Why the XF-84H Thunderscreech Made Its Own Crews Sick

In 1955, at Edwards Air Force Base, ground crews towed one experimental fighter far out onto the dry lakebed before they dared start its engine. The Republic XF-84H had a twelve-foot, three-bladed propeller whose tips spun faster than sound while the plane stood still. Ground crews reported nausea and headaches, the control tower lost its radios, and Guinness still lists it as the loudest aircraft ever flown, though nobody ever measured it. This is the story: why the Navy and Air Force wanted a jet-fast propeller fighter, how Republic rebuilt an F-84F around a 5,850-horsepower Allison turboprop, why the airplane was built crooked on purpose, the twelve test flights and the eleven that ended in emergency landings, the pilot who flew it once and refused to fly it again, and where the only survivor stands today. Chapters 0:00 Towed out onto the dry lake 0:33 The Thunderscreech 1:46 Why build a plane like that 2:26 An F-84F rebuilt around a turboprop 3:22 Built crooked to fly straight 3:57 A propeller that never slowed down 5:09 Twelve flights, eleven emergencies 6:27 The propeller that fought itself 7:10 Cancelled 7:30 Two airplanes, one survivor 8:20 The Tu-95 8:39 Why it made its… 📎 SOURCES & CREDITS (used in this video) YouTube: • XF-84H flight, pilot Lin Hendrix, Edwards, 9 Oct 1956 (film F-0281) — sdasmarchives — https://www.youtube.com/watch?v=Ns5LJHeAd4g • The Republic F-84H Thunderstreak (Thunder Screech) — spottydog4477 — https://www.youtube.com/watch?v=UFhSzReWTgs • Republic XF-84H Thunderscreech (hangar, run-up, taxi, flight) — aviationvideosarchivespart3276 — https://www.youtube.com/watch?v=DrIu2YoDMPM • Republic XF-84H walk-around — thatwoodwardcruiser2056 — https://www.youtube.com/watch?v=DpANhnnbtrg • XF-84 experimental aircraft at the Air Force Museum — MilitaryHistoryandAviation — https://www.youtube.com/watch?v=s3sx2ObyGVI • XF-84H moving into the fourth hangar, NMUSAF — TheaterMDS — https://www.youtube.com/watch?v=8MOVnHW8jSo Wikimedia Commons: • Edward air base.jpg — Unknown author Unknown author (CC BY-SA 3.0), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:Edward_air_base.jpg • Edwards AFB satellite photo.jpg — Copied to wikipedia commons by Chillmann (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:Edwards_AFB_satellite_photo.jpg • Republic XF-84H USAF.jpg — USAF (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:Republic_XF-84H_USAF.jpg • yt_runup2_22p5.jpg — Wikimedia Commons, via Wikimedia Commons • Republic XF-84H (27441401454).jpg — Clemens Vasters from Viersen, Germany, Germany (CC BY 2.0), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:Republic_XF-84H_(27441401454).jpg • Republic XF-84H Thunderscreech U.S. Air Force Museum (66).jpg — Bubba73 (CC BY-SA 3.0), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:Republic_XF-84H_Thunderscreech_U.S._Air_Force_Museum_(66).jpg • Republic XF-84H Thunderscreech Republic XF-84H, 51-17060-FS-060 on display at Edwards Air Force Base, 1950's (16148472550).jpg — San Diego Air & Space Museum Archives (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:Republic_XF-84H_Thunderscreech_Republic_XF-84H,_51-17060-FS-060_on_display_at_Edwards_Air_Force_Base,_1950%27s_(16148472550).jpg • 303d Tactical Reconnaissance Squadron - Republic RF-84F-25-RE Thunderflash - 51-17007.jpg — United States Air Force (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:303d_Tactical_Reconnaissance_Squadron_-_Republic_RF-84F-25-RE_Thunderflash_-_51-17007.jpg • Allison T40 turboprop at USAF Museum.jpg — USAF (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:Allison_T40_turboprop_at_USAF_Museum.jpg • F-84F Thunderstreak.jpg — U.S. Air Force photo (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:F-84F_Thunderstreak.jpg • 20th Fighter Wing F-84 at RAF Wethersfield.jpg — USAF, The original uploader was Bwmoll3 at English Wikipedia .,5 August 2006 (original upload date) (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:20th_Fighter_Wing_F-84_at_RAF_Wethersfield.jpg • F-84F F-100D F-101B F-102A from ANG in flight c1970.JPEG — USAF (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:F-84F_F-100D_F-101B_F-102A_from_ANG_in_flight_c1970.JPEG • F-84F 162nd FS Ohio ANG in flight 1960s.jpg — USAF (Public domain), via Wikimedia Commons — https://commons.wikimedia.org/wiki/File:F-84F_162nd_FS_Ohio_ANG_in_flight_1960s.jpg • mus_walk2_39p0.jpg — Wikimedia Commons, via Wikimedia Commons • yt_sdasm_40p5.jpg — Wikimedia Commons, via Wikimedia Commons All footage, images and recordings belong to their respective owners and are used under their stated licenses or as fair-use commentary/education. Contact us for credit updates or removal.