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Tallyho1961
02-16-2005, 07:20 AM
Last week I finally got around to enabling CEM and it's made the sim even more enjoyable. Based on a post to this forum I received some great CEM advice, and I've since gone through the CEM guide at Airwarfare to get a grounding in the basics.

One thing, however, still confuses me: fuel mixture settings.

I've noticed that for the a/c I fly most often: F4F, P-40, Hurricane and Spitfire, the only mixture settings available are: 100%, 120% and Auto Rich.

Here's my first question:

Why do these a/c not have the full range of mixture settings available i.e. 80% - 20% like some others? I would have thought that the more manual early war a/c, notably the F4F and Hurricane Mk I - especially the Hurricane Mk I - would have been as manual as they come.

Second question: What, if any, is the relationship between the supercharger setting and the mixture setting? Example: If I'm in an a/c at an altitude requring supercharger stage two, and have already leaned my mixture by the appropriate amount, does the supercharger setting take this into account?

It's entirely possible I'm misunderstanding some basic concepts here and I'm afraid the various CEM gides I've come across don't deal with this point.

Third question (not mixture-related): Is the WEP setting in a Hurricane or Spitfire the equivalent of 110% throttle in, say, a P-40 or F4F?

Lastly, I don't get boost, although I've noticed that the RAF a/c which have boost gauges lack a manifold pressure gauge. Is boost the English equivalent of manifold pressure?

I find CEM a very interesting subject and although I haven't noticed any major performance improvements using it yet, I figure it's another learning curve thing and the penny will drop before too long.

Thanks in advance.

Tallyho1961
02-16-2005, 07:20 AM
Last week I finally got around to enabling CEM and it's made the sim even more enjoyable. Based on a post to this forum I received some great CEM advice, and I've since gone through the CEM guide at Airwarfare to get a grounding in the basics.

One thing, however, still confuses me: fuel mixture settings.

I've noticed that for the a/c I fly most often: F4F, P-40, Hurricane and Spitfire, the only mixture settings available are: 100%, 120% and Auto Rich.

Here's my first question:

Why do these a/c not have the full range of mixture settings available i.e. 80% - 20% like some others? I would have thought that the more manual early war a/c, notably the F4F and Hurricane Mk I - especially the Hurricane Mk I - would have been as manual as they come.

Second question: What, if any, is the relationship between the supercharger setting and the mixture setting? Example: If I'm in an a/c at an altitude requring supercharger stage two, and have already leaned my mixture by the appropriate amount, does the supercharger setting take this into account?

It's entirely possible I'm misunderstanding some basic concepts here and I'm afraid the various CEM gides I've come across don't deal with this point.

Third question (not mixture-related): Is the WEP setting in a Hurricane or Spitfire the equivalent of 110% throttle in, say, a P-40 or F4F?

Lastly, I don't get boost, although I've noticed that the RAF a/c which have boost gauges lack a manifold pressure gauge. Is boost the English equivalent of manifold pressure?

I find CEM a very interesting subject and although I haven't noticed any major performance improvements using it yet, I figure it's another learning curve thing and the penny will drop before too long.

Thanks in advance.

x6BL_Brando
02-16-2005, 07:51 AM
Hi,

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>first question: <HR></BLOCKQUOTE>

I'm not sure why you aren't getting the full range? It is available but you maybe don't have the appropriate keys mapped.
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Second question: <HR></BLOCKQUOTE>
A good point! It would take a little research and experiment to see if or how that relationship is modelled.

I think that WEP and 110% have the same effect in combat situations.....bearing in mind that the engine should never be run @ full throttle or WEP for extended periods. You will need to remember that WEP must be switched in & out, rather than just backing off the throttle. I know that sounds obvious, and no offence is meant.....in the heat of battle it's easy to forget whether it's on or off; likewise for radiator settings, prop-pitch, supercharger-stage, mixture-setting. http://forums.ubi.com/images/smilies/53.gif

Main culprit for me has always been the supercharger: I've been caught in a sluggish, struggling kite too many times when the a high-alt fight has been dragged down! http://forums.ubi.com/images/smilies/16x16_smiley-sad.gif
I've just about learned that now.

As I understand it, the key, engine-related gauges in the Spit's and Hurri's are the boost and the tacho. Temperature gauges should be watched carefully too, especially in the early variants. Note also that many of the later planes run fully-automated.

I really enjoy the CEM controls.

Tallyho1961
02-16-2005, 08:24 AM
Hi Brando,

Re: mixture settings - my key bindings work (I've got a mixture increase and mixture decrease set up, as opposed to buttons for specific settings) because in some a/c I am able to get the 80-20% range, but not in those I quoted - F4F, P-40 and RAF a/c - which is what I find odd. Are you able to get leaner mixture settings in these a/c?

Re: WEP - yes I know to switch it on and off - I've got a button on my X45 set up for just that purpose. Are you confirming that WEP and 110% throttle are just two different ways of achieving the same thing?

I like CEM, too. That's why I care. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Maple_Tiger
02-16-2005, 10:18 AM
Some aircraft, like the P-40, F4F, P-51, P-47, P-38, Spitfire, and Corsair, have auto Mixture. Hence, I just leave it at auto rich. However, the P-47, P-38, and P-51 have a fully automatic mixture. Thus, you can't change anything.

The supercharger is normaly changed when you reach a certain altitude. I can usualy tell by the manafold pressure on whether or not to change the supercharger.

Some aircaft, like the P-51, P-38, and P-47, have auto superchargers; thus, you can't change them manualy.

Tallyho1961
02-16-2005, 11:44 AM
I guess some of the information I'm looking at is incorrect. In the IL2 Advanced Manual it lists the Hurricane and P-40 series as having manual mixture control, which I assumed was correct.

I've just had a look at the super-useful 'panels' section over at the 310VFS-380VBG Web site and they show Hurri/Spit/P-40 as automatic, which explains why I can't change the mixture, other than to 120%. They do, however, show the F4F as manual mixture, which according to me it isn't.

I guess that's one less thing to think about, which isn't a bad thing.

S!