hurricane problems

[Viper2000]

Originally Posted by *Buzzsaw*

Sustained Combat setting for Hurricane when CEM is on:

+3 boost, full rich mix, 2800 rpm, full rad open, Prop pitch full fine


Full Combat setting for Hurricane when CEM is on: (use for 5 minutes)

+4 boost, full rich mix, 3000 rpm, full rad open, Prop pitch full fine


Emerg Combat setting for Hurricane when CEM is on: (use only for 1 minute at a time)

+6 boost, full rich mix, 3000 rpm, full rad open, Prop pitch full fine

In most cases, you are best to decide on your settings in combat, and leave them, just fly the plane, don't be playing with the boost and rpm unless you are in a difficult situation. I usually enter combat with settings on my 'Full Combat', then drop them to 'Sustained Combat' after 5 minutes, then back up to 'Full Combat' after a break of a couple minutes. I use 'Emerg Combat' only when absolutely necessary.

Remember when you reduce RPM's boost rises, when you increase RPM's, it drops, so you need to be careful and adjust your boost throttle when you adjust RPM. (pitch)

Couple of points.

1) You'd be more historically accurate in this period if you used 2600 rpm for max continuous; 2650 came later.

2) The relationship between boost and revs is a bit more complex than that.

The Merlin III has the original supercharger design, which suffered from some questionable design decisions made before RR hired SGH. It was not very efficient. Maximum performance was actually obtained at about 2800 rpm until the FTH for the desired boost was reached; above this altitude it was better to go to 3000 rpm to get more boost despite the frictional losses (and increased engine wear).

This is the main reason for the two different combat concessions in the Pilot's Notes; the central entry supercharger was considerably more efficient and therefore later marks of Merlin used 3000 rpm for combat power at all altitudes.

[I'm not very impressed with the massive boost increases associated with reducing revs, because it's quite hard to see where this can come from; the supercharger puts in kinetic energy from its tip speed (which is fixed at constant engine rpm), plus a component due to the radial flow along the vanes. This is then diffused into a pressure rise. There are therefore strict limits to the maximum supercharger pressure ratio obtainable at any given rpm. In reality, there might be a small increase in boost during a deceleration transient, but large increases are unlikely since the engine charge consumption varies directly with rpm, whilst the kinetic energy at the supercharger tip varies as the square of rpm. So in general one would expect boost to fall with rpm under normal circumstances - this might change at very low intake manifold pressures at or close to ground idle because of scavenging effects, but that's very much an edge case.]

[Plt Off JRB Meaker]

A little tip,learn to use the CEM first and then once you've grasped that learn to use the Engine temperature effects.

Trying to grasp both when you've just started out is a headache and it will be difficult to understand what's happening to your aircraft,from your actions your making.

[firehawk66]

Thanks fellas for your excellent responses,I feel I should apologise for my rant since it was written just after quitting the game and I still had my knickers in a twist.
I am surprised that non CEM seems to be so inaccurate but I do fly IL21946 in CEM so hopefully I can use that knowledge in this sim.
Buzzsaw, thanks for the engine settings data it leads me to think that a sticky topic could be started with these settings for the different aircraft in game as a good reference for anyone who wants to improve their flying skills.
Thank you all

[*Buzzsaw*]

Originally Posted by firehawk66

Thanks fellas for your excellent responses,I feel I should apologise for my rant since it was written just after quitting the game and I still had my knickers in a twist.
I am surprised that non CEM seems to be so inaccurate but I do fly IL21946 in CEM so hopefully I can use that knowledge in this sim.
Buzzsaw, thanks for the engine settings data it leads me to think that a sticky topic could be started with these settings for the different aircraft in game as a good reference for anyone who wants to improve their flying skills.
Thank you all

Salute Firehawk

Best way to practice is to select the cross country England Quick Mission, but double click on the pic of the Blenheim and select the Hurri Rotol instead. Then practice maneuvering aggressively with CEM on, using the various settings which I have listed until you are comfortable and not destroying your engine regularly.

For takeoff, use the Emerg Combat setting, but make sure you reduce to sustained combat immediately after takeoff. I usually use a 3000 rpm setting for landing, (after initially reducing speed and power to 0 and getting flaps and wheels deployed, which requires reducing speed to 120 mph) it gives you enough power if you need to abort your approach. (and obviously you have to play with your boost settings as you are on your glide path, but you need quite a bit of power with wheels down and flaps deployed to keep in the air)

Also whenever using the 'Lean Mix' setting, be absolutely sure not to take the boost over '0' or the RPM over 2650, because if you do, you can fry your engine very quickly. If you want to be safe, just use full rich mix. I usually only use the lean setting when I am low on fuel and returning to base, or when I know I am going to be on station for a long time.

Another thing which you need to practice and focus on is trim. To get max speed and performance, your aircraft needs to be trimmed to fly hands off straight and level. Rudder and Elevator trim are the only ones which can be adjusted for the British planes. After a while you get used to trimming all the time. Note that as your speed changes, your trim will change. So when you are doing 170 mph, and you trim, you will gain speed, then as you get moving faster, you will need to trim again, etc.

[firehawk66]

Thanks Buzzsaw, I have just been on a free flight trying out the settings and practicing combat manoevering.
I find though that at +3Lbs of boost I cannot attain 2800rpm with the prop pitch at fully forward,also I notice that with the Rotol the mixture lever is the correct ( reversed ) way round whereas the DH is incorrectly modelled...confusing or what.
Also even with full CEM and engine temp activated I still cannot catch those blasted BF110s, lord knows how the 109s will run rings round me...