remove the limits = c(0, 360) since 0 and 360 will overlap:

library(ggplot2)

wake_loss_per_sector <- data.frame(
  sector = 1:12,
  wake_loss = c(16.48843, 17.59385, 19.19244, 27.17434, 26.13185, 10.95055,
                11.09595, 14.24783, 15.59619, 19.09893, 22.63984, 15.84240),
  angle = c(30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0)
)

# Plot
ggplot(wake_loss_per_sector, aes(x = angle, y = wake_loss)) +
  geom_col(width = 30, fill = "skyblue", color = "black") +
  coord_polar(start = -pi / 12) +
  scale_x_continuous(
    breaks = seq(0, 330, by = 30)
  ) +
  theme_minimal() +
  labs(x = "Angle (degrees)", y = "Wake Loss", title = "Polar Plot of Wake Loss by Sector")