, PREFIXED with the letter 'I' (two dots in Morse) — e.g., ISGF
   • C.A four-digit number
   • D.Only voice identification
   Show answer & explanation

   Answer: B. Three letters, PREFIXED with the letter 'I' (two dots in Morse) — e.g., ISGF

   Per IFH Ch 9, an ILS localizer is identified by a three-letter Morse code designator PRECEDED by the letter 'I' (two dots) — e.g., ISGF for Springfield, MO. The 'I' prefix distinguishes it from a VOR station, which has no prefix. The identifier confirms a working localizer.

   Source: FAA Instrument Flying Handbook (FAA-H-8083-15B) — Ch 9, ILS Localizer identification (p. 9-36 to 9-37)

4. Question 4

   What is the typical glideslope (GS) angle for an ILS approach?

   • A.Exactly 3°
   • B.Normally 2.5° to 3.5°, with 3° being typical (can be up to 4° for terrain/obstacle reasons)
   • C.5° to 7°
   • D.1° to 2°
   Show answer & explanation

   Answer: B. Normally 2.5° to 3.5°, with 3° being typical (can be up to 4° for terrain/obstacle reasons)

   Per IFH Ch 9, the GS projection angle is normally adjusted between 2.5° and 3.5° above horizontal, typically 3°. Where standard obstruction clearance cannot be obtained at the normal max, the GS angle may be increased up to 4°. The glide path is 1.4° thick — narrowing to a few feet at touchdown.

   Source: FAA Instrument Flying Handbook (FAA-H-8083-15B) — Ch 9, Glideslope (p. 9-36 to 9-37)

5. Question 5

   Does the ILS glideslope provide guidance on the BACK course?

   • A.Yes — GS guidance is bidirectional
   • B.No — GS radiates only in the direction of the final approach on the front course; back-course approaches are non-precision
   • C.Only if the runway has Cat II authorization
   • D.Only if the back course is specifically authorized
   Show answer & explanation

   Answer: B. No — GS radiates only in the direction of the final approach on the front course; back-course approaches are non-precision

   Per IFH Ch 9: 'Unlike the localizer, the GS transmitter radiates signals only in the direction of the final approach on the front course. The system provides no vertical guidance for approaches on the back course.' Back-course approaches are therefore non-precision (LOC BC).

   Source: FAA Instrument Flying Handbook (FAA-H-8083-15B) — Ch 9, Glideslope (p. 9-37)

55 more Navigation Systems questions are in the app, along with explanations and flashcards for every one.

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