Why did the US Air Force's RQ-170 Sentinel stealth reconnaissance drone have a grill covering its engine inlet instead of using an inlet like the B-2 Spirit? - Quora
Lockheed Martin RQ-170 Sentinel 🇺🇸🇺🇸🇺🇸 Stealth UAV for CIA - YouTube
Lockheed Martin RQ-170 Sentinel by bagera3005 on DeviantArt | Lockheed, Stealth aircraft, Aircraft design