A Blisk? A Blacer?

[@Millwright1Prepper]

Howdy Agent Jay Z, I work at the GE Industrial power overhaul plant in Houston Texas. LM2500/ 6000 and LMS 100. We love your channel keep up the great work. You’re a Wealth of knowledge.

[@AgentJayZ]

I'll trade you for a hat. What you want?

[@Millwright1Prepper]

@@AgentJayZ In 2020 the facility changed from GE to Aero Alliance. Still remains the Certified GE overhaul location. Name change when aero separated from GE oil & gas and GE aviation. I’ll see if I can find a Aero A. hat. Do you have an email?

[@AgentJayZ]

Check the channel page, eh?

[@sdkfz250b]

Here in Rolls-Royce we linear friction weld blades to a hub to create the larger Trent LCE blisks and similarly those used in F35 JSF. The weld spill around the blade foot is then profile machined away. The smaller blisks like the HP stage 6 on the EJ200 for example is machined from a solid disk using a 7 axis machine centre. The main reason for using blisks is weight savings.

[@lisandroantoniorodriguez9242]

O_O I knew compressor drums were friction welded for decades and heard they are now using linear friction welding. How does it work, how is the machine?Is it something ultrasonic or can you see it working with the naked eye?

[@majjuss]

it's clearly a bladed ring - Bling!

[@AgentJayZ]

Yeah, I realized that after shooting!

[@obsoleteprofessor2034]

The wind howls like the banshee.

[@travisk5589]

Is it the wind? It sounds weird and almost sounds like a bad echo. Edit; He just said it was the wind. And the space music.

[@SuperAWaC]

I have machined a few blisks. They are always fun to program. Lots of 5 axis motion that people always like to see.

[@tolikechicken]

After the 40th hour in cutting they can get a little boring ;)

[@SuperAWaC]

@@tolikechicken I go do other things rather than sit there watching ;)

[@krzysztofbroda5376]

damn this music with wind sounds gives a really nice aura. Reminds me of one flash game where you were a ninja penguin that had the same background music and noise

[@pinkdispatcher]

As to large engines using blisks: The Trent XWB and the Trent 1000 TEN use blisks in the first three stages of their HP compressors, made by Rolls-Royce Deutschland in Oberursel.

[@sdkfz250b]

We developed the method at our Annesley facility then read it across to Oberursel.

[@Tom-ll7xu]

Some of the largest blisks are on the Trent XWB-97. IPC stages 1 and 2 are both blisks. Very impressive to see.

[@grahamj9101]

The answer to your question: the terms 'blisk' and 'bling' have been around in the industry, not just for years, but for decades now. Those were certainly the terms we used colloquially, but what the official title was on the component definition and other documentation, I really can't remember now: put it down to age and infirmity. You discussed the advantages of a blisk: another advantage I don't think you mentioned is that it's lighter than the equivalent bladed disc assembly. And yes, larger engines do have blisks, and have done so for years. The three-stage fan of the EJ200 (it's F404 size), which was designed in the late 1980s, has all three stages as blisks. The five-stage HP compressor also has blisks, but my memory fails me as to whether it's every stage: the first stage might have separate blades. I believe that the later marks of Trent also have blisks in their HP compressors. The last I knew before I baled out through the escape hatch into retirement was that friction bonding of the blades on to the discs for the EJ200 fan was under development. This was, as I recall, initially for the individual replacement of damaged blades. However, the intention was for it to become the production process for blisk manufacture, to eliminate the need for expensively and laboriously milling the aerofoils out of the rim of a big disc blank.

[@beachboardfan9544]

Why does the use of blisks eliminate the need for IGV's on the EJ200? kzbin.info/www/bejne/r6aypWttaMp_rNE

[@grahamj9101]

@@beachboardfan9544 The use of blisks has nothing to do with the EJ200 fan not having IGV's: that's entirely down to the aerodynamic design. The clip doesn't actually claim that the blisked fan permits the elimination of IGVs, but I do acknowledge that it could be misconstrued as implying it. In the initial design stages of the engine, both the fan and the HP compressor had conventional dovetail blade roots. At R-R Bristol, we designed two fans for rig testing, one of which subsequently went into a ground use only development engine, the XG-40: neither of those fans had IGVs. The LP compressor of the Olympus 593 in Concorde did not have IGVs, nor did the HP compressor. The fan of the Pegasus in the Harrier does not have IGVs, nor does the LP compressor of the Industrial Spey that AgentJayZ has shown us,, which is derived from the Allison TF41. IGVs are not necessarily essential for either a fan or a compressor.

[@beachboardfan9544]

@@grahamj9101 What aerodynamic aspects determine the need for IGV's? I guess I'm really asking, if its possible to not have them why have them at all?

[@grahamj9101]

@@beachboardfan9544 Good question, but you really need to ask a compressor aerodynamicist, not this ageing, long-retired, mechanical designer.

[@grahamj9101]

@@beachboardfan9544 PS: The need for IGVs is determined by the the aerodynamic principles adopted by the aerodynamicist, and I suspect there's an element of 'design style' and preference involved: however, that's the suspicion of a mechanical designer. Going back into history, I vaguely recall coming across a story about Whittle experimenting with so-called inlet swirl vanes, which were really IGVs, for his early centrifugal compressors. I must trawl through my books to see if I can find some authoritative information. However, I do have the page of Hooker's book open in front of me, which tells the story of the inlet swirl vanes in the Nene engine, back at the end of WWII. Whittle had apparently demonstrated by then that they gave an advantage in terms of performance and/or surge margin in his engine. Nevertheless, there was a debate as to the need for them at R-R, and the Nene was designed with spacers at entry to the compressor, so that vanes could be easily retrofitted. On its very first test run, the engine gave 4,000lb thrust, but with a higher than predicted combustion temperature. The test was stopped and the swirl vane assembly fitted overnight. The next day the engine achieved its design target of 5,000lb thrust, with the same combustion temperature as the day before, and with a reduction in fuel consumption. I am also aware that, when I was an apprentice at R-R IMD, a maverick young development engineer decided, without approval from his seniors, to remove the LP compressor IGVs from a development standard Industrial Olympus. There was a measurable improvement in the engine's performance. It was the talk of the whole of engineering at IMD - but he got an official rocket for doing so. The engine still has its IGVs, as you will see in several of AgentJayZ's videos.

[@grahamj9101]

We discussed the layout of the Allison 250 in the previous clip, but there's nothing new under the sun about having a single combustor at the rear of the engine. Frank Whittle did it in 1938, with his second experimental engine. The compressor delivery air passed rearwards through ten curved diffuser pipes to the combustor (the PW100 did the much same, decades later). The flow from the combustor then passed forwards to the turbine, the exhaust from which was turned through 180deg, to pass rearwards through ten individual jet pipes. Now that certainly is reverse flow! And, after all these years, I've had a light bulb moment as to the reason why Whittle used those characteristic reverse-flow combustors in his W.1 and W.2 engines, which increased their overall diameter, relative to a 'straight-through' centrifugal engine. His very first experimental engine was never intended to represent the layout of a flight standard, and it had a single combustor, which was set to one side of the turbomachinery. Without the need for combustion chambers between the compressor and turbine, only compressor delivery and turbine inlet volutes, he kept the engine rotor short and mounted on two bearings. Having established this 'architecture' and running the project on very little money, he used the same rotor assembly through successive builds, right through to the third model of his experimental engine, which did establish the basic layout of his flight standard engines. However, with no way to place the combustors in the space between the compressor and turbine, they had to go around the turbine and jet pipe, with that reverse flow arrangement.

[@processserver8470]

Greetings from Greenwich London ⚓️⛵️👍

[@sgtjonmcc]

The wind is howling!

[@notyou6950]

The new GE blisk is a double disk the size of the fan you got standing against that wall. It takes weeks to machine. Expensive? Yes!

[@HerkCC]

I believe GE coined the term Blisk....Pratt refers to it as an IBR ( Integrated bladed rotor).

[@Kiera_Jackson74]

Resonance is something I've always fascinated with from an engineering point. I had an outboard that resonated with the hull at mid high rpm just by chance but it almost shook itself off the transom.... had to replace it with another motor I didn't really ask many questions it just didn't work with the boat inexpectly

[@brucematthews6417]

When discussing the cost of the blisk being held at around 15:00 to 15:30 sure, it's expensive. But can you imagine the total cost if it were made from separate disc and blades with micro dovetails? I'll bet the disk itself would be nearly the same cost as the blisk you're holding and on top of that the blades would add up to more than the cost of that blisk itself.

[@abarratt8869]

It's likely cheaper to manufacture and deliver, but more expensive in service. Of course, I'm presuming that only one part of a blisk gets damaged in service (requiring the change of the whole part) whereas a single damaged blade can be replaced if they're fir-treed. I I think there's also a weight saving; a mechanical joint like a fir tree weighs more than the equivalent strength single piece of metal. And weight is money.

[@SeanBZA]

@@abarratt8869 If you are going to strip down to replace a blade likely the whole section is going to go for a refurbishment operation anyway, to get the assembly balanced again. Much easier to have a single unit that you replace and send the old one off to the refurbishment shop, where they can do the precision work to either feather out the chip and rebalance, or just scrap it and give a new one. Price wise the labour cost for the operations will negate the advantage of having lots of interchangeable units, as your inspection time become exponentially larger and higher cost. Single unit, pull out, check the rest, put new, and put back together is a lot faster, and you can have a central shop that does the xray and refurb, as opposed to a hundred shops all running vastly under capacity. Of course both options you do need a fair amount of store inventory in the pipeline for both, but for single units part numbers are less, and you do not have to track a whole load of individually serialled items that are a matched set. One big box, as opposed to 200 little ones and a few bigger ones for the core.

[@Mishkx]

There is something about those Blisks/Blacers, they are very attractive to look at, i mean they are just mesmerizing, they are good for rechecking if you are being or not being a gearhead.

[@maineiacnorth1243]

The choice back ground music made it sound like a wicked Blisk was going on outside... Or was it a Blacer?

[@barnsley1066]

Most intresting and impressive engineering. 50,000RPM+, these things are awesome

[@ericdixon2898]

The first stage fan on the Honda Jet is a blisk. It's a medium bypass engine. I think the blades are friction welded on. The three stages of the low pressure section of the f-35 engine is also friction welded blisks with the first stage being hollow blades.

[@tolikechicken]

No! The HF120 is a blisk for the fan and the two axial stages cut straight from a titanium billet. I managed the entire manufacturing process for the fan and all 3 stages.

[@jamesshepard1606]

Thank you Sir,For the education. I hope to meet you some day....

[@AgentJayZ]

I met many folks at Oshkosh 2019. Maybe I can make it there this year.

[@cck0728]

Excellent video. What is the purpose of the holes in the disc and compressor blades? Normally, the holes are in turbine blades for cooling. Thanks.

[@AgentJayZ]

Time stamp. There are no holes in the compressor blades of the Allison 250.

[@cck0728]

@@AgentJayZ Apologies! At 11:30(holes at the root of the compressor blade)and @5:03 , the disc of F-18 contains holes. I mean that. Thanks, if you could clarify.

[@stebro2738]

My son just finished a stint at GE.. Some of the BLISKS he was working on for the new 9x et l were many FEET in diameter. Sooo, , like you're saying, Millions for one engine and who knows how many millions for a repair part. Progress, I guess!!??

[@ericthered9655]

I see. The resonance frequency of the blisk must be above the range generated by the system which I presume is pretty low frequency. Now it makes sense. I could see how a big one would go catastrophic if it hit its frequency at high RPM.

[@41istair]

Have you ever encountered laser cleaning via ablation? I just learned of it via KZbin and it seems pretty amazing and very fast. It is still considered pretty new but patents go back to 1995 for Saint Gobain cleaning their glass molds; then Boeing have a patent from 2016 for cleaning processing tools. Various manufacturers are in on it now and the folks at P-Laser have an impressive client list.

[@7249xxl]

Awsome video as usual! P.s. the background sound is not annoying at all.

[@bogdanradulescu870]

it is the wind

[@ShuRugal]

Just a bit of a pedantic thing here: Tacoma Narrows, despite what we all learned in high school physiscs, was NOT an example of resonance. The bridge was brought down by aerodynamic flutter. The main beams of the bridge were solid-webbed, rather than being constructed beams more typical on structures of that size, and this resulted in flow separation as the wind traversed the bridge deck, causing turbulent flow above and below the deck which caused it to twist itself apart.

[@AgentJayZ]

The flutter was reinforced by resonance. Of course, all the text books might be wrong, and you might be right... ...

[@ShuRugal]

@@AgentJayZ I'm not going to claim that resonance was no factor, but a number of studies on this have been done recently (over the last couple decades) which found that aerodynamic (or aeroelastic) flutter was far and away the driving factor for collapse. But you don't need to take my word for it. bridgemastersinc.com/aeroelastic-flutter-collapse-tacoma-narrows-bridge/

[@ASJC27]

I agree, this was aeroelastic flutter, not classical resonance, though they are related. I remember being given this case as an off hand example of resonance in 'dynamics' class during the first year of undergraduate aerospace eng. degree. A couple of years later in aeroelasticity class it was brought up again, this time with proper analysis, as an example of flutter. The wikipedia page on this also calls out the common place error of attributing this to resonance, claiming that flutter is the cause. They link a paper published in the "American journal of physics" that discusses this old error and the correct explanation. Resonance is a phenomena where an external periodic force matches a natural frequency of a structure, driving it to greater and greater amplitude, potentially until failure. The driving force has to match a natural frequency. Faster or slower frequencies will not cause resonance. Flutter happens when the wind speed exceeds a certain speed (flutter speed). Any constant wind speed above it will cause flutter. No need for a periodic forcing of any frequency. Von-Karman vortex street shed by the bridge was said to have been the periodic force causing resonance. The problem with this is that it doesn't agree with recorded observations. The bridge oscillated at 0.2 Hz, which wasn't a natural frequency of the structure, nor was it the Von-Karman shedding frequency. There was therefore no external periodic forcing. It was in actuality torsional flutter that caused the oscillation. Physical model tests, as well as calculations support this and correctly predict the bridge's motion.

[@grahamj9101]

When the bridge deck was oscillating in that extreme torsional mode, immediately before it failed, it was presenting extreme positive and negative angles of attack to the wind. It must follow that the the deck was generating significant alternating lift and downforces - and stalling at the extremes of the motion? It must also follow that the deck could have been generating alternating vortices, akin to a Karman vortex street, albeit not necessarily the classic vortex street that would be shed by a cylinder in a crossflow. Yes, as a first-year engineering undergrad in 1963-4, I was shown the film clips of Galloping Gertie, and resonance may have been mentioned (I cannot actually recall). I would now be interested in seeing a real-time CFD analysis of the airflow around the bridge deck in motion. If it hasn't already been done, it could make a good subject for a Master's (if not a Doctorate) degree dissertation, together with an investigation of possible palliative measures, up to and including a redesign of the bridge deck.

[@kasuha]

For something to resonate, it needs something periodic to resonate with. So yeah, the flutter was the periodic action that made the bridge move, and resonance took care about individual relatively small flutter contributions adding up to destructive magnitude. It would not fail without either. The bridge was standing there for a while, and only failed when the wind was strong enough to overcome dampening in the bridge construction. But when the wind came, it took a while for the bridge to reach its terminal oscillation amplitude and that would not happen if there was no resonance - the wind was not strong enough to destroy the bridge in a single swing.

[@dozer1642]

When I saw this video it put me into a state of bliss

[@russbrovald5537]

The very large Ti fan blade you showed today had a "Y" type stand for display. How can I get one of those stands. Looks great. Don't need the fan blade. RB in California

[@AgentJayZ]

I made a cardboard pattern to fit the blade root. Gave it to the water jet fab guy next door, and said "can you make it look cool?" Took him five minutes.

[@russbrovald5537]

@@AgentJayZ Wow, a great reply from the world famous agentjayz. thanks a million , Russ

[@RobertBardos]

Great vid always love a lunch chat in jet city. ✌️

[@martinrochefort5476]

I'm gonna go with Bladed Ring or "Bling"

[@cjhodgson3000]

Very well done, but that is normal for you. As far as bean counters go, if it is cheaper to build, the manufacturer's bean counter is happy, and he is hoping the sales team can cover up the more expensive replacement cost from the customer's bean counter until after the purchase. That is some wind you have going on out there. A lavalier mic would be nice, but I have no trouble understanding you with my old, abused, tinnitus afflicted ears, but I use very good equipment to listen.

[@bgm1958]

Re: glass beading. Does that leave a glass residue on the part? If so what do you use to clean it off? Is it as simple as soap and water and a brush or is it more complex like an ultra sonic bath?

[@AgentJayZ]

Leaves a small amount of beads and dust. Blow it off with air, or brush it. For critical clean, rinse it with solvent and a soft brush.

[@f.n.schlub]

Check Bladon turbines for modern blisk manufacture.

[@alaasleem2149]

Thank you sir for your golden words... Frequancy is agood pranch to explain.. I think you will be good ENG if you make video about all jet parts Frequances

[@boomer9900]

So a hard drive typically spins at 7,200 rpm and is aluminum. The "bling" at 50k+. Assuming both are balanced, what allows the compressor to spin so fast. Is it a materials thing, a shape thing, or something else? The diameters of these two are not that far off.

[@KenLeonard]

A hard drive is spun with an electric motor and at ambient temps. A turbine is driven by forces as high as extremely strong materials can handle.

[@AgentJayZ]

The hard drive has a need to be dimensionally stable, so it is stiff and light. The compressor parts shown here have a need to go fast enough to achieve the aerodynamic performance of the airfoils. They are made of steel, and are hundreds of times heavier, and thousands of times stronger than the hard drive discs.

[@perwestermark8920]

Normal server hard disks are available to at least 15k rpm. But they require very stable surroundings. People have done experiments where it's enough to scream near a server array to see the transfer speed drop. All because of the very extreme positioning requirements of the disk heads. The disks also requires lubrication and rwgularly moving heads because the turbulence between head and disk results in wear.

[@Alex4n3r]

What measures are used today to reduce vibration/fringe patters of the blades?

[@markbell9742]

I think you like saying 51,900 RPM about as much as I like hearing it. Cheers, Mark

[@AgentJayZ]

Probably more. I think of the times I was on my race bike, screaming down the front straight, bouncing off the rev limiter at 11 thousand rpm, and then I giggle inside when talking about this engine.

[@markbell9742]

@@AgentJayZ Yep, you got me there. Cheers, Mark

[@timyarrow8844]

Been gone for a few years from this channel, and see you've got new toys (to me) to play with. While telling us how expensive a Blisk is, care to actually mention the price? On another note, how do you not look even a day older than the last time I saw your mug?

[@AgentJayZ]

The way it works in this industry is... The only way to get the actual price is to commit to buy one, after filling out a customer credit application.

[@zapfanzapfan]

Do you know of any blisk used in the turbine section of a jet engine? I've held one meant for the turbine powered fuel pump in a rocket engine. Not sure if it was a prototype or something in production. The outer circumference was a continuous ring with a knife seal. It looked really complicated to manufacture.

[@AgentJayZ]

The turbine in Darren Duncan's J44 turbojet, which was balanced here at Jet City, is a blisk, if I remember correctly.

[@joedanay949]

If you choose to use that component in a rocket engine, I'd recommend staying far away, behind and under cover when you light that candle!

[@zapfanzapfan]

@@joedanay949 As opposed to the normal procedure of standing right next to a rocket engine when you fire it?

[@joedanay949]

@@zapfanzapfan Choose your own misadventure if you're building rockets out of scrap parts! Stay safe:) The 7th stage of an Allison 250 compressor is centrifugal. An automotive water pump easier to find and less expensive. What type of fuel do you intend to use? And what altitude are you hoping to achieve? Also, what flow rate will you require?

[@zapfanzapfan]

@@joedanay949 That component is for a 100 ton thrust hydrolox engine. My profile image is a surplus engine nozzle from the previous model turned into a park bench, probably the most expensive park bench ever. When the engine is lit the closest human is in a reinforced building 3 kilometers away.

[@Stummel01]

why do the compressorblades have "cooling"holes in them? is iht just weight reduction?

[@yabojabo8578]

Not cooling holes. They're there for weight reduction and probably balancing.

[@JimWhitaker]

To allow cool air to flow from hub to tip and exit there.

[@AgentJayZ]

Jim, fan blades run at inlet temp, which up there is about -50 to -70C. They are not cooled.

[@johncheresna]

I see a lot of jet engine parts and pieces in sci-fi shows and movies. Has your shop ever been asked for old parts. yeah its a stupid question .

[@AgentJayZ]

I was once asked to record some engine starting sounds for somebody called "Skywalker Sound"... weird name.

[@dennisbailey4296]

@@AgentJayZ that's only the major Sound Studio for Star Wars some connection with Spielberg and George Lucas. Wow

[@AgentJayZ]

Dang! I forgot to use the humor key...

[@grahamj9101]

@@AgentJayZ Since the subject of suspension bridges has arisen, one of the sound effects for the original Star Wars movie was that of the main suspension cable of the Severn Bridge being whacked. I can see the bridge towers in the distance from my home, and I used to take a walk across the bridge before this lockdown was imposed. Its design was novel, in that it departed from having a deck with a deep open girder construction. The deck has a shallow box section, the design of which was extensively wind tunnel tested before it was adopted, with Galloping Gertie's failure very much in mind. Incidentally, the river estuary beneath the Severn Bridge has the second highest tide range (over 40ft in old money) in the world. So does it have any connection with jet engines? Yes, one of the towers used to have a microphone for noise recording of aircraft being test flown out of Filton airfield, just a few miles away. The airfield was closed some years ago, and they are now building houses on what was the runway. And there's another connection with jet engines and the Severn Estuary, which I've mentioned before. A Bristol Britannia prototype had to ditch after the main reduction gear of a Proteus engine failed, causing an uncontained failure of the power turbine, which resulted in a fire in the wing. Fortunately, it was low tide and a safe crash-landing was made on the mud.

[@hisheighnessthesupremebeing]

The last one was Bling (a bladed ring)

[@lasajlasaj660]

i always thought the looseness of turbine blades would make them vibrate more and wear out faster due too the slight movements so wouldn't a solid turbine be more stable rather than separate blades also if i am wrong couldn't there be some high temp rubber applied on at least the compressor dove tail to lower that stress put on them

[@grahamj9101]

At power conditions, dovetail and firtree roots are substantially 'locked up'. In any case, anything as soft as rubber would probably be extruded out very quickly. Having said that, in the 1980s, in order to overcome a flutter problem, I put rubber damping blocks under the platforms of the fan blades of an engine, which I won't identify. As far as I'm aware, that engine is still flying with them. I also put a damping compound into the inner fixings of the IP compressor stator vanes of the Industrial RB211, back in the 1970s.

[@lasajlasaj660]

@@grahamj9101 very cool thanks for the answer

[@johncheresna]

FYI a new turbine engine has been developed, clean sheet. I am not allow me to post links. I am their bad books. Look up 'Hill helicopters'.

[@AgentJayZ]

So... you are saying that my standards are lower, and you're "slumming" ? Eh? I ain't lookin' up nothin', bub.

[@johncheresna]

@@AgentJayZ What! I am just informing you of a clean sheet turbine engine that has just been developed. That according to the manufacturers is much more efficient. If I try to post a link, YT will not allow me, because I am in their bad books.

[@AgentJayZ]

OK, I did take a look. Looks like a really nice product. hopefully I'll see one overhead soon. Do we want to know why YT is mad at you?

[@dennisbailey4296]

@@AgentJayZ Now that you've tweaked our imaginations what's up?

[@johncheresna]

@@AgentJayZ Because I am blunt and tell the truth. I have said negative but not bad remarks about Trudeau and the like. (edit, things as simple as 'spend. spend, spend") They took down 2 other channels and will not let me start another. Cancel culture has gone insane.

[@johnmelling9950]

Jay, what's the difference in an aircraft spey and an industrial spey with regards to the fan? Surely you would not have a industrial spey bypassing any air?

[@AgentJayZ]

1 It's bigger, to produce the bypass flow. 2 See (1).

[@grahamj9101]

I saw the design of the Industrial Spey progressing on the next section in the Design Office at R-R IMD (I was working on the Industrial RB211). The engine was based on the Allison TF41, which was a derivative of the Spey. The fan was was 'cropped', effectively turning the engine into a turbojet. For the first development engine this was done simply by cutting down the fan blades, while still using the TF41 fan casing. This was filled, using some blue plastic compound, to reduce the annulus outer diameter. I recall the Chief Development Engineer complaining in an engineering meeting that the thickness:chord ratio of the cropped blades was wrong, and that the tip sections should be thinner. I told him that they were "an accident of nature".

[@AgentJayZ]

graham: another priceless nugget from someone who was actually there. Thanks!

[@grahamj9101]

@@AgentJayZ I think that I've actually told this story before on your channel, AgentJayZ - but then I know that I've repeated various stories from my career and from my knowledge of the history of the jet engine on this side of the pond. Going back further into my career history, following my apprenticeship, I worked on the Marine Olympus power turbine and on fuel systems. Following that, I was involved in early project design work for a Marine RB211, as a replacement for the Marine Olympus, working for Bill C***, one of three very experienced Section Leaders in the Design Office at R-R IMD. He had actually worked for Frank Whittle during WWII, having started as an apprentice draughtsman at British Thompson-Houston, from where he was seconded to work for Whittle at Power Jets. He told me that Whittle was a difficult man to work for, but then he was under enormous stress and suffered nervous breakdowns, which he acknowledged in his book, 'Jet: the Story of a Pioneer'. The Marine RB211 project went down the pan when R-R went into bankruptcy in February 1971, and a low-risk project for an uprated Industrial Olympus was launched. It was then that I made a nuisance of myself and, with no experience of turbine design, I was allowed to design the LP turbine blade for the Olympus 'C'. Following that, design of an industrial, rather than a marine version of the RB211 was reinstated, and I returned to working on the project as Assistant Project Design Leader, with Bill C***. When he moved on, I become Project Design Leader and, in due course, I became Project Design Leader for an industrial version of the Olympus 593 in Concorde. That project was cancelled in around 1979, but it resulted in me being noticed by R-R Bristol, and the rest is the second half of my career history at R-R Bristol.

[@josephspratt2055]

I was watching a video on Rolls Royce engines and there was a segment where an A380 sporting RR engines had landed and one of the engines would not shut down. It didn't "runaway" it just wouldn't shut off. They brought the firetrucks out and started trying to 'drown' the engine with water. I was yelling at the screen, "that will never work". Then they sprayed it full of foam, that did work but did God knows how much damage. Isn't there an easier way to shut down a jet engine even if the cockpit controls go out?

[@AgentJayZ]

The fuel needs to be shut off. There is no convenient valve to reach, and the fuel systems are so integrated, it is very difficult to get at, and impossible to quickly disable. Fuel pumps are mechanically driven by the engine, and totally inaccessible. The entire fuel system is specifically designed to "not easily disabled". I believe that story was not about a normal landing, but an emergency landing where there was damage to the wiring to that engine.

[@grahamj9101]

I think that you are referring to Qantas flight QF32, the No.2 engine of which had an uncontained failure of an IP turbine disc back in November 2010. The aircraft returned to Changi and made an emergency landing. There was damage to the wing, including to the wiring harness to the engines, with consequent loss of control of No.1 engine. Its power setting was effectively 'frozen'. Any damage to the engine was minor, as compared to that done to No.2 engine and the wing. The aircraft was repaired and returned to service in April 2012.

[@CaptainSwoop]

@@AgentJayZ Yes, it was an un-contained engine failure on a QANTAS A380. Landed very much over weight due to inability to dump fuel and the damaged fuel system probably caused the shut down problem. Another excellent video ... I enjoyed that ... thanks.

[@travisk5589]

I barely hear the space music. It's almost like it's only in my head

[@tomlompa6598]

I don't think any casting would stand up to what that small disc unit needs. Normally, a compressor disc is a forging of some sort. Some kind of titanium alloy. Now that I think about it, there's a good chance that my workplace made(forged) all those compressor discs and rings. Our main contracts are in aerospace.

[@frommarkham424]

I first thought that the sound caused by the heavy wind was music

[@serbianknights4988]

Hi mate I looking for to buy of ebay cj610 for the project. Cen you please give me an idea how much cen cost me overhaul of that engine and where I cen ending up with cost wise? Another question I own BD5 with B wings. How much cen cost TSR-18 with logbook? Tnx

[@trumanhw]

I'd imagine you could actually repair a blisk using CNC and balancing it ... no? Let's call it a BLASER.

[@lisandroantoniorodriguez9242]

LOL I was mechanic of those old engines. Is it a C20?

[@AgentJayZ]

We have a C-18, and a C-20.

[@lisandroantoniorodriguez9242]

@@AgentJayZ I'm looking forward to finding out what happened to the Iroquois. I dedicate myself to studying philosophy and history of engine design and that fascinates me. Nine months from the drawing board to the test bench. The Russians took seven years with the R-11 It is very sad what happened.

[@lisandroantoniorodriguez9242]

@@AgentJayZ I was watching again your video of the Iroquois from 11 years ago. What finally happened? Missing blades can be cast very easily today. The material of the turbines was equiaxed IN 713 vacuum cast, the most common alloy for Diesel turbos. You can exchange it for IN 738 (old T-56 blades and thousand of big blades from old industrial turbines) or even from Mar M-247 (the best commercial equiaxed alloy without rhenium and used in gasoline engine turbos). These alloys could last forever in the mild operative conditions of an Iroquois. The titanium blades can also be cast, since the stresses are very small in this engine and that is how these were originally made. It's a shame that the factory here that made those things closed 25 years ago. An Argentina that nobody remembers anymore. We came close to casting the turbine blades for the Navy Tynes in 2007 but it happened again. Corruption kills everything. You are in Canada and you can go to multiple workshops there and elsewhere that make those parts. You just need a 3D CAD model for them to cast them in using lost wax in whatever you want.

[@AgentJayZ]

All necessary parts are in boxes in our national museum in Ottawa. We have been registered as an aircraft technology museum, so we have access to them. Politics make things difficult, and the owner of this engine ( not me! ) appears to be losing interest in pursuing the restoration. I have no control over these factors.

[@lisandroantoniorodriguez9242]

@@AgentJayZ You know, there's a resurgence of these engines. Of course, with advances in materials, aerodynamics and cooling (Iroquois is uncooled). However, these architectures return to the scene with supersonic business jet projects, where the pure turbojet offers high efficiency. So far all the proposed motors are very old rebladed military low derivation turbofans.

[@doctorrobin3040]

Bit windy outside eh?

[@VladLordDracula]

Windy out there... :)

[@georgerobartes2008]

There's a good video on You Tube called Blisk Manufacturing by Advanced . The hi pressure lost wax system is becoming superseded . My old physics teacher said there is no such thing as centrifugal force which is correct .

[@AgentJayZ]

Yes, your physics teacher made a good impression on you. Centrifugal force is a conversational term, not a technical one.

[@daos3300]

people, centrifugal force is a thing. it's not an external force, but is experienced in a particular frame of reference, due to inertia..

[@georgerobartes2008]

@@daos3300 Newtons 1st law ' A body will continue in a straight line etc'. Basically you have Centripetal Force and the opposite to that is the Reaction Force . Centripetal Force in this application is the external force .

[@mxcollin95]

Agent jz do you guys ever rebuild PT6-60A(s) by chance, or any PT6s for that matter???

[@AgentJayZ]

Have not had a PT6 in the shop. Good engine.

[@mxcollin95]

@@AgentJayZ ya there’s a heck of a lot them out there!

[@sarniaaircraftserviceinc.7610]

What would be the ideal (jet) engine to put in a BD5j?

[@AgentJayZ]

The Wiki page is way too long for me to read at this time. You need a very small engine. Williams industries has the engine you want. A few hundred grand a piece. Not generally available to the public, but nowadays, I'm sure they would sell you one.

[@sarniaaircraftserviceinc.7610]

@@AgentJayZ Guess I am sticking with the Suzuki G13. ROFL

[@joecichlid]

Double/double? I don't think you can get one of those at Timmy's. lol

[@karlgoebeler1500]

Ring for sure But what girl would want one??

[@mlrocketeer8961]

Have you checked out the book chrysler’s turbine car by steve lehto

[@j.muckafignotti4226]

That sure is shorter than any CF6 N1 fan blade I’ve ever seen.

[@AgentJayZ]

I've got a polished-up one in the shop. I also gave one away for my 500th video contest a couple years ago.

[@j.muckafignotti4226]

I’ve got two 767-300’s coming in a little later, I’ll try to swipe a couple of -80C2’s for you. There’s lots on the N1, they won’t miss a couple…

[@karlgoebeler1500]

I have the Data packages for those engines but their in New York at this time And I'm in Florida

[@gordonlawrence1448]

Emerald use (or did use) spark erosion for part of their turbine production process as far back as 1985. www.emerald.com/insight/content/doi/10.1108/eb036163/full/html?skipTracking=true and Fraunhoffer specifically mentions some processes for the manufacture of Blisks that can be done with spark erosion: www.ipt.fraunhofer.de/en/Competencies/processtechnology/water-jet-electro-erosive-machining/electrical-discharge-machining.html I am under the impression that the whole process can be done with spark erosion but that it;s inefficient. I think (but I'm not sure) that the blisks are machined to the approximate shape of the finished item then the excess metal is spark erroded off.

[@user-rc8bb7yb1e]

cool btw

[@tonyalto1014]

I'd vote blacer🙂

[@brianevans1946]

A Blo-nut.

[@tkmotors991]

A disc with a hole in it🙃

[@robertriquelmy7193]

Fewer parts please

[@engineerinhickorystripehat]

Haaaaachoooo!

[@johno9507]

A lot of those are drums not discs.

[@iflydachoppa7110]

Hub

[@KozmykJ]

Blinger

[@trumanhw]

AHH!! Someone who knows!! There's no such THING as CENTRIFUGAL FORCE. centrifugal is just a _situation of centripetal_

[@pb2959]

You keep saying it's very expensive... what kind of expensive are we talking about here?

[@nde-mt2yc]

11 months and counting, new and rebuilt parts. Probably $300,000.00 on the low side...

[@Dh09Cloud]

dude- if ur an engineer bro make like black panther or somthin man-

[@86abaile]

The sci-fi hum is the back ground was super irritating. I had to stop the video.

[@AgentJayZ]

I find silence to be super irritating.

[@daos3300]

@@AgentJayZ lol