We are only at the beginning...

@@AgentJayZ It will be interesting to see how these new advanced blades go and what other low hanging fruit they find worth investigating on the engine. As you said in the last video, even a 1% improvement is a very big deal. If a blade does let go, I hope the team still share the findings and are not deterred.

Turbo: Stage one blades are surrounded by, and eat, inlet air. The air they move gets its first bit of compression when it passes through the stage one stators right behind these blades. The only time they might get warm is when they encounter the heated air exhausting from the IGVs when the anti ice system is on. Usually, the anti ice system is not present on industrial engines. A bit of a special case, as all downstream stages work on progressively higher temperature air.

@@AgentJayZ It seems that the comment oversimplified the aspect of “hot vs cold” as hot terminology in this case is more about “physical deformation” due to loading more than temperature (which is my interpretation of the wording). This reminds me of the time that a saw a test article at a national laboratory of an aerodynamic control surface that was machined into the “distorted configuration” out of a stiffer material for testing in a supersonic wind tunnel. The person that was my “family guide” explained what it was from. The aerodynamic control surface “fin” was amazingly distorted as exhibited in its “static but actually dynamic form”. Presumably the composite compressor blade will “deform & twist” differently than the metal one if both are of the same geometry and thus changing the angle of attack and performance. Also, how are the test going to validate the vibrational characteristics of the composite to metal interface at the root? If wear, damping and fatigue life could be issues, are not coatings (and compatibility with lubricants if used) have to be validated (lots of test)? Also, could not airfoil erosion be an issues with the softer composite materials (don’t some composite fan blades have leading edge metal protection)? This seems like an interesting project, hope backers are liberal with stock options.

Rejected. Anybody who wants to use words like hot and cold, but have special meanings to those words MUST supply their special definitions. If not, hot means hot, and cold means cold. Jeez. Get the hell outta here. If you didn't know I hate Jargon, then you know it now. Also, I'm just the photographer, as explained before, and in the video.

Geez, I wish all of my first tries and proof of concepts went as well as this demonstration did. Good job Jay. You may have the only photography record of a test like this in the entire world. I'm glad you were there and that you were able to share it. Thank those people for that. In this context let's substitute "at rest" for cold and "at work." for hot and not even think about it anymore.

Thanks, joncarroll8662, but I stand by my vehement reee-jection of substituting any word meanings without notice. That is jargon, and jargon is garbage. "Oh, well... you're just supposed to know that". Get stuffed.

wonder if they can embed? overmold? not sure the correct term here..some metal in that area if wear becomes as issue.

@@Live.Vibe.Lasers I wonder how the same issue is dealt with on the composite fan blades, or to say it a different way, how are those type of fan blades mounted to the hub?

G'day JZ, Fascinating, Very very fascinating. I was wondering about the Compressor version of the "Fir-Trees" holding the Blades to the Hub... I also wondered why you didn't run 4 Test Blades in two Pairs which would have been 180° apart from each other - eliminating the need to add Fudge-Weights to compensate for the Out-Of-Balance Radial Asymmetry (?). Were those two Suits Naturalised Canadians, Canadians born to naturalised Migrants, Or is the DemoKratic Republick of Kanadia selling itself And renting the Test Facilities out to Unkle Spam's Designated NEXT Enemy (AnyMe?) Of CHOICE....; The better to build Shiny Bright New and Super LIGHT, Carbon Fandangled Fibre-forged Helical Compressor-Blades for the Glorious, Long to reign victorious, PLAAF Sky-Fightery Hairygoplanes, all currently a' buildin' and amassing, and all lined-up, Ready and waitin' to go out and Repossess and Liberate the (long lost, misguided) Island Province of Formosa...? Here in Oz, In our SuperMax Dungeon in Goulburn, wasting away in Solitary Confinement..., Our Spooks are holding an Ex-Yanqui USMC Harrier-Pilot, who renounced his AmeriKan CitiZenship to become a Rubber-Stamp imprinted "Naturalised (Faux) Ozzie" and tried to make a living flying for himself as a Civilian in Tasmania. After that (predictably) failed, he opened an Advanced Jet-Combat Manouvreing Flight-Training School, in Sooth Effrika... Teaching Chinese "Airline Pilot Cadets" EVERYTHING which Unkle Spam had taught him about how the Yanqui Air Forces have Bin-Practicin' to Defeat the expected Swarms of PLAAF Warplanes When China repossesses Formosa. To cope with the numbers of Students he was pumping through, the cunning little BarSteward Hired an actual mob of miserably recently retired Unemployed discontented and disgruntled British Ex Fighter-Pilots, As his Air-Combat Instructors. All drawn from the legions of Passed-over Time-expired Time-servers, who were summarily Retired - rather than being further promoted, and whose Personnel Record for being trouble-prone had made them clearly unfit for Airline Employment..... The British closed their Legal Loophole, and prosecuted the Brit's who worked for him, and the CIA ordered ASIO to arrest Mister Duggan, Hold him in Solitary Confinement in our SuperMax, and our Courts Ordered him to be Deported back to face the Muzak in the 'MurriKa he Betrayed for Money.... Are you being Well paid to test Radical Revolutionary Lightweight Experimental Chinese Jet Engine Technology ? How are the other 4 Nations' of the celebrated, "5-Eyes Intelligence Community"..., Have to say about what you're all being Proudly Paid to Achieve...? (The "5-Eyes" being Oz, Canadia, Britain, AmeriKa & Kiwiland - English-Squeakers all !). You appear to me To be Sailing perilously close to the Track taken by Bruce Wilson of xjet Channel... The Kiwi who secured a Contract to supply 5,000 cheap Pulsejets to the US Navy, for Target Drones..., and then when the Iranian Government asked to buy some... The silly fool asked his governing Kiwis in Auckland - and they greenlit him to agree to the idea. And when the US Congress heard of that, they SuckCessFully pressured Kiwiland's Tax Department to foreclose on Wilson's old Income Tax Debts, requiring instant settlement rather than payment via installments.... Wilson couldn't raise that money, so he went bankrupt ; and the US Dep't of Defence Contract had a Clause dissolving the agreement if EITHER Party was to go Bankrupt. So the lucrative US Contract evaporated, and he was Bankrupt, and with no Factory to build Pulsejets...; the Iranians were sorry to have bothered him - and the US Navy still shoots down expensive TurboFan-powered Drones for practice, rather than loud cheap Pulsejets from Kiwiland... I suspect that you may be cruising For a bruising, on this particular track. It was all looking good, to me, Until those two tall Chinamen in Suits walked into the Frame... Are you tracking down the same ambitious little road which totally Buggared Bruce's Busyness-Plan, and also put Mister Duggan right where Julian Estrange likes to Fantasize that he may himself be going... (To die in Prison in the USA) ??? Unless their Height betrays a lifetime of being raised in the West - & fed on KFC & Macca's, in Kanadia or the Excited Status of Norte-ArmedmeriKano...(?) ! One worries about you, JZ...; You're so very Target-Fixated on the Technicalities of the Engineering...; that I wonder if you pay sufficient attention to where the Money is coming from..., and to - as Machiavelli put it..., "To determine whom is responsible, whenever anything Unusual occurs...; first Look to see Whomsoever Benefits the most, Therefrom..." Depending on who's actually Funding, & Using..., All this Research, then you-all might yet get to be Lionised..., Or Demonised...(?). All dependant on whom your Paymaster turns out to be, Actuarially...(!). Thyme will tell, I guess. Such is life, Have a good one... Stay safe. ;-p Ciao!

It would probably benefit the developers to employ some engineers and material scientists with forged carbon fiber experience and ask for their recommendations

@@johncarroll8662 They probably do. They would not have gotten to where they are now without some competency. What they probably could use is some technical people that have experience in instrumenting and collecting the relevant data on the dynamic behavior of these blades. MAN has a great youtube video on determining the dynamic motion of compressor blades under test (during surge testing). This is probably a different skill set than an aerodynamicist or a material science specialist. Besides the younger “SUIT” had a reaction that would suggest … Just reviewed the pertinent video where they show “aspects” of the “tip timing system” on their “Blades Asynchronous Vibrations” testing system. They don’t explain very much but a “picture” is worth a thousand words if you have a little background. Funny thing, the video has only had around 20 views in nearly 10 years (and I have watched it a number of times).

Just what I was thinking, took the words out of my mouth.

I have fond memories of riding the “Zillertal Bahn” and others many years ago. I wish that I was there getting the cinders in my eyes while sticking my head out the window watching the beautiful scenery.

The bare weight of the LM1500 is about 1750kg. The weight of a single stage 1 blade is (from memory) about 2kg, and the carbon one is about 0.5kg (I'm sure Agent JZ will correct me if I'm too far out). So if all 1st stage blades were replaced that's about a 30kg reduction. But that's only the first stage, and there are about 17 stages - however I doubt that more than the first couple of stages could be replaced due to the temperatures in the latter stages. The engine has a lot of mass that is NOT in the compressor, but is in core, the frame and the power turbine - and these bits aren't being replaced as part of this project. BUT reducing the dynamic mass of the first couple of stages would have a larger effect than doing the same for the final stages, and this might give an improved output power, or a reduced fuel consumption - both desirable depending on the application of the engine.

Doing the math it sounds like 9lbs in first stage.

I guess weight of the engine is not the most important factor here, these are industrial stationary engines beeing used on the ground. But! AFAIK the weight saving for the blades could factor in performance of the engine, but as far as I understood/guessed the difference is in the profile of the blades itself (and I'll stand corrected here at the first hint of me beeing wrong).

All of the stages where the temp is within the capabilities of the material might weigh about 50 lbs. The LM1500 is a little over a ton, and the main rotor is about half of that.

@@darknase What are you even talking about?

No center shaft. The bearing is just sitting on the table. Piece of rubber sheet on top. I put the hub on there by hand and got it close. Meh.

How many 100’s of millions of dollars do you want to spend on this ‽ Besides, don’t you think that the jet engine designers at the big name companies have just overlooked this concept ‽ Probably grahamj9101 would have some insight into these topics.

Rolls Royce has made composite turbofans for years, normally limited to the leading bypass fan blades in commercial engines. Slightly more interesting but separate from jet engines, Bell Helicopter uses composite rotor blades and have for over a decade. I've been through their massive composite plant and watched the process, quite fascinating on its own merit.

@@C-M-E yup but these are in new engines that were designed from the go to use these components, not and upgrade to legacy designs from the 50s.

@@C-M-E No, R-R are still using their SPF/DB (superplastically formed/diffusion bonded) titanium hollow fan blade technology for the current range of Trent engines. R-R's Ultrafan technology demonstrator engine has some pretty blue composite blades, with titanium inserts at the leading edges. GE have had a composite fan blades in their GE90s for years now.

Hopefully we will never get that data. We've seen many a destroyed compressor when a piece of metal goes in. We usually replace the entire rotor, and all of the stators.

The normal LM1500 test nozzle, which is non-variable and sized to be at what would be called military if it was on a J79. A straight pipe would be far less noisy, because the exhaust would not be moving as fast.

I doubt that the airworthiness authorities would allow them anywhere near a J79, no matter how much ground running they had done. Just imagine how it would be branded as a "scandal" if there was ever a failure because something that was originally designed for use on the ground was actually allowed to fly.

@@grahamj9101 General Electric GE 90 & GE nx airliner Fan Jet engines, both have fan blades made out of carbon fiber and the containment shroud is also a carbon composite material. I would think under a test program Approved and co authored by GE and the company making these NEW "Forged first stage carbon compressor blades, presented to the FAA would get test approval . The operators of the GE J 79 with Afterburner sure could use this new technology to reduce fuel burn in the GE J79, of course with afterburner use never mind. yet at super cruze, with a lighter J 79, would help in profit margins of operators of older jets with the GE J 79. One user "Starfighters Space" might want this and would probably get engineering help from GE and Lockheed. Just my thoughts.

When the rack we mount the engine stands to was upgraded, the result was the engine centerline was about 2 ft (60cm) lower. This happened about ten years ago.

Very good question. I don't have the answer.

@@AgentJayZ I feel like a child before Christmas I am researching and making plans One video showed a very weak electric motor Upgrade ! change switch to variable resistor What a project I cannot wait This PT 6 A 680 hp replica powered Draco wilga I became instantly impressed with its ability Have a good evening my friend, warm I hope so 👍

That many of the early axial flow jet engines started without any form of airflow control (VSVs and/or bleed valves) is a fact - but then some didn't and wouldn't. Axial flow compressor design was far from an exact science: It could be got more or less right at the design point, but there could be unknowns at part speed. For example, there could be a nasty 'kink' in the working line, which intersected the surge line at part speed (or vice-versa) And, of course, here in the test cell, the engine is running behind a near-optimum bellmouth intake. Put it behind the tortuous bifurcated intake of an F-104, or an intake with ramps, etc, of an F-4, then actual intake conditions could be very different. If I had been involved in the design of that machine and its VSVs (but I'm not old enough to have been!), I would have aimed to have a significant margin, so that the engine wasn't teetering on the cliff-edge of a surge, even if the VSV mechanism was malscheduled to some degree.

And then, of course, there's the issue of handling and throttle response. It's one thing to open (or close) the throttle carefully and avoid a surge in the test cell. But what about when a pilot opens up at the end of the runway to military and goes into reheat/afterburner? He needs a rapid response and adequate surge margin, even when the engine is well off-design and the VSVs are closed. After an overhaul, I would expect the engine normally to have a pass-off test with the VSVs scheduled in accordance with the manual. Equally, i would hope that if it was tested (inadvertently or otherwise) with a degree of malscheduling, that it would still start. if not, then it might not have adequate surge margin to operate out there in the "Oh ****!" real world of a military engine. And I would expect the industrial gas generator to behave similarly.

@@grahamj9101 it is nice to hear from somebody who knows what he's talking about and you are from the UK as you didn't say AB AgentJayZ says he works on mainly old turbojet engines but references other engines frequently like the B737 5th and 9th stage bleed air Engine problem with a similar part & the An-124 Turbo fan problem Avid AJZ fan also he's great I love this subject

Engines that are still being used, but have parts which are no longer available, could benefit from this technology.

That was idle, and she was not directly in front of the engine. It's true that it was not really necessary to disconnect the starter hose, so we stopped doing that.

@@AgentJayZ Do you think that the engine cover would handle a blade structural failure? I've seen an A380 engine explosion test but what about the J79 cover? Is it tested for structural integrity in the unlikely possibility of a blade failure?

The compressor case is designed to contain a steel blade failure. It would have no problem with containing one of these.

Maybe in the next video. You know the old saying: serious inquiries only.

@@AgentJayZ Oh im serious! I design and manufacture forged composites for a living. They are a bonded sub-assebly in our prepreg carbon products

As these seem to be developed for stationary engines, I'd guess there's better protection from moisture (rain, snow, etc) then an aviation engine. So likely less concern about galvanic aspects.

Please explain this type of corrosion with regard to carbon fiber & epoxy? Is this that different compared to a composite fan blade?

Like every LM1500, we put a jet nozzle at the end, and measure pressure rise ahead of it.

This is a special setup, created by us building the system with full manual control of the Variable Geometry system. Engines are never run this way except in experiments like this.

The rotor was balanced to normal standards.

@@AgentJayZ MAN Energy Solutions has some fascinating youtube videos on their testing of the AR-MAX1 compressor. Particularly interesting was how they could do realtime measurements of the dynamic vibrational behavior of the compressor blades (during surge testing). Seems like it is important to know the dynamics of the blade’s behavior and how it is vibrating in the hub’s slot where it could wear (but some vibrational damping occurs for the metal blades).

They should consider incorporating some carbon fiber or other inherently vibration damping material into the design, then reduce the mass as much as practical to limit the potential for vibrational energy buildup in the structure.

The rotor needs to be balanced to less than 1 gram-inch. Balancing the assembly assures that. Your second sentence I do not understand.

No, a lighter rotor would not be needed. The first-stage disc might be unnecessarily heavy for the lighter blades, but that's of no consequence. If this was a proposed design improvement for an in-service military engine, then the cost/timescale of including a redesign of the disc for weight reduction just might be considered.

It's designed to start in any combination of environmental conditions at or above sea level. You need to read about axial compressor design, what compressor stall is, and the various types of anti-stall technology before saying anything. I have videos on all those subjects. Then you will realize that your comment does not really have a meaning.

This is video from the first two days of what I expect to be a long, careful development program. Didn't I mention that? Yes, eventually these will be tested for months of full power running.

All of these submarine comments are irrelevant. Just go away.

Was also noticing the suits. Not seen any of them out at the test cell in videos I've watched so far.