F-35 Cancelled, then what ?

[George K Lee]

Bingo, Brat.

Next question - how, otherwise, are the Chinese plans for the deployment and development of LO technology different from the F-35 program?

Hint: H-6K, J-10B/C, J-20 roles and missions.

[Brat]

Play somewhere else Mr Lee.

[Turbine D]

Thanks for the article Brat.

There isn't enough rhenium in the world to supply the needs of GE, CFMI, RR & P-W let alone the Chinese entering the market. Rhenium is a by-product of copper mining where the copper ore contains molybdenum, not all copper mines contain rhenium. For the ones that do, rhenium content in the copper ore is measured in parts per million, 15-30ppm is typical as I recall. If copper demand sinks, prices go down and some mines close because mining costs are higher than copper prices. It is a tough element to be dependent on for turbine airfoils, both from availability and cost viewpoints.

[George K Lee]

So do many engine manufacturers use something else?

It's a new story to me, but high-temperature turbine production has been accelerating steadily for decades, and you'd have thought it would have been a flagged issue.

In any event, engine production for the J-20's not going to drive the exotic-metals market any time soon.

BTW, this was the only reference I could find:

https://www.washingtonpost.com/news/...=.930a6aed0857

[George K Lee]

As to the linked media release above about the program meeting its delivery goals....

Actually it seems they sort of did and sort of didn't, according to the highly professional Israeli site Defense Update.

In contrast to these positive news, the Pentagon’s contract management agency said the number of aircraft delivered in 2017 came short of its annual goal, because the 66 delivered included nine planes that were supposed to be delivered in 2016.

http://defense-update.com/20171218_f35_2017.html

Not the end of the world, but jeez, after 21 years of investment...

[A_Van]

Regarding raw metals in aviation in general, the following article might be of interest:


How Long Can the U.S. Rely on Russian Titanium? | RealClearWorld

[Turbine D]

Originally Posted by George K Lee
So do many engine manufacturers use something else?

It's a new story to me, but high-temperature turbine production has been accelerating steadily for decades, and you'd have thought it would have been a flagged issue.

It is true, rhenium has been used to add both temperature capability and improve high temperature strength in turbine airfoils for decades. But as events would have it, the availability of rhenium was an issue and worrisome but always available and manageable.

First it was used in petroleum cracking towers, those used to produce unleaded gasoline. It replaced 10% of the platinum catalyst at one tenth the cost of the platinum it replaced. That usage didn't affect the aircraft engine turbine market in the long run as the petroleum folks found a way to clean and reuse the rhenium after it ran through a cracking tower's catalyst total life cycle.

P&W were the first to use a substantial amount of rhenium in their proprietary high temperature alloys for turbine blades. However, that amount dropped off as their commercial engine business went down when GE's commercial business increased. GE entered the rhenium usage marketplace with the F110 engine competing against P&W's F100 engine. Then after settling a patent dispute with P&W, GE began to use it in commercial engines as well. The availability of rhenium remained acceptable because the price of copper rose and copper production increased as well as the supply of rhenium which mainly comes from a molybdenum producer in Chile but some from the US producer as well. Both GE and P&W maintained reserves in case the copper market changed. A typical high temperature superalloy contains 3% rhenium.

Then Rolls Royce entered the rhenium market on their newer commercial and military engine alloys. Everything was okay in the beginning because the Chinese were buying copper and molybdenum in huge quantities enhancing the availability of rhenium. Then a problem occurred, the Chinese copper and molybdenum market slowed and it became apparent there may not be enough rhenium available for all the new turbine airfoil production, excluding Russia from the picture. So what is the solution?

Develop new superalloys that have the same capability as rhenium containing alloys which do not contain rhenium or have a reduced rhenium content. I know of one engine producer that has done this with some success. Also, reclamation programs have been established with engine customers to reclaim used parts and recover the rhenium through remelting the recovered parts back into alloy for new rhenium alloy part manufacturing.

There is a lot at play when the material is a byproduct of a byproduct as is the case with rhenium.

[glad rag]

An interesting read, Turbine D: who is going to blink first in the resources race?

[ORAC]

The point about rare earths is that they aren’t rare at all, they exist everywhere, just at very low concentrations. rhenium is in minerals found everywhere, just at concentrations of about 1 part per billion. The reason copper and molybdenum ores are used as a source is because they possess it in higher proportions, and the cost is reduced as it is byproduct.

Yes, the price will go up; yes, as the price goes up alternatives will be found; but it won’t run out, and in a cost product like a jet engine, there will always be a source.

[Turbine D]

ORAC,

rhenium is in minerals found everywhere, just at concentrations of about 1 part per billion.

Rhenium rarely occurs as a native element or as its own sulfide mineral; most rhenium is present as a substitute for molybdenum in molybdenite. We have molybdenum mines in the US that do not contain rhenium, same is true of some copper mines. Sediment-hosted strata-bound copper deposits in Kazakhstan (of the sandstone type) that contain rhenium also contain harmful impurities that must be eliminated before using the resulting rhenium in superalloys at added costs.

https://pubs.er.usgs.gov/publication/pp1802P

[ORAC]

It is also found elsewhere, such as in manganese and uranium ores. As I said it is much lower concentrations and not currently economic to recover. But it is there if required, as the Russians researched.

http://www.sibran.ru/upload/iblock/3...f98515b5cc.pdf

[glad rag]

I'm sure there is a point on the periodic table where the elements become extra-terrestrial, think it's iron...

[ORAC]

Everything beyond hydrogen and helium. We are all the residue of nova and supernova.

[iranu]

It's off topic, but:

Availability of Rhenium will not be an issue when ceramic matrix composite (CMC) turbine blades become the norm.

I was involved with research into ceramic materials for static engine components in the early 90s. Specifically Silicon Nitride in the form of SiAlON as well as Silicon Carbide.

Neither of which were viable with the technology of the time, even for static parts, but lots of original work lead to a greater understanding of material properties and advancements in manufacturing.

CMCs are beginning to worm their way into commercial and military engines (see LEAP, GE9X and of course F135 exhaust nozzle). Those applications are all static components, but it's only a matter of time. I'd say about 20 years considering the development cycle.

[ORAC]

Lies, damn lies and.... No, unfortunately - just lies.....

[George K Lee]

It's hard to see what point they're even trying to make.

It's not a KPP, it doesn't appear to be funded for flight-test, few if any other fighters even bother to demonstrate with those Christmas-tree loads any more, you're not going to reach the WBY very fast with 27 klb thrust and > 70 klb gross weight and a 35-foot span, and you're not going far if you use burner all the way to altitude.

[FODPlod]

Not sure why some people are getting so upset about a graphic portraying potential developments.

[George K Lee]

Not sure why some people are getting so upset about a graphic portraying potential developments.

Exactly! It might be different if the program had a two-decade history of inflated claims and optimistic predictions, but we all know that's not the case.

[FODPlod]

Originally Posted by George K Lee

Not sure why some people are getting so upset about a graphic portraying potential developments.

Exactly! It might be different if the program had a two-decade history of inflated claims and optimistic predictions, but we all know that's not the case.

Could be worse:

1983 - Aircraft* development begins.
1994 - Aircraft first flight.
2007 - RAF takes delivery of first aircraft.
2017 - Aircraft achieves integration of MBDA Meteor Beyond Visual Range air-to-air missile.

* Eurofighter Typhoon. Other expensive jet fighters with protracted development programmes are available.

[George K Lee]

Very true, but missing an item or so:

1983 - Aircraft* development begins.
1989-92 - NATO's adversary self-destructs.
1990 - Germany elects government committed to cancel program.
1992-2000 - Partner air forces shrink, also slowing the increase in average airplane age.
1994 - Aircraft first flight.
1997 - German Government talked off the ledge.
1998 - Contract signed for production, and development of production-standard airplane.
2004-20XX - One government or another (usually Germany) drags feet over every stage of the contract.
2007 - RAF takes delivery of first aircraft.
2017 - Aircraft achieves integration of MBDA Meteor Beyond Visual Range air-to-air missile.

This blatantly erroneous tu quoque comparison has been part of the fans' manual since 2010 or so.

Rafale has a parallel story, but in that case the program had to accommodate the different needs of the AdlA, which was left well supplied with newish M2000s at the end of the CW, and the Aeronavale, which urgently needed an F-8 replacement.