Not a Spey, but usually they are ancient centrifugal compressor engines, and fairly rare, because it was finally re-discovered that (news flash): jet engines do produce a lot of heat, but their main purpose is to produce thrust, and that plays hell with the ballast on a railway...

@@AgentJayZ Thanks for the response. Wow, I've never heard of that type of engine before. Maybe if you're inclined you could tell us a little bit about them (centrifugal compressor engines) some time. P.S. Stay safe, making videos shouldn't require wearing a hero's hat and getting pummeled with rocks. We love you man! We want you to save Jay for another day!

Me too

Glad you didnt get smacked too hard by flying objects, and you has a protective clear filter on the camcorder!

And they were a half mile away.

I have a few videos of these engines creating their own snow storm...

You know when you are in a club... next to the speaker towers... you pants are vibrating against your shins, and you can't hear somebody, even if they yell in you ear? It's about a hundred times that loud. I actually was a DJ in a rock club in the 80s...

I have a video called full power in the rain.

It's ok to like the bigger, thirstier and younger sister.

I saw an F22 in Reno, and it could have been my vacation ears, but it seemed by much louder, snappier, and angrier sounding than I was expecting. Nice plane.

I still believe the Spirit to be the most body-intense sensation I've ever been to close too.. took off right over our heads and pulled up hard. (Taking off at military base. Not an air show) The ground was shaking and rocking. The sound was low and thundering. I don't think I've ever gone out of my way to overly express pride in America, but at that moment I felt like I had been saved and reborn by "the church of murica." Baptized in jet fumes.

That is a stupid question to ask here. Take physics course and get your own answer.

I'm not at all sure that I understand exactly what you are asking, but here is an edited cut and paste of what I posted about the convergent-divergent nozzle in a discussion in AgentJayZ's previous video. I'll start with the engine at maximum ‘dry’ thrust (military power in US terminology?). The nozzle is closed, with the ‘turkey feathers’ (we call them ‘’petals’ in the UK) forming a simple convergent final nozzle. For US readers, consider an F100 or an F110 engine and the appearance of the back end of an F-16. The difference between the outer and inner diameters of the closed nozzle is quite noticeable and there will be a rearwards load on it. This is as a result of the jet pipe pressure acting on the projected area (outer diameter minus inner diameter) of the nozzle. That's why, personally, I don't like the term 'propelling nozzle'. Now when the afterburner lights up and the nozzle opens up to become con-di, the engine conditions typically remain exactly the same, so its internal loads are obviously unchanged and the jet pipe pressure remains essentially the same. The physics state that the increase in thrust is as a result of the increase in velocity of the exhaust gas, courtesy of Newton’s Second Law, but what load changes actually occur in the final nozzle? Firstly, the outlet area of the nozzle is increased, so that there is less projected area of the convergent section for the jet pipe pressure to act upon and the rearward load on it is reduced. The gas velocity at the nozzle ‘throat’ is sonic (ie, at the local speed of sound). However, the speed of sound in the hot exhaust gas is much higher than the 760 miles/hr for the speed of sound in air that you might be thinking of. At 600degC, it's around 1,300 miles/hr, which is about the temperature of the turbine outlet, so it will be even higher downstream of the afterburner. The divergent section of the nozzle is still a nozzle (not a diffuser), because it is a supersonic nozzle, and there is a radical change in the physics and aerodynamics of a supersonic flow. The divergent section is, therefore, accelerating the hot gases even more and there is a forward load on the divergent section. The resultant increase in thrust, which is transmitted to the engine mountings via the jet pipe, is therefore produced as a result of a reduction in the rearward load on the nozzle and the creation of an additional forward load. Sorry, but I’m not in a position to put any actual numbers to these two loads, but, for example, the result is an increase in thrust from 11,905lb ‘dry’ to 17,835lb in afterburner for a J79-GE-17, according to Wikipedia.

Oh well, look, I understand what it its to study. But I like to participate in this channel. Jay himself often responds to comments, and I like that. I think he is a good teacher. I think that is one of the reasons he does this. If he chooses to respond I will get an opportunity to see it explained in a way that you may not get in a text book. That is why I ask. No need to get nasty. Sincerely Dr. Seth

grahamj9101 thanks for responding, I think that helps.

We are off grid at our test cell. We generate our own power. All the controls have UPS power. It has never failed. You never can say never, but so far... a 100% reliability.

'Garden blower" as in it moves the whole garden, not just the leaves on the lawn...

Use this to blow the snow from your driveway! ^^

When I was just out of school I got hired to write some fan balancing programs for GE Jet Engine Division in Ontario, California. I worked in the big jet engine test cell that handled turbofans. The little engine cells were wooden sheds about 12 feet high about 30 feet north of the big cell. I don't know what they tested there, but when they spun one of those babies up it was LOUD.

There are four separate sectors in each of the spray bars, fed by four separate fuel rails, visible on the outside of the engine. As fuel pressure to the AB increases, each of these four manifolds has a valve with an opening pressure, set at four increasing levels. The lowest valve opens, and the pressure continues to increase, until the next valve opens and then continues to increase... In this way there are four steps in the flame as each sector is energized, but since each sector is also progressive... to the pilot, it is a continuously variable amount of thrust augmentation.

Great explanation.

Lmao yes it must be done now.

The maximum speed of an F-104 was (according to Wikipedia) over 1,500 miles/hr. This means that the exhaust velocity in afterburner of a J79 would have to be a lot higher than this.

Yes! Nothing grows there.

In the aircraft engines it is replaced at every major overhaul (2,000 hours of use), at which time it appears completely unworn. In the industrial engines, it is inspected at each overhaul, and replaced when service limits of wear are evident. Bearings rarely fail; they begin to show wear, and are replaced when that wear exceeds the (very small) allowable amount.

@@AgentJayZ Thanks for the answer