Turbojet Tuesday

[@viscouscasual]

No sketchy ads, no clickbait, no brainrot. That's some high quality content here, sir. Very interesting to see machinery worth decades of human knowledge and efforts.

[@tomreid9326]

The sound must be amazing like you mentioned we have no idea exactly how loud it really is. Love how the guy was standing with earmuffs on with his hands pushing them , and then says to himself nope too loud, I'm out of here. Awesome video J

[@lerkzor]

Thank you for sharing this video. I could watch a great deal of fuel being consumed all day long!

[@CedarPass]

Loving the duct tape band-aid, my friend. Seems about right. Been there many times myself...cause it works!

[@wickedcabinboy]

@CedarPass - Came here for this comment and wasn't disappointed.

[@pibyte]

Thanks for the amazing footage. 90 gallons of fuel per minute is insane ... considering that the Starfighter had a 900 gallon base fuel capacity ... you not gonna fly with afterburner for long.

[@pibyte]

"Winter is coming. So get yourself an afterburner."

[@bobl78]

Sometimes I have an after burner when I had too much Chili

[@galponeroserial]

Your videos are amazing, thank you Jay. Greetings!

[@jeffmccrady9456]

Love the j-79!!! My dad was Navy!! He worked on the phantom, plus I lived by Boise Idaho!!! I saw heard the phantom j-79 daily! Totaly awesome!!! Love the channel.. been watching for a while 😁, keep up the good work!!!

[@balazsegressy3788]

The raw power of the J-79. 😊

[@kristyskirt9015]

OOH a J79 with afterburner to go into F 4 or F 104, Very smooth transition to afterburner, so if going into a F 104 Pier Carlo will really be happy with this fine overhaul and test by S&S Turbines. PS as always very good video and class by AgentjayZ.

[@rushd45]

Hi, I watch your channel from time to time, I'm just a normal guy, no connection with jet engines other than knowing they are in a lot of planes and find your explainations facinating. I recently came across the SR71 and its engine, the J58. Utterly extraordinary stories and explainations of the plane and its engine. The best so far was the description by James May when he landed...

[@AgentJayZ]

The only James May high altitude flight I know of was in the U-2. Where does he talk about the SR-71 ?

[@rushd45]

@@AgentJayZ Woops my mistake, you're right it was in a U-2.

[@ccserfas4629]

Good stuff again J, thanks!

[@jakebrodskype]

As a student intern many years ago, I recall an overhaul shop testing J79 engines. Those things were LOUD and when they lit the afterburners there was no refuge from the sound.

[@dennispolitic9491]

Powerful Jet Engine !!!

[@thehandlesticks66]

At least the bots are giving you exposure lol. In all seriousness, great video! I'm sure that power plant loved the cold dense air, even if we might not.

[@jimgoff1170]

I had heard a rumor that the smoke was from bearing oil that went into the jet stream by design! I’m glad I finally got the true story.

[@AgentJayZ]

I think pilots, and even ground crew... might enjoy having a bit of fun with those who aren't in the inner circle. I've heard some twisted things.

[@davidshutt2273]

Thanx, JZed

[@larryfischer2972]

I'll have to get one of those.

[@AgentJayZ]

We sell them

[@burlatsdemontaigne6147]

Very cool!

[@bobqzzi]

'Cuse me while I rip the sky

[@chartphred1]

The concept I can never grasp is that whenever you look at the back end of those engines pushing out ginormous volumes of hot air that all that air is being funneled through those tiny bloody holes in those shrouds, I find it staggering that much air can squeeze it's way through such tiny holes without tearing them apart?!

[@AgentJayZ]

The parts known as shrouds are solid, and have no holes in them. You must be thinking of some other parts. Even then, any air cooled parts take up a small fraction of the total airflow. If you are meaning the combustion liners, those are not tiny holes, there are a lot of them, and the air going through is compressed between 5 and 50 times it usual density, depending on which engine you are looking at

[@stearman]

That looks like a -17 engine. 17,900 lbs in AB. In 1986 those were $186,000 to the USAF.

[@AgentJayZ]

You sure? There's a data sheet out there for the -15 that says the price was 175,000 back in the 1960s. They are over a million to overhaul today.

[@dudiek12]

9:30 Wait, leaner (air to fuel ratio wise) flame burn hotter? Do I understand it correctly?

[@AgentJayZ]

I recently posted a video about fuel air ratio.

[@Kargoneth]

Such a horrifyingly-loud machine! I do not know how you can stand near it. You're far braver than me. I would be terrified that it might cause me injury. Perhaps it is confidence gained from personal experience and trust in your coworkers.

[@AgentJayZ]

Wearing earplugs under the ear defenders, it does not feel safe. Even with hands clamping over the ear defenders, it's scary. I have a whole playlist of J79 test vids. Many times I've tried to describe the noise level, mostly without success.

[@SirensAndAlarmsOfNorthernIL]

@@AgentJayZgotta be around 178dB or more from that close but below 185dB as 185dB is lethal. That is dangerously loud if you don’t have hearing protection

[@AgentJayZ]

I can't measure it, but my personal opinion is that it is dangerously loud. You instinctively hold the earmuffs, because you know that if they somehow get bumped and lose their seal... you ears are instantly destroyed.

[@cheeseburger3119]

I have a question about fasteners. What are those splined head bolts called?

[@AgentJayZ]

Most of the bolts you'll see on these engines designed after about 1955 are twelve point bolts and washers. There are indeed some that are spline headed. They look similar, but need a spline-drive socket or wrench to install or remove. The Rolls Royce Avon, and the Orenda engines were designed before the early 1950s, and they use six point, or hex head bolts and nuts.

[@robertw6894]

hi jay! how do you get a job working on aircraft engines like this? I'm currently attempting to get my A&P as I heard that's a good step into working with aircraft and their powerplants

[@AgentJayZ]

You heard that getting your A&P license is a good step towards working Aircraft and their Powerplants...? Now you need to convince me you are not a troll... ... ...

[@robertw6894]

@@AgentJayZ am I mistaken? im just trying to learn more about the job field lol, I've always had a passion for aircraft and engines and would like to be paid to work on them

[@AgentJayZ]

I would say for almost all employers, getting your A&P training is essential. You will learn and practice a huge amount.

[@robertw6894]

@@AgentJayZ awesome, thank you! love the content!

[@TheQuantumFire]

How are the carbon fiber blades tests going?

[@AgentJayZ]

Have not heard back from the designing engineers about the next step in their plan. When we do, I'll let you know.

[@SuperSecretSquirell]

You ever do any AB testing at night? Would be quite the sight.

[@AgentJayZ]

See response below.

[@SuperSecretSquirell]

@AgentJayZ ah dang. Understandable though. While working nights in Iraq, I got to watch two F18s do full AB takeoff and a near vertical climb right in front of our shop. It was glorious.

[@bobl78]

We Need more test runs again, have had more in the past.

[@AgentJayZ]

So... glass half empty? Sorry.

[@NeroontheGoon]

Full AB run on a J-79, what other type of run is there!

[@turboguy86]

Do these engines use catalytic ignition for afterburners?

[@AgentJayZ]

If you look at the video I made just before this one, I show the reheat ignition system. If you type in afterburner or ignition, or afterburner ignition... into the search feature on my channel page, there are more videos on that subject.

[@spud4839]

Nice engine

[@mattbucko6900]

How does the noozle knows when the afterburner is lite?

[@AgentJayZ]

The temperature in the jet pipe is measured, and used by the Nozzle Area Controller

[@C-M-E]

Quick question for you Mr Zulu; is the shop address still good to send a package? I found some goodies for you, and a special something that sound work a treat for attenuating mic levels for jet exhaust if you still plan to film them in the future.

[@AgentJayZ]

Everything is in the same place. If I move anything, I'll let everyone know.

[@C-M-E]

@@AgentJayZ Excellent. One part is ready to go, I'm working on the molds for the other.

[@jeffatto2738]

Could you do a night shot of AB stepping

[@AgentJayZ]

We have an agreement with the airport and our neighbors: No running after 5 pm. So it is possible, but highly unlikely. The test cell has a mission to test engines, and running in the dark is not one of the goals.

[@spud4839]

Oh damn that’s like a jet engine

[@davidvendt4579]

On an AB engine , I know the pilot controls the AB. Does the pilot also control the "turkey feathers" too. Or do they operate automatically in response to throttle position?

[@AgentJayZ]

The turkey feathers are controlled by the Nozzle Area Controller. It uses signals from the power lever angle, engine rpm, gas temperature and mechanical sensors measuring nozzle actuator position. It modulates the position of hydraulic actuators attached to the variable nozzle assembly, maximizing gas acceleration through the nozzle.

[@IzySly-g4h]

It's me again , a drahm is 1/8 of an ounce ,not a gram ,I'm sorry

[@gregebert5544]

What's happening on the EGT gauge as the afterburner is ramped up and down ? Or is the gauge upstream ??

[@AgentJayZ]

EGT is measured in the normal spot. Upstream of the AB. The afterburner is literally a ramjet engine whose inlet is the exhaust of a turbojet.

[@atifali2271]

Good information sir i am from Pakistan Karachi

[@RobertSchmitt-u7l]

After ceramic coating blades and stators, could or does industry chemically coat/deposit precious catalytic metals from a solution into the ceramic or on the ceramic surface to help combustion or lower emissions??? Seems like its just the cost of the metals, no drawbacks, only gains?

[@AgentJayZ]

Combustion is finished before the gas stream gets to the turbine section, if everything is functioning as it is designed. So, no gains.