Stupid questions and smart answers about jet fuel (JP-4, 5, 8, etc)

[Brunes]

Another question. What's the difference between JP-5, -8 -7, etc and Jet-A. I know on XCs you can't always find military grade jet fuel, but it can't be too different than Jet-A, right?

I think the real difference between -5 and -8 is the flash point more than the FSII...cause we used JP-5 w/FSII for helo refuels on my cutter.

JP-5 flashes off @ 60C and -8 flashes off @ 38C. They are both similar to Jet-A with some different additives then Jet A.

 

[Gatordev]

These days, it's JP-5 ashore

Friendly Fuel Truck at Oceana on Wednesday (before the rains came)



HJ Photo

All depends on where you're at. At K-Bay, it was -8 at home and you had to request -5 (if you knew you were going to the boat). Even then it wasn't really necessary since you'd burn the -8 off by the time you got to the boat. Makes sense a place like Oceana just has JP-5, since everyone could go to the boat at anytime.

Whiting was JP-8, at least for NSE, all the time. It's a rare occasion that a Wiener goes to the boat.

 

[HooverPilot]

Here is some info from the C-2 NATOPS. It shows the Jet A & B equivilencies... i.e. Jet B=JP-5, Jet-A=JP-4, Jet-A1=JP-8

 

[Gatordev]

Here is some info from the C-2 NATOPS. It shows the Jet A & B equivilencies... i.e. Jet B=JP-5, Jet-A=JP-4, Jet-A1=JP-8

But it doesn't say any of that. You are very sneaky...

 

[Brunes]

But it doesn't say any of that. You are very sneaky...

Yeah it does- Second image- Right hand side "Remarks" column.

 

[Pags]

I was under the same impression that Brunes with w/regards to flashpoint...JP-5's flashpoint is higher, that's why it's the shipboard fuel. I've heard that JP-8 is a better fuel, but we compromise with JP-5 for fire concerns aboard ship.

If you're flying to the ship to stay with anything other than JP-5 you're supposed to advise the ship so they don't hangar you.

The 60S can apparently work with JET B/JP-4, but good things don't happen, like flameouts.

 

[Gatordev]

Yeah it does- Second image- Right hand side "Remarks" column.

But the first one doesn't, which was why I said it (jokingly). That chart confuses me (I know, not hard to do). I don't ever remember hearing JP-4 called "Jet A." The -60B NATOPS itemizes it differently and has the JP fuels as "Primary" and then the "Jet A/Jet A-1" listed as secondaries (w/ Jet B/JP-4 listed as a no-no like Pags mentioned). The T-34 Natops barely makes an effort to tell you about fuel.

I'm not saying the chart is wrong, it's just a different notation than I remember ever seeing.

 

[Alpha_Echo_606]

A couple guys at work were talking about JP4, 5, 8, and AV gas at work the other day. One of the tin benders thought the P3s used AV gas. You'd think an A&P mechanic would know better. I ended up setting them straight.

 

[HooverPilot]

But the first one doesn't, which was why I said it (jokingly). That chart confuses me (I know, not hard to do). I don't ever remember hearing JP-4 called "Jet A." The -60B NATOPS itemizes it differently and has the JP fuels as "Primary" and then the "Jet A/Jet A-1" listed as secondaries (w/ Jet B/JP-4 listed as a no-no like Pags mentioned). The T-34 Natops barely makes an effort to tell you about fuel.

I'm not saying the chart is wrong, it's just a different notation than I remember ever seeing.

Yeah, that first chart can be confusing. JP-5/8/4 are the primary fuels for the COD and the secondaries listed are the civilian equivilents. We do end up using alternate fuels in the COD just because of the random backwoods places we end up on deployment.