Chapter 20. Air Traffic Service Routes ▶ Section 1. General 20-1-1. PURPOSE 20-1-2. CONTROLLED AIRSPACE 20-1-3. DESIGNATION OF ATS ROUTES 20-1-4. RESPONSIBILITIES 20-1-5. ROUTE IDENTIFICATION 20-1-6. BASE ALTITUDES 20-1-7. MINIMUM EN ROUTE ALTITUDES 20-1-8. PROCEDURAL REQUIREMENTS 20-1-9. ACTION TO RAISE BASE OF TRANSITION AREAS ▶ Section 2. Flight Inspection Requirements 20-2-1. FLIGHT INSPECTION REQUESTS 20-2-2. REQUEST FOR FLIGHT INSPECTION DATA 20-2-3. FLIGHT INSPECTION REPORT 20-2-4. FLIGHT INSPECTION DATA DISTRIBUTION ▶ Section 3. Federal Airways 20-3-1. DEFINITION 20-3-2. NAVAID SPACING 20-3-3. VERTICAL AND LATERAL EXTENT 20-3-4. WIDTH REDUCTIONS ▶ Section 4. Jet Routes 20-4-1. DEFINITION 20-4-2. NAVAID SPACING 20-4-3. JET ROUTE WIDTH ▶ Section 5. Area Navigation (RNAV) Routes 20-5-1. PURPOSE 20-5-2. RNAV ROUTE CRITERIA 20-5-3. WAYPOINTS 20-5-4. LATERAL PROTECTED AIRSPACE CRITERIA FOR RNAV EN ROUTE SEGMENTS 20-5-5. RNAV ROUTE DESCRIPTIONS