I'm far from any aviation related industry but I already lost the count of videos from your channel I'm watching in a row. Every single video is a pleasure to watch for technology lovers. Thank you so much for sharing information with geeks all around the world!

I remember working on a small J69 (centrifugal) engine with an electric starter in the USAF. It brought back a lot of memories. Thanks.

I find it kind of amazing that we had the technology to design and build these things in the 40's and 50's.

Thanks for the explanation Jay. I work regularly at an FBO and am in and out of the MRO bays and had wondered why I never saw any large electric motors, especially after using a 48V starter off of an old military surplus jet engine to make an electric car in my later childhood. The powerplant mechanics all know how old I am after I tell them this story!

Very informative, as usual! In the 60s and after the Mirage fighters had their jet engine started by a turboshaft engine - which was electrically started - located in the intake as on the video. That turboshaft engine was a cute little engine of 60 hp at first and later 80 hp.

I’d love to see some specs on those electric starters sometime if you have them. It’d be really interesting to know the hp ratings, watts or amperage, etc.

I absolutely love your channel. Thank you!

Man you are really kind in your description, comments and conversation... , you really have people “be” there in the room with you.., they feel part of it👍 cheers!

It's just brilliant that these beasts were designed around 80 years ago.....that golden era of aerospace.....

Sounds like a different start sequence is being used by the sound of your description. Our huffer supplies compressed air to drive an air-turbine starter,, which mechanically turns the engine. There are turbine-impingement starteing systems, in which compressed air is directed at the turbine and so it does the actual turning of the engine.

Compared to the J47 this engine is surprisingly clean at the front. You have two hydraulic pumps and primary fuel system there. The secondary one was on the left side of the engine. You could work in it from inside the intake duct but it was a pain. The J47 is also a tight fit and you have nothing to guide it. Also the tail and the fuselage had to be well aligned in order to assemble it back. We used a jack in the nose to do that. Also, the jack aleviated the load on the nose wheel since the CG travelled well forward with the tail out; it was realy heavy. The Fiat G-91 tail was much lighter but even so we still used the jack; it helped a lot and spared the nose wheel.

Thank You JayZ, enjoy all you are presenting sir.

I performed maintenance on the MD-3 motor generator ground power dc motor generator. The critical component was the spring loaded actuators that "rubbed" against the rotating exciter. The unit had a high powered gas non turbine piston Packard engine that would sing songs at low rpm to high rpm of what normal human hearing would want to push the volume up toward deafness levels. When the cowl was rotated for engine inspection and the full force of the motor could be observed. THE BLUE flames crackling UPWARD in hard attitude could not be ignored. -- Memories of a former AGE mechanic

Amazed to even see this being used now! Big electric motors weigh a ton. Surprised to even see one in use anymore. I worked at Garret Air Research/Allied Signal quite a bit, please don't kill me, so I have seen a lot of this stuff. Honeywell now owns the facility. I have not been back there since they took over.

Well, your thinking is bang on... because although I focus on the starter role... this is actually a starter generator, and it does axactly what you say.

Today first time I got clear concept about starting jet engine

In this application, as in most of aviation, a lockwasher is not used. Imstead we have a flat washer, and a self-locking nut. The self-locking nut is described in my Lockwire video.

@Blackmoonempire Yes, they are fixed with tiny allen screws. It seems easier and more secure to use studs, but that's the way it was done.

Wow! Okay, more learning I've got to do. Thank you for the information and leads!

There is a video out there of a Canberra bomber having one of its Avon engines spun up with an AVPIN starter. They don't start the engine, but it is amazing how quickly that cartridge starter winds up the Avon. You can find it.

Some very fascinating fundamentals I wouldn't have even known to ask about - THANKS!! Jim/Ohio

i'm glad youtube recommended this to me

Really cool - that electric starter motor is really a monster. Thx for showing and explaining :-)

@Blackmoonempire ... you're right. I don't watch my vids very often, but I just looked at this one again, and those bolts are indeed retained by roll pins. Good eye !

Turbine engines use high voltage discharge ignitors to supply spark to get the fuel burning. Once the engine is running, these are usually switched off. Like a candle or a gas lantern, the engine will burn fuel as long as it is available. Engines only stop when the fuel is cut off, with extremely rare exceptions. Re-starting while in flight can be done, as long as the core is turning at sufficient rpm.

It's been a long ass day, and coming home to a new AgentJayZ video really made it all worth getting through! That's a sexy engine btw. I hope to see a test video before you guys ship it back to the owner!

It's actually a very small amount of material. It does not provide the actual energy for the spark, but is incorporated into an electronic component that produces a variable signal. This signal is used to trigger an excitation circuit ( whatever that is ), producing small pulses of current, which are amplified to huge levels by more circuitry, until we have the huge and dangerous spark that is present at the ignitor plug. Any liquid that burns can be used as fuel.

Actually Electric starters are coming back and are in use. 787 electric starts for example. And with big Lithium on board batteries some aircraft use those to directly spin the starters without the need for an APU go supply initial electric And once the engine is started the starters are driven by the engine and become the generators. So no more dead weight.

I love your videos and I'm glad you share this stuff with the rest of us. I work on computers and other electronics the way you work on these amazing engines and my friends are always amazed by it. I wonder if that's the same amazement I feel watching you rebuilt this stuff. Lol. Thanks for being amazing.

Your explanation of duty cycle would explain why my electric starter motor didn't work well as a drive motor for an electric car :D

Thanks Jay! Very informative as usual! Rich.

@krbruner In a power generating plant, the electric or electric-hydraulic starter is most often used, because as you say it does make sense. In natural gas pipeline compressor staions, often an air turbine starter is used, and it can use the pressurized natural gas in the pipeline as its power source.

Thank you Jay! The kindest person as always! :o))))

BEST CHANNEL ON KZfaq!

@dtiydr The fuel pumps, oil pumps and tach are attached. It takes some power to turn them.

Good to watch

Hi Jay ! Im a fan from Germany. I found your channel some month ago. Im a fan of turbines and you got the right channel where i can expand my technical horizon. I hope you understand what i try to say. Keep on the good and very interesting work... ! =)

First off, Thank You, Thank You, Thank You! I have throughly been enjoying your videos! They're GREAT! Back in 2003 I got to see a 1964-ish Saab Draken fly powered with a Volvo RM 6C Flygmotor (a.k.a., a Rolls-Royce Avon). The start sequence amazes me; it sounds like a huffer, then an electric motor, then compressed air, followed by a vacuum cleaner (the engine). You gotta' love it! Is the compressed air helping turn over the engine too? Thanks again for all your efforts!

Yes, two in fact. this very engine is featured in " Orenda Type 14: A Canadian Turbojet (1) " and also in " Orenda 14 in the Sabre6 "

@FrontSideBus Yes

We do that in the test cell. It's just down the street. Lots of engine test videos I've posted...

Many thanks for all of your efforts. So interesting

Hi Mr AgentJayZ. First of all I want to thank you for your amazing videos! I am studying a Bachelor of Aviation while I work on my CPL. It's such a pleasure to listen to a someone explain something they are clearly passionate about. My question is this: Everything I have read suggests that a pneumatic starting system is not only substantially lighter than an electric system, it is also cheaper, simpler and easier to maintain/repair. So why would you ever have an electric starter over a pneumatic on any aircraft? What is the advantage?

I don't know all the facts about all the engines out there. I only know about engines we work on. But it seems to me your observations are good. The smaller engines are easily started with on-board batteries. The air-turbine starter was developed for the larger engines. And I think only the larger aircraft use APUs. I am not an aircraft expert, though.

This just blew my mind. I always thought the engines in airliners were started electrically.

@saxonlight Hmmm... how about: Future tense: blind to consequences Present tense: unintentional masochist Past tense: digital amputee It looks like a "fan" but weighs nearly half a ton, and those blades are solid stainless steel...they'd chop up a broom handle like it was a french fry.

@pym480 If you take a look at one of my earliest videos, called "vintage fighter jet engine", it shows one of these ( Orenda 14 ) being started with the exact same type of electric starter. It was for a Canadair Sabre 6... the same type of plane this one is going into. That's Big Al running the electric start cart, and Electron Bill giving the signals. Robin is in the control room running the entire show. As usual, I was behind the camera loving every second, because I love jets !

monopropellant. The AVPIN starter is essentially a small and compact gas turbine, usually mounted in the nose cone of the engine, which is powered by Isopropyl-nitrate and air carefully fed and metered. It develops a very high torque which can crank and start the engine in just a few seconds. That would explain exactly the sequence of sounds. I have found evidence of usage of the AVPIN starter with the versions of the Avon installed in the English Electric Canberra. Hope this helps... :o)

@86Ivar Almost all modern airliners have an onboard APU to supply electrical power for the aircraft and a source of compressed air for starting the engines. These APUs are small turbine engines, similar to that found in our start cart. They are rated about 100 Hp. Give or take.

Here is a link to a video where a Bell 206 Jet Ranger starts it's turbine engine. You can hear the electric starter turn over the turbine, the igniter sparking and then the introduction of fuel. Best video I know of for the sound of a turbine starting. Very Cool Turbine Start - Bell 206 Jet Ranger Startup

yes, most airliners have an on-board APU that can start its engines and run all electrical equipment when the engines are not running.

The boeing 787 has electric starters for the engines. Since they've done away with bleed air to 'improve economy' (jury's still out on that one) they have had to incorporate 2 very large (250kVA) starter/generators on each engine and the APU.

I used to work for an electric starters company. To tell the truth I never thought there was any other way to start them, since they also produce the onboard energy. But the sizes are rapidly decreasing, a Rafale starter is like one third the size of that one.

It is actually not right that all modern engines are using compressed air for start up. Very modern engines like the GeNX-1B and the Trent-1000 are using so called variable frequency starter generators (VFSG) to save weight by getting rid of an external generator. These motors have the ability to work as a generator when they are not used as a starter anymore.

I do confirm and quote everything Jay wrote. The radioactive material was only present in very VERY small quantity (like a "dopant"), in a component called "spark gap". It was a trigger switch connected in the discharge circuit. In the laboratory where I used to work, we designed, built and maintained High Energy Ignition Units for turbine engines, but there wasn't any safety requirement for radioactivity, and that tells you that the amount of radiation produced should have been really low.. ;o)

Yes they are. And many large modern engines also have electric starters.

Very interesting. Thanks!

love your videos man, keep em coming

Thanks. Great video.

We don't work on engines that go into helicopters, but if it's a retired engine out of a helicopter, going into a fast boat or a jet-powered mud bogger, then yes, we do work on those.

for me is 2 thank 4 you all appl coming with technology thank alot

haha. excellent! thanks for the reply!!!

Some newer jets such as the 787 have gone back to using an electric starter generator since advances in technology have made large electric motors, and their associated equipment much lighter.

Since the subject was mentioned in an earlier video. I think we are going to have to come up with a technical term for someone wanting to put their fingers into the spinning blades (during the first 30-40 seconds of this video). I know it is stupid but I admit it I had the urge. =D

One of the early German jet engines had a motor from a motor cycle as a starter, It was a pull start :

@86Ivar They can, the engines use the force of the wind being to spin the blades, then the engines can reignite.

very informative videos.

I think I mention all the time it's out of a Canadair Sabre 6.

@MisterChips Electric motors have improved a lot in the last couple decades with rare-earth magnets, so the new starters should be lighter.

@colin340 Have you watched the air starter videos?

You're welcome! :o) My previous job was all about cranking, ignition and electrical power on aviation turbine engines... it was my thing! :o))))))))

Nice video! May I ask, where exactly can I learn more about electric starters on the web? It would be nice if it's as comprehensive as the video "The Air Starter - Turbine Engines: A Closer Look"

When an electric starter is turned on, does a shaft come out which rotates the turbine, then once the turbine is running and the starter turned off, the shaft disengages from the turbine, or does the starter continue to spin all the time the engine is moving but only have power to it when it is turned on?

@zero00tolerance To see air turbine starters, have a look at my videos on air turbine starters, posted a month or two ago.

Thank you!

Nice Job

I can definitely understand the weight savings benefit on an aircraft engine, but what about in an industrial application, where weight savings are moot? Would seem like that in an industrial application, rolling around a huffer, would kill the plants ability to control stuff automatically. If the turbines are in a power generation plant, wouldn't electric starters just make more sense or do some plants use a large electric industrial compressor to start the turbines, instead of a huffer?

Jay, another great video!!! It blows my mind how complex and sophisticated the jet engines were when compared to the technology used in the auto industry. Chrysler's turbine car of 1963 was a neat concept. Do you have any opinion on that product?

ORENDA! British & Canadian engineering at AVRO Canada in Malton .(Now Pearson international - Toronto)

I can say I have started a couple of airplanes with electric motors it's exciting and very dangerous position to be in.

@AgentJayZ Yes ofcourse, i totally forgot about those things.

I was dong some research on bearings and I came across a video Radial Air Bearings on a Precision Shaft, Do you think air bearing could be apply to jet engines?

I would like to work on that kind of thing !!

Yes, small jet engines such as those in small turbine-powered airplanes and helicopters use electic starters.

When at the airport, i never see some compressors etc starting the commercial airplanes, do they have electric starters driven from batteries or the APU?

I've helped hang several F-4 engines. It really sucks to spend 2 whole shifts hanging an engine and then something is wrong and it has to come back out.

Your description of the startup sequence of sounds for the Saab Draken puzzled me quite a bit... I went through a few videos on YT, and definitely that's NOT an electric starter motor. By putting together pieces of information here and there (many from a very fine book written by nothing less than Rolls-Royce), it seem that the version of the Avon whick powered the Draken used what's called a "Combustion starter", or "Isopropyl-nitrate starter". Isopropyl-nitrate (a.k.a. AVPIN in aviation) is a

Great videos. Thanks for the tutorial on safety wire. Can I come work for you?

Terbaik lah Tuan.

Interesting how the bolts for the starter are fixed, it looks like they are fixed with a kind of splint pin. Is there a thread in the engine frame, or are the bolts only fixed with the pins? I saw that at around 3:35

hmmm, I never realized that airliner engines where all started with a starter cart :O:S

Nice vid as always. Does that starter double as the genny? I think some models of PT6 engines use them as starter-generators.

Would love to se you start that engine!

NICE

Thank you sir, but I want to your boy on that works I want to learn it

thanks a lot !!!!

Im really suprised it slowed down that fast, i expected it to spin for maybe some minute before stop, is this normal?

@operationrepo007 maybe... yes...yes... no.

Is it not possible to controlled spray a high pressure mixture into the combustion chamber, and thereby start the engine by its own drive mechanism?

Are all airliners dependent on ground support to start? Can't the APU be used to start the main engines somehow?