Explained: Jet A vs Avgas Aviation Fuels

DALLAS — When it comes to aviation, different aircraft require different fuels based on their engine type. Here’s a breakdown of the key differences between these two standard aviation fuels, starting with engine Types and fuel compatibility.

Aircraft with turbine engines, such as jets and turboprops, use Jet A fuel, which is kerosene-based and colorless. There are two main types, Jet A and Jet A, with slight manufacturing differences, but both are interchangeable. 

Conversely, piston-engine aircraft, like those used for flying clubs or agricultural purposes, require Avgas (aviation gasoline). The primary Avgas grades are Avgas 100 (green) and Avgas 100LL (blue), which have low lead content.

Performance Differences

Jet A fuel is highly refined, ensuring stable performance across varying conditions, especially in high-pressure environments. Its lower auto-ignition temperature helps reduce pressure in aircraft engines. 

On the other hand, Avgas contains tetraethyl lead to boost octane levels and enhance engine performance, particularly in valve assemblies. Avgas 100, with its 100-octane rating, resists spontaneous combustion under compression, ensuring smooth operation.

Theres also the issue regarding weather resilience. According to monmouthjetcenter.com, weather plays a critical role in fuel performance. Jet A has a freezing point of -40°C (-40°F), while Jet A1 performs better in colder climates with a freezing point of -47°C (-52.6°F), making it ideal for long international flights. 

Though not commonly used in extreme cold, Avgas 100LL freezes at -58°C (-72°F). While rare, water in the fuel system could freeze and block fuel lines.

Cost Considerations

Aviation fuel prices are influenced by global market factors. Jet A fuel is generally easier to obtain, and its pricing can be monitored via the International Air Transport Association (IATA) Jet Fuel Price Monitor. 

On the other hand, Avgas's price varies depending on local supply logistics. Based on available data, we can compare the current jet fuel prices to the same period last year.

According to IATA’s fuel monitor, the global average jet fuel price is US$92.76 per barrel as Q1 2024. This translates to approximately US$2.21 per gallon (assuming 42 gallons per barrel). In the US, jet fuel cost US$88.3 per barrel during the same period, or about $2.10 per gallon. 

We can make some comparisons based on the available data:

1. In January 2023, U.S. airlines' fuel cost per gallon was US$3.28. The current price of around us$2.10-US$2.21 per gallon represents a significant decrease from early 2023.
2. In June 2023, jet fuel was US$2.25 per gallon. The current price is slightly lower than this mid-2023 figure.
3. Current prices are substantially lower than in early 2022 when they peaked at over US$4 per gallon due to the Ukraine war.
4. As of September 6, 2024, the weekly average was US$88.47, -4.6% lower that the previous week.

Factors Influencing Prices

The jet fuel market has seen considerable volatility over the past couple of years due to various factors:

• Recovery from pandemic-related demand drops
• The impact of the Ukraine war on global oil markets
• Changes in refining capacity and logistics constraints

While prices have generally trended downward from the peaks seen in 2022, they remain higher than pre-pandemic levels. The current prices reflect a stabilization compared to the extreme volatility experienced in the previous two years.