Worlds FIRST axial flow model jet engine

This is the first commercial model jet engine to feature an axial flow compressor, the compressor section is a 4 stage axial with a single stage axial turbine, this prototype was designed to prove that it could be done in model form.

[@peterjones6733]

Brilliant. And no irrelevant background music!

[@ArcturanMegadonkey]

Irrelevant background music is horrid on any youtube video where it's not necessary! and it would drown out the music of the engine! I have a few other turbine tests on my channel and there will be more in the future. all the best and thanks for watching and commenting Paul

[@peterjones6733]

@@ArcturanMegadonkey Someone with the same views, And loves engines... heaven! :)

[@stephenlarkin3690]

Oh, there was music alright.

[@jdjdjdif9777]

Dou you want to recommand one?

[@bernardolozano7429]

You sir are a genius the only jet engine models I’ve seen so far have centrifugal compressors. Godspeed!

[@erikjohnson2976]

Damn! That is truly impressive engineering and machining. Beautifully done. This takes microjets to the next stage (actually, four stages).

[@thethirdman225]

Next project: afterburner!

[@Yuri-gg6nv]

It's just injecting aditional fuel into the Combustion chamber... nothing special

[@jamesburleson1916]

@@Yuri-gg6nv Afterburners inject fuel into the exhaust, actually. They rely on unspent oxygen in the air, which is why modern supersonic jets use low bypass turbofans, rather than turbojets. The bypass air delivers much more oxygen to the tailpipe allowing more fuel to be burned in the afterburner, and thus more thrust.

[@midwestsirens]

YES

[@DiscoR53]

TheThirdMan Then a variable nozzle.

[@Pieman6711]

@@DiscoR53 Have you put together an AB? Jesus, VENs are a pain in the ass to assemble. Don't get me started on pri flaps and seals, or the actual VEN plates themselves. Not to mention you're gonna need a pressurized system to actuate all the actuators, and a transmitter... Anyways, fuck VENs. Sorry, salty sailor here.

[@TheFlyingBusman]

Well, I’m impressed on several levels. Firstly the incredibly precise engineering to scale this down but then the physics of getting it to fire up and run so well. A credit to you for building such a fab little turbine.

[@ArcturanMegadonkey]

At the time of running it did surge at a point but I understand now it has been sorted.

[@waspsnest]

@@ArcturanMegadonkey only partly, it can run faster before it starts surging but its still there.

[@kaboom-zf2bl]

@@ArcturanMegadonkey what was the thrust at max throttle ... RPM has no meaning beyond it spinning fast ... how hard it pushes (THRUST) ... is what matters

[@RobWhittlestone]

Beautiful construction. What are the specific data? Weight, thrust, N1/N2 max, consumption etc. Cost? ;-) What is the lubrication solution for the bearings? Service life? I would love one. It would sit in the lounge and I would run it every day. My wife will be delighted! All the best, Rob

[@hugostiglitz6914]

Don't think it would have an N2, I think it's a single stage motor!

[@autogolazzojr7950]

Looks like a single spool engine

[@bruceburns1672]

Must be great to have such an understanding wife , you are a lucky man , usually at your age they are well gone after getting half the money or more from the sale of the house you broke your back and worked on every weekend for 50 years , but they do need to discover themselves in Tibet or something after the hard life in the Western world bringing up one child .

[@2x4barrels40]

@@bruceburns1672 Yes our court system just loves to bend over men . There is no law " YOU GET WHAT YOU WORKED FOR " . They are their own boss all day long and your boss all night long .

[@ArcturanMegadonkey]

Sorry for the late reply (2 years, I've been busy) We're going to be test running the engine again in the next few months so I'm going to take all your questions and a few others on here and get them answered via subtitle when the next video is published.

[@whtstr2133]

Now THAT is a beautiful little machine. I've seen so many homebrews that this jet engine makes look SO bad. Heck the fire control alone is so badass, it's not even funny. Thank you for showing this. I feel justified being so critical of my own designs to such a degree, I'm motivated to build again. You are a lucky dog, having such a work of art that sounds just as beautiful as it looks. I'm truly astounded at such beauty. : )

[@ArcturanMegadonkey]

Thanks for watching and your nice comment

[@zebby60]

Massive hat tip to the designers, engineers, manufacturing, machining. Bloody impressive

[@thatsoundslikeblue]

Awesome little jet. Also makes me grin when I think of the APUs in passenger jets as just glorified leaf blowers. XD

[@xButterSchmalzX]

you have some balls to stand next to it during a test run :D imagine there is a material weakness at 95000 rpm and this thing blows up

[@ArcturanMegadonkey]

YlnMhn we were about 20yds away and left camera rolling

[@davecrupel2817]

95,000 rpm???

[@youtubestolemyhandle1]

Daniel Cannata Yes

[@100GTAGUY]

Daniel Cannata I've seen some of these mini turbines spool as high as 130k RPM during full power run ups. They're crazy lil things haha

[@mikeconnor3602]

@@altyee i was thinking the exact same thing, never stand on the side.

[@cr6925]

Amazing achievement! That engine looks and sounds awesome!!

[@Gkuljian]

I wondered when someone would do this. And that's a lot of years of wondering. Beautifully done.

[@leokimvideo]

Thank God for leaf blowers I'm sure Mr Dyson could market this in some way

[@AgentJayZ]

It actually sounds a bit like a RR Avon. Nice vid.

[@ArcturanMegadonkey]

Thanks mate, funny thing I'm a sub of your channel and if anyone thinks it sounds like another engine it'll be you. all the best Paul

[@FirstLast-tx3yj]

@@ArcturanMegadonkey any thrust figures and weight??

[@davem5333]

A big tip of the hat and pat on the back to anyone who makes a jet engine that runs regardless of design particulars. The design and construction of these are very intricate and complicated. You have my awe.

[@keukenrol]

Those small jet engines are just lovely to see and hear. A true masterpiece indeed!

[@coriscotupi]

At last a model jet engine that doesn't sound like a dentist's drill.

[@flaplaya]

20 really jealous haters gonna hate.. That is a working piece of art.

[@licensedmusicforyoutube1704]

1:00 Buy This Engine via 10% discount coupon code brmo www.stirlingkit. com/?ref=myrctoys

[@RandoWisLuL]

it sounds so good......i love the sounds of all jet engines but this design has such a satisfying clean sound.

[@johngibson9680]

Wow. Just Wow. You have to know what precision crafting is involved to appreciate this, people. This is very different from other model jet engines.

[@shaunwest3612]

cool video,sounds awesome😀

[@hardwareful]

I'm rather sure AgentJayZ would love to have one of these as a model / for exhibition

[@Chainspike101]

I love the little ITT gauge in the back haha

[@fishingWithHector]

I kept trying to come up with how you would go about making a diffuser when you're building a model jet engine. And then I saw this video and saw all you did was make the combustion chamber a larger diameter, I have no idea why that didn't hit me. Amazing video

[@brandonb417]

What kind of thrust numbers are you seeing from this?

[@petea2721]

3

[@tokagekage]

I'd say it's more of a 4

[@rjs2400]

Don't expect an honest answer. here the thing is set up on ball bearing slides that EXACT purpose, and have the scale located, but oh, no camera shots of the reading. Just "if I recall" loll

[@sbkenn1]

Self sustaining noisemaker ?

[@ohwell2790]

That is all some people are about is making noise, so let us MAKE noise.

[@pauljs75]

Somebody finally pulled it off! I thought there was trouble getting axial compression to work at that scale, since the majority of model scale engines seem to have a centrifugal compressor which only gos to axial flow at the expansion stage. The burners still seem large relative to the overall engine though, no other way to drop velocity in that volume while keeping pressure before the reaction nozzles/vanes? Any improvement in function, or are the centrifugal style engines still better?

[@andreasvogler1875]

They are cheaper since centrifugal compressors can be cast or cnc milled. Spark erosion is an expensive process.

[@scrfce123]

You can mill axial discs from certain billets, too. The reason that turbine wheels are either spark eroded or cast is because inconel and other high nickel alloys are too hard to mill in a practical manner.

[@EdwardJerezG]

At this scale, centrifugal compressors are actually more efficient than axial ones, and since they are lighter, cheaper to produce and relatively easier to design, there is simply no reason to use axial compressors on model jet engines. The only problem with centrifugal compressors is that their flowrate is lower for a given front area, but you can make up for the thrust loss by using a turbofan configuration instead (might be wrong on this, please correct me if I am). A single stage centrifugal compressor will probably achieve a higher pressure ratio than the 4-stage axial compressor used in the turbojet from the video (although I would need numbers to be sure about that).

[@danvandertorre9280]

do you know were there is a site I can go to or some one I can talk to too up size one for an ultralight I am going to build .

[@m.berrada3696]

another guy managed to make a self sustainable enging with an axial compressor. i think his channel is "niffi2"

[@paulstovall3777]

Beautifully designed and built piece of machinery. I used to work on the big Pratt & Whitneys and G.E.'s. I love jet engines. Thx.

[@chrisspekking8535]

You’ve done yourself proud. Brilliant job.

[@ArcturanMegadonkey]

Wasn't built by me but a friend and yes he has done a brilliant job

[@tragictheory]

Awesome work!!! However this is the internet and we will be needing afterburners. :)

[@waspsnest]

shouldnt be a problem, ill get onto it when I get a minute

[@neardood1]

Very cool.. How much thrust does it produce?

[@MCAroon09]

ALOT

[@yamilandres]

man.. I love the sound of that small engine!

[@davegtar]

Genuinely sounds like a hair dryer, Pretty awesome though :) I'd really love to see a model turbo fan jet

[@Thompsolonian]

This isn't the first, I worked at a concession stand for Scouts at LEAST 15 years back at Roseville, MN where one of the members of the model aircraft club produced axial flow jet engines for models, and yes, he sold them to people, ergo commercially avaialble.

[@waspsnest]

do you have any info on this. i saw one in a magazine article called MAT22 in the mid 80s but never saw anything more than that one article.

[@ArcturanMegadonkey]

think I got some drawings for mat22 somewhere

[@waspsnest]

I had the mag for years, dont know what happened to it. (the magazine or the engine)

[@michaelmcneil4168]

What is the power output of this thing. The initial problem never fully solved by Hooker's management was that the axle front end was free to wabble causing compressor instability. I think the solution was to add the modern propeller to even the throw, thus producing the High Bypass Turbo Propeller? Ernest Hives was not happy with the way things went and found that Hooker was burned out. he forced him to take a leave of absence but Hooker was too upset by then to see the problem. So he left Rolls and set up the company that made the Bristol with all the eventual problems caused by Briitsh political mis-management. It's a nice machine and I would like one but it doesn't demonstrate the actual problems with axials; which is: The nutation of gyroscopes. butikov.faculty.ifmo.ru/Applets/Gyroscope.pdf The origin of nutation that accompanies forced precession is ex-plained in detail, with an accent on..... Imagine trying to ride a bicycle without wheel rims just a mass of spokes (like a wire brush) they are OK when free to spin but impossible to control in a corner at speed. With a vehicle moving off the straight line, the turn causes it to cant over or roll. When that happens in an engine the compression leaks. I think that must be something similar to engine knock and noisy plumbing.

[@garrycoleman2739]

Thomps olonian

[@waspsnest]

nice motor, ill have to get one of those

[@ArcturanMegadonkey]

you'll need lots of money lol

[@DandSCreations]

I'll just run down the the Wal-Mart... It's in the only example in the world section.

[@waspsnest]

nah ive got 5 more like it at home

[@DandSCreations]

not AXIAL flow

[@waspsnest]

no ive only got 1 1/2 of those

[@jeylful]

Awesome model, mate! Impressive

[@byrondot]

An impressive archivement. Kudos to all involved.

[@gmanbuilder9843]

Very nice!!!! Now put it in a plane!!!

[@KarriKoivusalo]

Stellar work, truly a remarkable feat of engineering and high precision handicraft! Four stages isn't a whole lot for axial compressor, I wonder how much is the overall pressure ratio?

[@waspsnest]

design PR is 2.5:1 but its only acheiving 2.3 so far

[@KarriKoivusalo]

Cool, I guessed between those figures :D

[@alexanderbonardi4514]

Now that you have axial flow you need to work on a proper annular combustion chamber !

[@gordonwbell]

My god that thing is pure bliss! I’m currently working on my own version, started in 2012, shelved it, then recently back at it, although I’ve being using a lot of formulas from Tomas Kamps Model Jet engines book, a lot of the gas theory I’ve taken from my school days of Mechanical engineering, and google, but long story short, I think I’ve managed to make the math work for a single stage compressor, with a 1.4 compressor ratio. Although I realize I still have a lot of engineering still to do, until get any where what you’ve built. I’m also trained on using UG NX4, solid modelling software, and did a first year machinist apprenticeship, although that’s several years ago now. Would love to collaborate on something. They now have 3D printed carbon fibre technology that’s fairly cheap now a days, for a compressor. Anyways cheers

[@mnshp7548]

this is amazing, the sound is great

[@StormSilvawalker]

is this a radial or central combustion chamber system and if it is radial is it multiple segments or just one chamber? whilst it is a beautiful machine and a truly amazing accomplishment did not "niffi2" build an axial flow model jet engine 2 years ago?

[@philippwetter]

Thats what I thought too! Niffi2 got it to work 2 years ago and with 6 Stages

[@waspsnest]

its an anular combustor. Idid write to mr niffi2 but no reply yet

[@waspsnest]

the actual first run of this compressor and turbine was a good 5 years ago but it originally had a centrifugal compressor 5th stage and two stage axial turbine. I do have a vid of its first run on here but its listed as private. i built this mostly to rescue the axial rotors and prevent them ending up in the scrap bin, also to prove to myself that a small fully axial machine can be built that runs well and starts easily. the next (much cheaper) version is already under development if only in the back of my head for now. will be real and available one day

[@StormSilvawalker]

+tigercat scratch awesome! do you have any advice for someone starting to build one (where to find the math such as ratios of intake d to combustion chamber hole d)?

[@calfpv5973]

Hi, I'm interested in building an axial flow turbojet myself and whilst I doubt I'm a whole lot further along the line than you are, if you haven't already seen the Rolls Royce Jet engine book you should look for that, as well as the resources on the MiT and NASA websites which provide a few equations. That said, I am also struggling to find equations.... the axial flow compressor article on wikipedia has a few but it's certainly a huge task with a LOT of research required. Hope that helps a little...

[@grahamj9101]

Sorry, no Pan Galactic Gargle Blaster: I couldn't get a booking at the Restaurant at the End of the Universe.

[@ArcturanMegadonkey]

lol nice one

[@lasersimonjohnson]

+agentjayz is on his way there too...

[@grahamj9101]

How about meeting up with Zaphod Beeblebrox? As they say, "Two heads are better than one!"

[@robertvorster8933]

Oh my word. Love this kit!

[@ramonmedina1974]

fantastic work!

[@dredrotten]

Wow that is so Excellent.96,000rpms makes me think its a very expensive bought one,I mean how would you balance each turbine blade to those specs in your shed?

[@waspsnest]

where would you buy it from? they were ballanced on the Sheneck ballancer that sits in the corner of the build area

[@glendooer6211]

How many minutes in RPMs? 60??

[@michaelmeyer6306]

Is this a kit you bought or did you design and manufacture it? Don't get me wrong, if it is a kit it still requires some skill to assemble all the way to the running stage. What does it use for fuel? Have you measured the thrust and figured out the thrust to weight ratio? I'm a 20 year USAF jet engine mechanic and that vid is awesome!!!!! So many questions!!!!!

[@ssss-df5qz]

I'm guessing not a kit. It looks like a really high quality kit, with a load of design and development behind it, but something about it is too good for any kit to come close. If this is a restricted budget hobby garage build out only stands to make me appreciate it so much more. The sound alone is pitch perfect and you just sense how well balanced it is.

[@michaelmeyer6306]

ss ss I agree with you, I'm hoping the owner answers me cause I have many more technical questions to ask. Like: what metal is the turbine made of to withstand the combustion heat and the centrifugal force of 95K RPM? Like you said it looks to be extremely balanced. I'm in awe of this.....

[@ssss-df5qz]

+Michael Meyer - not looks balanced, "feels" balanced. It's hard to explain, I work a lot with cars and trucks and you just tune in to sounds and vibrations, like a sixth sense. It's like a full body sensory thing. When everything is balanced and audibly smooth.

[@ssss-df5qz]

+Michael Meyer - it must be titanium? I have no idea. My friend has a little blade out of a Concorde engine.. about 6 inches it is, titanium, precision, light. They put up with a lot either way so need to be strong.

[@michaelmeyer6306]

ss ss No looks, if it wasn't everything on that stand would have been jumping around. Titanium is what was used on the engines I worked on. Pretty expensive though, pretty hard to fabricate with too. I wonder if it has any stall control? The TF-33 engine on the B52-H would stall with even a mild crosswind or if you moved the throttle too fast. There was even a button on the yoke to manually open the bleed valves if the engines were stalling. With that small inlet probably not a big problem.

[@DistractedTrader]

that shutdown sound though.. music to my ears!

[@thesquisheee]

Now that is a thing of beauty. Looks like you're getting a bit of a hotspot at the bottom of the turbine tho.

[@waspsnest]

thats from starting with compressed air, it dosent spool up as far as with the blower so had to drag the speed up with the fuel

[@JamesHurd]

Quiet little thing isn't she. not like other RC types! very nice bit of kit tho..

[@waspsnest]

yes, very little compressor whine. there are 250 blades in there so Im wondering if the pitch goes beyond human hearing range. all I can hear is the rush of air going down the intake. its all completely drowned out by the leaf blower and thats only running at idle. the only idea of speed i get is from the rpm sensor or pressure gauge if its attached.

[@ristomladich246]

more then likely.

[@CradyLab]

Soooooooooooo pretty!

[@daneshnayak5605]

CradyLab fuelinjectiom

[@UsherLinder]

Exquisite building and much congratulations on your build!

[@steventhornton4716]

Very impressive little jet well done mate

[@ArcturanMegadonkey]

I think Phill who built it is happy with it

[@zavatone]

World's first. Worlds = more than one world

[@henryscp318]

u know that" 's "means "is" because so u wrote "World is first"

[@siratthebox]

That casing doesn't look strong enough to contain a blade failure.

[@waspsnest]

snapped blades dont take much to contain them, its been tested on a seperate compressor rig. its broken turbine discs that could have a chance of coming out the side, very unlikely for the compressor end though

[@peterschiller2451]

Fantastic sound, like the big ones. To make it perfect it should have an afterburner. That would be the icing on the cake. First rc jet engine axial flow with afterburner. Nevertheless, great work !!

[@xtamared]

"Holy shit" is an understatement. This is seriously impressive.

[@sunsheep257]

this isnt the first RC axial compressor Turbine.... The title is misleading. Edit: saw the info: “commercial“ - ok still misleading title

[@saito125]

Mind posting a link to the first one?

[@rogerturner5504]

What is wrong with you? Why can't you just say 'Brilliant achievement - well done'. I agree with saito125.

[@saito125]

Roger Turner , this behavior is typical of no-doers. They sit, watch and wish they could. But they can't.

[@ioaircraft]

comment is still accurate. it is not the first axial flow turbine. i have the first posted on my channel. and i am definitely a doer. one of the most known in rc jets, on planet earth. thanks.

[@ioaircraft]

man, that brings back memories too. posted that video 5 years ago. LOL

[@brysonpassarella7671]

U.S. Air Force would like to know your location

[@ArcturanMegadonkey]

The designer of this engine is hunted by many engine manufacturers

[@keithnoneya]

That was awesome. Very talented engineer and machinist i'm sure. Thanks for sharing it with us, always wanted to build one. Best Wishes n Blessings Keith

[@mauricetucker6354]

that spool down is so sweet and epic

[@GG-sw4ws]

is that hemlock behind the engine?

[@waspsnest]

who/ what you on about mate?

[@nefariumxxx]

I noticed too and yes I think so...

[@waspsnest]

the plants? sorry if its not got a turbine attached I dont have a clue about it

[@nefariumxxx]

tigercat scratch useless trivia perhaps but yes, they are poisonous: www.kingcounty.gov/environment/animals-and-plants/noxious-weeds/weed-identification/poison-hemlock.aspx

[@nefariumxxx]

Yeah we used to see it all the time as kids. I remember it had a spicy kind of smell to the flowers. Fortunately not an appetizing smell or we might have eaten it. ha ha.

[@rinzl3rs349]

considering this is not the first. hate when people put worlds first. fucking click bait

[@DSTEngines]

Nice shut down noise. love it :)

[@RDCST]

For a few seconds I thought that I was about to see the first table that cross the sound barrier.

[@PetesShredder]

Make a model turbofan!!!

[@bpresgrove]

There are a few videos out there if turbo fans I think. I though someone built a twin engine. Could be wrong.

[@Tomtom88983]

Technically a turbojet, a turbofan has bypass air whilst a turbojet like what you see in this video does not have bypass air (air going around the engine via an external fan)

[@DSTEngines]

Ewald Schuster build one! Since a few weeks my Turbofan engine is ready to run on idle. Still idle because the fanblades are plastic concepts for now. In a few weeks I will make the Fanblisc ;) Than I will upload a video.

[@ekingorgu]

Did you build it yet?

[@terryblankinship2192]

this guy desighns a axial flow turbine and it runs n seems to run well and its in its desighn infancy n no one gives him anything but critical pissing and whining, if no one ever took a chance and stood close to there own projects when there was a chance of failuire nothing would have ever been accomplished, there was zero viberation that could be seen and overaul it seemed very smooth and the turbine wheels were all made using spark erosion so some company that builds turbine wheels/blades obviously machined the rotating assembles so I'm gonna assume things where in order as for possiable failures and say it was just as safe s a jetcat powered bicycle lol or turbine jet, I don't run jetcat stuff because I like my wren and I jets black mamba better, also my bairds turbine which the owner of the ijets black mamba has helped me keep running lol,

[@ReggieRailSystems]

terry blankinship, I agree with you. And if it disintegrates while under power and he should survived Then without question he will learn a valuable lesson that nobody could ever instill in him. That’s life!

[@cowpens6]

beautiful sound!

[@YZ250W1]

Very nice work! Any idea what kind of thrust it is making?

[@olivierl6070]

Sorry to burst your bubble but that ain't the first. Jaguar made one decades ago

[@ckbne]

sorry to burst your bubble but Jag didn't. it was made by two brothers from the isle of man and jag was going to use it in their cars as a psu top up plant for hybrid. Great work on the engine mate, look very professional, you should be proud of it.

[@olivierl6070]

ckbne True, but my point is still valid.

[@YARCHLRL]

and is Jaguar a "model jet" because that is what the title says.

[@olivierl6070]

***** Well yours might be a greater achievement in the circumstances but it's not the first small scale axial flow engine

[@Osprey1994]

Love the sound of a jet engine.

[@superskullmaster]

Would it be possible to redesign the first stage compressor face to have a mounting stage for a gearbox connected to a fan. I think a 10 inch fan with wide chord blades running at a 1:10 ratio would almost triple the thrust.

[@jwholmes2]

It's really great workmanship. How about some data? Pressure ratio, airflow, thrust?

[@rafmanangleseygwynedd8026]

hi Paul, its amazing how much the sound sounds like a jet stood there, brilliant ,I thought it was going to take off, when the draw front started to move forward, now clamp it back onto your bike. ( again ) great video lol 👌🚀😃📷

[@ArcturanMegadonkey]

lol if you knew how much it cost to build......

[@SteamDougy]

if you have to ask...you can't afford it! ;)

[@gasturbine101]

Wow, a very nice piece of work! A credible looking design I would love to know more?

[@grahamj9101]

I went to a local model engineering exhibition last weekend, where the Gas Turbine Builders' Association had a stand. They were demonstrating one of their engines outdoors (between the showers). I spoke to the builder of his own-design axial flow engine, which was on display on the stand. At the moment, it is part-built and yet to run. It has a six-stage compressor (PR of 4:1) and the aerofoils are precision cast. On the subject of an intake bellmouth for the engine you show, it is obviously working well enough without it. Nevertheless, it's good practice and an axial compressor is likely to be more sensitive to flow separation than a centrifugal. A bellmouth would significantly reduce the likelihood of flow separation, give the compressor blades an easier ride and might even give a small, measurable increase in thrust.

[@waspsnest]

I dont know if James is ever going to try starting it. its well over 14 years since i went away from the GTBA (i was one of the founding members when it was called the GTBCG in 1990 ish) and it was almost complete then. I really dont think it will make any difference with a bellmouth, inlet velocity is now and the first stage rotor is 70mm from the existing inlet lip

[@grahamj9101]

He certainly didn't mention that it had been around that long! How low is the inlet velocity of your machine? You may well be right about the difference a bellmouth would/would not make: it might even encourage the development of the boundary layer, which wouldn't be good, but should be no worse than an airframe intake. My experience on the full-size things is that very small differences can sometimes be beneficial or detrimental, even within drawing tolerances. The first-stage blade profile of the Viper 632, the HP impeller L/E profile of the Gem, the minute differences in profile between GE and R-R manufactured blades/vanes for the Gnome - they all had a significant effect on performance and/or surge margin. Not to prove you/me wrong, but just to experiment, I'd be prepared to buy you a bit of round alum bar (say, 5in dia x 4in long), if you have the facilities to bore it out to the engine's intake diameter and produce a generous bellmouth radius.

[@waspsnest]

it might be worth looking at if only to settle the arguments. I would do it properly and rather than do an add on to the existing inlet ill replace the whole inlet duct with the bellmouth built in as part of the front bearing housing so there are no steps or joints to cause any air disturbance. i have the standard bellmouth curve calcs somewhere here, it would be the same as whats on the other engine that Paul put up on here the same time as this one. inlet absolute mach no is (theoretically) 0.45 at max rpm

[@waspsnest]

sorry forgot to say, inlet absolute mach no is (theoretically) 0.45 at max rpm

[@keithbrooks3406]

Thank you for this video.

[@ArcturanMegadonkey]

thanks for watching Keith

[@jolujo5842]

Ever measured the total lbs of thrust? I see you have it mounted on a linear bearing assembly. That makes me think you've been measuring output. Just curious. Cheers 😀

[@jaggar28]

Well done!!! How much thrust could it produce btw?

[@kevinbyrne4538]

BEAUTIFUL craftsmanship.

[@walkergarya]

When do they install the afterburner?

[@ricoreyes6044]

What kind of pressure ratio were you able to get out of the 4 stage compressor?

[@tommis1985]

Wow it even sounds like a real jet engine!

[@jazldazl9193]

?

[@joshmnky]

Did you manufacture the blades yourself? I had though spark erosion/EDMwould be a great approach for making small turbines. Did you stamp a whole side at once? Come in radially per blade?

[@coreyschmidt1647]

Need to build a RC F-15 to put that beautiful piece of machinery in.

[@garygranato9164]

great vid well done :)

[@creativityworld6781]

I really like it.. how much thrust generated? and please post some videos of your work steps

[@Flightstar]

my dream model jet is a high bypass fan powered by a axial turbine core with a decent compression ratio for optimized fuel efficiency.

[@jonolelaugerud8084]

How many kn of thrust is there in the engine running at max?

[@shortribs11]

How much thrust do you get at max power and how much does the engine weigh? One more question, how much fuel does it burn and what kind of fuel are you using?

[@peterstefan6900]

“Honey, have you seen the cat lately?”

[@spaziotempo72]

Hi....did you measured the boost? How many kgs gives? Thanks

[@lukaspfalz6128]

Would it be possible to see a breakdown for the engine? Knowing about how you designed and manufactured the parts could give a lot of us newbs insight to developing our own home-brews.

[@ArnoldsDesign]

It would cool to see the inner working elements of this engine. Did you burn the blades, or wire the geometries and tapers? Either way, fantastic use of a tool and die machine.

[@simondavid2519]

How much thrust do you get from that thing ?

[@BluesDoctor]

congratulations. look forward to watching as developments proceed.

[@VinEvgeni]

what is max thrust you got?

[@simontalbot-hurn9457]

That is on the superb side of awesomeness...!!!

[@marknewell7355]

That my friend sounded awesome a bit like a mini RR Olympus I've subscribed and liked anyway lol

[@ArcturanMegadonkey]

Thanks Mark.

[@bpresgrove]

Very nice work. I too was wondering when someone was going to build an axial. The more blades and stages I assume help with engine whine. What kind of output are you getting? There must be a marked improvement in thrust psi. Great job.

[@MekazaBitrusty]

I'm very impressed. 👍 I'd love to know how the profile of each blade is determined. I don't suppose you know of a link to their design?