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General Forums => Aces High General Discussion => Topic started by: SectorNine50 on September 14, 2008, 07:18:12 PM

Title: Radial vs. V Engines
Post by: SectorNine50 on September 14, 2008, 07:18:12 PM
I was wondering if anyone know the pro's and con's between radial and V design engines.  I understood that radial engines tend to be more durable, and V-engines tended to be more fuel efficient.  Are these the only differences?

Also, what would be the appropriate title for the "V engines...?"  lol
Title: Re: Radial vs. V Engines
Post by: Motherland on September 14, 2008, 07:26:14 PM
Also, what would be the appropriate title for the "V engines...?"  lol
Inline.

The two main advantages of radials, that I'm aware of, are durability, and the fact that they are air cooled. The first is self explanatory... for the latter, instead of having radiators and all the ducting that goes with them, which add weight and can be damaged, radials cool themselves mainly with their open 'face' I guess you could call it.

The biggest advantage of inlines that I'm aware of is aerodynamics. That and you can run a cannon through it (dunno if it would be possible with a radial but I've never seen it done).


I know I haven't hit on all the pro's and con's... but that's as far as I know. (or at least I think I know... :noid )
Title: Re: Radial vs. V Engines
Post by: SectorNine50 on September 14, 2008, 07:28:51 PM
Inline... Duh... :rolleyes:

I knew that... lol
Title: Re: Radial vs. V Engines
Post by: bj229r on September 14, 2008, 07:42:14 PM
oil leaks vs coolant leaks....oil lasts longer
Title: Re: Radial vs. V Engines
Post by: Ponyace on September 14, 2008, 08:05:31 PM
The advantages for inline are:
-streamlined shape
-easier to handle due to less torque

The cons:
-fewer horsepower than the radial
-easily damaged

The advantages for radial are:
-more horsepower
-very durable

The cons are:
-little harder to control due to the high torque
-less streamlined then the inline

But there are exceptions to this, such as the high power of the Sabre inline engine on the typhoon/tempest, or the low power of the Zeke's sakae radial engine

Basicly, its been an arguement for years which one was better, and pretty intresting which contry pick which.
Japanese=mainly radial (D4Y and Ki-61 are exceptions)
British=mainly inline
U.S.A.A.F.=mix of inline and radial, but only radials for bombers
U.S.N.=mainly radial
German=mixed
Russia=mixed

Hope this helps. :aok
Title: Re: Radial vs. V Engines
Post by: Anaxogoras on September 14, 2008, 08:14:05 PM
Don't forget that radials were far easier to service because of the accessibility of their components.
Title: Re: Radial vs. V Engines
Post by: HB555 on September 14, 2008, 10:26:34 PM
Reno Championship Air Races just wrapped up today.
Two P-51's (inline) held together and won the Gold. Strega and Dago Red. Design and weight beat the horsepower of the radials. This time.
Full result and lots of great pictures in the web site.

http://www.airrace.org/indexJS.php

Title: Re: Radial vs. V Engines
Post by: CAP1 on September 15, 2008, 01:05:49 AM
I was wondering if anyone know the pro's and con's between radial and V design engines.  I understood that radial engines tend to be more durable, and V-engines tended to be more fuel efficient.  Are these the only differences?

Also, what would be the appropriate title for the "V engines...?"  lol

radial engines are air cooled. much more rugged, and harder to damage in combat. good for long distance flights back then.

v engines require cooling systems, which can become quite complicated. more systems to damage. they allow for a more aerodynamic shape to the aircraft.

 in the long run, i think one is just as good as the other, as long as they're used in the right way
 :aok
Title: Re: Radial vs. V Engines
Post by: SD67 on September 15, 2008, 02:31:12 AM
The Napier Sabre engine as used in our Tempest was actually a horizontally opposed H pattern engine, it was notoriously unreliable but unbelievably powerful.
These images from the Hawker Tempest Page. http://www.hawkertempest.se/engines.htm
(http://i12.photobucket.com/albums/a217/sarahjeanb/Peters/pietsabre-5.jpg)
(http://i12.photobucket.com/albums/a217/sarahjeanb/Peters/sabre3.gif)
Title: Re: Radial vs. V Engines
Post by: SectorNine50 on September 15, 2008, 04:31:55 AM
Did I read that correctly?  The Tempest has a Diesel engine?!

Quote
Design was initiated in 1935 based on an earlier study for a compression ignition diesel. British Air Ministry Initial Acceptance test were completed on 17 January 1938 rated at 1350 hp. This figure rose to 2050 hp by March. By June 1940 it had passed its Air Ministry 100-h type test on its first attempt at 2200 hp and 3700 rpm, making it the world īs first 2000 hp production engine.
By 31 May 1939 the Sabre was ready for its first flight in a Fairey Battle at RAF Station Northolt.

Which Tempest engine do we have in AH?

The VII series had 3055HP... And developed almost 4000HP in a test!!! :confused:
Title: Re: Radial vs. V Engines
Post by: SD67 on September 15, 2008, 04:46:38 AM
It runs on gas :aok
Title: Re: Radial vs. V Engines
Post by: Krusty on September 15, 2008, 10:19:59 AM
I think of the temp engine as a X design instead of an H or V shape.

The heads may be flat, but the rods on the pistons angle in at a "X" cross shape, I think
Title: Re: Radial vs. V Engines
Post by: Chalenge on September 15, 2008, 10:25:10 AM
It was also so unreliable that it should be removed from the game.
Title: Re: Radial vs. V Engines
Post by: Hazzer on September 15, 2008, 11:17:11 AM
 The X design was called the Vulture,and was  tested on the early Typhoon prototypes,the Vulture powered model having the name Tornado.This Engine was Unreliable,so much so that the Avro Manchester - the only design powered by the Vuture in service -lost more Aeroplanes to engine failure than to enemy action.

 I believe the Vulture was comprised of two RR Peregrines,welded together into the X form.

 The Avro Manchester became the highly successful Lancaster,when fitted with four RR Merlins.

 The RR Peregrine was the final development of the successful RR Kestrel,the Westland Whirlwind was it's sole user. 
Title: Re: Radial vs. V Engines
Post by: 2bighorn on September 15, 2008, 11:25:11 AM
The heads may be flat, but the rods on the pistons angle in at a "X" cross shape, I think

They don't. Sabre is a true H-type (2 x flat) with two crankshafts. RR Vulture (2 x V) would be an example of X configuration.

Title: Re: Radial vs. V Engines
Post by: Krusty on September 15, 2008, 11:27:21 AM
2 crankshafts? Seems kinda redundant, overly complicated, and I can see why it was unreliable.

Heck, even today we're still having gearbox problems on 2 powerplants sharing the same shaft (the Osprey development comes to mind)
Title: Re: Radial vs. V Engines
Post by: Hazzer on September 15, 2008, 11:31:24 AM
 The problems with the Napier Sabre were gradually ironed out in service with the Typhoon.

 The Typhoon suffered not only engine failures,but structural failures mainly due to tail flutter,this continued even after tail strengthening,although to a lesser extent,as did carbon monoxide leaking into the cockpit from the Engine bay a problem the much improved Tempest shared.

 Not using the oxygen mask at any altitude in either model could be - and on more than one occasion was -  fatal.
Title: Re: Radial vs. V Engines
Post by: BaldEagl on September 15, 2008, 11:41:55 AM
Basicly, its been an arguement for years which one was better, and pretty intresting which contry pick which.
Japanese=mainly radial (D4Y and Ki-61 are exceptions)
British=mainly inline
U.S.A.A.F.=mix of inline and radial, but only radials for bombers
U.S.N.=mainly radial
German=mixed
Russia=mixed

I just watched a video I have at home a week or two ago about the FW190.  The only reason they used radials in the 190's was because all the in-line production was committed to the 109 series.  It wasn't by choice. 

In fact, Kurt Tank tried to streamline the cowl by elongating it and reducing the radius toward the front but it restricted airflow to the engine too much and was removed.

It turns out the extra HP from the radial more than compensated for it's lack of streamlining.

I suspect available manufacturers and production capability played a role in many of these choices moreso than design choice, although use of radials by the USN was definately design choice.
Title: Re: Radial vs. V Engines
Post by: 2bighorn on September 15, 2008, 12:03:59 PM
2 crankshafts? Seems kinda redundant, overly complicated, and I can see why it was unreliable.

Reliability problems were mainly due to production rather than design. Whilst the H design is more complicated than V configuration, it was the only way (at that time) to get that kind of volumetric efficiency and keep the size compact enough for fighter plane use.
Title: Re: Radial vs. V Engines
Post by: Saxman on September 15, 2008, 12:19:30 PM
Pony,

Severity of engine torque wasn't dependent on the engine configuration. A high-powered inline engine could put out just as much torque as an equivalent radial. The difference is that radial engines typically put out higher horsepower to begin with.
Title: Re: Radial vs. V Engines
Post by: 2bighorn on September 15, 2008, 12:38:56 PM
The difference is that radial engines typically put out higher horsepower to begin with.

That was true up to early '30s and only for power/weight ratio.

The main advantage of radials was simplicity which almost always translated into reliability.
Title: Re: Radial vs. V Engines
Post by: Krusty on September 15, 2008, 12:42:31 PM
The most powerful late war engines of the allies were radials. Look at the P-47M/N and the F8F, and other similar designs.

Overall the radial, because it was simple, because it was larger, could pump out more power. The flaw/drawback is that you had to design an airframe around this giant dead weight in the nose. Sometimes the extra horsepower overcame the extra drag, sometimes it wasn't worth it.
Title: Re: Radial vs. V Engines
Post by: 2bighorn on September 15, 2008, 01:05:57 PM
The most powerful late war engines of the allies were radials. Look at the P-47M/N and the F8F, and other similar designs.

They were about equal in terms of specific power and also power to weight ratios (Griffon vs R-2800)

Napier Sabre had considerable advantage in specific power over R-2800 and being about equal in power to weight ratio.
Title: Re: Radial vs. V Engines
Post by: Krusty on September 15, 2008, 01:17:40 PM
But that's where reliability comes in I guess... Sabre: highly unreliable, R2800: totally reliable.

Title: Re: Radial vs. V Engines
Post by: SectorNine50 on September 15, 2008, 04:57:19 PM
2 crankshafts? Seems kinda redundant, overly complicated, and I can see why it was unreliable.

Heck, even today we're still having gearbox problems on 2 powerplants sharing the same shaft (the Osprey development comes to mind)
Really?  The Osprey has a drive shaft going through the wings to link the engines?

Is this for RPM matching in case one fails?  I could see how in that aircraft losing one engine would be catastrophic, you'd lose every bit of control.  If it had at least one engine rotating both props, it could at least make a controlled (kinda...) landing.
Title: Re: Radial vs. V Engines
Post by: Widewing on September 15, 2008, 06:22:24 PM
Inline... Duh... :rolleyes:

I knew that... lol

You were right the first time. A 2.0 liter Honda four cylinder engine is an "inline". A V12 is a V type.

There were V12s, radials of various cylinder counts and rows from 1 thru 4. There were H-24 cylinder engines, V24s, V8s and even 6 cylinder diesels. Irrespective of the type, using the terminology of "inline" for any V engine is technically incorrect. So, you were right initially.


My regards,

Widewing
Title: Re: Radial vs. V Engines
Post by: sNiPeR on September 15, 2008, 07:00:00 PM
I just watched a video I have at home a week or two ago about the FW190.  The only reason they used radials in the 190's was because all the in-line production was committed to the 109 series.  It wasn't by choice. 


the Dora 190 had a Junkers Jumo 213A1 inline engine,hence the longer nose.
Title: Re: Radial vs. V Engines
Post by: Bronk on September 15, 2008, 07:54:43 PM
To bad this(http://upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Pratt_%26_Whitney_R-4360_Wasp_Major_1.jpg/180px-Pratt_%26_Whitney_R-4360_Wasp_Major_1.jpg)was too late for the war.

http://en.wikipedia.org/wiki/Pratt_%26_Whitney_R-4360
Title: Re: Radial vs. V Engines
Post by: Ponyace on September 15, 2008, 10:24:48 PM
Pony,

Severity of engine torque wasn't dependent on the engine configuration. A high-powered inline engine could put out just as much torque as an equivalent radial. The difference is that radial engines typically put out higher horsepower to begin with.

Your right, sax. looking back, I remember hearing about inline planes that did have bad torque characteristics. I believe the 109 had a bad turn trait to the right if I remember correctly.
Title: Re: Radial vs. V Engines
Post by: BaldEagl on September 15, 2008, 11:42:39 PM
the Dora 190 had a Junkers Jumo 213A1 inline engine,hence the longer nose.

You are correct.  I forgot that tidbit.
Title: Re: Radial vs. V Engines
Post by: SectorNine50 on September 16, 2008, 01:32:42 AM
Your right, sax. looking back, I remember hearing about inline planes that did have bad torque characteristics. I believe the 109 had a bad turn trait to the right if I remember correctly.
Yeah, pilots were told to turn to the right if engaged by a 109.
Title: Re: Radial vs. V Engines
Post by: Chalenge on September 16, 2008, 02:24:54 AM
To bad this(http://upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Pratt_%26_Whitney_R-4360_Wasp_Major_1.jpg/180px-Pratt_%26_Whitney_R-4360_Wasp_Major_1.jpg)was too late for the war.

http://en.wikipedia.org/wiki/Pratt_%26_Whitney_R-4360

Its funny that I was looking at this the other day when I found the A2A Sims 377 was out for FSX and they mentioned the P-72 so I was researching that when I found this page:

http://tbo.wikidot.com/p-72

Guy claims the plane flew for 18 months on the Russain front! Is there an alternate timeline?  :rofl
Title: Re: Radial vs. V Engines
Post by: Widewing on September 16, 2008, 02:45:21 AM
Its funny that I was looking at this the other day when I found the A2A Sims 377 was out for FSX and they mentioned the P-72 so I was researching that when I found this page:

http://tbo.wikidot.com/p-72

Guy claims the plane flew for 18 months on the Russain front! Is there an alternate timeline?  :rofl

From the website:

"Important Note.

This Website is a work of fiction set in an alternate universe. While based on certain historical events any similarity, of characters to persons living or dead, their actions and events surrounding them are purely coincidental. Although the names of historical characters appear, they do not necessarily represent the same people we know in our reality.

The novels on which this Omnipedia is based are:
The Big One

(found on Amazon at http://www.amazon.com/Big-One-Stuart-Slade/dp/1430304952/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1199983745&sr=1-1)
Anvil of Necessity

(found on Amazon at http://www.amazon.com/Anvil-Necessity-Stuart-Slade/dp/1430323574/ref=pd_bbs_sr_2?ie=UTF8&s=books&qid=1199983931&sr=1-2)
The Great Game

(to be published shortly)

Additional stories not yet published can be found at http://p099.ezboard.com/fhistorypoliticsandcurrentaffairs68862frm25"


My regards,

Widewing
Title: Re: Radial vs. V Engines
Post by: Chalenge on September 16, 2008, 02:50:50 AM
Thanks Widewing. At first glance I thought someone was trying to pull a fast one.
Title: Re: Radial vs. V Engines
Post by: lunatic1 on September 16, 2008, 12:09:26 PM
u can get hit in the engine and it will still run-in real life anyway :D
Title: Re: Radial vs. V Engines
Post by: Higgins on September 16, 2008, 04:43:12 PM
Man I just realized I haven't posted in years.  But anyhow I used to ask my Father about radial vs. inline or V configuration engines when I was a kid because of the FW-190 changing from a radial to inline in the Dora model.  The differences and advantages are many between the two, including power and torque curves, reliability, ect. that were mentioned previously in this thread. 

As far as power goes, the inline initially had less torque and power due to packaging constraints with the inline engines, but eventually as designs and technology change, the inlines have obviously proven to be a more compact, and solution that had far surpassed the radials regarding tunability (the 109's were inverted with bosch fuel injection....amazing that was in the late '30s).

The one thing to think about that made it clear as day regarding reliabilty is this.  When people mention radials being air cooled and inline engines being water cooled I used to think of the coolant lines and radiator as risky components for targets or failure, which they were, but the engine blocks themselves were the saviors.  Just as hydrolic systems had backups, many planes included duel radiators and the ability to shut off one if one was damaged or destroyed to delay the coolant from draining from the engine.

What I didn't grasp at first is think of the actual engine packaging.  The engine being the front of the aircraft increased its potential for a direct hit from head-on fire.  A radial is packaged with the cylinders in a radial design around the centerline and seperated for air to cool inbetween them but also spacing them far apart.  They can and often did take a direct hit to one cylinder, and still have little effect on the rest of the engine, even the oiling system.  Many lost cylinders completely and still made in back.  An inline engine due to its nature of design surrounding all cylinders with coolant and the oiling system throughout the block can not take any amount of direct block damage without catastrophic failure of the entire engine.  Its quite a huge difference in ease of maintanance and design realiability based on simplicity and basic design parameters that give the radials quite an advantage going into battle in WWII.  The aerodynamic limitations as well as oiling and tunability, and ultimate power limitations (late war) were the reasons for the change to inline designs.  Just my two cents regarding the intitial topic.  I still thing of my Father and this topic whenever I see a large radial designed plane.