---
kind: "unit"
title: "50"
title_heading: "War and National Defense"
key: "ch18"
level: "chapter"
label: "Chapter 18"
heading: "Air-Warning Screen"
release: "119-102"
url: "https://uscodex.org/usc/50/ch18"
sections_count: 4
---

# Chapter 18 — Air-Warning Screen

Title 50 — War and National Defense

## Sections

- [§491. Establishment and development of land-based air warning and control installations and facilities; extent of appropriation; procurement of communication services](/usc/50/491.md)
- [§492. Acquisition of land](/usc/50/492.md)
- [§493. Authorization of appropriations](/usc/50/493.md)
- [§494. Supervision and control of project](/usc/50/494.md)