Quote:
Originally Posted by Robo,
Hi klem, what do you (except reverse mixture lever axis) consider as a problem with the DH? In my opinion it's not too bad and the RPMs are as expected - once in the air mind you
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The control movement for the two-pitch prop went through a mid-stage where the pitch moved (not
flipped) from one setting to the other and with slow and careful movement you could actually select a rpm between the two extremes. It would of course alter with changes in power and airspeed so the pilot had to be the rpm 'governor' and adjust it but you could hold a general rpm setting that way. The result was that the general performance of the aircraft, managed that way, was almost as good as the Rotol version but it took some management. I suspect in combat it was shoved to fully fine and left there. Apparently (I've lost the link) it became an officially recommeded method of managing the aircraft for better performance. Unfortunately in CoD it
flips between the two. The A2A simulations spitfire models it correctly.
Quote:
Originally Posted by Robo.
In my experience it's quite the opposite - more heat and more strain with the BCC-O (even though the MFP gain is tiny atm). Can anyone confirm?
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I see very little change in the boost with the cutout plug pulled and that is only when I give the prop and/or throttle a little twitch which seems to "wake it up" but that could be my imagination. I do seem to be able to overtake my buddies when its pulled unless our e-states were different so I'm really not sure if its doing anything. There was a long thread about just that point but it didn't come to any amicable conclusion.
I have had engine faiure with the plug pulled for a long time (was it 10 mins + ??) with no overtemp indications.
Actually I'm a bit mystified because we can get the full +6.25lbs on full throttle without the boost override. In the MkI pilot's notes that's the max for take-off, 6.25lbs @ 3000rpm (3 mins max), max climbing +6.25lbs @ 2600 rpm (30mins max), emergency +6.25lbs@ 3000 rpm (5 mins max) max cruising +4.5lbs @ 2600rpm. (The 100 octane combat rating was +12lbs but lets stay on track with 87 octane.)
I wouldnt trust those climbing figures in CoD, I'm sure I've wrecked my engine in less than 30 minutes.
Now this report on the Merlin III
http://www.wwiiaircraftperformance.o...in3-rating.jpg
seems to relate to the 87 octane performance because it has above take-off, climb and cruise figures
but there is also a combat power rating of +12lbs. Is this what should be available with the plug pulled? I have found no other sources to indicate this is so but why would it be listed there?
Other bits and pieces suggest an uncontrolled Merlin would overboost to +17lbs and that the 100 octane engine modification was made specifically to keep the MP down to +12lbs so that obviously wasn't occurring on the 87 octane engine which had to be modified for it. In fact I have found nothing to suggest the plug needs to be pulled to get +6.25lbs, no mention of a 'normal' full throttle MP versus plug pulled MP, nor any mention of the plugs use in combat for 87 octane.
The only thing left for me to do is re-read the pilots notes for Section 1 and restudy the cockpit diagrams when I next get back to the library (I noted the above figures from Section 2).