Jet A-1

[PA39]

What is the specific gravity of Jet A1 at the moment ?

[ravan]

Depends on what the temperature is "at the moment"......ERSA GEN-CON-2
says AVTUR SG = 0.8 if that is any help.

[Capt Fathom]

Depends on the local temperature, which in turn is governed by the season, and the fuel installation (above or below ground tanks).

Anywhere between 0.785 to 0.805, excluding extremes. So 0.795 would be a good average!

[Fred Gassit]

Local refueller can tell you daily generally, last time I checked: .782

[Grogmonster]

Fred

You are very correct and therein lies another question? Does JetA1 lose calorific value with SG. In other words does it supply less bang for your buck than fuel with an SG of 0.805 ?

Groggy

[Tmbstory]

In six years of flying in Japan, the Jet A1 specific gravity reading was supplied with the
fuel docket.

Tried to get that to happen in Australia and failed !!.

Tmb

[waren9]

My outfit uses .79 unless the refueller notes it differently. Seems to work well with the accuracy cross check.

[Bullethead]

In other words does it supply less bang for your buck than fuel with an SG of 0.805 ?


You get less bang for your buck per litre of warmer, i.e. lower SG, fuel and the same per kilo. Energy available is directly related to the mass of fuel not the volume.

Regards,
BH.

[Silverado]

Does JetA1 lose calorific value with SG

No

In other words does it supply less bang for your buck than fuel with an SG of 0.805 ?

If your buying in litres, yes

[jetstar1]

Only some of the places I go into have temp / density on the fuel dockets.

The last few I can see are:

21.8C / 0.793 kg/L
22.8C / 0.789 kg/L
25.6C / 0.789 kg/L

Cheers!

[Wally Mk2]

Specific gravity varies with batch from the refinery as well. The crude used varies so hence does the end product. Fuel arriving into a terminal via pip-line for Eg could have one batch S.G. where as the following batch (pumped up behind from another refinery, we are talking millions of ltrs here) could be quite different, the 'mix' had to settle & an overall S.G. would be taken & promulgated as the current S.G. on subsequent delivery dockets. Colour also varies from 'water white' to a 'straw colour' so if yr new to Jet fuel use caution as Jet-A1 can look pretty much like pure water!

Other uses:
Diesel engines although use an oil additive as Jet A1 is very 'dry' & will ruin injector pumps/nozzles after time
Oil burning heaters, the old 'kero' heater works very well as Jet A1 is far more highly refined than the 'rubbish' that consumers used for their old oil heaters. (you would be surprised at the rubbish/slops that went into the large storage tanks at the refineries that was eventually used for oil heaters.
Washing paint brushes etc although not very nice on the skin, use effective barrier cream.
A good trick to newbies entering the field of fuel depot activities was to take a sample of the jet fuel into a clear glass beaker then dip a finger into that sample whilst the newbie was watching with some level of anticipation then quickly (so as to not let the newbie see yr actions) slip a dry (unused) finger into yr mouth & say....'yep that's a good batch'!!!:}

Okay that's enough useless info:ok:

Wmk2

The range as stated here covers most batches supplied by the refineries.


Wmk2

[Brian Abraham]

The permissible SG range is quite wide. The specifications call for a SG of between .775 and .84 at 15°C.

Net heat of combustion (calorific value) has to be greater than 42.80 MJ/kg.