From: bill.sloman@ieee.org   
      
   On 22/12/2025 6:27 am, Jeff Layman wrote:   
   > On 21/12/2025 17:33, Bill Sloman wrote:   
   >> On 22/12/2025 2:40 am, Jeff Layman wrote:   
   >>> On 21/12/2025 05:08, Bill Sloman wrote:   
   >>>   
   >>>> This is roughly equivalent to insisting that petrol-engined car won't   
   >>>> catch fire if you shoot a bullet into the petrol tank.   
   >>>   
   >>> It won't catch fire. You can search for this yourself:   
   >>>   
   >>> bullet gasoline tank fire   
   >>>   
   >>> It's a myth, mainly as a result of many Hollywood movies showing cars   
   >>> exploding from a single bullet to the tank. Even multiple bullets fired   
   >>> into a tank won't cause the fuel to ignite. You need an incendiary   
   >>> bullet, and even then you might require more than one.   
   >>   
   >> It's a bit more complicated than that. A half-full gas tank contains a   
   >> potentially flamable mixture of hydrocarbon vapour and air. There is   
   >> gear that extracts 99% pure nitrogen from air which you can use to   
   >> lightly pressurize the tank. Modern aircraft use it.   
   >>   
   >> Operations research on WW2 bomber losses took a while to work that this   
   >> was a useful trick.   
   >>   
   >> A single bullet may not always ignite a gas tank, but it happened often   
   >> enough over Germany in WW2 to take down quite a few bombers.   
   >   
   > They would have been brought down by cannon shells (20mm shells   
   > containing a small high-explosive charge), not bullets, which were   
   > highly inefficient:   
   >   
   > (from   
   > ):   
   >   
   > "Even if the eight Brownings worked perfectly, pilots soon discovered   
   > that they were not sufficient to destroy larger aircraft. Combat reports   
   > showed that an average of 4,500 rounds were needed to shoot down an   
   > enemy aircraft.[107] The main cause of this was the way the guns were   
   > mounted in the wing, allowing a dispersion of 1.1 metres at only 100   
   > metres range. Perfectly aimed fire just missed the target because of   
   > this.  In November 1938, tests against armoured and unarmoured targets   
   > had already indicated that the introduction of a weapon with a calibre   
   > of at least 20 mm was urgently needed"   
   >   
   > ME 109s were fitted with 20mm cannon, and in late 1943 the variant Bf   
   > 109G was fitted with 30mm cannon.   
   > ()   
      
   Cannon shells were lot more effective, but modern civilian airliners   
   have been lost to combustion in half-empty gas tanks, which is why they   
   are now pressurised with 99% nitrogen, not air. An incendiary bullet is   
   a much more reliable fire starter than a fast moving lump of lead, but   
   anything that can strike a spark can do the job.   
      
   --   
   Bill Sloman, Sydney   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)