This was a quick read but definitely an interesting read. I am not sure if the G-800 has done the same with 100% SAF but they have done some SAF flights recently.

https://www.ainonline.com/aviation-news ... ation-fuel
[quote="Aviation International News Online"
Gulfstream G650 Flies on 100% Sustainable Aviation Fuel
by Curt Epstein
- December 19, 2022, 11:43 AM

Gulfstream late last week became the first business jet manufacturer to fly one of its aircraft on 100 percent sustainable aviation fuel (SAF). Friday’s milestone demonstration flight........
<snip>
“At Gulfstream, leading our industry closer to decarbonization is a long-standing priority, and testing, evaluating, and promoting new developments in SAF takes us another step closer to that goal,” said company president Mark Burns. “We are grateful for our partnership with Rolls-Royce to be able to demonstrate yet another milestone in these efforts.”
[/quote]

If I understand it, biodiesel and SAF are using a lot of plant oils and even animal fats, with some sophisticated chemistry to make the overall package work as fuel.

I am kind of amazed that anything that starts from a plant or animal can still flow well at FL410 in the cold, and avoid decomposition sitting on a 100 degree ramp in the sunshine.

It is ironic that the key technology allowing 100% SAF rather than 50% is getting the natural rubber out of the seals and going “unsustainable” on the fuel system seals….

With the shortage of water and land to grow food for a growing population, using it for biofuel doesn't make sense. Oh, wait a minute, I forgot; we'll be eating insects.

Here's an article on SAF; calling the "boon" a "boondoggle."

https://airwaysmag.com/us-saf-goals-mired-in-myth/

That's the number 1 cause of climate change, population.

Everybody talks about other solutions, but nothing really matters if we don't control that. People avoid talking about it because it is not proper to suggest this solution.

If the planet had 1 billion people on it instead of 8 billion, there would be no climate change issue at all and we would all have effectively 8 times as many resources per person as we do now. Rain forests wouldn't be cut down, animals would have more space, we'd have plenty of energy, etc.

The planet has a sustainable capacity and we are probably well past it. An economic and political plan of constant growth WILL FAIL, it has to when there are finite resources.

Some family with 4 kids in an electric minivan and a solar powered house has a FAR higher carbon footprint than I do flying my old Citation around because their footprint includes the total sum of ALL the carbon their kids, and their grandkids, and the great grandkids, and so on, are going to emit.

The world says the USA emits too much carbon, but that is because they are measuring PER PERSON. What that does is artificially lower the carbon metric for overpopulated countries like China and India. If you instead measure it PER LAND AREA, then the USA is doing actually quite good and we have a fairly low carbon footprint. Measuring per land area is a FAR better metric since it favors countries who have lower populations, and that's the prime factor to capture. An even better metric would be total NET carbon produced by people versus what the land CAPTURES. In the USA, we have a lot of agriculture and natural vegetation that captures a lot of carbon. In contrast, Canada captures a lot less per area due to short growing season and being cold, so their carbon metric isn't as good as one might imagine due to the sparse population.

In other words, the carbon output of the USA is actually quite low, but this doesn't fit the current political "climate" so we don't hear about it in those terms.

Mike C.

"over population"

The Canadian prime minister might agree with you, as he introduced a new program for seniors, euthanizing them. For us, Planned Parenthood is working on the issue with abortions right up to the moment of birth, assisted with our tax dollars.

I don't believe at all that the earth is overpopulated. We've just picked all the low hanging fruit for sustainability, and haven't directed enough technology to the issue.

We have more inhabitable unpopulated land than populated land, and much of it lacking water for food production , forestation. Nuclear powered desalination plants and a pipeline infrastructure can turn arid land into lush gardens generating carbon offsetting oxygen. Carbon capture and putting it back into the earth is being developed.

That's the number 1 cause of climate change, population.

Everybody talks about other solutions, but nothing really matters if we don't control that. People avoid talking about it because it is not proper to suggest this solution.

That's the number 1 cause of climate change, population.

Everybody talks about other solutions, but nothing really matters if we don't control that. People avoid talking about it because it is not proper to suggest this solution.

If the planet had 1 billion people on it instead of 8 billion, there would be no climate change issue at all and we would all have effectively 8 times as many resources per person as we do now. Rain forests wouldn't be cut down, animals would have more space, we'd have plenty of energy, etc.

The planet has a sustainable capacity and we are probably well past it. An economic and political plan of constant growth WILL FAIL, it has to when there are finite resources.



Some family with 4 kids in an electric minivan and a solar powered house has a FAR higher carbon footprint than I do flying my old Citation around because their footprint includes the total sum of ALL the carbon their kids, and their grandkids, and the great grandkids, and so on, are going to emit.

The world says the USA emits too much carbon, but that is because they are measuring PER PERSON. What that does is artificially lower the carbon metric for overpopulated countries like China and India. If you instead measure it PER LAND AREA, then the USA is doing actually quite good and we have a fairly low carbon footprint. Measuring per land area is a FAR better metric since it favors countries who have lower populations, and that's the prime factor to capture. An even better metric would be total NET carbon produced by people versus what the land CAPTURES. In the USA, we have a lot of agriculture and natural vegetation that captures a lot of carbon. In contrast, Canada captures a lot less per area due to short growing season and being cold, so their carbon metric isn't as good as one might imagine due to the sparse population.

In other words, the carbon output of the USA is actually quite low, but this doesn't fit the current political "climate" so we don't hear about it in those terms.

Mike C.

If we have some glaciers that melt you get more water. Problem solved!

It is if everybody lives at your standard of living. There just aren't enough resources to have 8 billion people live like you on the planet.

We can keep most of the world poor and have this many people, or we can reduce population and let everyone live well.

That's pretty much the two possible outcomes.

The main driver of resource consumption isn't population growth right now, it is the elevation of standard of living of formerly poorer populations. There are now almost 300 million cars in China, for example. If all 8 billion people live like that, there are going to be issues.

Mike C.

One might think, but we have the same amount of water on Earth as we did when the atmosphere was created. It just changes phases, liquid, solid, gas. Us 60's hippies had it all wrong, "Save water, shower with a friend" but at least it worked out well for us guys when the friend was a female.

One might think, but we have the same amount of water on Earth as we did when the atmosphere was created. It just changes phases, liquid, solid, gas. Us 60's hippies had it all wrong, "Save water, shower with a friend" but at least it worked out well for us guys when the friend was a female.

Most sustainable fuels consume, water, sunshine black dirt, and in many cases, natural gas to create a liquid fuel.

Water and black dirt are far more precious resourses than a liquid fuel. And they are not replaceable in any short term schedule.

Much of the western US is going to face a water crisis before a real fuel crisis as populating increases.

The seals were switched between types of synthetic rubber. There is no mention of natural rubber. The writing clarity is however poor and seems to incorrectly imply that the original seal material was of natural origin.

“In the past, Rolls-Royce told AIN that in the company's modern powerplants, such as the BR725, traditional nitrile seals have been supplanted with those made from synthetic materials such as fluorocarbon and fluorosilicon that are unaffected by aromatic content, allowing them to safely use neat SAF.”