What's With Annular Radiators?

[sideshowbob9]

Only if putting one on a MiG-3 is silly. Or a P-40. Or a Beaufighter. Or a ......

[The Wooksta!]

I did consider using Merlin 85's on a developed Beaufighter years back but they were too big.

[Geoff]

The early Ki-43's had annular rads as well.

[rickshaw]

The early Ki-43's had annular rads as well.

Weren't they radial engined?

[jcf]

The early Ki-43's had annular rads as well.

Weren't they radial engined?

Yep, but the Ki 43 1 used an annular oil cooler mounted to the front of the engine.

[rickshaw]

This heavy-bomber (maybe more accurately a VERY heavy dive-bomber!) had the "coupled" DB-606/610 liquid-cooled engines in a large, circular housing, and had annular radiators. The He-177 was indeed an "operational aircraft" but largely unsuccessful, largely as a result of engine overheating and fires (so maybe the annular radiator wasn't such a good thing here!).

Its failure was caused primarily by the machine being rushed into production before a cooling fault was found.  It ultimate problem turned out that the engine bearers were too short and too rigid.  However the oil pump also turned out to be insufficiently powerful and oil ended up foaming in the system, so that the engine overheated. The engine bearers added to that by causing too much vibration that eventually the oil and coolant pipes would fracture and spray oil on the hot crankcase and a fire would result. Ernst Heinkel identified the problem but the AMT prevented him from stopping production just as it was getting under way to fix it so the aircraft was fatally flawed from the start.  Not really his fault though.  He wanted to fix it but was stopped by the "needs of the war effort" and the short-sightedness of the Luftwaffe in not acquiring a heavy bomber before war broke out.  So they compounded the error with even more short-sightedness.

[sideshowbob9]

On a not completely unrelated note, my admittedly rough calculations make the Jumo 211s off of a Ta-154 to be almost perfect (within 0.5mm in 1/72 scale - close enough for me to fudge it) for a R-2060 Yellowjacket, which was an unsuccessful liquid-cooled radial (5 cylinders per row, 4 rows). Had it been given a gestation period similar to the V-1710, it may have seen more success.

Given it's radial nature, it's certainly reasonable to postulate it using an annular radiator.

I'm planning on putting one on an A-17 as a test hack and maybe a couple of developed versions (Jumo 213s) on a F-82.

[rickshaw]

I think it was more to do with having a common nacelle which either a radial or the inline plus annular radiator could be attached to with minimal hassle.  IIRC, they appeared at about the same time that things had turned against Germany and they were having to streamline production as much as possible.

The "power egg" concept really took off as things got bad for Germany in 1944.  One of its advantages was in the repair organisation.  They could just replace a damaged engine with what ever was available.  Its other advantage was that by grouping everything on the engine, if something went wrong with the cooling system, you just pulled the whole engine and repaired it at greater leisure after you'd replaced it.  Finally, by grouping all engine systems closely together you saved on strategic materials for things like hoses, reduced likelihood of battle damage (smaller target to hit) but at the expense of aerodynamic efficiency.  Speer and his crew reckoned that was OK.

[dumaniac]

yes Heinkel built one (I think) He 277 - a He 177 with 4 nacelles instead of two nacelles - and it was faster.  But by then the die was cast by Goering and he would not listen to Heinkel.   I built that conversion a few years ago.

And there was one annular radiator version of the He111 - its on my to-do list.

[sideshowbob9]

And there was one annular radiator version of the He111 - its on my to-do list.

He-111V-32 wasn't it? I would love to see that in plastic.

[sequoiaranger]

>And there was one annular radiator version of the He111 - its on my to-do list.<

Hey! Wouldn't it be fun to buy a Ju-88 and He-111 and just switch cowlings? The He-111 would then be "annular" and the Ju-88 would be "regular".

Eye candy (flavored with vinegar?).

[Geoff]

.............Eye candy (flavored with vinegar?).

Oh I like that!! ;-)

[sideshowbob9]

A glimpse of an annular Sabre Warwick here: http://www.flightglobal.com/pdfarchive/view/1961/1961%20-%200749.html

(bottom of page)