I'm lucky enough to live somewhat close to the museum and those planes are fucking huge

Thats how my wife does it too!

That’s how Kent State teaches its aeronautical students as well 😂

It's a simple way to remember when applied nightly S-S-B-B in a college environment & relate 4 stroke theory .

XD

Inverted engines, of which many thousands were made prior to and during WWII, had oil control issues to overcome for all cylinders, not just the lower cylinders as on radial engines. Radial engines, mostly in the form of rotary engines with the engine spinning around a fixed crankshaft, were common and extremely successful during WWI, so they are hardly "weird." All piston engines have the potential for balance problems with rotating and reciprocating parts, but the radial configuration is no worse than any other. And the myth of unequal piston wear due to orientation relative to gravity is just that. The moving parts of internal combustion engines are subjected to acceleration forces of such magnitude that the force of gravity is not even a rounding error in design.

Radials are "dry sump" meaning they have no oil pan. They instead have an oil tank, normally mounted on the firewall. There are pubs, likely on line which explains how the system works. Combination of pressure feed and spraying/slinging oil onto various components.

There is a very small collection sump and a scavenging pump to remove excess oil back to the reservoir tank, oil is pressure fed from the reservoir tank to the engine by another pump. Note that the cold start process for a radial always involves turning the motor slowly through 3-4 revolutions before attempting to start, this is because after sitting for some hours oil(and sometimes fuel or moisture) can settle in the downward angled cylinders seeping passed the piston rings into the combustion chamber and at the extreme cause a hydraulic lockup or more commonly it reduces chamber volume drastically increasing compression ratio and/or causing a hydraulic hammer(kind of like a garden hose with bubbles in it will splurt and pop and shake when you first turn the water on)

I wonder how they can fit 5 connecting rods to one lobe/throw on the crank, the would need to be really fine/thin in comparison to a car engine.... Am I missing something?

@@homewordbound4970 I see it has been some time and no one has answered. There is one rod in each bank called the master rod. The other articulated rods are pinned to the master rod at the circumference of the rod crank end. His video shows the motion but it is not explained. The explanation gets quite complicated after that. This system causes timing and stroke length errors that must be compensated for. Most engines have a compensated breaker cam in the magneto. The real part to understand is the cam ring. By a 4 lobe cam ring I mean four intake and four exhaust lobes. A nine cylinder can run with a 4 lobe cam at 1/8 engine speed in reverse rotation to engine rotation. It can also run with a 5 lobe cam ring at 1/10th engine speed in the same direction as engine rotation. If you want to draw it up start with a 3 cylinder. A single lobe will turn in reverse at half speed and a two lobe at quarter speed. If you take the time to understand the cam ring geometry you will also understand why there is an odd number of cylinders in a bank and the firing order is odd then even.

Not always. Maybe nowadays.

I've only seen a photos of a radial engine/on tv, it looks like the barrels/cylinders are arranged inline/level, I'm wondering how they managed to fit 5 connecting rods/big end bearings to the crank? I can only picture room for one unless the cylinders are slightly off? I've often wondered when I see them on TV, I'm a bit mechanically minded but I can't get my head around that? I'm watching Valkyrie and seen a radial so here I am trying to find out, I get the 4 stroke just can't picture the big end bearings arrangement for multiple pistons 🤔

@@homewordbound4970 Master & slave rods.

@@heinzhaupthaar5590 Thanks very much I'll look into this 👍

@@homewordbound4970 The most common arrangement is a master rod/articulated rod arrangement. The crankshaft throw (in each row, for a multi-row engine) rotates a connecting rod with a piston on the other end as usual. This is the master rod. This rod has extended flanges with multiple holes drilled into them in a circular pattern, one hole for each of the other cylinders. Each hole has a pin in it. Each pin is inserted through the "big end" of a straight connecting rod which is retained between the two flanges of the master rod. The other end of each "articulated" rod, as they are known, is a "little end" through which the piston pin is inserted, so each articulated rod also drives one piston in its respective cylinder. Each articulated rod is free to rotate side-to-side enough to keep pointing at its cylinder as the crankshaft throw moves the entire master rod, and its captive pins for the articulated rods, in a circle. So, in a nine-cylinder engine, or row, you have one piston being moved directly by the master rod, and eight more pistons connected to the periphery of the master rod by articulated rods and moving them as the master rod circles the crankcase. There are complications in this arrangement due to the fact that the articulated rods do not move on the exact circumference of the circle described by the crankshaft throw, but these geometrical characteristics can be compensated satisfactorily.

RCmies "class crash"

You must immediately retreat to your safe place, drink some hot cocoa and pet your comfort puppy.

Very intense isn't it 🤣

😶‍🌫️

On the specifications of the 28 cyl engine, it says 3,500HP

V14

maybe about 1600 hours power

That one deals around 4200 hp, hello from 4 years in the future btw

Not that I have any credentials or actual knowledge, but I would assume efficiency is similar to that of "regular" piston engines like what you'd find in most cars

Their main benefit is that air cooling works really well for them, so you don't need a radiator. Also, they can usually still run even if one or two cylinders get shot off. Important for a warplane.

Initially yes, very much so. That's why radials were more common in WWI. Between the wars, advancements in liquid cooling made inline engines slightly more efficient for aircraft use, thus the introduction of Merlins and Allisons and what not. But then NACA and others did some serious research on things like cowl designs that reduced drag on radial installations enough to get them back up to inline levels of efficiency. Thus giving us P47s, Corsairs, FW-190s, etc.

@Samuel Prince oh, now I understand. Thanks a lot I’ve been trying to figure this out

kzfaq.info/get/bejne/ma9yirGmnsytoqM.html

@@tracersedge Thank you!

Britain used many thousands of radial engines during the war. The Bristol sleeve-valve radials were quite successful on bombers, transports, and especially on the famous Beaufighter.

@@Hopeless_and_Forlorn Yep. They also used a lot of radial powered American aircraft like the P47. In fact, many British airmen that got "upgraded" to P51s wanted their P47s back.

@@Hopeless_and_Forlorn I stand corrected..

Cooling. The air must be forced through the cooling fins of the cylinders. This is done by the design of the pressure-cowl, the engine enclosure.

Radial engines require an odd number of pistons

Millions. Nearly every Harley Davidson in fact. But they are not radials

Simply: it’s not small. Complexly: the propellor is shaped perfectly, and spins so quickly that it pushes air behind the plane. Sir Isaac Newton tells us that every force has an equal and opposite reaction, so this pushes the plane forwards, and the wing is shaped so that the air flows over with a higher pressure on the bottom of the wing- this is called lift. When the engines make the plane fast enough, the air can flow fast enough creating a big enough difference in pressure for the aircraft to take off!

@@apexjailor9349 had no idea that not so “small” propeller is that powerful. Thanks mate.

The fuck you mean? Wankel (rotary), regular piston engines and radial engines can all work in 4 strokes. I think you meant the difference between a standard piston engine and a radial engine.

Dibya Jyoti there is a piece in the axis, just like an Otto engine, i don't know It's name in english

Dibya Jyoti Well the pistons together essentially draw a circle. So you need a piece that's the length of the radius of the circle which the axis attaches to in order to have the axis in the middle. Not sure if that was your question though.

This is not a rotary engine. This is a radial engine. They are distinctly different.

No. The inertia of the propeller is enough. They do need crankshaft counterweights to dampen various orders of vibration.

@srihari vaila, this should answer your question: kzfaq.info/get/bejne/p9CehK6Js7bXm2g.html

DC3, C-47 used a PW R-1839 Twin wasp 2 rows of 7

Try this video, it explains how the engine works instead of just a lesson on four-stroke engine operation: kzfaq.info/get/bejne/p9CehK6Js7bXm2g.html

He’s dead inside.

...Then you suck at life.

Did you know a lot because why are you watching this video if you know a lot?