With the developing fuel crisis (for want of a less dramatic word) occurring in the UK and Europe*, some changes are occurring which might affect you (if you fly into the UK or Europe).

*Yes, I know the UK is in Europe, just not the EU, but Europe comes under EASA and the UK comes under the UK CAA.

What’s the problem?

With the ongoing conflict in the Middle East, the Strait of Hormuz is closed. Blockaded to be precise. The Strait used to handle around 20 million barrels of refined oil a day. Or 20% of the global fuel consumption if you prefer percentages.

Europe received around 60%-75% of their jet fuel imports from this region, and are still struggling to find replacement suppliers. The result is a lot of flight cancellations across Europe (due to rising costs*, not lack of availability), and some airports having to dip into reserves to prevent shortages.

*European jet fuel jumped up to almost double initially, although has reduced a bit since.

How the UK are handling it

The UK are relaxing sanctions on Russian oil. That doesn’t mean shipping in oil from Russia, but they are allowing imports from India and potentially Türkiye, both of which refine Russian crude oil.

The UK is also allowing airlines to cancel flights into EGLL/Heathrow and EGKK/Gatwick. In the past, this has not been possible – to retain slots (which are expensive to buy and tricky to keep hold of), airlines have had to utilise them a minimum of 80% meaning they sometimes flew empty or ‘not well filled’ aircraft just to avoid losing these.

The change will allow airlines to cut flights at least 2 weeks in advance – enabling passengers a little more chance of finding alternative travel, and helping airlines deal with the fuel price, and potential shortage, situation which is still fairly dynamic.

How EASA are handling it

EASA (and the UK probably too, they just haven’t announced it yet) are going to bring in USA produced jet fuel to fill up the holes in their tanks. Only problem is, the fuel types aren’t entirely the same.

The USA produces Jet A fuel, while Europe uses JET A1 (so does Australian, Africa, India, South East Asia, most of the Middle East etc).

So what’s the difference?

Well there is actually very little difference between the two in terms of quality and refinement. Jet A filled airplanes run just as well as Jet A1 filled airplanes. You can even mix it up and have a bit of both if you want to.

The BIG difference, and the one that has led to the need for a Safety Information Bulletin (SIB)* however is the fact Jet A freezes at just -40 degrees C while Jet A1 freezes at -47 degrees C. That’s 104 degrees Fahrenheit and 116/ degrees Fahrenheit if you work in them.

Basically, it’s a bit of a problem if you’re flying somewhere very cold and forget about it because when fuel starts to freeze it gets all thick and gloopy and fuel lines get blocked and engines shut down and it’s all very upsetting.

*The SIB actually covers all the differences and concerns for other teams too. There are some in there for fuel handlers, storers, aerodrome operators etc. I’m just talking for pilots here.

For pilots, you need to remember this:

• Jet A1 freezes at -47°C
• Jet A freezes at -40°C

Let’s look at the SIB

The worry is folk might not be aware of what they are getting. When you fly to the USA, you know you’re filling up with Jet A. When you fly out of Europe you know it’s Jet A1.

Easy to remember, and easy to apply the correct temperature limitations.

Now though, you might get Jet A at one European airport, and not at another. Jet A1 here, Jet A there, you might even get a bit of both, especially if you’ve tankered from somewhere else.

All of which makes knowing which temperature to apply a little tricky.

So what the SIB therefore talks about, in summary is the importance of knowing what is going into your tanks.

I posted it above, and here’s the link again in case you need it to read it: https://ad.easa.europa.eu/ad/2026-04

How will you know what you’ve got?

• Check NOTAMs: The fuel availability at the airport should be advised in these, especially if it is different to the usual
• Confirm with the fuelling agent: Confirm with the handling or fuelling agent so you can think about it in the planning stage
• Check the fuel receipts: Always check these for a final confirmation of what has been loaded onboard

Plan for it:

• Apply the right temperatures: Know which freezing point applies and brief in advance. If you are carrying a bit of both, apply the most restrictive.
• Check the cruise altitude temperatures: This will depend on your aircraft type and how well those wings keep the fuel warm. A good rule of thumb for when you should start really be monitoring on ULR flights is around the -65°C mark, especially if you’ll be in those temperatures for extended periods.
• Consider replanning: If you will be flying in low temperatures for prolonged periods, considering replanning a lower level to avoid issues.

In-flight actions:

• Monitor! Keep an eye on the fuel temperatures.
• Brief: Know what to look out for which indicate early signs of cold fuel problems
• Know your aircraft: Some aircraft are better are maintaining fuel temperatures than others. Some have more limiting restrictions (mine is -42°C plus 3 degrees above the freezing point of the fuel for when I need to start worrying!)
• If it’s getting cold: Descend to a lower level, or consider speeding up to help increase the temperature:
  • Descending 7000’ leads to approximately 7°C increase in TAT (but 7000’ lower burns a lot more fuel so you might want to have thought about this in the planning stage)
  • Speeding up M0.01 will give you around a 0.7°C increase in TAT.
  • Mix it up: Some aircraft have cold fuel checklists which provide actions to take, and may involve turning pumps and crossfeeds and what have you on to help mix the fuel with other fuel from warmer tanks (the outer tanks tend to get cold quickest).

Remember BA…

British Airways Flight 38 crashed just short of Heathrow’s runway back in 2008 after they got ice crystals in their fuel lines.

They had been cruising in OATs reported to be between -65°C to -74°C. The fuel didn’t freeze entirely but the ice crystals did partially reduce the fuel flow leading to reduced thrust when they really needed it – at low level on the approach.

Fuel for thought

Be aware! The End.