Is it really Prist

[pelmet]

I remember an F/O saving the day(and probably a lot more) once by sniffing what was in the water meth tank during the walkaround and discovering that it was jet fuel. Multiple aircraft had this done to them. Can you imagine an airline losing three aircraft in a day at various locations when they individually later on in the day needed to do a wet takeoff?

But I think it is reasonably safe to smell water methanol. As for Prist…..it is pretty nasty stuff. So how do you ensure that it really is Prist? Below is the reason I ask the question.....

"Situation:
There’s a worldwide fuel scare again - and we’re going to summarise this as simply as we can. Last week, a Falcon 900 departing an FBO in Florida requested Prist - which prevents fuel freezing at altitude - to be added. However, the Prist container on the fuel truck had been filled, in error, with a different fluid - Diesel Exhaust Fluid. The two fluids look the same - no coloring in either, clear liquid. DEF has catastrophic consequences for aircraft engines. In this case, 1 engine failed on departure, and the 2nd failed during the subsequent emergency landing. Similar events happened in Omaha in 2017, and we have more reports from OpsGroup members in Brazil. An FAA Special Airworthiness Bulletin is being worked on. There is no easy fix, but crews should be aware of the risk, and read more on this topic."

[digits_]

That's easy: don't design airplanes that need it. Nowadays there are multiple airplanes and engines that do not need it. I find it curious that a modernly designed airplane still needs it. In the long run it would probably be safer and cheaper to take a performance or weight penalty and design the planes just a wee bit differently.

[pelmet]

That's easy: don't design airplanes that need it. Nowadays there are multiple airplanes and engines that do not need it. I find it curious that a modernly designed airplane still needs it. In the long run it would probably be safer and cheaper to take a performance or weight penalty and design the planes just a wee bit differently.

Seems like a reasonable idea. But until then, unfortunately, we have to deal with what we've got.

Any suggestions?

[Taxivasion]

I don’t see this being an issue that should keep you awake at night.

Most turbine engines will burn almost anything that’s flammable including 100LL, heck even car gas if really in a pinch. I’m pretty sure DEF or something even remotely similar to Prist will be a non event.

How do you know DEF would be catastrophic?

Most modern airplanes don’t require Prist. I think it’s more of a habit with old dogs, at least in the corporate world.

[digits_]

How do you know DEF would be catastrophic

See initial post.
It caused a dual engine failure

[C-GGGQ]

Not sure about turbines but a trucks tank in bold print says "do not mix or blend DEF with fuel. Extreme engine damage" highly corrosive pig urine with mess everything up

[pelmet]

AOPA and other industry groups are stepping up efforts to prevent incidences of jet fuel being contaminated with diesel exhaust fluid (DEF)—likely mistaken for fuel-system ice inhibitor—following an August event in which clogged fuel filters led to the failure of two of a business jet’s three engines, and several occurrences last year.
The bizjet, a charter operator’s Dassault Falcon 900EX, made a forced return to Florida’s Miami-Opa Locka Executive Airport after the crew received multiple clogged fuel filter warnings on departure, followed by failure of the trijet's No. 2 engine, according to a letter from the air charter company, alerting AOPA and others. A second engine failed during the return to the airport and the crew successfully completed an emergency landing with the remaining, No. 1 engine. The event’s duration from initial alert to landing was about 10 minutes, it said.

The Aug. 14 incident raised new concerns following occurrences in November 2017 in which several airplanes received jet fuel to which DEF had inadvertently been added instead of fuel system icing inhibitor, often referred to by the brand name Prist, at Eppley Air Field Airport in Omaha, Nebraska. The addition of contaminated fuel, and the servicing of other aircraft with refueling equipment that had been exposed to the substance, prompted the FAA to issue a Special Airworthiness Information Bulletin on Dec. 26, 2017, urging operators of certain aircraft to familiarize themselves with maintenance and inspection methods; report related service difficulties; and avoid using fuel suspected of being contaminated. In response to the Omaha incidents, the National Air Transportation Association (NATA) released a DEF Contamination Prevention training course through its Safety 1st Supplemental Safety Training program—available free of charge to anyone in the industry.

According to the SAIB, “DEF is a urea-based chemical that is not approved for use in jet fuel. When mixed with jet fuel, DEF will react with certain jet fuel chemical components to form crystalline deposits in the fuel system. These deposits will flow through the aircraft fuel system and may accumulate on filters, fuel metering components, other fuel system components, or engine fuel nozzles. The deposits may also settle in the fuel tanks or other areas of the aircraft fuel system where they may potentially become dislodged over time and accumulate downstream in the fuel system as described above.” The SAIB identified aircraft that “have experienced clogged fuel filters and fuel nozzle deposits that led to service difficulties and unplanned diversions.”

“After this new incident, we feel a broader, collaborative approach is needed to help ensure another event doesn’t occur,” said David Oord, AOPA senior director of regulatory affairs. “Additionally, it is important for operators to be aware of the issue, and if a fuel filter light comes on, land as soon as practical and look for the possibility of DEF contamination. We are working with the FAA, NATA, National Business Aviation Association, and other stakeholders to provide additional education, awareness, and other measures to help prevent another DEF-contamination occurrence.”

[pelmet]

FAA SAIB...

https://www.nbaa.org/ops/safety/HQ-18-08R1.pdf

[Stallspin]

I would hazard a guess that .125% water/urea mix will not cause a flameout unless you fuel the night before and the DEF settles to the bottom of your tank where the pickup is.

I would bet that other aircraft have been fuelled with DEF instead of FSII but they departed quickly enough that the DEF didn't settle. If you took off right away you probably wouldn't have any idea.

[pelmet]

What pilots can do about this situation....

https://www.aopa.org/news-and-media/all ... dium=email


"The ASI Safety Notice urges pilots to inquire if fuel providers use DEF in ground equipment and about procedures to confirm that only the correct additives are used for jet fuel. Procedures should include separate storage, clear labeling, confirmation of correct additives at the time of insertion, and personnel training."



http://download.aopa.org/advocacy/2019/ ... 1557722522

[North Shore]

I’m struggling to comprehend how DEF got anywhere near an aircraft fuel source? Some major league fackery going on to get a vehicle exhaust additive confused with an aeroplane fuel additive, no?

[photofly]

It can't be beyond the wisdom of someone to create a simple to use test kit, like the ones they use for first line narcotics testing.
Here's a test for urea in milk; it should be straightforward to adapt for fuel.

Similarly, a test for prist could be developed...?

[oldtimer]

I have zero aquantenance with DEF except truckers say the DEF pumps will freeze in cold weather. But to answer why pilots will use Prist when aircraft usually do not require it is like a belt and suspenders thing. The manufacturer of Prist had to guarantee it would preform as advertised as an anti-ice additive but what I read was they also wanted to advertise/certify it would help clean jet fuel and the aircraft fuel systems by destroying Humbugs. (Hydrocarbon Utilizing Microbes, read the SA226 Merlin/Metro maintenance manual). In order to do that, the Prist manufacturer had to obtain certification from the USA Dept. of Agriculture. The cost was too much so they just said it should help "clean the fuel system", but with no guarantee. Careful and conscientious mechanics/pilots say the cost of adding Prist to the fuel is worth the small cost. What is certified is the use of Prist in the aircraft fuel systems because the components should be protected from the corrosive effects of Prist. At least that is what I have read.

[GoinVertical]

I've heard the same as above... that it's wise in aircraft that are sitting more than they are flying, as it stops gunk from growing in the fuel tanks, which is a very expensive problem to have.

Do any tri-hole Falcons require Prist?

[Heliian]

The use of FSii is still recommended in some aircraft for cold weather.

At some point you have to hold the fuelers accountable for the product they deliver. I wouldn't even bother to worry about if they put the correct stuff in the tank, the quantity is the most important.

[valleyboy]

a Falcon 900 departing an FBO in Florida requested Prist

Likely a pilot watabe driving the tanker

Let's face it most people today have no mechanical knowledge they have no clue the difference between adding DEF fluid or Prist to the truck all they know is that there is a jug and you poor it in -- Like most things in aviation, from refueling to driving a MAX training and the lack there of always rears it's ugly head.

[Cessna driver]

I hate when people call it prist…

[linecrew]

I hate when people call it prist…

Agreed. Prist is just one company that makes fsii, among other products as well.

Where I worked, the stuff came in clearly marked barrels and you filled the small additive tank on the truck with it. Then it was automatically blended into the fuel if the aircraft if the pilot requested it.

[Brantford Beech Boy]

Do any tri-hole Falcons require Prist?

The Dassault AFM for the 50 & 900 list approved anti-icing additives and their maximum concentrations ....otherwise provides no guidance for its use.

But I was told in groundschool that fuel anti-icing is not necessary due to design of the fuel delivery system.
Have never considered anti-icing “Prist” as a biocide... purpose designed biocides are better if the plane will sit for long periods, but bio material is best kept out by leaving the tanks pressurized.

We never request “Prist” and haven’t had any issues..

This was a discussion topic in recurrent this year.

BBB

[Heliian]

Pryst couldn't substantiate the claims of anti microbial or anti fungal use.

Biobor is really the only one that does antimicrobial.