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Old 07-23-2012, 06:18 PM
Blackdog_kt Blackdog_kt is offline
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Quote:
Originally Posted by jf1981 View Post
Leannig purpose to keep air fuel mixture to 1/15, when climbing, the less dense air means it comes to 1 of fuel for less than 15 of air in ratio, in other words, too rich of fuel, so less efficiency, some fuel is burnt meanlessly.

However as explained there's a temperature issue, generally, when the leaning is done manually, full power with rich mixture expect at very high altitude where some leaning may be needed.

When cruising one can lean further.

Except if the sim has a sort of bug, no full power should be done with lean but if one wants to shorten an engine's life. Maybe they'll model an engine failure due to incorrect leaning.

Obiously, a lot of fuel consumption reduction achieved at altitude in lean mixture, could be 20% less. I seem to remember the spit was giving 40 gph rich and 35 gph lean by 15'000 ft.
What you say is correct, with the only difference that the RAF fighters have auto-lean and auto-rich mixture. The Hurricane seems to be manual in the sim but it should be the same as the Spitfire, maybe it's just an animation error on the lever and it is in fact only two settings?

In any case, here's the short version from wikipedia:
http://en.wikipedia.org/wiki/File:Id...ichiometry.jpg

According to that graph the best air/fuel analogy for rich is 12.6:1 and for lean 15.4:1.
What the semi-automatic mixture controls do is they try to maintain these ratios, the pilot only selects if he wants rich or lean.

It is very clear however from the graph that there should be a difference in power and fuel consumption, just like you say

Quote:
Originally Posted by ATAG_Snapper View Post
Per Redroach's post above, the Spitfires have the mixture control incorrectly reversed in Cliffs of Dover. The Hurricanes have the mixture control modelled correctly: Pull backwards for Rich, push forward (toward the instrument panel) for Lean.
So, the Spit mixture controls are currently modeled like US and general aviation designs (rich is forward)? Good to know, because i thought that lean is forward and i was wondering why it's easier to start on "lean".
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