Black Thursday': The bleakest day for U.S. Army Air Forces in World War II > Air University (AU) > Air University News
![Pop Mech Defense on X: "Rusty nail and ball bearing pipe bomb, one of many cool weapons in a prop supplier arsenal: http://t.co/59PF0ZmNmU http://t.co/VMkZixs1X4" / X Pop Mech Defense on X: "Rusty nail and ball bearing pipe bomb, one of many cool weapons in a prop supplier arsenal: http://t.co/59PF0ZmNmU http://t.co/VMkZixs1X4" / X](https://pbs.twimg.com/media/BmE0NLZCQAAjkDB.jpg)
Pop Mech Defense on X: "Rusty nail and ball bearing pipe bomb, one of many cool weapons in a prop supplier arsenal: http://t.co/59PF0ZmNmU http://t.co/VMkZixs1X4" / X
![Boston bombing 2013: Devices were packed with ball bearings to inflict the most injury | Daily Mail Online Boston bombing 2013: Devices were packed with ball bearings to inflict the most injury | Daily Mail Online](https://i.dailymail.co.uk/i/pix/2013/04/17/article-2310236-19550215000005DC-891_634x342.jpg)
Boston bombing 2013: Devices were packed with ball bearings to inflict the most injury | Daily Mail Online
![The devastatingly simple mechanics of the #Boston marathon bomb – an annotated graphic – Engineering & Technology magazine The devastatingly simple mechanics of the #Boston marathon bomb – an annotated graphic – Engineering & Technology magazine](https://engtechmag.files.wordpress.com/2013/04/boston-bomb-attack.jpg)
The devastatingly simple mechanics of the #Boston marathon bomb – an annotated graphic – Engineering & Technology magazine
![Behaviour of a blast-driven ball bearing embedded in rear detonated cylindrical explosive - ScienceDirect Behaviour of a blast-driven ball bearing embedded in rear detonated cylindrical explosive - ScienceDirect](https://ars.els-cdn.com/content/image/1-s2.0-S0734743X20307685-gr6.jpg)
Behaviour of a blast-driven ball bearing embedded in rear detonated cylindrical explosive - ScienceDirect
![steel ball Steel ball bomb, 8mm 9mm 10mm 10mm /600-7mm/200 Bearing balls (Size : 9mm/200) : Buy Online at Best Price in KSA - Souq is now Amazon.sa: Everything Else steel ball Steel ball bomb, 8mm 9mm 10mm 10mm /600-7mm/200 Bearing balls (Size : 9mm/200) : Buy Online at Best Price in KSA - Souq is now Amazon.sa: Everything Else](https://m.media-amazon.com/images/I/61nSjmxws8L._AC_UF1000,1000_QL80_.jpg)
steel ball Steel ball bomb, 8mm 9mm 10mm 10mm /600-7mm/200 Bearing balls (Size : 9mm/200) : Buy Online at Best Price in KSA - Souq is now Amazon.sa: Everything Else
![Photograph from a B-17 Flying Fortress of 8th U.S. Army Air Force Bomber Command during a bombing run on the CAM ball-bearing plant and nearby Hispano Suiza aircraft engine repair depot in Photograph from a B-17 Flying Fortress of 8th U.S. Army Air Force Bomber Command during a bombing run on the CAM ball-bearing plant and nearby Hispano Suiza aircraft engine repair depot in](https://external-preview.redd.it/photograph-from-a-b-17-flying-fortress-of-8th-u-s-army-air-v0-VOP8ktMp5wDVdFlERNo_Bup7cvpP0xy5Vv2USioXspM.jpg?auto=webp&s=3a2701270a41156f9203e3701d23a98a22ea0f24)
Photograph from a B-17 Flying Fortress of 8th U.S. Army Air Force Bomber Command during a bombing run on the CAM ball-bearing plant and nearby Hispano Suiza aircraft engine repair depot in
![What is shrapnel? Bomb fragments that cause terrible injuries and can include nails, metal shards and ball bearings | The Sun What is shrapnel? Bomb fragments that cause terrible injuries and can include nails, metal shards and ball bearings | The Sun](https://www.thesun.co.uk/wp-content/uploads/2017/05/nintchdbpict000326052380-e1495525248633.jpg?strip=all&w=627)
What is shrapnel? Bomb fragments that cause terrible injuries and can include nails, metal shards and ball bearings | The Sun
![Liverpool ball-bearing terrorist bomb could have caused 'significant injuries', say police - The Mail Liverpool ball-bearing terrorist bomb could have caused 'significant injuries', say police - The Mail](https://media.glide.mailplus.co.uk/prod/images/950_633/gm-3a73fc2e-b97a-401e-897d-a7200dab79dc-liverpool2.jpg)