Aircraft Accidents and HAZ

Did you ever watch an Arnold Schwarzenegger movie?  I swear airliners, trucks, cars, motorcycles, unicycles, skate boards, Big Wheels, roller skates … they all explode with such ferocity all from a fender-bender type impact.  I would find it believable if all the bad guys were driving Ford Pintos (I guess you younger folks will have to look that up), but they’re not.  My favorite is Bruce Willis’s character, John McClane, opening that engine valve on the B747’s #2 motor … you know, that secret valve that starts dumping fuel like Niagara Falls, so he can ignite it with a common lighter and explode the airliner on take-off.  I can’t tell you how many accident investigations I was on where THAT’s happened.

No, seriously, I really can’t … um, tell you.

It’s Hollywood; the brighter, louder, more fantastic the explosion, the more aviation people scratch their heads going, “Did he just open a valve on the … where did he find that valve?”  We recognize that movie makers are going for the Wow! Factor; it’s understandable.  After all, Hollywood is having such a hard time with believability these days.

Talking about things that go ‘PHOOM!’ in the flight, last week the Federal Aviation Administration (FAA) proposed a fine of $50,000 dollars (yes, that’s four zeroes) against a shipping company in France for violating United States (US) Federal Hazardous Materials (HAZ) Transport regulations.  The fine was set for shipping six plastic bottles of liquid disinfectant spray (think the French version of, e.g. Lysol) on two American Airlines flights from Blagnac, France through Dallas, Texas, then onto Nuevo Leon, Mexico.  The bottles were not labeled properly as hazardous materials, which they are.

Meanwhile, in Charlotte, NC, a shipping company violated US hazardous laws by shipping 142 lithium batteries in checked baggage; they are also being fined fifty thousand dollars for not notifying American Airlines of the batteries on two flights connecting Charlotte to San Francisco, via Dallas.  All-in-all, a busy week for American Airlines’ Dallas Operation.

Lithium batteries – charged or uncharged – are prohibited from being shipped as air cargo on US passenger airliners; only uninstalled spare batteries are allowed in check-in baggage; even so, there is a limit.  Lithium batteries are suspected to have been involved in the UPS flight 1307 inflight fire in Philadelphia, PA; the FedEx flight 1406 in Newburgh, NY; and the UPS flight 0006 fatal inflight fire in Dubai.  There is a legitimate safety concern with shipping lithium batteries in large quantity, especially in a cargo hold that has flammable bags, clothing and boxes that are inaccessible to the flight crew, as in ValuJet flight 592.  Luggage that is loose in the belly of a narrow body aircraft is a problem; having the luggage containerized in a wide-body airliner is more difficult to extinguish.

Where the French shipper erred was that they violated the International Civil Aviation Organization’s (ICAO) rules for transporting HAZ – Annex 18: The Safe Transportation of Dangerous Goods by Air – and ICAO’s Article One: The Contracting States Recognize that Every State has Complete and Exclusive Sovereignty Over the Airspace Above Its Territory.  Article One covers flights into, out of and over each member state, e.g. the US, France and Mexico.  These rules are different for each state; some are stricter than others.  ICAO, originally comprised of the Allied Nations of World War II in the 1944 Chicago Convention, before expanding to include 191 separate states, determines international agreements in relation to aviation.

But let’s be clear: HAZ is not to be taken lightly.  For instance, certain HAZ materials can become an aerosol on contact with atmosphere; if drawn into the air conditioning system they can blind or cause dizziness to the pilots … you know, those men and women flying the airliner.

How are Hazardous Materials classified?

  1. Class 1 – Explosives
  • These are divided into projectile, mass explosion capabilities or fire hazard.
  1. Class 2 – Gases
  • Divided into flammable, non-flammable and toxic gases
  1. Class 3 – Flammable Liquids
  2. Class 4 – Flammable Solids
  3. Class 5 – Oxidizing Substances
  • Divided into oxidizing substances and organic peroxides
  1. Class 6 – Toxic and Infectious Substances
  • Divided into toxic and infectious substances
  1. Class 7 – Radioactive Materials
  2. Class 8 – Corrosives
  3. Class 9 – Miscellaneous Dangerous Goods

In a cargo aircraft, HAZ is isolated and controlled.  While some can be loaded with other freight, e.g. magnetic materials, they still have to be kept a safe distance from aircraft wiring and electronics.  Other Restricted Materials, aka ORMs, e.g. dry ice, must be limited in quantity; they go directly from a solid to a gas; they give off ‘smoke’ as a byproduct.

How the HAZ is isolated is by containerizing it.  Unit Load Devices, aka Containers, designed to carry HAZ are completely metal, including the door.  This is because metals, e.g. aluminum, have a higher burn rate than plastic or collapsible Containers.  The metal doors form a better seal that keeps oxygen out and the smoke in.  The HAZ Containers often have a corrugated floor, not so much for strength, but to channel HAZ liquids away from other HAZ freight.

The bigger the aircraft, the broader the options for shipping HAZ.  A narrow body aircraft might contain a single position (or station) of HAZ, while a wide-body cargo jet can have up to three different HAZ Containers, all located behind the cockpit.  Each HAZ Container has netting to separate the HAZ freight from each other, since certain HAZ cannot be located next to, below or on top of other HAZ freight, e.g. Corrosives and Flammable Liquids.  If there’s a spill, the corrugated floor prevents the corrosive fluids from a leaking drum on one side of the HAZ Container, from coming in contact with a flammable liquid drum on the other side of the HAZ Container – it could happen.

The HAZ is separated, restrained and enclosed inside the HAZ Container.  There is one more safety measure to protect the crew and aircraft: the extinguisher system.  Quite simple, yet effective, each HAZ Container is assigned its own fire bottle/extinguisher.  Restrained against a bulkhead or the aircraft’s side wall, the fire extinguisher(s) connect to their own hose, which is routed into the separated cargo cabin; the pilot doesn’t go near the HAZ Container.  With one end of the hose attached to the bottle, the other end is attached to the HAZ Container by a quick-release adapter, located dead center, above the access door.  In case of fire, the pilot breaks the safety on the bottle and shoots the extinguishing agent directly into the HAZ Container.

The reason cargo airlines ship HAZ freight is simple: money; lots and lots of money.  If done right and according to the rules, shipping HAZ freight is as harmless as shipping a suitcase full of cotton pajamas.  Perhaps I shouldn’t use that analogy: I hear Hollywood is filming a remake of the Doris Day classic: The Pajama Game, starring Arnold Schwarzenegger; and I’ll bet cotton pajamas will be bursting into flames all over the screen.

“Que Sera, Sera … Baby.”

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