jet fuel

[jgf]

Spent an evening reading about jet fuel, it is basically kerosene.  Various formulations around the world use slightly different additives but nothing caustic or even specifically toxic.  In fact the only "different" jet fuel seemed to be formulations used in extremely cold areas.

 

Now growing up in a rural area, kerosene was common.  Used in stoves, furnaces, for cleaning machinery, even for cleaning us after an afternoon working on a car or truck (just pour it over your arms, scrub off the grease and oil, then wash off the kerosene with soap and water).

 

So, to the point.  I recently watched a documentary about a passenger jet crash in shallow water which said the survivors suffered more injuries from being "burned" by the jet fuel floating on the water than by the impact itself.  I don't understand.

[lnuss]

3 hours ago, jgf said:

"burned" by the jet fuel floating on the water than by the impact itself.  I don't understand.

Apparently the fuel tanks ruptured and the exiting fuel floated on the water (diesel, kerosene, gas are lighter than water) and the fuel apparently caught fire. So the injured must have been in or immediately adjacent to the water.

[jgf]

Yes, the fuel was floating on the water, but there was no fire (flight attendants were warning people not to light matches or lighters).    The water wasn't deep (it was a swamp) and photos showed rescuers wading around, knee deep to waist deep.  The implication was the fuel itself burned the skin.

 

This is the crash - https://en.wikipedia.org/wiki/Eastern_Air_Lines_Flight_401

 

note, "... received burns to his face, arms, and legs—a result of spilled jet fuel..."

and, "Fourteen survivors had various degrees of burns"

 

Neither this article nor the documentary mention any fire, in fact rescuers had trouble finding the crash site because of the dark night. 

[jgf]

addendum - the documentary notes one of the rescuers "immediately felt the sting of jet fuel on his legs"

 

(couldn't edit previous post)

[J. Nyhus]

9 minutes ago, jgf said:

Yes, the fuel was floating on the water, but there was no fire (flight attendants were warning people not to light matches or lighters).    The water wasn't deep (it was a swamp) and photos showed rescuers wading around, knee deep to waist deep.  The implication was the fuel itself burned the skin.

 

This is the crash - https://en.wikipedia.org/wiki/Eastern_Air_Lines_Flight_401

 

note, "... received burns to his face, arms, and legs—a result of spilled jet fuel..."

and, "Fourteen survivors had various degrees of burns"

 

Neither this article nor the documentary mention any fire, in fact rescuers had trouble finding the crash site because of the dark night. 

I seem to remember a show interviewing the guys who were on the airboat, who saw her go in, and they stated they saw an explosion in the air, then a second explosion, (assumed to be the impact), at which point they rushed to the area... Seeing flames around the area as they got closer, along with much more graphic experiences of what they saw. I could assume, maybe, they were dealing with highly heated floating fule that hadn't ignited. At the same time, people have different tolerances for what are considered irritants.

[PhrogPhlyer]

Jet A is an irritant in normal usage and simple skin washing would prevent any skin issues. However, in high concentrations any irritant could cause extensive skin damage. People stating the could "feel" the fuel in the air were most likely experiencing varying levels of irritation on any exposed skin, eyes and the respiratory tract. I've attached the Safety Data Sheet for Jet-A, and you will note it is listed as an irritant, but not a corrosive.

 

 

SDS Jet A.pdf

[J. Nyhus]

1 hour ago, PhrogPhlyer said:

Jet A is an irritant in normal usage and simple skin washing would prevent any skin issues. However, in high concentrations any irritant could cause extensive skin damage. People stating the could "feel" the fuel in the air were most likely experiencing varying levels of irritation on any exposed skin, eyes and the respiratory tract. I've attached the Safety Data Sheet for Jet-A, and you will note it is listed as an irritant, but not a corrosive.

 

 

SDS Jet A.pdf 284.61 kB · 0 downloads

I agree with you. At the same time, I've been around fuel vapers in quantities where you can "feel" it around you, (as in, a change in air density) and it can be very unpleasant, especially when your pores are open (sweating) and are under stress. Beggs the question... could that have been what they were recounting?

Given this happened in the 70s, I'm curious what the difference may be, compared to the 2021 SDS you linked... And out of left field, is there one for JP-7?

[PhrogPhlyer]

9 minutes ago, J. Nyhus said:

I'm curious what the difference may be

Jet fuel is fundamentally the same be it JP-5 or 7, Jet A or any other variant. The differences have mostly to do with additives for  freezing temperature and a variety of mission/aircraft specific requirements. As for health hazards, they are all basically the same. And yes, individual response to exposure can be different based on exertion, temperature and other variables.

[J. Nyhus]

4 minutes ago, PhrogPhlyer said:

Jet fuel is fundamentally the same be it JP-5 or 7, Jet A or any other variant. The differences have mostly to do with additives for  freezing temperature and a variety of mission/aircraft specific requirements. As for health hazards, they are all basically the same. And yes, individual response to exposure can be different based un exertion, temperature and other variables.

Fair points.

[jgf]

An "explosion in the air" is odd because there was nothing wrong with the airplane til the impact;  an explosion on impact is believable, though why did that not ignite all the spilled fuel that would have gushed out on impact.

 

As an aside, in reading about this I came across an interesting bit of trivia - some airports are converting all their diesel powered vehicles to run on jet fuel.  While diesel is cheaper it is in the long run more economical for the airport to maintain storage and pumps for one type of fuel rather than two.  The main issue is that diesel has lubricating qualities and jet fuel doesn't, so the pumps for the vehicles must mix a small amount of oil on delivery.

[Miggers]

Knew a guy that had worked at the old BAe Woodford(used to be Avro's) site,he reckoned everyone ran a diesel engined vehicle.

They used to get jets in for repair and modifications,the first thing they did was drain the fuel tanks,they had tons of the Jet A-1 in 40 gallon

oil drums.

They'd worked out the ratio of turbine oil to -A1 to make it as "oily" as diesel,he reckoned it burnt cleaner than diesel did and gave

slightly better miles per gallon to boot.

[PhrogPhlyer]

21 hours ago, jgf said:

why did that not ignite all the spilled fuel that would have gushed out on impact.

This has to do with the flash point of diesel (52 and 96 °C or 126 and 205 °F)) compared to the flash point of gasoline (-49°F or -45 °C). Even with an impact it is difficult for diesel (or Jet-A/JP) to ignite.

[jgf]

44 minutes ago, PhrogPhlyer said:

This has to do with the flash point of diesel (52 and 96 °C or 126 and 205 °F)) compared to the flash point of gasoline (-49°F or -45 °C). Even with an impact it is difficult for diesel (or Jet-A/JP) to ignite.

Just my point, an open flame (or explosion) would have ignited the fuel.  But the situation was just thousands of gallons of fuel floating on the water, and many survivors, and rescuers, were "burned" by mere contact with, essentially, kerosene.

 

Admittedly some people may have more sensitivity, but that large a portion of the passengers of one plane?  And to the degree of being "burned"?

[PhrogPhlyer]

48 minutes ago, jgf said:

And to the degree of being "burned"?

I think this is the real question also. I think that the reports stated "burns" (which many interpreted to mean heat burns), when they most likely should have said "chemical burns."