Friday 18 June 2021


Projectiles are in the air! [har har]

Massive fail news on Bloomsday involved a case of a spectator getting concussed by a sliced golf ball . . . and suing the golfer, the club [no, not the 4-iron club; rather the "19th hole" club], and the organizers of the tournament. WTF? here's a grown-arsed man, a golfer even, who got dressed, left the house, put himself in the line of fire and then wasn't looking or paying attention when something happened on the golf course. Golf. like baseball and cricket, is only intermittently active, so you'd think you'd be awake when the ball was struck. The Judge in the High Court, quite properly IMO, ruled that Mr Campbell from Donegal was responsible for his own safety. Mr Campbell's lawyers will appeal because they are embedded in Ireland's compo culture.

Baseball crowd heroes is a regular youtube trope. Although I guess there's a grimmer parallel universe if you google "MLB tonk paramedic" [don't go there]

For aircraft bird-strike is an occupational hazard. Like golf, airports have a lot of green space between the fairway / runway: grass needs earth; earth hosts worms; birds eat worms so keeping birds out of the flight-path is important. Many airports take a leaf out of the Duke of Wellington's quip-book. When The Great Exhibition was opened in Paxton's giant glasshouse in 1851, Queen Victoria noted the presence of a great many sparrows [shitting] inside the building. Seeking a solution from her entourage, The Duke suggested "Sparrowhawks, Ma'am". But even with the best prophylaxis in place birds gonna strike and aircraft manufacturers need to engineer their planes to survive such an assault. It's a minimax problem: you don't need to worry about wrens Troglodytes troglodytes [10g]; but an Andean Condor Vultur gryphus [12,000g] strike is so rare that you can discount them also.

Boeing and Co have for a long time been using chicken as their preferred projectile and employ a flight impact simulator or "chicken gun" to fire at vulnerable parts [pilot windscreen and engine intakes] of commercial aeroplanes. They also worry about fatigue cracks around port-holes but birds will just glance off the sides of aeroplane fuselages. What everyone is concerned about is an uncontained disintegration [bloboprev] of the engine where bits fly out of, or through, the engine cowling and start peppering the fuselage, or the hydraulics of the rudder.

Chicken guns typically use compressed air as propellant and can deliver standard-sized chickens to target at up to 600km/h. Anything that breaks has to be sent back to the engineering drawing board. Now you may have noticed that a chicken is only approximately a cylinder. TIL [today I learned] that the chickens are usually inserted into a properly cylindrical cardboard "sabot" to make a snugged fit for the gun-barrel. Sabot is the French for clog. The old joke is about some noobs using a chicken-gun for the first time and causing consequential damage to their kit. An enquiry to the suppliers elicited the laconic reply "first defrost chicken". Snopes assures us that this is a joke rather than a True Story

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